Scientia Agricultura Sinica-Forthcoming Articles Forthcoming Articles http://journals.caass.org.cn/zgnykx EN-US http://journals.caass.org.cn/zgnykx/EN/current.shtml http://journals.caass.org.cn/zgnykx 5 <![CDATA[The Effect of Subsoiling Combined with Straw Returning Measure on Pore Structure of Black Soil]]> . Aimed at such problem, our research was conducted in order to provide scientific basis for the influence mechanism of this measure on soil structure of black soil and the establishment of reasonable tillage.【Method】In this study, a 5-year field positioning experiment conducted in Qinggang County, Suihua City, Heilongjiang Province, a typical black soil area in Northeast China was used as a platform. Farmers’ conventional treatment (FP) , 25 cm subsoiling alone treatment (T2), 25 cm subsoiling combined with straw returning treatment (T3) and 35 cm subsoiling combined with straw returning treatment (T4) were set. The visualization and quantification of soil pore structure were studied using CT scanning technology, and combined with field capacity and bulk density to explore the effect of subsoiling combined with straw returning on the pore structure of black soil. 【Result】The results showed that the two-dimensional and three-dimensional images of soil pores clearly showed that the pore distribution at 0-20 cm soil layer was significantly less than that at 20-40 cm soil layer in all treatments, while the pore distribution of suboiling combined with straw returning treatment (T3 and T4) was significantly higher than that of FP treatment, and their macropores with more complex structure were increased. Quantitative analysis showed that compared with FP treatment, the total porosity of 20-30 cm soil layer was significantly increased by 103.0% (P<0.05) under 25 cm subsoiling alone treatment (T2), which was achieved by significantly increasing the micropores porosity(pore diameter d≤0.50 mm) by 91.3% and mesopores porosity (0.50 mmP<0.05). While subsowing combined with straw returning treatments (T3 and T4) significantly increased the total porosity of 0-30 cm soil layer by 109.8%—382.7% (P<0.05), which was achieved by significantly increasing the macropores porosity (d>1.00 mm) by 221.5%-661.7% and the mesopores porosity by 105.4%-544.9% (P<0.05). In addition, compared with FP treatment, subsoiling combined with straw returning (T3 and T4) significantly increased the fractal dimension of soil pores at 0-30cm soil layer by 9.9%-17.7% (P<0.05), decreased the Euler number by 32.4%-66.4% (P<0.05), significantly increased the field water capacity by 24.2%-40.6% (P<0.05). Further analysis showed that the different pore size porosity and total porosity was significantly positively correlated with field capacity and fractal dimension, but significantly negatively correlated with Euler number (P<0.01). 【Conclusion】Subsoiling combined with straw returning measure can improve porosity of macropores and mesopores pore of black soil, improve pore structure and connectivity, and increase field capacity, which can be recommended measure for rational tillage construction in black soil of Northeast China.


]]> <![CDATA[The Protective Efficacy of Vaccines Against H9N2 Avian Influenza Virus of Branch h9.4.2.5 Isolated in China]]> 】There are many commercial inactivated vaccines against the H9 subtype avian influenza approved for use in China, and their protection efficacy and selection have been widely concerned by farmers. Evaluation of protection efficacy of main commercial vaccines against H9N2 viruses recently isolated in the field are of great significance for guiding the prevention and control of H9 subtype AI by immunization in China.【Method】According to the vaccine batch release of the National Veterinary Drug Basic Information Database in China, 4 commercial vaccines (labeled as A-D) with large batches were selected from 40 kinds of sold H9 commercial vaccines. The four H9N2 subtype AIV, CK/XJ/S1204/2015, DK/JX/S4512/2017, CK/YN/S1666/2020 and CK/NX/S4590/2020, belong to h9.4.2.5 branch, isolated at different times and places were used in this study to evaluate the protection efficacy of selected commercial H9 subtype AI vaccines. The 50% chicken embryo  infection (EID50), 50% chicken infection (CID50), and 50% cell infection (TCID50) of the four viruses were tested to determine the challenge dose of the animal experiment and the infection dose of the cell test. 40 3-week-old SPF chickens were injected intramuscularly with 4 kinds of inactivated vaccine, and groups of 10 similar SPF chickens were inoculated with PBS as control group. 3 weeks post vaccination(p.v.), the serum of all experimental chickens were collected before challenge, hemagglutination inhibition (HI) and neutralization (NT) antibody titers were detected by HI test and neutralization test; The 40 immunized chickens of each vaccine were randomly divided into four groups, 10 chickens of each vaccine and 10 control chickens were infected intranasally with the 10CID50.of each H9N2 virus. Oropharyngeal and cloacal swabs were collected on days 3 and 5 post challenge(p.c.) for virus shedding detection and calculation of the protective rate of each vaccine. 【Result】The CID50 of the four strains were 103.5 EID50/0.1 mL, 102.5 EID50/0.1 mL, 102.5 EID50/0.1 m and  103.5 EID50/0.1 mL, respectively. At three weeks p.v., the mean HI antibodies titers against the commercial H9 subtype HI test antigen (CK/SH/10/2001) in 4 groups of vaccinated chickens ranged from 9.4log2 to 11log2, the mean HI antibodies titers against challenge virus in 4 groups of vaccinated chickens ranged from 4.6log2 to 10.8log2, and significant differences of HI antibodies titers were observed among different vaccine groups, the maximum difference of mean HI antibodies titers were 64-fold among them. The mean NT antibodies titers against challenge virus in 4 groups of vaccinated chickens ranged from 6.7log2 to 12.2log2, the maximum difference of mean HI antibodies titers were 32-fold among them, the HI antibody and NT antibody of the control group were negative. After intranasal infection with different H9 viruses, the immune effects of the four vaccines were quite different. In CK/XJ/S1204/2015 challenged groups, 3 vaccines (B-D) could provide more than 80% protection. In DK/JX/S4512/2017 challenged groups, 1 vaccine (B) can provide more than 80% protection. In CK/YN/S1666/2020 challenged groups, 2 vaccines (A and B) can provide more than 80% protection. In CK/NX/S4590/2020 challenged groups, the protection efficacy of the four vaccines (A-D) were all less than 80%. In the same period, the virus shedding rate of chickens in the control group was more than 8 /10. 【Conclusion】There was a great difference in the immune protection efficacy of the four kinds of commercial vaccines after challenge with recently isolated H9 strains, and the difference of antigenicity between vaccine antigens and isolates was the main reason for the decrease of immune protection efficacy of the commercial vaccines. The titers of HI antibody and NT antibody against H9N2 prevalent strains could be as important data for evaluation of the commercial H9N2 AI vaccines. This study provides scientific references for selection and usage of the commercial vaccines against H9N2 AI.



]]> <![CDATA[Effects of Pladienolide B on Expression of Pluripotency Related Genes and Cell Viability of Bovine Embryonic Stem Cells]]> 】 Due to their high pluripotency, bovine embryonic stem cells (BESCs) have important application values in cattle breed conservation, breed selection and studying the regulation mechanism of livestock embryo development. However, studies on the maintenance of pluripotency and differentiation of BESCs are limited, the regulative mechanism remain unclear. 【Objective】To investigate the effects of different concentrations of Pladienolide B (PlaB) on the expression of pluripotent markers, totipotent markers and embryonic cell-lineage genes as well as the cell viability of BESCs which will provide reference and theoretical basis for improving the developmental potency of BESCs.【Method】Immunofluorescence was used to detect the expression of pluripotent markers of bovine BESCs, and real-time fluorescence quantitative PCR (RT-qPCR) was used to detect the effects of different concentrations of PlaB on the expression of spliceosome, totipotent markers and embryonic cell-lineage genes of BESCs. RT-qPCR and Western Blot were used to detect the effects of different concentrations of PlaB on both mRNA and protein expression of pluripotent markers of BESCs. CCK8 and EDU staining was used to detect the effects of different concentrations of PlaB on the proliferation of BESCs. 【Result】1. RT-qPCR results showed that the mRNA expression levels of SF3B1 and SF3B2 in EPSCM-BESCs were significantly down-regulated by 0.5nM to 1.5nM PlaB; When the PlaB concentration was 1.5nM, the mRNA expression of SF3B1 and SF3B2 in CTFR-BESCs were decreased; When the PlaB concentration ranged from 0.5nM to 1.5nM, the mRNA expression levels of SF3B4 and SF3B5 in both CTFR-BESCs and EPSCM-BESCs were increased in a dose-dependent manner. Furthermore, PlaB significantly down-regulated mRNA expression of SF3B6 in the CTFR-BESCs. While PlaB concentration ranged from 0.5nM to 1.5nM, the mRNA expression of spliceosome LSM4 both in EPSCM-BESCs and CTFR-BESCs were significantly down-regulated. The concentration from 0.5nM to 1.5nM PlaB significantly down-regulated the expression levels of EFTUD2 mRNA in CTFR-BESCs; The mRNA expression of EFTUD2 mRNA was significantly down-regulated in BEPSCM-BESCs with 1nM and 1.5nM PlaB while PlaB concentration from 0.5 to 1.5nM, both the mRNA expression and protein levels of the pluripotent markers OCT4, SOX2 and NANOG in CTFR-BESCs and EPSCM-BESCs were up-regulated in a dose-dependent manner. By the concentration range from 0.5 to 1.5nM, PlaB dose-dependently up-regulated the mRNA levels of totipotent markers such as MDM2, PID1 and BTG2 in CTFR-BESCs and EPSCM-BESCs, while the mRNA levels of DDIT4 and PDRG1 were down-regulated. The mRNA expression of embryonic cell lineage genes in the CTFR-BESCs were up-regulated while the PlaB was added. The addition of PlaB in EPSCM-BESCs significantly reduced the expression of GATA4, GATA6, SOX7 and other embryonic cell lineage genes, but had no significant effect on ZIC1. The cell viability of CTFR-BESCs and EPSCM-BESCs showed a downward trend with increasing of PlaB dose and treatment time. And CTFR-BESCs was more sensitive than EPSCM-BESCs. 【Conclusion】PlaB significantly up-regulated the expression of pluripotent markers and partially totipotent markers in CTFR-BESCs and EPSCM-BESCs. The expression of gene lineages and cell viability in EPSCM-BESCs were decreased. The effective concentration and effects on gene expression of PlaB in the two BESCs were not completely consistent. Due to the inhibiting effect of PlaB on cell viability of BESCs, further studies are needed to optimize the culture system.


]]> <![CDATA[UAV Multispectral Image-based Nitrogen Content Prediction and the Transferability of the Models in Winter Wheat Plant]]> 】Accurate monitoring and rational application of nitrogen are particularly important for healthy growth, yield and quality improvement of wheat, and reduction of environmental pollution and resource waste. To develop UAV-based models for accurately and effectively assessment of the plant nitrogen content in the key growth stages of wheat growth, explore the transferability of the models constructed based on machine learning methods. 【Method】Winter wheat experiment plots in Shang shui country, Henan province, China were conducted from 2020 to 2022. Based on the K6 multichannel imager mounted on DJM600 UAV, 5-band (Red, Green, Blue, Red edge, and Nir) multispectral images were obtained from a UAV system in the stages of jointing, booting, flowering and filling in winter wheat, and used to calculate 20 vegetation indices and 40 texture features from different band combinations. Correlation analysis was used to screen the sensitive characteristics of nitrogen content in winter wheat plants from the 65 image features. Combining the sensitive spectral features and texture features of the nitrogen content of winter wheat plants, BP neural network (BP), random forest (RF), AdaBoost, and support vector machine (SVR) machine learning regression methods were used to build plant nitrogen content models, and compared for the model performance and transferability. 【Result】(1)The correlation coefficients between plant nitrogen content and image features passed the test of 0.01 extremely significant level, including 22 spectral features and 29 texture features. (2) 51 spectral and texture features were adopted to build four machine learning models. The estimates of plant nitrogen by the RF and AdaBoost methods were relatively concentrated, mostly close to the 1:1 line; while the estimates from the BP and SVR methods were relatively scattered. The RF method was the best, with R2, RMSE, and MAE of 0.81, 0.42%, and 0.30%, respectively; The SVR method was the worst, with R2, RMSE, and MAE of 0.66, 0.54% and 0.40 %, respectively. (3) The prediction effects of the four methods on the nitrogen content of W0 and W1 treatments trained using W1 and W0 treatments were the same as those trained using both W0 and W1 datasets, both of which were closer to the 1:1 line for the RF and Adaboost methods. The R2 of transfer prediction results for the models constructed by BP, RF, Adaboost, and SVR methods were 0.75, 0.72, 0.72, and 0.66 for the prediction of nitrogen content in W0 treatment and 0.51, 0.69, 0.61 (trained using data from W1 treatment) and 0.45 for the prediction in W1 treatment (trained using data from W0 treatment), respectively.【Conclusion】All models showed strong transferability, especially the RF and Adaboost methods, in predicting winter wheat nitrogen content under rainfed and irrigation water management.


]]> <![CDATA[Effect of Deep Tillage under Continuous Rotary Tillage on Yield Formation of High-quality Japonica Rice in Cold Region]]> 】The effects of deep tillage under continuous rotary tillage on growth dynamics, photosynthetic matter production and yield formation of different japonica rice were studied in order to provide technical support for high yield and high efficiency cultivation of high quality japonica rice in cold regions. 【Method】A field experiment was conducted in 2018-2019, under the condition of straw returning to the field, on the basis of rotary tillage in the previous stubble for two consecutive years. Here, two tillage practices, namely, deep tillage and rotary tillage were adopted during the growth stages of three modern japonica varieties Suijing18, Kendao12, and Sanjiang6. The effects of deep tillage and rotary tillage on the growth dynamics and post-anthesis production characteristics of high-quality japonica rice were studied. 【Result】There was no significant difference in yield between years, but tillage methods had significant effects on the growth and development, photosynthetic dry matter production characteristics and yield characters of high-quality japonica rice in cold regions. Compared with rotary tillage, deep tillage significantly increased the number of tillers per square meter and the number of effective panicles, the flag leaf unfolded later and lasted longer, and the heading was late but the duration did not change. The biomass and dry matter transport capacity of stem and sheath increased, and the biomass and stem-sheath dry matter transport capacity were increased by 8.34% and 5.36% respectively at full heading stage. The output, output rate and transformation rate of stem and sheath matter increased by 13.19%, 6.70% and 9.17% respectively (P<0.05). It increased the leaf area index at full heading and mature stage, prolonged the duration of green leaf area and increased the population growth rate. The internode length, leaf length and width of the third and fourth nodes of the main stem were increased, plant height and ear length were increased, the number of grains per ear and grain weight per ear increased by 7.05% and 3.37% respectively, the harvest index increased by 1.90%, and the average yield increased by 12.78%. Under the same tillage method, Kendao12 was the best in tiller number, photosynthetic matter production capacity, stem and sheath dry matter accumulation and transport capacity, yield and its composition, followed by Suijing18, while Sanjiang6 had higher leaf area index after anthesis, grain number per panicle and grain weight at mature stage, but could not make up for its low dry matter transport capacity, effective panicle number and 1000-grain weight. In terms of interaction effect, the combination of deep tillage × Kendao12 treatment showed higher effective panicles per square meter, strong production and transport capacity of photosynthetic matter after anthesis, high grain-leaf ratio and population growth rate, high 1000-grain weight and harvest index, reasonable allocation of plant agronomic morphological characters and coordination of yield traits, which could achieve a yield increase of 9.15%-27.47%.【Conclusion】Continuous rotary tillage combined with one-year deep tillage is the most effective and sustainable rice tillage system to improve the yield of high-quality japonica rice in this region.


]]> <![CDATA[Apparent Matrix Effect of Yeast Polysaccharides from S. cerevisiae on the Hydrolysis of Wine Fruity Esters]]>  S. cerevisiae on the hydrolysis of fruity ester and explore the potential application of yeast polysaccharide in stabilizing wine aroma profile and expand shelf life of product. 【Method】YP was extracted from S. cerevisiae by hot water extraction and alkali methods, and the basic components of YP were analyzed by UV spectrophotometer, GC and HPLC. The model wine containing the conventional concentration of fruity esters was prepared and treated with YP, and the concentration of YP was set in the range of 0—2.0 g.L-1. The effect of YP on the volatility of fruity esters was analyzed by the static headspace method. Next, model wines with different treatments were stored at 4°C for 6 months, and the content of fruity esters in model wine was regularly monitored. Finally, sensory analysis was used to evaluate the aroma notes of model wine stored 6-months. 【Result】Instrumental analysis showed that the total polysaccharide content of YP is (72.61±3.29)%, and the protein contents accounts for (11.20±0.02)%. The main monosaccharide composition of YP is mannose and glucose, and their molar ratio is 1.790:1. Molecular weight of YP is 576 Da, 18 kDa, 163 kDa and 21819 kDa. Static headspace analysis indicated that YP treatment could reduce the volatility of acetate esters in model wine, especially 0.8 g?L-1. While YP treatment could increase the volatility of ethyl esters. Data of regular sampling found that the hydrolysis rate of ethyl esters was significantly higher than that of acetate esters during 6 months storage. Compared with the control, 0.4-0.8 g?L-1 YP slowed down the hydrolysis of acetate esters and ethyl esters by 10%—40% and 3.7%—26.7%. Sensory analysis showed that model wine added with YP showed higher MF% of temperate sour and sweet fruity，preserved fruit and floral aroma notes of wine samples compared with the control. 【Conclusion】From the study of model wine system, it was concluded that adding 0.4—0.8 g?L-1 YP during wine storage slowed down the hydrolysis of fruity esters, stabilized wine fruity aroma profile and showed potential application value for prolonging wine shelf life.


]]> <![CDATA[The Structure and Development of Segment Membranes in Citrus Fruits]]> 】This study aims to reveal the development of segment membrane which contributes to citrus fruit mastication. 【Method】Using different citrus types (hybrid citruses including Ehime No. 30 and Nova, Okitsu Wase satsuma mandarin, navel oranges including Yuanfeng and Newhall, and pumeloes including Anjiang and Jiangyong), the main physiological and biochemical properties of segment membrane were analyzed by comparisons in tissue development and cell ultrastructure.【Result】The results showed that rough outside but smooth inside of segment membrane occurred in all citrus types. Obviously waxy layer grew on the inside of segment membrane under which one or two cell layers with thickened cell wall arranged neatly. Cell density decreased gradually from inside to outside in segment membrane. Occurrence of wax layer in the inside and morphological changes of cells under the wax layer emblematized the maturation of citrus segment membrane. For pomelo, the thickest segment membrane linked with the worst mastication was caused from a large number of cell layers, enlarged cell size and more pectin in segment membrane. At early fruit development from squaring stage to flower withering stage, ventricles differentiated already in the ovary and the intervals between ventricles would develop into segment membranes. In the period, parenchyma cells in the intervals exhibited equal cell size and arranged neatly, having no segment membrane characteristics. With fruit enlargement and maturation, segment membranes of Shatian pomelo had the most cell layers and the longest cell wall thickening period. Segment membranes of Shatian pomelo showed significantly higher pectin content than that of Yuanfeng navel orange and Juxiangzao Satsuma mandarin. Segment membranes of Yuanfeng navel orange had medium cell layers and moderate cell wall thickening period, in which protopectin was higher than that of Juxiangzao Satsuma mandarin. Segment membranes of Juxiangzao exposed the least cell layers and the shortest cell wall thickening period. In October when Juxiangzao matured, segment membrane protopectins in Shatian pomelo, Yuanfeng navel orange and Juxiangzao Satsuma mandarin were 364.22, 208.48 and 165.39 mg.g-1 respectively, with Shatian pomelo reaching 74.7% and 120.2% higher than another two varieties. 【Conclusion】Segment membrane thickness, cell layers in segment membrane and degree of cell wall thickening associate with citrus fruit mastication. Pectin content could reflect the mastication of citrus segment membranes.


]]> <![CDATA[Genomic Selection for Fruit Weight and Soluble Solid Contents in Fruit of Peach]]> 】Fruit weight and soluble solid content (SSC) are two important quantitative traits in peach which are concerned by breeders and controlled by multiple minor genes. Therefore, it is difficult to perform early prediction by a single marker. As a novel genome-wide tool, genomic selection has been applied in fruit crops and expected to enhance breeding efficiency of those quantitative traits. However, its application effect in peach and influencing factors still need to be further explored.【Method】The objectives of this study were to assess the accuracy of prediction in nature and cross populations of peach for fruit weight and soluble solid content (SSC) by using genomic selection. In this study, the training population comprised 520 individuals were selected as materials. Using the genotypic data for 48,398 SNPs obtained from the resequencing results of above training population, a total of 11 genome-wide prediction models were built to select the optimum model for fruit weight and SSC. Then, we calculated the genomic breeding values of a small panel of nature population comprised 56 individuals and 29 cross populations comprising 1145 seedlings.【Result】The average sequencing data of each variety of the three groups was 1.95~3.52 Gb, and the sequencing depth was 5.29~10.79×. The sequencing data of the training natural population was algned with the reference genome, a total of 5,065,726 single nucleotide polymorphism (SNPs) were obtained. After removing the SNPs with high missing rate more than 20% and minor allele frequency lower than 0.05, a total of 48,398 SNPs on the genome were randomly selected for constructing whole-genome selection models for the training population. The model with the highest prediction accuracy for fruit weight is BayesA, and the model with the highest prediction accuracy for SSC is randomforest. Using the above two models, we found that the goodness of fit between the predicted breeding values and observed phenotype of fruit weight was 0.4767~0.6141, higher than that of SSC (0.3220~0.4329) in nature populations. And in cross populations, the prediction accuracy of fruit weight was 0.2319~0.4870, also showing higher than that of SSC (0.0200~0.2793).. The results also showed that the prediction model constructed by training natural populations was more accurate in predicting natural populations but of cross populations. Taking fruit weight as an example, we also found that only 17.78% of the seedlings need to be retained by genomic selection when targeted large fruit. Its efficiency is significantly higher than that of single and double marker selection. Finally, the effects of population dispersion, heritability and population structure on prediction accuracy also were discussed. The results indicated that prediction accuracy may be mixed and affected by a combination of several factors.【Conclusion】In this study, a suitable genomic selection model for peach fruit weight and SSC was screened and confirmed that the prediction efficiency of genomic selection was significantly higher than that of single marker selection. The results underline the potential of genomic prediction to accelerate breeding progress of these two quantitative traits in peach.


]]> <![CDATA[Dynamics of Straw Decomposition and Nutrient Release Under Different C/N Ratios]]> 】Understanding the decomposition, nutrient release characteristics and driving factors of straw under different C/N ratio based on coal mining area could provide theoretical basis for the full utilization of straw resources and reclaimed soil fertility improvement.【Method】Air-dried maize straw and wheat straw cut into 2 mm pieces were selected for decomposition experiment of a coal mining reclamation area in Shanxi province. Two C/N ratio levels of 25 and 10 were designed in maize straw and wheat straw by supplementing urea, taking no nitrogen application that C/N ratio levels was 52 and 74 as the control. All the straws (8g in organic carbon) were put into a nylon mesh bag (0.38 μm aperture), and horizontally buried into 15cm deep of soil. On the 12, 23, 55, 218, 281 and 365 days since buried, samples were collected from the bags to analyze the dynamic of the dry matter residue and nutrient (carbon, nitrogen, phosphorus and potassium). 【Result】During the first 55 days, adjusting the C/N on 25 with the application N was the best way to accelerate the decomposition of maize straw. And adjusting the C/N on 10 was the best way to accelerate the decomposition of wheat straw. Application N could significantly promote the release of carbon and phosphorus from maize straw during the first 55 days. Application N could significantly accelerate the release of carbon, nitrogen and phosphorus from wheat straw, but had no significant effect on the release of potassium. The thermal equation of straw decomposition and nitrogen and potassium release was better than the temporal equation, and phosphorus release from straw was not suitable for the exponential decay equation. When the accumulated temperature was 4 600℃, the average release rates of carbon, nitrogen, phosphorus and potassium from straw were 49.2%, 39.5%, 40.8% and 9.3%; When the accumulated temperature reached 1 125℃, more than 85% the potassium of straw was released. The decomposition of straw was mainly influenced by the temperature, organic carbon, lignin and hemicellulose. 【Conclusion】Application N could accelerate the decomposition of maize straw and the release of carbon and phosphorus in the early stage, and application N could significantly accelerate the wheat straw decomposition and the release of carbon, nitrogen and phosphorus. Temperature could better reflect the process of straw decomposition and nitrogen, potassium release than time, the decomposition of straw was mainly regulated by the temperature, organic carbon, lignin and hemicellulose. Therefore, combined with the hydrothermal conditions in the coal mining area, the straw with an appropriate amount of urea should be returned to the field in the right time to improve the content of nitrogen, phosphorus and potassium of the reclaimed soil.


]]> <![CDATA[Effect of No-Till Combined with Mulching on the Structure and Organic Carbon Content of Agglomerates in Heilu Soils of the Weibei Dry Plateau]]> Objective】To clarify the effects of long-term no-tillage and mulching measures on soil aggregate structure and organic carbon content in Weibei dry plateau farmland, and to explore suitable tillage measures to improve the regional soil.【Method】On the basis of continuous 16-year field positioning experiments, traditional tillage (CT), no-tillage and no mulch (NT), no-tillage + straw mulch (NS), no-tillage + plastic film mulching (NP), no-tillage + A total of 5 field management measures, including straw + plastic film mulching (NSP), were used. The 0-40 cm ring knife and profile soil samples were collected during the spring corn harvest in October 2019, and the bulk density, aggregate particle size distribution and organic carbon content were determined.【Result】(1) No-tillage and mulching measures (NT, NP, NS and NSP) affected the bulk density and aggregate size distribution of Heilu soil. No-tillage and mulching measures both increased the soil bulk density of the plough layer, of which 0-10 cm increased significantly (6.8%-17.8%). The changes of bulk density and porosity of the plough layer were opposite to those of the plough layer. The proportion of micro-aggregates was significantly reduced, which promoted the transformation of micro-aggregates into macro-aggregates. The weight percentage of aggregates of each particle size in the plough layer (0-20 cm) is distributed as follows: larger aggregates (0.25-2 mm) > large aggregates (>2 mm) > micro aggregates (0.053-0.25 mm) > powder. The clay fraction (<0.053 mm), the larger aggregates and silty clay fractions in the plow bottom layer (20-40 cm) were significantly higher than the macroaggregates and microaggregates. (2) Under no-tillage and mulching measures, the organic carbon content increased with the increase of aggregate particle size. In the 0-40 cm soil layer, the organic carbon content of the aggregates of each particle size in the NT treatment was significantly lower than that in the CT treatment, while the NS and NSP treatments were significantly higher than those in the CT treatment. (3) The particle size distribution of aggregates is the dominant factor causing the change of the nutrient contribution rate of aggregates. The total organic carbon accumulation in the plough layer is dominated by aggregates >0.25 mm, and the plough layer is mainly composed of silty clay components and organic carbon in larger aggregates main. 【Conclusion】Long-term no-tillage and mulching measures promote the transformation of micro-aggregates into macro-aggregates in the plough layer. Compared with traditional tillage, no-tillage and plastic film mulching decreased the organic carbon content of aggregates of various particle sizes in Heilong soil and in the plough layer, respectively. However, no-tillage mulching (NS, NP and NSP) increased the organic carbon content of aggregates of each particle size compared with no mulching. Straw mulching alone had the best effect, and significantly improved the bulk density and aggregate particle size distribution, which was the best treatment.


]]> <![CDATA[Origin, Present Situation and Development Trend of Green Fertilizer]]> Nutrient-efficient green fertilizers; Carbon-fixing and fertilizing green fertilizers; Efficiency-enhancing and nutrient conversion efficiency green fertilizers; Nutrient-balanced green fertilizers; Value-added green fertilizers. How to realize the green transformation of chemical fertilizers and the efficient and low-cost utilization of organic fertilizer resources, there are four main suggestions. (1) Rely on market mechanisms, strengthen top-level design, and build a new system of green fertilizer manufacturing; (2) Take the integrated management of nutrient resources as the core, and promote the balanced and coordinated development of organic-mass-element-micro-element fertilizers; (3) Fully play the role of scientific research platforms, and greatly develop intelligent green fertilizer products; (4) Integrate modern sensing and information technology to thoroughly promote green and efficient precision fertilization. This paper provides an overview of the background, concept, types and characteristics of green fertilizers proposed, and discusses the future development direction, in order to provide insight into the green transformation of China's fertilizer industry and the green development of agriculture in the future.


]]> <![CDATA[Effect of Heat Stress on DNA Methylation of GNAS Promoter Region in Dairy Cows]]> Objective】Heat stress has seriously impaired the production and health of dairy cows, causing the subsequent limitation in sustainable development of dairy industry. DNA methylation is an important epigenetic regulatory mechanism involved in an animal’s heat stress response, the potential function and molecular mechanisms of which are not clear. The current study was conducted to detect the DNA methylation related to heat stress in dairy cows and identify target genes related to DNA methylation, which will provide a better insight into the epigenetics mechanism of heat stress in dairy cows.【Method】In the study, 24 Chinese Holstein lactation cows (Same lactation stage and same parity) in Sanyuan dairy farm were used for the blood samples collection in heat stress period (July in the summer of 2017 ) and non-heat stress period (April in spring 2017) respectively, followed by DNA extraction. To explore the DNA methylation differences in dairy cows from different heat stress period, 15 of 24 animals were randomly assigned to 3 groups (N=5 animals/group), 5 DNA samples in one group were mixed together to get a single pooled DNA sample, thus 6 pooled DNA samples including 3 from spring and 3 from summer were used for the DNA methylation detection by the Whole-genome bisulfite sequencing (WGBS), then differential methylation region (DMR; 1000 bp windows, 500 bp overlap, P<0.05) and key gene were identified. PROMO and Methprimer software were used to predict transcription factor binding sites and CpG islands, respectively. Then, the bovine mammary gland epithelial cells (Mac-T) were treated at 39 ℃ for 24 h, 48 h, 72 h, and the cell viability were detected by MTT method. Finally, using the bisulfite sequencing PCR (BSP), we examined the methylation levels of target gene promoter in 24 dairy cows in spring and summer respectively and Mac-T cells treated in 39 ℃.【Result】Based on the DNA methylation analysis of WGBS data, 49,861 differential methylation regions (DMRs) associated with heat stress were identified. One of DMRs was attributed to the promoter area of GNAS complex locus (GNAS), whose methylation level significantly increased in heat-stressed animals (P<0.001). Also, there is a 352bp CpG island in the promoter of GNAS containing potential binding sites for Sp1, C/EBP and other important transcription factors. Further the methylation status of the GNAS gene promoter region in heat stressed dairy cows were verified by BSP, and the average methylation level in all cytosine of 31 CpG sites was higher in heat stress cows than in control groups (P<0.05), which corresponding to the above WGBS results. Moreover, the 21 (-113 bp, Chr13:57532733) and 27 (-63 bp, Chr13:57532683) CpG sites showed significant differences between the spring and summer groups (P<0.05). In Mac-T cells, after 48 h and 72 h heat treatment, the cell viability decreased significantly (P<0.01), but the overall CG methylation level of 31 CpG sites in the GNAS gene promoter region increased significantly (P<0.05), also the similar significant methylation changes appeared in the site 21 and 27 CpG in cell.【Conclusion】Heat stress increased the methylation levels of the promoter region of the GNAS gene in dairy cows as well as in cells, which indicated that GNAS is a potential target gene regulated DNA methylation in heat stress response of dairy cows.


]]> <![CDATA[Isolation and Pathogenicity of Fowl Adenovirus Serotype 8a Strain]]> 】 Fowl adenovirus (FAdV) circulates in chicken flocks with multiple serotypes, while there is less information about the pathogenicity of all serotype strains. To understand the capability of causing disease as a primary pathogen to chicken of the FAdV-8a strain, we carry out the experiment for evaluating the pathogenic characteristics of this serotype strain, which will help making the control strategy for breeding. 【Method】 In 2017, liver tissue was collected form the diseased flocks. The liver tissue homogenates were inoculated into the embryo egg for isolating the virus. The isolate was determined as a FAdV strain after PCR detection. To classify the isolate, genomic sequencing and the genetic evolution based on the complete genome sequence and the hexon gene sequence were performed. To clarify the pathogenicity, thirty 10-day-old SPF chicks were randomly divided into 2 groups and exposed to the isolate JL/170408 via nasal inhalation and eye droppings. The clinical syndrome (including morbidity and mortality), viremia, virus shedding, circulating antibody, postmortem examination and histopathological detection at 5 days post infection (d.p.i.), viral distribution and the tropism on tissues were performed to evaluate the pathogenic capability and characteristics of JL/170408 to SPF chicks. 【Result】 The complete genome sequencing showed that there were the highest identity between the isolate and the FAdV-8a TR59 strain. They showed high identity in the genomic structure and the encoding gene. Phylogenetic analysis based on the complete genome sequence, the isolate JL/170408 was in the cluster of FAdV-E, further was grouped into the branch of serotype 8a based on the hexon gene. Consequently, the isolate JL/170408 was determined as FAdV-8a serotype within the species of FAdV-E. The clinical peak was observed from 3 to 13d.p.i. without death. The virus shedding and viremia was detected as early as 3d.p.i. and last for a long period at least 51d, the antibody was not positive conversion completely and the mean ELISA titer S/P<1, which didn’t provide enough neutralizing ability to eliminate the virus in the blood and the intestinal tract. At 54d.p.i., the ELISA titer reached a peak with a mean S/P>2, with the consequence of viremia disappearing and a sudden drop of virus shedding. Postmortem examination and histopathological detection at 5d.p.i. showed no obvious pathologic change. While the viral load was detected in 15 tissues, suggested that the isolate propagated in multiple tissues and exhibited higher tropism to gizzard. By monitoring the circulating antibody, the infected birds showed later antibody positive conversion until 15d post infection. Not all birds showed positive seroconversion even at 51d post infection, and the antibody level was stable. At 54d post infection, the antibody titer reached peak, suggesting that birds may suffer a second infection. Virus neutralization test based on the antiserum of 63d.p.i. showed that there was no obvious correlation between the circulating antibody and the neutralization antibody. 【Conclusion】 The FAdV-8a strain JL/170408 causes disease to 10-day-old chicks as single pathogen without leading to death, the isolate is determined as low pathogenic strain. JL/170408 propagates in multiple tissues with higher tropism to gizzard. The infected chicks show a long duration of virus shedding with a repetitive characteristics.


]]> <![CDATA[Establishment of a Canine Experimental Infection Model with a H3N2 Subtype Canine Influenza Virus]]> Objective】 In this research, an experimental animal infection model of canine influenza virus (CIV, H3N2 subtype) was established to better understand the pathogenesis of canine influenza and to lay the foundation for vaccine efficacy evaluation. 【Methods】 26 beagles aged 6-13 months with negative CIV Haemagglutination Inhibition (HI) antibody (HI < 1:10) were selected. Three were challenged by 1mL nasal spray of PBS. And twenty-three challenged by 1mL nasal spray of H3N2 CIV (A/canine/China/Huabei-170607/2017(H3N2), HB strain for short) with 5 groups (10、103、105、106、107 50% EID50) as 3, 5, 5, 5 and 5 beagles each group respectively. Clinical symptoms, lung lesions, histopathological changes of lung, calculating the proportion of consolidation mass, HI antibody titer and virus shedding were examined 14 days after virus challenge together with three control beagles. 【Results】 3 beagles inoculated with a dose of 10 EID50 H3N2 CIV did not show any clinical symptoms , gross lesions in lungs and histopathological changes. The consolidation rate was 0%. Virus shedding was not detected. The geometric mean titer (GMT) of HI antibodies was 1:15.9. However, 4/5 of beagles inoculated with a dose of 103 EID50 H3N2 CIV showed clinical symptoms and virus shedding such as puffing, runny nose and cough. 2/5 of beagles showed light lung consolidation, whose rate was 1.4%. The GMT of HI antibodies was 1:320. All beagles (5/5) infected with a dose of 105 EID50 H3N2 CIV showed clinical symptoms at day 5 after challenge such as runny nose and cough, virus shedding, lung consolidation and widened alveolar septum. The consolidation rate was 4.2%. The GMT of HI antibodies was 1:2940.7. 5/5 of beagles infected with a dose of 106 EID50 all showed severe clinical symptoms at day 4 after challenge such as cough and elevated body temperature, virus shedding, obvious pathological features in the lungs with GMT of HI antibodies were 1:2228.7. The clinical symptoms appeared earlier 1 day than that in 105 EID50 dose infection group. And the degree of lung consolidation increased. The lung consolidation ratio was 17.9%. 5/5 of beagles infected with doses of 107 EID50 all showed severe clinical symptoms at day 3 after challenge which appeared earlier 1 day than that in 106 EID50 dose infection group, virus shedding and widened alveolar septum in the lungs with GMT of HI antibodies were 1:2228.7. The consolidation rate of lung was 29.0%. Control beagles did not show any clinical symptoms, gross lesions and histopathological changes in lungs. And virus shedding was not detected. GMT of HI antibodies was ＜1:10. 【Conclusions】 The dose of 106 EID50 is the minimum virus inoculation dose that can cause obvious pathogenesis in beagles. An experimental animal infection model of CIV subtype H3N2 in beagles was established.


]]> <![CDATA[Effect of <span>L</span>itter <span>B</span>ed on <span>G</span>rowth <span>P</span>erformance and <span>O</span>dor <span>E</span>mission in <span>T</span>attening <span>L</span>amb #br#]]> 】 In view of the problem of odor non-point source pollution in fattening area of mutton sheep in recent years, the effects of bedding bed on growth performance of fattening lambs and odor components in the house were discussed, which provided a technical path for odor emission reduction in fattening sheep house.【Method】The purpose of the experiment was to investigate the effect of litter bed on growth performance in fattening lambs and odor components in lamb barn. Two-hundred fifty healthy fattening lambs with similar weight and age were used and randomly divided into 5 groups according to different bedding materials, which were control group (plain soil), group A (full-sawdust), and group B (furfural + sawdust), C group (rice husk + sawdust), and D group (corn cob + sawdust). The trial period was 90 days (d 1-45 in early period; d 46-90 in late period). The odor components in environment above and inside the litter bed were detected using GC-MS method during different periods, and the effect of litter bed on production performance in fattening lambs was also analyzed. 【Result】The results showed that: (1) Compared with the control group, the four groups with litter bed demonstrated an increase in daily feed intake (P < 0.05), increased by 7.7 % in group A and 8.7 % in Group B, 12.1 % in Group C, and 7.8 % in Group D. However, the daily gain and ratio of feed to gain exhibited no difference (P > 0.05). (2) Nine kinds and eight kinds of odor components were detected throughout test period above litter bed and inside litter bed, respectively, and the components consisted of 31 kinds of volatile organic compounds (VOCs) including 4 alcohols, 10 alkanes, 3 amines, 1 phenol, 7 esters, 4 ketones, 2 aldehydes, 3 acids, and 1 thiol. The odor kinds detected in 4 litter groups were basically same as the control group. (3) From content analysis of odor components, the alkane content was the highest with 52.0 %~77.5 % among all odor components, no matter experimental period or detected space; however, no difference was observed among all groups (P > 0.05). Also, the content of phenol or amine in litter groups demonstrated a decrease (P < 0.05) in two detected spaces in early and late periods, compared with the control, exhibiting the decrease in group C was obvious. Besides, the content of alcohol, amine, or phenol was higher (P < 0.05) in early period than that in late period both upper and inner spaces of litter bed; however, the ester content in late period was higher (P < 0.05) than that in early period. (4) During entire experimental period, four kinds of key odor-causing substances were detected both in upper and inner of litter bed, including 2-ethylhexanol, N,N-dimethylacetamide, phenol, and 1 H-indole-3-thiol. For the contents of the four odor-causing components, each litter group showed a decreasing trend, compared with the control group and the decrease in group C was the most obvious (P < 0.05). 【Conclusion】In summary, four combined litter beds in this study could improve growth performance in fattening lambs, and decrease odor content in environment. The results would provide a technical pathway for reduction of odor emission in sheep barn.


]]> <![CDATA[Risk Zoning of Heat Stress Risk Zoning of Dairy Cows in Jiangsu Province and its Characteristics Affected by Climate Change]]> 】In order to optimize the production management of pasture and promote ecological and healthy breeding level of dairy cows, mastering the occurrence law of cow heat stress under the background of climate change could provide reference for optimizing the layout of animal husbandry, intelligent management and control of pasture, site selection and transformation, benefit improvement and so on. 【Method】Taking Jiangsu Province as an example, using the Era5 data set of global atmospheric reanalysis data from 1980 to 2020, the risk index (RI) was constructed based on the temperature humidity index (THI), which represents the degree of cow heat stress. The K-means clustering algorithm was selected to realize the risk zoning of heat stress of dairy cows, and the regional evaluation was carried out in combination with the characteristics of occurrence intensity, frequency, start and end time, as well as duration of heat stress. The climate tendency rate was calculated to analyze the change trend of the characteristics of cow heat stress in different risk areas. Based on the cumulative temperature humidity index (CTHI), Mann-Kendall test was used to determine the climate mutation points in different risk areas. Furthermore, the impacts of climate change on the occurrence characteristics of cow heat stress in different risk areas were analyzed from the daily and hourly time scales, respectively. 【Result】The study showed that the risk of heat stress of dairy cows in Jiangsu Province presented the distribution features of "high in the southwest and low in the northeast". The low-risk areas mainly included Huaibei and the middle-eastern area of Yangtze river and Huai river valley. The regional averaged value of THI was 73.63, and mild heat stress mainly occurred. The high-risk areas mainly include the areas along the southern Jiangsu and the west area of Yangtze river and Huai river valley. The regional averaged value of THI was 75.12, and the occurrence frequency of mild and moderate thermal stress was nearly the same. In the low-risk and high-risk areas, the start and end time of heat stress showed an advanced and delay trend, and the duration days showed an extended trend of 4.0 d/(10a) and 4.2 d/(10a) respectively, the values of THI all showed an increasing trend of 0.2/(10a),while the value of CTHI showed an increasing trend of 301.2/(10a) and 256.1/(10a) respectively. The frequencies of mild thermal stress were bimodal, mainly occurred from the early-June to the mid-July, and from the early-August to the middle-September, while the frequency of moderate thermal stress was unimodal, mainly occurred from mid-July to mid-August. The change of daily heat stress intensity basically presented a distribution of "sinusoidal", and the high incidence period was concentrated in 11:00-17:00. Affected by climate change, the heat stress of dairy cows in Jiangsu Province showed an obvious increasing trend, reaching a small peak in 2010. Then after a decline, it showed a steady strengthening trend, which exceeded the threshold of 0.05 significance level. In low and high risk areas, the highly impacted periods of cow heat stress were prolonged, the occurrence frequency increased, the coverage increased and the starting-time moved forward. The daily beginning time of the high incidence period of cow heat stress moved forward for about 1 hour, and the intensity of heat stress in high-risk areas was basically increased close to the medium level. 【Conclusion】Based on THI, RI and CTHI, the risk zoning assessment and climate impact analysis of cow heat stress could be realized, the high-risk areas, and key prevention and control periods of cow heat stress could be determined, and the climate change trend could be grasped. With the climate change, the heat stress of dairy cows in Jiangsu Province shows the characteristics of "earlier, stronger, longer and more", which should be actively dealt with.


]]> <![CDATA[Isolation and <span>Geno</span>typing of <i>Mycobacterium avium</i><i> </i>subsp. <i>paratuberculosis</i> from S<span>heep</span> in Inner Mongolia #br#]]> 】 Paratuberculosis is listed in the must-report at the list of OIE diseases, infections and Invasion by the World Organization for Animal Health (OIE). It is classified as the second kind of animal disease in China. It causes chronic and proliferative enteritis in many ruminants. Infected animals become a continuous source of infection in farms through intestinal intermittent excretion, which has brought great economic losses to aquaculture. The pathogen of Mycobacterium avium subsp. paratuberculosis (MAP) belongs to intracellular parasitic Gram-positive bacteria, and is a third group of zoological pathogenic microorganisms, including type C (also designated as type II) and type S. Type C also includes type B. Type S can be further subdivided into sub-group types I and III. And sub-lineages of camelid isolates Studies have shown that each subtype of MAP has no host specificity, but is regional. Inner Mongolia is the first region of the disease in China. It is of great significance to obtain and accurately identify the subtype and genetic characteristics of MAP strains in Inner Mongolia for the prevention and control of paratuberculosis. 【Method】 28 MAP-positive sheep disease samples collected in Inner Mongolia were isolated and cultured by MAP, and the colonies were stained with Ziehl-Neelsen. The positive bacteria were propagated and the genomic DNA was extracted. IS900 gene, IS1311 gene and DMC gene were amplified, sequenced and analyzed. The PCR products of IS1311 gene were identified by Hinf I and Mse I double digestion. 【Result】 28 samples were cultured for 7 - 12 weeks, a total of 9 mediums grew colonies, the colonies were translucent milky white, smooth surface. Single colonies were selected for acid-fast staining, and irregular (single or branched), red-stained Brevibacterium was observed under the microscope, which was consistent with the morphological characteristics and acid-fast staining characteristics of Mycobacterium. The PCR products of IS900, IS1311 and DMC genes of 9 isolates were consistent with the expected size of the target gene fragment. 9 isolates were identified as MAP strains, named MAP-NM1 to MAP-NM9. DMC gene amplification product size of 310bp, consistent with type II MAP characteristics. IS1311 gene amplification products were digested by Hinf I and Mse I restriction endonucleases, and 4 target bands were obtained in 9 strains of MAP, which were consistent with type II MAP. The sequencing results of IS1311 gene and the analysis of MAP representative strains of type I, type II, type III, Indian Buffalo and American Buffalo showed that the nucleotide sites at positions 64, 65, 68, 223, 236, 422, 527 and 628 of the nine MAP IS1311 gene fragments conformed to the characteristics of type C and type B MAP. Sequence analysis of IS900 gene sequencing results showed that the 169th and 216th nucleotides of the nine MAP IS900 gene fragments were C (cytosine) and A (adenine), and accord with Type II and type III MAP. The phylogenetic tree of 17 MAP IS900 gene reference sequences from GenBank database with 9 isolates in this study showed that the 9 isolates in this study were all in the type II MAP branch. Blast online analysis was performed on the sequencing results of the three genes. The reference sequences with the highest homology with the isolates obtained in this study were all type II MAP, and the homology was higher than 98%. In conclusion, all the 9 MAP isolates were type II MAP. 【Conclusion】 To the best of our knowledge, this is the first isolate of the MAP type Ⅱ strains in sheep in Inner Mongolia. 


]]> <![CDATA[Genome-wide Association Studies for Grape Berry Weight Related Traits]]> 】Grape berry size is one of important factors affecting grape appearance and the final productivity. It is a complex quantitative trait regulated by multiple genes. Mining the key genetic regulatory loci and the underlying genes for berry size related traits will help to improve grape yield. 【Method】In this study, 150 diverse grapevine varieties were selected as materials. The berry weight, seed number per berry, and seed weight were measured in 2019 and 2020, respectively. Based on high-density genotype data obtained by resequencing, the genome-wide association studies (GWAS) were carried out to detect significantly associated SNPs and predict important candidate genes.【Result】The three measured traits exhibited extensive phenotypic variation with 39.55%-68.89% of phenotypic variation coefficients; The phenotypic distribution of the observed three traits in the population showed continuous quantitative genetic characteristics; A significant positive correlation between each trait were observed in two years; Based on the phenotypic data collected in two years, a total of 150 significant SNPs were detected for berry weight. In 2019, 99 SNPs were detected, each of which contributed the phenotypic variation from 14.48% to 25.59%; In 2020, 73 SNPs were detected, explaining 16.08%-26.83% of phenotypic variation; Among these SNPs, 24 were detected repeatedly in both two years, mainly located on chromosome 1, 5, 11 and 16. Compared with the trait of berry weight, less SNPs significantly associated with the seed number were detected. A significant SNP was detected in 2019, and the phenotypic explanation value was 24.29%; In 2020, 17 significant SNPs were detected, which all located on chromosome 18; 1 and 2 SNPs located on chromosome 18 significantly associated with seed weight were detected respectively in 2019 and 2020, accounting for 23.59%-48.29% of phenotypic variation. Within the genomic region of SNPs detected repeatedly for two years, 11 candidate genes that may be related to berry weight were screened out based on the functional annotation, including ethylene signal pathway genes (VIT_05s0049g00490, VIT_05s0049g00500, VIT_05s0049g00510 and VIT_16s0100g00400), gibberellin signal pathway genes (VIT_11s0016g04630 and VIT_16s0022g02310), auxin responsive protein gene (VIT_11s0016g05640) and some important transcription factor genes (VIT_05s0049g00460, VIT_11s0016g05660 and VIT_16s0022g02330). A candidate gene VIT_18s0041g01880 (encoding a MADS box protein VviAGL11) associated with seed content was identified on chromosome 18, and different SNP genotype on this gene significantly affected the grape berry seed number and weight. 【Conclusion】A total of 150 SNPs significantly associated with berry weight were detected in two years, mainly located on chromosomes 1, 5, 11 and 16; A total of 19 significant SNPs associated with seed content were detected, mainly located on chromosome 18. Based on the results of gene annotation and genotype analysis, 11 candidate genes that may be involved in the regulation of grape berry weight including VIT_11s0016g04630 and VIT_16s0022g02310 were selected; the candidate gene VIT_18s0041g01880 was determined significantly correlated with seed content.


]]> <![CDATA[Identification and Comparative Analysis of Metabolites in Grape Seed Based on Widely Targeted Metabolomics]]> 】Grape seeds have high bioactivity because they are rich in many metabolites. The objective of this study is to comprehensively identify the metabolite components in grape seeds, compare and analyze the differences of metabolites among different varieties, and explore the relationship between metabolites in grape seeds and skin color and variety origin, so as to provide a reference basis for further development and utilization of grape seeds. 【Method】The mature seeds of purple-skinned Kyoho (V. labruscana: V. labrusca × V. vinifera, JFS), pink-skinned Wink (V. vinifera, WKS), and yellow-skinned Italia (V. vinifera, YDS) were used for widely targeted metabolomics analysis by UPLC-MS/MS. The metabolites were identified and compared by multivariate statistical methods. 【Result】The quality of metabolomics data was good; the data of samples within groups was repetitive and the differences in the data of samples among groups were existed. A total of 514 metabolites were identified in the seeds of three grape varieties, including 6 primary metabolites such as amino acids and lipids and 20 secondary metabolites such as proanthocyanidins and resveratrol. Among different varieties, the metabolite components were similar but the metabolite contents were significantly different. The relative contents of most metabolites were high in the dark variety Kyoho, followed by the light variety Wink, but low in the colorless variety Italy, indicating that the metabolite contents in grape seeds may be positively correlated with the skin color. The relative contents of metabolites in the seeds of Wink and Italia were similar, while they were greatly different from those of Kyoho, indicating that the metabolite contents in grape seeds may be related to the variety origin. The differential metabolites among different varieties were mainly involved in phenylpropane biosynthesis, anthocyanin synthesis, lipid metabolism, etc. pathway. There were many phenolic compounds in the differential metabolites and the metabolites with the large difference were mainly flavonoids. Grape seeds are rich in phenols and lipids. In addition to monomeric flavane-3-ols and their polymers, the relative contents of other phenolic compounds such as flavones and flavonols are also high. There was no significant difference in the relative contents of resveratrol among the three varieties. The relative contents of glyceryl phosphatide such as lysophosphatidylcholine were high, while those of linolenic acid were low. There was little difference in the relative contents of lipids among different varieties. 【Conclusion】The metabolite components  in grape seeds of different varieties were similar, while the metabolite contents were related to the skin color and the variety origin. Phenols and lipids are important components of metabolites in grape seeds and can be used as good sources for food and other processing industries.


]]> <![CDATA[Determination and Analysis of Flavonoids Metabolites in Different Colors Cultivars and Blooming Stages of <i>Prunus mume</i> #br#]]> 】Flower color is an extremely important ornamental trait of P. mume, and flavonoids are the main pigments in the petals of P. mume. However, there are few systematic studies on the composition of flavonoids, and the relationship between flower color and flavonoids in P. mume. The study on flavonoids can provide reference for the mechanism of flower color formation and the development of flavonoids resources in P. mume.【Method】In this study, the petals of four P. mume cultivars with representative flower color in the blooming stage and the key period of flower color change of two cultivars were selected as materials. It measured the flower color phenotype of petals with the Royal Horticultural Society Color Card (RHSCC) and colorimeter. Flavonoids in those petals of flowers were determined by high-performance liquid chromatography and mass spectrometric (HPLC-MS) detectors. Then, Duncan test and OPLS-DA were used to analyze the difference of metabolites among these four cultivars and the major blooming stages. 【Result】In total, 25 flavonoids were described. The main components of  red Baixu Zhusha and purple-red Huqiu Wanfen wereanthocyanins. But the contents of cyanidin and its derivatives between Baixu Zhusha and Huqiu Wanfen were differences. In addition, from the big budding stage to the blooming stage, the red color of Baixu Zhusha gradually became lighter, and the contents of cyanidin-3-O-glucoside and peonidin -3-O-glucoside also gradually decreased.Yellow-green Bian Lv’e and pure white Sanlun Yudie were most enriched with quercetin and its derivatives. The contents of quercetin derivatives between Bian Lv’e and Sanlun Yudie were differences. 【Conclusion】The flavonoid metabolic profiles differed among the different colored petal, and flavonoids with medicinal value were distributed in all varieties. The difference in the contents of cyanidin and peonidin may be related to  petal color differences of red P. mume. Quercetin derivatives may affect the color of yellow-green P. mume. In this study, the flavonoids metabolites of different color P. mume were identified and analyzed for the first time, and the differences in flower color P. mume varieties and the blooming process were preliminarily understood from the metabolic level. The results provide a reference for understanding the difference of flower color formation and development of flavonoid resources of P. mume. 


]]> <![CDATA[Comprehensive Fruit Quality Evaluation and Suitable Areas Selection of Newhall Navel Orange in China]]> in fruit quality, clarify the comprehensive grade of fruit quality and their corresponding meteorological characteristics from different Newhall Navel orange (Citrus sinensis [L.] Osb. cv. Newhall) orchards in China, and provide a reference for the ecological environment adaptability and suitable planting. 【Methods】Twenty three Newhall orchards in different ecological environments of China were selected to measure fruit external and internal quality indicators. Correlation analysis, principal component analysis and cluster analysis were used to identify the core indicators, and the comprehensive evaluation models of fruit quality were established by analytic hierarchy process (AHP), principal component analysis (PCA) and fuzzy comprehensive appraisal (FCA), respectively. The optimal algorithm model and fruit grade classification threshold were determined and verified with sensory quality evaluation. Meanwhile, the comprehensive quality grades 


and the characteristics of corresponding ecological factors of Newhall navel orange fruit from different producing areas were explored. 【Results】The fruit comprehensive quality of 23 Newhall orchards showed obvious regional characteristics. The fruit in southern Jiangxi and southern Hunan have higher total soluble solid and solid acid ratio, while the fruit in western Hunan and the upper and middle reaches of the Yangtze River have better fruit external color indexes and higher titratable acid. The quality indexes are correlated to varying degrees. Five core indexes were selected by principal component analysis combined with cluster analysis, including comprehensive color index, fruit weight, soluble solids, solid acid ratio and vitamin C content. At the same time, AHP model was determined as the comprehensive evaluation model of fruit quality with the best fitting degree of sensory quality index: Y (comprehensive value) = 0.06× comprehensive color index + 0.26× single fruit weight +0.16× soluble solid content +0.42× solid acid ratio +0.11× vitamin C content (standardized value). The comprehensive fruit quality indicators of different Newhall orchards were ranked, and the classification threshold was determined as follows: ≥0.60 was the first—class orchards, mainly concentrated in southern Jiangxi, southern Hunan and eastern Guangdong, with active accumulated temperature, effective accumulated temperature, maximum sunshine hours and surface temperature; 0.45—0.60 was the second—class orchards, mainly concentrated in northern Guangxi and western Fujian, characterized by higher temperature accumulation and rainfall; 0.30—0.45 was the third—class orchards, mainly concentrated in western Hunan and the middle and upper reaches of the Yangtze River, with relatively lower rainfall and temperature accumulation; <0.30 was the fourth—class orchards, mainly distributed in southern Zhejiang, with the highest rainfall. 【Conclusion】The core indicators of the comprehensive quality of citrus fruits were identified by PCA, and the AHP model with the optimal for the Newhall fruit comprehensive evaluation by combining the eigenvalues of each principal component to achieve automatic assignment of AHP judgment matrix. The ecological factors of different grades of orchards were significantly different. These results provide algorithms and data support for the development of the decision system based on " suitable planting "of citrus varieties in different ecological environment.

]]> <![CDATA[Current Status and Strategies for Utilization of Stripe Rust Resistance Genes in Wheat Breeding Program of China]]> Puccinia striiformis f. sp. tritici (Pst) is a devastating disease threaten food security in China and worldwide. Epidemics of wheat stripe rust have been under control through applying resistant cultivars and crop protection approaches. However, due to climate change, innovation of cropping system, improvement of breeding technology, yield level enhancement of wheat cultivars, variation in structure and frequency of virulence genes in Pst populations in the new Era, the current status of stripe rust resistance genes in wheat breeding programs need to be evaluated. The results could provide useful information for applying stripe rust resistance genes to develop new wheat cultivars with broad-spectrum and durable rust resistance. After multiple year’s stripe rust resistance survey, genetic analysis, molecular tagging and mining of stripe rust resistance genes in wheat cultivars and advanced breeding lines, the current status of major stripe rust resistance genes utilization was reviewed. We summarized the present situations of major stripe rust resistance gene discovery and germplasm innovation, the most frequently used stripe rust resistance genes, new strategy for pyramiding adult plant partial resistance and all stage resistance, and molecular marker assisted selection for developing wheat cultivars with broad spectrum and durable resistance in China. This review also proposes the major research areas in wheat stripe rust resistance breeding in the New Era.


]]> <![CDATA[Comprehensive evaluation and breeding evolution of early maturing upland cotton varieties in the northwest inland of China]]> 】This paper evaluated comprehensively early maturity upland cotton varieties in northwest inland cotton-growing region of China, and uncovered the evolution rules of the main traits from the breeding cultivars in the region. It provides a useful reference for recommendation and breeding of main cotton varieties in northwest inland region. 【Method】A total of 110 early-maturing upland cotton varieties which were approved in northwest inland cotton-growing region from 1988 to 2021 were applied, and phenotypic identification of 12 main traits related to early maturity, yield, fiber quality and plant architecture was carried out in Dunhuang, Gansu province and Shihezi, Xinjiang production and construction corps in 2020 and 2021, respectively. Clustering analysis, correlation analysis and principal component analysis were respectively used to evaluate the phenotypic characteristics of the cultivars, and carry out the breeding evolution analysis of their main traits. 【Result】The phenotype value of 12 main traits had large distribution range from 110 early-maturing upland cotton varieties in northwest inland cotton-growing region of China. The variation coefficient in descending order is: fruit branch length (FBL), boll number per plant (BN), boll opening rate (BOR), boll weight (BW), fiber micronaire (FM), fiber strength (FS), lint percentage (LP), fiber length (FL), flowering time (FT), fruit branch angle (FBA), fiber elongation (FE), and fiber uniformity (FU). By cluster analysis, these cultivars were divided into four groups: Ⅰ, Ⅱ, Ⅲ and Ⅳ, which were the population of high fiber quality, early maturity, loose plant type and high yield, respectively. Correlation analysis showed that early maturity was negatively correlated with yield and fiber quality related to traits, while the yield related to traits were positively correlated with the fiber quality traits, and most of them reached significant or extremely significant level. The 12 main traits were simplified into four principal components which had cumulative contribution rate of 66.92%. Based on the comprehensive evaluation results of these varieties by principal components, an excellent cultivar Zhongmian 113 ranked the first in the 110 early-maturing upland cotton varieties with a score of 0.67, which was characterized by early maturity, high yield and excellent fiber quality, and relatively loose plant type. Additionally, it was found that the early maturity character of cotton varieties approved in Gansu province was significantly better than that of varieties approved in northwest inland region and Xinjiang province, and the traits related to yield and fiber quality of cotton varieties approved in Gansu province were significantly lower than those of varieties approved in northwest inland region and Xinjiang province. During the breeding evolution of early maturing upland cotton varieties in northwest of China for more than 30 years, most of the traits related to yield and fiber quality showed significant upward trends, and the plant type was becoming more compact. BN was negatively correlated with BW, LP, FL and FS in early cultivars, while BN was positively correlated with BW, LP, FL and FS in recent cultivars.【Conclusion】In the process of breeding and improvement of early maturing upland cotton varieties in northwest of China, the main traits related to yield and fiber quality had wide distribution, and they had significant improvement trends year by year. In the recently developed varieties, BN, FL and FS had been improved cooperatively. 


]]> <![CDATA[Construction of A Comprehensive Evaluation System and Screening of Cold Tolerance Indicators for Cold Tolerance of Cotton during Seeding Stage #br#]]> to test hypocotyl length, root length and 100-grain weight, etc. under three treatments of constant chilling (CC), diurnal variation of chilling (DVC) and normal conditions. A combination of integrated cold tolerance coefficient difference analysis, frequency analysis, drop analysis, principal component analysis, cluster analysis, and multiple regression analysis were used to classify their cold tolerance types, establish cold tolerance prediction models, and screen evaluation parameters. 【Result】The variation of each parameters at normal conditions were minor fluctuations ranging from 3.12% to 18.89%. The seedling emergence rate was above 85.00%, which had high viability and could be used for subsequent cold tolerance analysis. The variability of each parameters within the accessions increased under chilling stress, ranging from 7.14%-108.33%, and the most variable parameter were root length under CC condition and germination index under DVC condition. Principal component analysis converted the 14 parameters under chilling stress and 100-grain weight measured into six mutually independent composite indicators, representing 74.98% of the total data information. The comprehensive cold tolerance evaluation value (D) was calculated by the affiliation function method and then clustering analysis was performed. 200 cotton varieties (lines) were divided into five categories according to their cold tolerance, with 2 of the group Ⅰ being strongly cold tolerant, 42 of the group Ⅱ being cold tolerant, 69 of the group Ⅲ being medium cold tolerant, 83 of the group Ⅳ being more sensitive, and 4 of the group Ⅴ being sensitive, of which Xinluzhong 16 was the most cold-tolerant material. A multiple regression analysis was applied to establish a prediction model for cold tolerance of cotton at seedling emergence as Y=-4.10+0.58X4+0.40X14+0.32X1+0.22X5 (R2=0.92), and four parameters for cold resistance evaluation were confirmed, namely total length, emergence rate, and dry matter weight under CC stress, germination rate under DVC stress. The cold-tolerant varieties (lines) had higher seedling emergence rates of early sowing experiment in the field, which were basically consistent with the results of the indoor results. 【Conclusion】It is feasible to use CC and DVC stress combined with multivariate statistical analysis to evaluate the cold tolerance of cotton at seeding stage, and total length, emergence rate, and dry matter weight under CC stress, germination rate under DVC stress can be used as evaluation parameters.


]]> <![CDATA[Functional Analysis of <i>AhNRT2.7a </i>in<i> </i>Response to Low-Nitrogen in Peanut #br#]]> Objective】Nitrogen (N) plays a key role in determining biomass and yield in crop production. NRT2s, the high affinity nitrate transporter genes, are mainly activated under low nitrogen stress condition and have been implicated in nitrate absorption and remobilization. This study will screen NRT2 gene family responding to low-nitrogen condition (1/20 of the normal level) and conduct a preliminary functional analysis of AhNRT2.7a in order to provide target genes for breeding new peanut varieties with higher nitrogen utilization efficiency (NUE)，which will help to achieve the goal of to improve crop production with less N fertilizer demand and environmental degradation. 【Method】The spatio-temporal expression patterns under normal and low-nitrogen conditions of five peanut NRT2 genes, AhNRT2.4, AhNRT2.5b, AhNRT2.5c, AhNRT2.7a and AhNRT2.7b, were investigated. Using the cDNA of Huayu6309 as template, full length of AhNRT2.7a CDS was cloned and bioinformatic analyzed. Subcellular localization of AhNRT2.7a was conducted by construction of transient expression vector and transformation of Arabidopsis protoplasts. In order to explore the gene function of AhNRT2.7a, heterologous overexpression of the AhNRT2.7a gene in Arabidopsis were performed. Transgenic plants were used to determine chlorophyll content, nitrogen accumulation and the enzymatic activities of glutamine synthetase (GS), glutamate synthetase (GOGAT), nitrate reductase (NR), nitrite reductase (NiR) and glutamate dehydrogenase (GDH) under normal and low-nitrogen conditions.【Result】Four NRT2 genes of peanut were highly expressed in response to low nitrogen stress, and AhNRT2.7a was highly expressed in the stems and leaves. The total length of 1 380 bp was obtained, encoding a 459-amino acid protein with a molecular weight of 49.35 kD. The total of 12 typical transmembrane protein domains with hydrophobic regions was predicted. Bioinformatics analysis showed that the amino acid sequence had 99.56% sequence similarity with the cultivated peanut (Arachis hypogaea L.), followed by the wild-parents AA (A. duranensis) and BB (A. ipaensis). Subcellular localization analysis revealed that AhNRT2.7a was located in the cell membrane. Transgenic Arabidopsis plants for over-expressing AhNRT2.7a were conducted. Relative content of chlorophyll in mature and young leaves was significantly higher than that in wild-type Arabidopsis under different nitrogen supply. Meanwhile, the activity of five enzymes involved in nitrogen metabolism were examined. Furthermore, uptake, assimilation and re-mobilization of N, concentration of phosphorus and potassium were determined. The results have revealed that the activity of the two nitrogen metabolizing enzymes (NR and GS) and nitrogen accumulation in transgenic plants were significantly higher than in wild-type Arabidopsis.【Conclusion】These results indicated that AhNRT2.7a could enhance the nitrogen use efficiency (NUE) in plants, and also improve carbon metabolism. AhNRT2.7a seems promising as a candidate gene in breeding new peanut varieties with higher NUE.


]]> <![CDATA[Mapping and Analysis of QTL for Embryo Size-Related Traits in Tetraploid Wheat]]> 】This study is to excavate embryo-related quantitative trait loci (QTL) with potential breeding value, to explore the genetic relationship between embryo and other agronomic traits in tetraploid wheat, and finally to aim at laying an important foundation for the fine mapping and breeding utilization of embryo-related traits in the future.【Method】A total of 121 F8 recombinant inbred lines (RIL) constructed by crossing tetraploid durum wheat (Ailanmai) and wild emmer wheat (LM001) were used. This RIL population was planted in five different environments including Wenjiang (2018-2020), Chongzhou (2020), and Ya'an (2020) in Sichuan Province for phenotypic evaluation of embryo length (EL), embryo width (EW), embryo length/embryo width (EL/EW), embryo length/kernel length (EL/KL), embryo width/kernel width (EW/KW), and embryo area (EA). QTL mapping was performed based on a genetic linkage map constructed based on the wheat 55K SNP. 【Result】 The embryo size-related traits showed approximately normal distribution in the RIL population satisfying the genetic characteristics of quantitative traits. A total of 27 QTL for embryo size-related traits were detected in five environments over three years. Among them, seven ones controlling EL could contribute 11.88 % to 18.99% of phenotypic variation. Seven QTLs controlling EW could explain 21.77 to 29.41% of phenotypic variation. Five stable and major QTLs (QEL.sicau-AM-3B, QEW.sicau-AM-2B, QEW/KW.sicau-AM-2B, QEL/EW.sicau-AM-2B-1 and QEA.sicau-AM-2B) were identified, and they explained 11.88% to 18.99%, 21.77% to 29.41%, 8.80% to 24.92%, 12.79% to 25.69% and 10.47% to 15.22% of phenotypic variation, respectively. In addition, four QTL-rich regions were identified in the embryo size-related loci mentioned above. The QTL controlling EL/KL and EL was located on chromosome 1B, that for EW, EL/EW, EW/KW, and EA was located on 2B, that controlling EL and EA was on 3B, and that controlling EL/EW and EW/KW was on 6B. Embryo size was significantly and positively correlated with kernel size. Further, the major QTL for EL, QEL.sicau-AM-3B was co-located with that for kernel length identified previously, but that for EW QEW.sicau-AM-2B was independent of that for kernel width. Four genes likely involved in regulation of embryo size were identified in intervals where major QTL were mapped. 【Conclusion】Five stable and major QTLs were identified: QEL.sicau-AM-3B, QEW.sicau-AM-2B, QEW/KW.sicau-AM-2B, QEL/EW.sicau-AM-2B-1, QEA.sicau-AM-2B, among which QEW.sicau-AM-2B may be novel.


]]> <![CDATA[Construction of High Density Genetic Map for RIL population and QTL Analysis of Heat Tolerance at Seedling Stage in Rice (<i>Oryza sativa</i> L.) #br#]]> 】With global warming, high temperature has an increasing impact on food crop safe. Excavation of heat tolerance gene resources is the most direct green ecological method to cultivate new varieties of heat resistance and eliminate the harm of high temperature, which also the basis for clarifying the physiological, biochemical and molecular genetic mechanism of heat tolerance.【Method】Establishing the identification and evaluation method of heat tolerance at seedling stage, a set of RIL populations was structured from the extreme heat-tolerance Ganzaoxian58(GZX58) and heat-sensitive Junambyeo (JNB), and then the high density genetic map was constructed using genotyping by resequencing technology. To converting SNP information into Bin genotype of the RIL population using sliding window method, which predicting the recombination breakpoints on the chromosomes, finally a high density BinMap genetic map was constructed. Based on the genotype and phenotype data of the 171 lines, QTL mapping of the high temperature seedling survival rate (HTSR) and heat tolerance class (HTC) was performed by ICIM method of the QTL IciMapping software.【Result】A high-density genetic map containing 3,321 Bin markers was constructed, the number of Bin markers for each chromosome between 159 and 400, the average physical distance two markers was about to 106 kb; heat tolerance of the parents and RIL populations was identified by stepwise heat stress at seedlings stage, there have a significant negative correlation between HTSR and HTC, in addition, there has a significant positive correlation between HTSR and indica gene frequency (Fi), which the higher of the Fi, the heat tolerance is better; the bi-modal continuous distribution of phenotype traits from the RIL population showed that the heat tolerance is regulated by few major QTL. A total of 12 QTL controlling with heat tolerance at seedling stage, there have 8 and 4 QTL regulating for HTSR and HTC, respectively. There has a significant genetic overlap from HTSR and HTC, qHTS2, qHTS7 and qHTS8, three major QTL cluster play an important role in regulating the heat tolerance at seedling stage. Among these QTL, qHTS7 was a novel major QTL cluster, which has a strong effect on enhancing the heat resistance at seedling stage. 【Conclusion】We constructed a high density genetic linkage map containing 3,321 Bin markers, which be used to analyzed the heat tolerance gene from the GZX58 at seedling stage, there have three key QTL cluster identified associated with the heat tolerance, a novel QTL cluster qHTS7 was discovered, efficient acquisition of target segments and candidate genes based on high-density genetic mapping, eight key candidate genes were selected by bioinformatics for regulation of the heat tolerance.


]]> <![CDATA[Study on lipase activity difference of oat varieties and prediction of low lipase activity variety with high quality]]> 】This study explored the differences and causes of oat lipase activity of different varieties. Providing a theoretical basis for screening varieties with low lipase activity and achieving stable enzyme inactivation effect of oat products. 【Method】Six main varieties of three main oat planting regions were selected for the study, and their lipase activity, nutritional indexes, physical traits, and agronomic indexes were measured. To answer the differences in lipase activity of oat varieties, the indicators significantly related to oat lipase were screened by correlation analysis. Through cluster analysis, classified multiple oat samples by lipase activity. Transform data having correlations into composite variables for statistical analysis by principal component analysis. To derive a predictive model for lipase activity, an analytical method combining gray correlation and multiple stepwise regression was used. The indicators correlating with lipase activity were used as independent variables, and the lipase activity was used as dependent variables for quantitative model fitting. 【Result】Lipase activity was significantly positively correlated with crude fat content (r=0.32, p<0.05), and the various trends of fat content, unsaturated fatty acid content, lipase activity, and acid value were consistent. Lipase activity was significantly positively correlated with crude protein content (r=0.46, p<0.01), and the higher lipase activity was, the higher percentage of electrophoretic bands located in 31-43 kD were. It was significantly negatively correlated with grain test weight (r=-0.71, p<0.01) and positively associated with growth period (r=0.37, p<0.01). Baiyan 18 and Diyan 1 were low lipase activity and high nutrition varieties according to grey relational analysis, and the relevance value with ideal variety X0 were 0.951 and 0.883, respectively. Stepwise regression analysis only retained the test weight and protein content as independent variables. The prediction model of lipase activity was established as Y=720.274－2.255×test weight (g·L-1)+75.761×protein content (%), p<0.01, R2 = 0.658.【Conclusion】The varieties had significant effects on oat lipase activity. Protein content, fat content, test weight, and growth period were the main influencing factors of oat lipase activity. Grey relational analysis combined with stepwise regression analysis could be used to comprehensively evaluate oat varieties effectively and quickly select varieties with low lipase activity.


]]> <![CDATA[Dynamic Changes of Gibberellin Content During the Development and It’s Relationship with Yield of <em>Brassica napus</em> L.]]> 】It was found that there were significant genetic differences between Chinese and European Brassica napus lines, and the yield advantage of hybrid F1 was obvious. To explore the effect of gibberellin (GA) on the growth and development of B. napus, the dynamic changes of GA during the developmental process of B. napus from different lines were measured. For explaining the role of GA in the formation of yield, the transcriptional levels of key enzyme genes involved in GA synthesis were analyzed, and the relationship between GA content and yield in parents and F1 was clarified.【Method】The dynamic changes of GA content in B. napus lines (15 Chinese lines and 15 European lines) with different sources from November 2020 to May 2021 were determined using high performance liquid chromatography. Two F1 hybrid lines (YG2009×YC4, ZS11×YC4) with strong heterosis and their parents were used as materials to investigate the changes of GA content in different periods (D1, 15 January 2022; D2, 15 February 2022; D3, 15 March 2022) and measure growth indicators (plant height, root length, fresh weight, etc.), yield and component factors (silique number per plant, seed number per silique and thousand-seed weight), as well as photosynthetic indicators (photosynthetic rate, stomatal conductance, transpiration rate and intercellular CO2 concentration). The change trend of GA content with temperature and the relationship between GA content and agronomic characters, photosynthetic characteristics and yield of parents and F1 hybrid from November 2021 to May 2022 were analyzed. Besides, the transcriptional levels of key enzyme genes involved in GA synthesis of the parents and F1 at different stages (D1, D2, D3) also examined by quantitative real-time PCR.【Result】The content of GA was closely related to the ambient temperature, and the GA content in the tested B. napus lines decreased first and then increased with the change of temperature. However, it was found that the average content of GA in B. napus lines from Europe was higher than that of Chinese lines. F1 showed significant yield heterosis. Compared with the male and female parents, the yield of YG2009×YC4 and ZS11×YC4 increased by 18.06% and 10.35%, and 29.92% and 28.6%, respectively. There were significant differences in agronomic traits between parents and F1, and the yield was correlated with GA content. The results also showed that the transcriptional levels of GA20ox4, GA3ox2 and SLR1 in parents and hybrid F1 varied greatly.【Conclusion】The GA content of B. napus lines from Europe was more sensitive to temperature changes, but its average content of GA was higher than that from China. The yield of F1 between European rape and Chinese rape lines showed strong heterosis, which was correlated with GA content. The transcriptional levels of GA20ox4 and GA3ox2 regulated the GA content.


]]> <![CDATA[Evaluation of Resistance to Leaf Scald Disease in Different Sugarcane Genotypes]]> 】Sugarcane leaf scald disease is an important bacterial disease affecting sugarcane yield. Selection of disease-resistant genotypes can effectively reduce the incidence of this disease. This study aimed to explore the leaf-scald resistance of sugarcane genotypes, standardize resistance evaluation method, and provide a basis for the selection and utilization of germplasm resources of sugarcane. 【Method】Xanthomonas albilineans JG43 isolated from Guitang 46, was used as inoculum on 70 sugarcane genotypes using the decapitation method by placing 500 mL of bacterial suspension on the surface previously cut above the apical meristem with scissors dipped in the inoculum suspension of 108 CFU/mL. The disease incidence (IC) was calculated at 14, 28, 42, 56, and 70 days post-inoculation (Dpi). The disease index (DI) and the area under the disease progress curve (AUDPC) were calculated according to the disease severity of leaf scald in sugarcane. Variance, principal component, and discriminant analysis were performed using SPSS 25.0 software. Among them, a general linear model procedure (PROC) and the square sum model of type III were used to analyze the variance, with IC, DI and AUDPC as dependent variables, genotype, block and days post-inoculation as fixed factors. After the original data were processed by standardization (Z-score), principal component analysis was carried out by KOM and Bartlett sphere test. The Euclidean metric was calculated for cluster analysis using the WPGMA method of DPS 9.50 software. The discriminant analysis was performed to evaluate the clustering results according to Fisher's criterion. 【Result】Some genotypes displayed white pencil lines at 14 dpi, then gradually expanded to the edge at 28 dpi. The leaves began yellowing or albinism from the edge to the veins at 42 dpi, then curled inward and died at 56 dpi. The severely infected plant withered and eventually died at 70 dpi. Variance analysis exhibited highly significant effects for IC, DI, and AUDPC among genotype (Gen), days post-inoculation (Dpi), and their interactions effect (Gen × Dpi) (P<0.01). Approximately 42% of the total sum of square was attributed to Dpi effect, followed by Gen × Dpi and Gen effects, indicating significant differences among genotypes resistance across the days post-inoculation. At 56 dpi, the disease reached a steady plateau, and the data in this period could be better divided among sugarcane genotypes. The results of discriminant and cluster analysis showed that 70 genotypes were divided into five different groups, including 15 highly resistant, 14 resistant, 15 moderate, 11 susceptible, and 15 highly susceptible genotypes. 【Conclusion】The resistance of sugarcane genotypes to leaf scald was assessed using the decapitation method, the IC, DI and AUDPC at 56 dpi were used as the evaluation indicators. The combined method of clustering and discriminant analysis could improve the accuracy of clustering results. Fifteen genotypes of high resistance to leaf scald were assessed and used for the sugarcane breeding program in China, including Zhongzhe 9, Zhongzhe 4, Zhongzhe 2, GUC19, GUC8, Yunrui 03-103, Yunrui 05-649, Yunrui 05-182, Yunrui 05-367, Yunrui 89-159, Funong 11601, Funong 09-4059, Guitang 02-467, Guitang 08-297, ROC22.


]]> <![CDATA[Screening of Core Markers and Construction of DNA Fingerprints of Semi-waxy <em>Japonica</em> Rice Varieties]]> 】A set of variety DNA fingerprint identification system based on the core markers of genes regulating rice important traits was constructed, which will establish a foundation for strengthening the germplasm management and protection of the mainly promoted semi-waxy japonica rice varieties with high eating quality,【Method】34 semi-waxy japonica rice varieties mainly cultivated in Jiangsu, Zhejiang and Shanghai were used as the test materials. The key differential sequence sites in genes regulating rice important traits were screened and core SNP or InDel markers were developed through multiple methods such as polymorphism testing of existing markers, gene sequence alignment from public databases and genome resequencing. SNP markers were developed into simple PCR markers based on electrophoretic bands by As-PCR technology. Genotype information was obtained by electrophoretic band characterization and type analysis, and the DNA fingerprint database of the semi-waxy japonica rice varieties was constructed. 【Result】 54 core markers derived from 40 key genes regulating rice important traits were obtained, including 18 SNP and 36 InDel markers; 155 characteristic and effective bands were identified by 54 markers in the tested rice varieties, which were transformed into 155 0/1 data sites. The DNA fingerprint database of each variety was established and could distinguish it from all tested varieties. Genetic diversity analysis showed that the variation range of genetic similarity among varieties was 0.47~0.90, among which the lowest similarity coefficient was detected between Nanjing 7718 and Suxiangjing 100, while the highest similarity coefficient was detected between Nanjing 9308 and Nanjing 9036, among which there were 8 differential data sites. Genetic relationship analysis indicated that 34 varieties were divided into 6 branches, of which Nanjing 7718 is an independent branch, suggesting it has a distant relationship from other varieties. Further verification of the identification effect of core markers showed that the set of markers could effectively distinguish 14 new semi-waxy japonica rice varieties. The cluster diagram showed that they were distributed in three groups of II, III and IV, confirming the differences of genotype information among varieties; using this set of markers, the authenticity of an unknown semi-waxy rice variety was also identified. According to genotype and cluster analysis, it was determined as Nanjing 9108.【Conclusion】After optimization and screening, 54 core markers that could accurately distinguish all the tested semi-waxy japonica varieties were obtained, and developed into simple PCR markers detected by electrophoresis. Using this set of marker combinations, the DNA fingerprints of 34 semi-waxy japonica varieties in Jiangsu, Zhejiang and Shanghai were constructed.


]]> <![CDATA[Identification and Evaluation of Stripe Rust Resistance in 153 Wheat Collections]]> , caused by Puccinia striiformis f. sp. tritici (Pst), significantly reduced wheat production worldwide. Breeding resistant wheat varieties is currently considered to be one of the most economical and effective ways to control this disease. Understanding the resistance level of Chinese and International Maize and Wheat Improvement Center (CIMMYT) wheat breeding materials and the distribution of known disease resistance genes will greatly helpful for discovering the new resistance resources and improving the utilization efficiency of disease resistance genes.【Method】In the present study, we phenotyped 153 wheat breeding lines derived from China and CIMMYT at both seedling against prevalent Chinese Pst races CYR33 and CYR34. In 2018-2019, 2019-2020 and 2020-2021, using the pst races CYR33 and CYR34 to identify the materials at the adult plant stages in Ezhou, Hubei. In addition, we used the gene-based or closely linked molecular markers of known stripe rust resistance genes Yr5, Yr9, Yr10, Yr15, Yr17, Yr18, Yr26, Yr29 and YrSP to genotype the whole set of wheat collections.【Result】We found 10 lines immune against CYR33 at the seedling stage (IT: 0), including seven Chinese cultivars (Shannong 28, Luomai 163, Shimai 13, Zhongyi 6, Tanmai 98-2, Zhongmai 175, Taishan 21) and three CIMMYT lines (CIM-53, CIM-60 and CIM-71). However, only two cultivars, Tanmai 98-1 and Shannong 102, showed immune to CYR34 at the seedling stage. Based on the three years field tests, we found 64 lines showed highly resistance to stripe rust (final disease severity, FDS≤5%), including seven Chinese cultivars and 57 CIMMYT lines. The molecular marker analysis of known stripe rust resistance genes showed that there were 31, 23, 73, 2, 4, 50 and 2 lines carrying resistance genes Yr9, Yr10, Yr17, Yr18, Yr26, Yr29 and YrSP, respectively. None of any lines had Yr5 and Yr15. Based on the phenotype, only CIM-53 showed immune against two races at both seedling and adult plant stages (IT=0, FDS=0) and it might carry the known stripe rust resistance gene combination of Yr17+Yr29 based on the genotype.【Conclusion】A total of 153 wheat collections from China and CIMMYT were showed adult plant resistance to the prevalent pst races. Among these, Chinese wheat varieties mainly carry Yr9, Yr10 and Yr26, while CIMMYT wheat line mainly carry Yr17,Yr18 and Yr29, indicating that near-immunity resistance of CIMMYT wheat lines due to combinations of 1-2 moderate seedling resistance gene and 2-3 adult plant resistance genes resulting in durable resistance. Therefore, it is very urgent to expand the resistance sources and identify new resistance genes for pyramiding more genes biotechnology methods to develop new wheat varieties with durable rusts resistance and good agronomic traits. This plays an important role for controlling stripe rust in China by improving the resistance level of wheat variety overall.


]]> <![CDATA[Distribution and Variation of <i>PWL</i> Gene Family in Rice <i>Magnaporthe oryzae</i> from Heilongjiang Province and Hainan Province  #br#]]> 】Understanding the distribution and variation characteristics of PWL family in different rice blast strain populations is of great significance for studying the genetic diversity and specificity of different rice blast strain populations. 【Method】In this study, 8 pairs of specific primers were designed for the promoter region and CDS region of PWL gene family according to the avirulence (Avr) gene sequences published in NCBI. DNA was extracted from 397 Ｍonospora oryzae isolates collected from different regions of Heilongjiang and Hainan provinces in 2020, and the avirulence (Avr) gene were amplified by PCR and detected by agarose gel electrophoresis. Representative strains from different regions were selected from the detection results and the amplified fragments were sequenced. The sequencing results were compared with the base and amino acid sequences of the promoters and CDS regions of the corresponding avirulence (Avr) gene in NCBI.【Result】The results of PCR electrophoresis showed that PWL1 was not detected in all strains; specific fragments of PWL2, PWL3 and PWL4 were amplified in Heilongjiang and Hainan provinces, indicating that these three genes were distributed in the two provinces with different distribution frequencies and variation types. The distribution frequency of PWL2 was the highest in Heilongjiang Province and Hainan Province, with 98.14% and 100%, respectively. The distribution frequencies of PWL3 and PWL4 in the two provinces were significantly different, with 89.30% and 82.79% of the two genes in the Heilongjiang strain and 5.49% in the Hainan strain, respectively. Through the analysis of avirulence (Avr) gene combinations, the results showed that the combinations could be divided into five types, which were PWL2, PWL3, PWL2+PWL3, PWL2+PWL4, PWL2+PWL3+PWL4. Among them, the Heilongjiang strain contained all combination types, while the Hainan strain contained only two, indicating that the Heilongjiang strain was richer in avirulent genotypes than the Hainan strain. Sequencing of the PCR products of PWL gene family showed that the PWL gene family has abundant mutation sites in promoter region and CDS region, which can be divided into 9 types with point mutation and deletion as the main mutation types, and the mutation types of different strains from different populations are specific and consistent. Among them, PWL2 detected five types of variation PWL2- (1, 2, 3, 4, 5), and the base sequence changes lead to amino acid sequence missense mutations. Two variants were detected in PWL3 and PWL4, respectively, which were PWL3- (1, 2) and PWL4- (1, 2). Frameshift mutations occurred in both PWL3 and PWL4, which changed the following amino acids, leading to premature termination of translation.【Conclusion】The distribution and variation types of PWL gene family in different populations of blast strains showed regional differences, and the variation sites were abundant.


]]> <![CDATA[Current Situation and Strategy of Stripe Rust Resistance Genes Untilization in Winter Wheat Cultivars of Northwest Oversummering Region for <i>Puccinia striiformis</i> f. sp. <i>tritici</i> in China #br#]]> 【Objective】 Eestern and Southern Gansu is one of the epidemic centers of stripe rust and over-summering region for Puccinia striiformis f. sp. tritici (Pst) with continuous emergening of new Pst races in Northwestern China. The objective of this study is to analyze the genetic architecture of stripe rust resistance in winter wheat cultivars grown in those regions since 1990s for a better genetic diversity control of the disease, breeding of durable resistant cultivars, sustainable green and healthy ecological agriculture in Southern Gansu.【Method】The seedling and adult plant stage resistance to the prevailing Pst races CYR33, CYR34, etc. of 117 wheat cultivars (lines) were evaluated at greenhouse in 2021 and field trials in Qingshui of Gansu and Pixian of Sichuan, respectively, during 2019-2020 and 2020-2021 cropping seasons. Molecualr markers for 15 Yr genes were also applied to detect the presence of known stripe rust resistant genes. 【Result】Of the 117 varieties and lines tested, thirty-four (29.1%) were found to perform adult plant stage resistance (APR) in the field, among of these, 25.6% and 3.4% of cultivars were released in Southern Gansu, and eastern Gansu, respectively. Another 25.6% susceptible cultivars from Southern Gansu exhibited slow rusting with disease severity (DS) less than 20%. Eighty-two cultivars (70.1%) were resistant to the race CYR33 of Pst at the seedling stage. Among them, 67 (57.3%) and 15 (12.8%) were planted in Southern and eastern Gansu, respectively. However, only seven (6.0%) of the total entries were resistant to the dominant race CYR34 at the seedling stage, and all of these were cultivars from Southern Gansu, such as Lantian 131 etc. The stripe rust resistant cultivars named as Lantian, Zhongliang, and Tianxuan series at both seedling and adult plant stages were mainly released after 2010. Molecular markers screening identified the presence of Yr9 (49.6%), Yr10 (1.7%), Yr17 (12.8%), Yr18 (7.7%), Yr26 (12.8%), Yr28 (20.5%), Yr29 (10.3%), Yr30 (34.2%), Yr41 (2.6%), Yr46 (16.2%), YrZH22 (15.4%) and YrZH84 (27.4%) in some cultivars, preferly as 2-5 genes combinations in 73 (62.4%) cultivars. Pyramiding of YrZH84, YrZH22, and Yr17 with other stripe rust resistance genes could provide better disease resistance than other gene combinations. In addition, high frequency of Yr10, Yr17, Yr18, Yr28, Yr29, Yr30, Yr41, and Yr46 was detected in wheat cultiuvars grown in the dry highland Pst oversummering region. However, Yr26, Yr30, YrZH22 and YrZH84 were mainly identified in wheat cultuvars of the valley Pst overwintering region, indicating significant genetic architecture difference for the stripe rust resistance genes between the cultivars of the oversummering and overwintering regions. Higher genetic diversity of stripe rust resistance genes was found in the cultivars of the oversummering region, compared with that released in the overwintering region. 【Conclusion】Our results revealed the current status of stripe rust resistance genes and their utilization in winter wheat cultivars of Gansu, the northwest oversummering region for Pst of China, in the past 20 years. Diversification of stripe rust resistance genes have been successfully applied in the winter wheat breeding program to develop commercial wheat cultivars and lines for sustainable control of the stripe rust disease. The development of wheat cultivars with stacked stripe rust resistance genes has solved the historical problem of wheat cultivars with narrow genetic background and mono-resistance gene, domonstrating the successful control of wheat stripe rust epidemics using genetic diversity of wheat resistance gene in this region. The present study provides theoretical basis for genetic diversity control of stripe rust disease and set an example for the sustainable green ecological agriculture by breeding wheat cultivars with durable disease resistance.

]]> <![CDATA[Identification of wheat circular RNAs responsive to drought stress]]> in wheat molecular breeding. Circular RNAs (circRNAs) have been proved to play an important role in the process of plants tolerance to environmental stresses. Therefore, identifying circRNAs involved in drought stress response will help to construct a regulatory network of wheat drought tolerance, and lay a foundation for analyzing the drought resistance mechanism in wheat. 【Method】In this study, two wheat varieties (Zhoumai13 and Jimai38) with significant differences in drought resistance were used and circRNA-seq was performed on their root samples under well-watered and drought conditions. Differentially expressed circRNAs related to drought stress response were screened based on the identified circRNAs and their microRNAs (miRNAs) targets were predicted. Further, potential circRNA-miRNA-mRNA regulatory modules related to wheat drought stress response were constructed according to the expression patterns of miRNAs and their target genes under drought stress. 【Result】A total of 1409 wheat circRNAs were identified, most of which (68.91%) were exonic circRNAs. Only 133 circRNAs were simultaneously identified in both varieties. A total of 239 differentially expressed circRNAs were identified under drought stress, of which 138 circRNAs were specifically differentially expressed in the drought-resistant variety Zhoumai 13 (ZM13), and 19 circRNAs were differentially expressed simultaneously in both varieties. Besides, 34 targeted miRNAs and 1408 miRNA target genes were predicted. Based on the expression patterns of these differentially expressed circRNAs, targeted miRNAs, and miRNA target genes, five potential circRNA-miRNA-mRNA regulatory modules centered on tae-miR9664-3p, tae-miR1122b-3p, tae-miR9662a-3p, tae-miR6197-5p and tae-miR1120c-5p in response to drought stress were screened. 【Conclusion】Wheat circRNAs have obvious specificity in different cultivars and different expression patterns among different drought-tolerant wheat cultivars. A total of 239 wheat circRNAs and five potential circRNA-miRNA-mRNA regulatory modules in response to drought stress were identified in the present study.

]]> <![CDATA[Transcriptome-based Analysis of The Mechanism of Brassinolide Regulation of Anthocyanins Synthesis and Fruit Quality in Wine Grapes under High Temperature Stress]]> 】 The aims of the study were to analyze the genes involved in the regulation of grape anthocyanin accumulation and fruit quality by 24-Epibrassinolide under high-temperature stress, and to explore the molecular mechanism of EBR regulation anthocyanin accumulation in grapes under high-temperature stress. 【Method】 'Cabernet Sauvignon' grapes were treated with high-temperature stress using infrared emitter, and sprayed 0.6 mg?L-1 of EBR before the veraison. The contents of total anthocyanins, total sugar, reducing sugar and sucrose were quantified using the ultraviolet visible spectrophotometer. The mechanism of EBR-mediated accumulation of anthocyanin under high-temperature stress was analyzed by transcriptome sequencing. 【Result】 Starting from veraison , the anthocyanin content increased gradually under various treatments. At maturity, the total anthocyanin content in the high temperature group (HT) was significantly lower than that in the control group (CK), and the anthocyanin content in the high temperature and 24-Epibrassinolide group (HTE) was higher than that in the HT group and lower than CK group. Under HT treatment, the accumulation pattern of total sugar, reducing sugar and sucrose was similar to that of anthocyanins and lower than those of CK group at maturity stage. Compared with HT group, the contents of various sugars in HTE group were increased. The differences in transcriptome levels of 'Cabernet Sauvignon' fruits under the three treatments were analyzed. Through GO and KEGG enrichment, fourteen differential genes related to sucrose and starch metabolic pathways, among which 10 genes were significantly up-regulated and 4 genes were significantly down-regulated under HT and HTE treatments. The expressions of 11 genes are different in the phenylpropane metabolic pathway. Seven genes involved in anthocyanin synthesis were upregulated under the HT treatment, and 4 genes involved in lignin synthesis were significantly upregulated under the HT treatment, indicating that high temperature may promote lignin synthesis and reduce the accumulation of anthocyanins. In the endogenous hormone signaling pathway, the expression of the ABA signaling receptor genes PP2C and SnRK2 was significantly increased under high-temperature stress, and may be involved in regulating the synthesis of grape anthocyanin under high-temperature stress together with EBR. The expression patterns of some differential genes were verified by qRT-PCR, which confirmed the accuracy of transcriptome data. 【Conclusion】 EBR alleviated the inhibitory effect of high temperature stress on grapevine anthocyanin accumulation, probably due to the fact that EBR reduced the expression of lignin-related genes and changed the expression pattern of grape endogenous hormone signal transduction genes.


]]> <![CDATA[Effects of Different Color Fruit Bags on Quality of Ruixue Apple Fruits]]> Objective】The aim of this study is to explore the effect of different color of fruit bags on the fruit quality of Ruixue apple (Malus × domestica Ruixue), providing theoretical guidance and technical support for the production of high-quality Ruixue apples.【Method】The experimental materials were five-year-old trees of Ruixue using M26 as rootstock, bagged with red, orange, yellow, green, blue, indigo and purple single-layer fruit bags at 70 days after full bloom, white bags as control. And fruits were harvested at 190 days after full bloom.



The transmitted light spectrum of bags was measured by spectrometer. The indicators of fruit quality were determined, such as peel chlorophyll, ascorbic acid, soluble sugar and aroma compounds contents. To explore the effect of different light quality on fruit quality, the relationship between light and fruit quality was analyzed by correlation analysis. 【Results】The difference in the color of the fruit bags changed the composition of the light quality and had a positive correlations between light quality and fruit bags. Compared with white bag control, the transmittances of purple in purple bag were the highest, which were 1.15 times than white bag, meanwhile, the transmittances of red in red bag were the highest (1.13 times). The external quality of fruits was significantly improved after the treatment of different color fruit bags. Among the indicators, the L* and b* values of the peel were higher than white bag control, while the a* value, fruit point index and coloration index were lower. Compared with other color fruit bags, some indicators of purple fruit bags were significantly improved (P < 0.05), such as chlorophyll (0.0548 mg·g-1), total phenolic (1.325 mg·g-1), total flavonoid content of fruits (1.361 mg·g-1). Under different light quality environments, there were significant differences in fruit firmness, and the fruit firmness of the red fruit bag was significantly lower, which was 16.1% lower than white bag control. In addition, other internal quality measurements showed that the indigo fruit bags significantly improve the flavor of the fruits, which improved mainly soluble solids, sugar components and sweetness value. The detection of aroma compounds showed that the blue fruit bag significantly increases the total amount of fruit aroma compounds, which was significantly increased by 2.89 times compared with white bag control. Based on the above indicators, we conducted a correlation analysis between light quality and various quality indicators, and found that there was a close correlation between fruit external quality and light quality. The correlation coefficients between the purple/indigo, orange, and purple/blue values and the L*, a*, and b* values of the peel were 0.901, 0.810, and 0.854, respectively. The internal quality of fruit, such as chlorophyll, total flavonoid, total phenolic and total aroma compounds, were most closely related to blue light. The correlation coefficients were 0.947, 0.822, 0.851 and 0.757, respectively. 【Conclusion】According to the comprehensive analysis, purple and blue light were beneficial to improve the external and internal quality of Ruixue apple. Therefore, the transmission amount of purple and blue light can be appropriately increased in the fruit bag during Ruixue bagging cultivation to further improve fruit quality.

]]> <![CDATA[Difference in the Comprehensive Response of Dry Matter Accumulation of Rice at the Tillering Stage to Rising Atmospheric CO<sub>2</sub> Concentration and Nitrogen Nutrition and Its Physiological Mechanism #br#]]> 2 concentration and nitrogen nutrition. 【Method】In this study, a rice cultivar Liangyoupeijiu (LY) showed high response to CO2 (high-response rice cultivar) and a rice cultivar Nanjing 9108 (NJ) showed low response to CO2 (low-response rice cultivar) were selected as materials. Hydroponic experiments were carried out in the climate chamber. Two CO2 treatments and two nitrogen treatments were set up with ambient CO2 concentration (A-CO2, 400 μmol mol-1) and elevated CO2 concentration (E-CO2, 600 μmol mol-1), and high nitrogen (HN, 1.25 mM NH4NO3) and low nitrogen (LN, 0.25 mM NH4NO3), respectively. The effects of elevated CO2 concentration on root morphology and physiological activity, cytokinin (CTKs) content in leaves and roots, nitrogen assimilation enzyme activity, physiological characteristics of leaves, photosynthetic parameters, and dry matter accumulation of different rice cultivars were analyzed.【Result】(1) E-CO2 significantly increased the total crown root number, total root length (except LN level), total root surface area and average diameter of LY, improved root respiration rate and maintained high root oxidation power, but had no significant or opposite effects on NJ. (2) Regardless of nitrogen level, E-CO2 significantly increased CTKs content in LY leaves and roots, but significantly decreased zeatin nucleoside (ZR) content in NJ roots at HN level. (3) At LN level, E-CO2 significantly increased GOGAT and GDH activities in LY leaves, but significantly decreased NR activities in NJ leaves. At HN level, the activity of LY nitrogen assimilation enzyme increased under E-CO2 condition, but only NR activity increased in NJ. (4) At the LN level, E-CO2 increased the net photosynthetic rate (Pn) of LY and NJ by 28.0% and 29.4%, respectively. At the HN level, that of the two varieties increased by 41.0% and 28.1%, respectively. The significant increase in photosynthetic response of LY was attributed to the significant increase in leaf maximum carboxylation efficiency (Vc,max), maximum photosynthetic electron transport efficiency (Jmax), ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) content, chlorophyll content, and leaf nitrogen content. (5) E-CO2 significantly increased the leaf area per plant of LY under different nitrogen levels, but had no significant effect on NJ. (6) E-CO2 significantly increased the organs and total biomass of LY, and the increased level under HN was significantly higher than that under LN level. E-CO2 did not significantly affect the total biomass of NJ under different nitrogen treatments, but significantly reduced the underground biomass of NJ under HN (-16.7%). 【Conclusion】No matter at the HN or LN treatment, the response of dry matter production and physiological characteristics of LY to E-CO2 was higher than that of NJ. In the early growth stage, LY had better root morphological characters and root activity, higher CTKs content, stronger nitrogen assimilation ability, larger green leaf area and photosynthetic response capacity, which were important reasons accounting for the higher response of dry matter production under E-CO2 conditions.


]]> <![CDATA[Effect of nitrogen rate on yield formation and nitrogen use efficiency in oilseed (<em>Brassica napus</em> L.) under different cropping system]]> 【Objective】 Cropping system and nitrogen rate are important factors affecting the growth and yield formation of oilseed (Brassica napus L.). To investigate the effect of nitrogen application on yield formation and nutrient utilization of oilseed under different cropping system. 【Method】 a field experiment was carried out in Huanggang, Hubei province. A oilseed variety “Zhongyouza19” was used as the material, setting with two cropping system (rice-oil rotation, RO; soybean-oil rotation, SO) and four nitrogen rate (N0, 0; N1, 90 kg·hm-2; N2, 180 kg·hm-2; N3, 270 kg·hm-2) in this study. Yield and its components, dry matter accumulation, agronomic traits, nitrogen content and seeds quality were measured. 【Result】(1) the seed yield of SO was significantly higher than that of RO, and the pods per plant, seeds per pod and 1000-seeds weight of oilseed in different cropping system all tended to increase significantly by increasing the amount of nitrogen. Compared with N0, the seed yield of RO increased by 176.68%, 436.49% and 835.40% under N1, N2 and N3 treatments, respectively, while that of SO increased by 123.96%, 344.46% and 547.25%. And the seed yield increased by 62.09%, 31.33%, 71.79% and 12.21% under N0, N1, N2 and N3 treatments, respectively, in SO compared to RO；(2) The root crown diameter, plant height, first effective branch height and branch number of SO rape were significantly higher than those of RO at maturity stage, and the increase in each agronomic trait index were significant under different cropping system with the increase in nitrogen application; the root biomass and above-ground biomass of SO were significantly higher than those of RO at all growth stages, but the root shoot ratio was lower than that of RO. the root shoot ratio decreased significantly after seedling stage in both cropping system with increasing nitrogen application. (3) Nitrogen content and nitrogen accumulation in the root, pod shell, stalk and seeds of SO were higher than those in RO, and the increase in nitrogen content and nitrogen accumulation in each part were significant with the increase in nitrogen application; the apparent nitrogen recovery efficiency under SO were higher than those under RO, and the apparent nitrogen recovery efficiency under RO increased with the increase in nitrogen application. (4) Compared with the RO, the soluble sugar content of pod shell under SO was lower, while the amino acid content and amino acid /soluble sugar content were higher with the same nitrogen application. The soluble sugar content decreased, but the amino acid content and amino acid/soluble sugar content increased with the increase of nitrogen application. Therefore, the oil content of oilseed in SO was lower than that in RO due to the limitation of fatty acid synthesis substrate, and the oil content of seeds decreased significantly with the increase of nitrogen application in cropping system. Oil yield was maximum in both cropping system at 270 kg·hm-2 nitrogen application level, 1 678.60 kg·hm-2 and 1 665.33 kg·hm-2 for RO and 1 684.03 kg·hm-2 and 1 687.10 kg·hm-2 for SO respectively, but the difference in oil yield between 180 kg·hm-2 and 270 kg·hm-2 nitrogen application for SO was not significant. 【Conclusion】In conclusion, the nitrogen rate for RO can be controlled at about 270 kg·hm-2, but the nitrogen rate for SO can be controlled at about 180 kg·hm-2 to ensure higher nitrogen use efficiency and higher oil yield.

]]> <![CDATA[Effect of Ethylene-Chlormequat-Potassium on the Morphological Structure of Summer Maize root and yield with Different Nitrogen Application Rates]]> 】Root is an important organ for maize to obtain water and nutrients, and a developed root structure is the key to maximum maize yield potential, which is currently an important issue to be solved in maize cultivation research. Ethylene-Chlormequat-Potassium and nitrogen application can affect the development of the maize root system.  To clarify the effect of Ethylene-Chlormequat-Potassium on the construction of summer maize root morphology and yield under different nitrogen application rates can provide the theoretical and technical basis for the improvement of high yield and efficient cultivation management and rational fertilization of maize. 【Method】In 2019 and 2020, field experiments were carried out in Daliudian Village, Yanjiao Town, Langfang City and Shunyi Experimental Base, Chinese Academy of Agricultural Sciences, Shunyi District, Beijing respectively, using maize single cross Yudan 9953 as experimental material. A split-zone experimental design was used, with the Ethylene-Chlormequat-Potassium treatment (ECK) and the clear water control (CK) treatment as the main zones and the six nitrogen levels of 0 kg×hm-2 (N0), 96 kg×hm-2 (N96), 132 kg×hm-2 (N132), 168 kg×hm-2 (N168), 204 kg×hm-2 (N204) and 240 kg×hm-2 (N240) as the secondary zones, aiming to analyze the effects of ECK on root morphology and yield of summer maize at different nitrogen application rates. 【Result】The results showed that nitrogen application significantly increased root dry weight, number of aerial roots, root length, root surface area and root volume. Compared with no nitrogen application, root dry weight, the number of aerial roots, root length, root surface area and root volume increased by 18.0%, 49.5%, 20.8%, 26.2% and 34.6% on average with different nitrogen application rates, respectively. ECK treatment increased root dry weight, the number of root layers, number of roots in 1 to 2 layers and the number of aerial roots in summer maize with different nitrogen application rates by 10.4%–17.0%, 5.8%–12.6%, 10.8%–33.9% and 12.5%–79.6%, respectively, compared with CK; On the construction of root morphology, compared with CK, ECK treatment significantly increased the total root length, root surface area and root volume of summer maize with different nitrogen application rates by 7.5%–21.0%, 8.4%–29.3% and 14.3%–38.8%, respectively, and the root length with root diameter > 1.0 mm was significantly increased at medium and high nitrogen levels (N≥ N204). ECK treatment had no significant effect on summer maize yield per unit area in 2019 and 2020 with N0-N168, but significantly increased summer maize yield in 2019 and 2020 with N204 and N240, which increased by an average of 6.3% with N204 and 3.2% with N240 compared with CK. Correlation analysis showed that kernel number, 1000-kernel weight, root length, root surface area and root volume were positively correlated with summer maize yield, and the correlation coefficient between yield and root length was the highest.【Conclusion】ECK and nitrogen combined promoting maize root development and increasing summer maize yield under high nitrogen conditions. In the current study, spraying ECK at the V6 growth stage combined with 204 kg×hm-2 N fertilizer was a suitable cultivation technique and N fertilizer management practices for high-yielding summer maize in the Beijing-Tianjin area.


]]> <![CDATA[Effects of Powdery Mildew on Photosynthetic Characteristics and Quantitative Simulation of Disease Severity in Winter Wheat]]> 】 The objective of this paper was to clearly demonstrate the effects of powdery mildew on photosynthetic characteristics of winter wheat and establish a model for simulating effects of powdery mildew stress on wheat photosynthetic productivity. 【Method】 To clarify the effects of powdery mildew on wheat photosynthetic characteristics, the powdery mildew experiments of wheat were conducted under two initial inoculation degrees of wheat powdery mildew at jointing and booting stages. On this basis, a prediction model of wheat powdery mildew severity was established to quantify the physiological effects of powdery mildew on wheat. And then, based on the single leaf net photosynthetic rate (Pn) and leaf area index (LAI), the wheat powdery mildew severity prediction model was coupled with the crop growth model (WheatGrow). 【Result】 Under the stress of powdery mildew, Pn and LAI showed a decreasing trend. Compared with the control (CK), the averaged Pn and LAI decreased by 18.81% and 23.41%, respectively. Moreover, the effects of stages of powdery mildew on Pn and LAI were more serious than the initial inoculation degrees. In general, the development of wheat powdery mildew in the field had obvious gentle period, exponential outbreak period and stable period, and the temporal dynamic characteristics of wheat powdery mildew epidemic under each treatment accorded with Logistic function. Therefore, based on the Logistic fitting results, the wheat powdery mildew disease stress factor was established to reflect the stress effects of powdery mildew on wheat physiological indexes. In addition, based on the photosynthesis productivity sub-model of WheatGrow and the effect factor of wheat powdery mildew severity, algorithms to simulate the effects of powdery mildew on Pn and LAI were established, and the improved WheatGrow model was estimated by using the powdery mildew experimental datasets in independent years. 【Conclusion】 The integrated model with powdery mildew stress algorithms was better than the original WheatGrow model in predicting Pn, LAI, aboveground biomass and yield under powdery mildew stress condition, with the simulation accuracy improved by 53.29%, 43.61%, 60.09% and 67.57%, respectively. The improved model can provide the digital tool and technical support for prediction of wheat powdery mildew severity and the quantitative evaluation of wheat yield loss.


]]> <![CDATA[Analysis of Cross Compatibility Variation among Diverse Sesamum Species and Biological Characteristics of the Interspecific Hybrid Progenies]]> 】The research aims to explore the cross compatibility between different Sesamum species and analyze the biological characteristics of interspecies hybrid progeny so as to supply the foundation for efficient application of wild sesame species. 【Method】A sesame cultivar Yuzhi 11 (S. indicum, 2n=26) and 4 wild Sesamum species including S. latifolium (2n=32), S. calycinum (2n=32), S. angustifolium (2n=32), and S. radiatum (2n=64) were applied to construct interspecies cross combinations using diallel hybridization method by artificial pollination in the field. Embryo rescue method was also used to obtain interspecific hybrid F1. Interspecific hybrid compatibility was compared based on hybrid capsule formation rate. Botanical characters of hybrids were observed during flowering and mature stages. Pollen fertility was assessed using Alexander staining method. Chromosome number and karyotype characteristics of root somatic cells of hybrids were observed using smear chromosome preparation technique. Specific and polymorphic SSR primers in Sesamum were used to analyze the molecular difference in interspecific hybrids.【Result】Twenty positive and reciprocal cross combinations were constructed for the 5 Sesamum species. A total of 2019 flowers were pollinated and 370 hybrid capsules were harvested. As to the female parents with more chromosomes, hybrid capsules were more easily obtained. The cross compatibility among the 5 Sesamum species significantly varied from 1.18% (S. radiatum×S. calycinum) to 63.33% (S. calycinum×S. angustifolium). F1 plants of 9 combinations produced hybrid seeds, while the ratio of pollen sterility of F1 progeny ranged from 35.21%-100.00%. The cross S. calycinum×S. angustifolium presented the highest sterility ratio to 87.68%. Hybrid progeny exhibited the obvious heterosis over parents in plant height, plant type, and some key agronomic traits. As to the positive and reciprocal hybrid F1 derived from sesame cultivar and the wild species, leaf shape, flower shape, and flower color showed partial characters of both parents. The cross compatibility between sesame cultivar (n=13) and the 3 Sesamum species with chromosome group n=16 ranked as S. angustifolium>S. calycinum>S. latifolium. The cross compatibility between wild species S. radiatum (n=32) and the 3 species with n=16 ranked as S. calycinum>S. angustifolium>S. latifolium. Among the 5 Sesamum species, the genetic relationship between S. calycinum and S. angustifolium is relatively closest. The chromosome number of root tip cells of some hybrid plants is consistent with the theoretical value calculated from the parents. Screening results of the 3 pairs of polymorphic SSR primers indicated that 99.66% of obtained F1 plants are true hybrid. Chromosome karyotype and SSR marker screening results reflected the genetic difference and characters of Sesamum species. 【Conclusion】Among the 5 Sesamum species, the cross compatibility varies significantly and the heterosis of interspecific hybrid is obvious. Of which only S. calycinum and S. angustifolium have the relatively closest genetic relationship and could be directly applied for elite germplasm creation and interspecific hybrid breeding in Sesamum. Reproductive isolation barriers exist in other cross combinations. Some techniques including embryo rescue and molecular marker application should be used to achieve the utilization of wild Sesamum species for sesame breeding.


]]> <![CDATA[Effects on Growth Stage, Lodging Resistance and Yield Benefit of Double-cropping Early Rice in Direct Seeding Cultivation Method]]> 【Method】 For the early rice In 2020 and 2021, the conventional rice varieties Guiyu 9, Guiyu 11, Guiyefeng, Guangliangxiang 2 and hybrid rice Y Liangyou 1, which have a large area in Guangxi production, were used as test materials, in the field, Using the traditional manual transplanting as a control, the field is accurately direct seeding, For each treatment, there were three replicates. A split plot design was used in this experiment with planting method as the main plot, with rice varieties as the split plot, and set up three replications. The length of the growth period was observed, the morphology of main stem and the characteristics of the basal stem, as well as the lodging indicators such as breaking resistance, bending moment and lodging index was calculated, the yield and yield components were measured at the maturity stage, and the cost and economic benefits were calculated.【Result】(1) The growth period of direct seeding was shortened by about 2-6 days, which was mainly reflected in the period from sowing to the beginning of young spike. (2) the lodging resistance of direct seeding rice is relatively poor, and its plant height, center of gravity height and panicle dry weight are lower than that of transplanted rice; the stem thickness, wall thickness, fresh weight and dry weight of its N2 stem are also lower than that of transplanted rice, and the length of the stem is that the direct seeding rice is higher than that of transplanted rice, which may be the main reason for the weak lodging resistance of the direct rice. (3) Among the varieties tested, the actual yields of the remaining four rice varieties were lower than those of transplanted under direct-seeded cultivation, except for Yliangyou1. For varieties with relatively short growth period in the test materials, the yield under direct seeding conditions is significantly lower than that of transplanting, while for varieties with relatively long growth period，the yield difference between planting mothods is not significant, among the yield components, the increase in the number of grains per panicle and the seed setting rate are the main factors for increasing the yield of direct seeding rice. (4) From the analysis of economic benefits, among the varieties tested, Guiyu No. 11, which has a shorter growth period, has a significantly lower yield and economic benefit in direct seeding method, the economic benefits of direct seeding rice of the remaining four varieties were higher than those of transplanted rice. The main reason for this is that direct seeding rice saves labor costs in seedling and transplanting link.【Conclusion】At present, it is an urgent to develop a light and simple production model of rice with the main goal of preserving area and increasing efficiency. Compared with transplanted rice, direct seeding rice has obvious advantages such as shortening the growth period and reducing production costs. and there is a certain risk of lodging, the yield is easily affected by variety characteristics and environmental factors. Therefore, in the direct seeding cultivation of early rice, lodging-resistant varieties with medium maturity, reasonable stem length at the base, thick stems and thick stem walls can be selected. In cultivation management, the proportion of ear fertilizer should be appropriately increased to compensate for insufficient number of grains per panicle and seed setting rate can improve the yield of direct seeding rice.

]]> <![CDATA[Transcriptome Analysis of Peach Fruits at Different Developmental Stages in Peach Kurakato Wase and Early-ripening Mutant]]> Objective】 In this study, transcriptome analyses were carried out on the fruits of Kurakato Wase peach and its early-ripening mutant at different developmental stages. The key factors involved in fruit ripening regulation were explored, which provided a theoretical basis for further study on the regulation mechanism of fruit ripening. 【Method】 The flesh of Kurakato Wase peach and its early-ripening mutant was sampled at 30 d, 45 d, 59 d, 71 d and 89 d after anthesis, and transcriptome analyses were performed on the above samples. The candidate differentially expressed genes (DEGs) were verified by quantitative real-time PCR (qRT-PCR). The biological function of DEGs were analyzed through GO function and KEGG pathway. The weighted gene co-expression network analysis (WGCNA) was constructed to identify the hub modules and hub genes closely related to fruit ripening. 【Result】 Four comparison groups including y1 vs c1, y2 vs c2, y3 vs c4 and y4 vs c5 were obtained based fruit development stages. A tatal of 4 395 DEGs were identified with 2 212 up- and 2 183 down-regulated genes. There are 10, 11 and 18 candidate genes involved in ethylene, abscisic acid and auxin synthesis and signal transduction, respectively. We also constructed the interaction networks between 10 IAA proteins and their predictive interacting proteins ARF. GO function revealed that the DEGs were mainly enriched in cellular processes, metabolic processes and monomeric processes in the biological process category; in cell component category, DEGs were mainly enriched in membranes and cellular components; in molecular function category, DEGs were mainly enriched in binding protein and catalytic activity. There are more DEGs in comparison groups y3 vs c4 and y4 vs c5, and these DEGs mainly enriched in molecular functions such as binding and catalytic activity. The KEGG pathway analysis showed that a variety of secondary metabolites changed during fruit development and ripening, such as sesquiterpene and triterpenoid biosynthesis, flavonoid biosynthesis, carotenoid biosynthesis and α-linolenic acid metabolism. In addition, auxin signal transduction pathway was found to be enriched at different time nodes. 【Conclusion】 Among DEGs, a large number of hormone signal transduction pathway genes, especially auxin signal pathway genes, were enriched, and these genes may play an extremely important role during fruit ripening. The functions of candidate genes IAA and ARF and the molecular regulation of fruit ripening will be further elucidated in the future studies.


]]> <![CDATA[Effects of Low Oxygen/High Carbon Dioxide Controlled Atmosphere Combined with 1-Methylcyclopropene (1-MCP) on Quality of Yuluxiang Pear during Cold Storage #br#]]> 】The objective of this study was to clarify the effects of a controlled atmosphere (CA) with low O2/high CO2 on chlorophyll maintenance and quality of Yuluxiang pears during cold storage, to provide a theoretical basis and technical support for prolonging the storage life of Yuluxiang pears.【Methods】 Storage experiments were performed with commercial mature Yuluxiang pears treated with 1.0 μL·L-11-MCP, 1% O2, 3% CO2, and 1.0 μL·L-11-MCP combined with 1% O2 and 3% CO2 with air treatment as the control. The peel color, chlorophyll content, firmness, total soluble solids, titratable acid, ascorbic acid, and other quality indices were measured at 210 and 240 days of storage and 7 days of shelf life. Ethanol and acetaldehyde content, ethylene production, and respiratory rate of the fruits were detected by gas chromatography. The browning index of the fruit stalk and core was investigated and calculated.【Results】 Compared with ordinary cold storage, 1-MCP, CA, and CA + 1-MCP could better maintain the green color of Yuluxiang pear fruits and effectively reduce the degree of greasiness on the fruit surface. CA + 1-MCP had a more pronounced effect on the green color maintenance and greasiness control of the peel when refrigerated for 240 days and 240 + 7 days. 1-MCP and CA could inhibit the decline in fruit firmness, total soluble solids, and titratable acid. CA could inhibit browning of the core and stalk, but CA used alone reduced the content of ascorbic acid in the fruits, and CA + 1-MCP slowed the decline of ascorbic acid in CA fruits. The inhibitory effect of CA + 1-MCP on ethanol and acetaldehyde was more apparent when stored for 240 days, and the ethanol content of 20mg · L-1 was below the tolerance threshold of Yuluxiang pears. CA + 1-MCP and 1-MCP had strong inhibitory effects on ethylene production across the entire storage period. At 240 days, CA + 1-MCP and CA had a stronger inhibitory effect on the respiratory rate than did 1-MCP.【Conclusion】 Yuluxiang pears are respiratory climacteric pears, resistant to low O2 and high CO2. The freshness maintenance effect of CA + 1-MCP on Yuluxiang pears was maintained after 210 days. Therefore, when the cold storage period is less than 210 days, a single 1-MCP treatment of 1.0 μ L · L-1 could be used. When the cold storage period is greater than 210 days, fruits should be first treated with 1.0 μL·L-1 1-MCP, and then stored under CA with low O2/high CO2 of 1% O2 and 3% CO2, which can maintain the appearance and internal quality of fruits, as well as significantly prolong the cold storage life.


]]> <![CDATA[Effects of Seed Soaking with Chitooligosaccharide on the Growth of Sprout and Endogenous Phytohormone Content in Potato Minitubers]]> 】 Seed soaking treatment is commonly used in potato production to promote tuber germination and bud growth. However, improper use of seed soaking agents can trigger an imbalance of endogenous plant hormone levels, leading to the emergence of potato high-legged seedlings. To provide a theoretical basis for the safe use of chitooligosaccharide as a seed dressing agent for potato minituber, its immersion effects on the growth and endogenous hormone content of potato minitubers were studied. 【Method】The minitubers of 'Favorita' were soaked with chitooligosaccharide solution at different concentrations of 10, 50 and 200 mg?L-1 (w/v) respectively, and the most effective concentration for promoting bud growth was screened. Seeds treated with 50 mg?L-1 (w/v) chitooligosaccharide for 15 min was the treatment group (COS50), and the negative and positive control groups were treated with distilled water (Con) and 15 mg?L-1 gibberellin 3 (GA3), respectively. The germination rate, germination energy, bud length and bud diameter of tubers after seed soaking treatment were determined. The content of endogenous hormones in bud tissue was analyzed by ELISA before treatment (BT), before germination stage (BGS), germination stage (GS), and vigorous growth period (VG) respectively, and the morphology of terminal bud cells of GS was observed by paraffin section staining. Pearson correlation analysis was used to determine the intrinsic differences between shoot growth and endogenous hormone content. 【Result】Seed soaking with 50 mg?L-1 (w/v) chitooligosaccharide effectively promoted the germination and growth of tuber buds of the potato minitubers. The bud length and bud diameter of the treated samples were significantly higher than the Con group (74.7%) and GA3 group (37.2%). On the 5th day after soaking, the tuber germination rate reached 100%, which was 40% and 17% higher than the negative and the positive control respectively. The germination energy of the minitubers was significantly enhanced. On the 5th day after treatment, the germination energy of minituber increased by 80% and 28.6% compared with Con and GA3 groups, respectively. Different seed soaking treatments also showed significant differences in the endogenous hormone contents in the terminal bud meristem of minitubers. Compared with the negative control, COS50 treatment elevated the levels of auxin, cytokinin, and gibberellin in the tubers during VG period, and the contents of these hormone increased by 11.4%, 2.7%, and 2.5%, respectively, while the content of abscisic acid decreased by 3.2% (P<0.05). The positive control treatment promoted the highest levels of endogenous gibberellin, cytokinin and auxin, and COS50 treatment group had significantly lower levels of auxin, cytokinin and gibberellin than the positive control group by 5.1%, 8.4%, and 2.0% respectively (P<0.05). No significant reduction was observed in the level of abscisic acid. However, the contents of endogenous polyamines in the apical bud meristems of the minitubers treated with COS50 was 7.0% and 2.8% higher than those in the Con and GA3 treatment groups, respectively. The results of paraffin section staining revealed that the morphological differences between the minitubers terminal bud cells was attributed to the different seed soaking treatments. The cells of the terminal bud meristem expanded resulting in elongated and flat shape in GA3 treatment, while the cells of COS50 treatment group showed a uniform shape, similar to the negative control. Furthermore, the sprouts growth, sprouts diameter, germination rate and energy of minitubers were positively correlated with the increase of cytokinin, gibberellin and polyamines contents induced by COS50 treatment (P<0.05), while abscisic acid and ployamines content were significantly negatively correlated (r=-0.785, P<0.01). 【Conclusion】Seed soaking with chitooligosaccharide increased the contents of auxin, cytokinin, gibberellin, and polyamines in sprouts of minitubers. The treatment also increased the germination rate, sprouts length and sprouts diameter of potato minitubers.. Uniform enlargement of meristematic cells in the sprouts of minitubers observation showed that COS50 treatment did not affect the longitudinal elongation of apical bud meristematic cells during the expansion process, causing the bud to grow wildly. However, gibberellin content decreased significantly in seed soaked with 50 mg?L-1 (w/v) chitooligosaccharide compared with the treatment with exogenous gibberellin 3.


]]> <![CDATA[Genetic Analysis of Fruits Characters in Reciprocal Cross Progenies of Chinese Cherry [<i>Cerasus pseudocerasus </i>(Lindl.) G.Don] #br#]]> 】To pave the way for the construction of high-density genetic map and QTL (quantitative trait locus) analysis, and to facilitate the parental selection and mating design in the breeding programs targeting for new varieties in Chinese cherry.【Method】We investigated the heredity variation and inheritance tendency of 17 fruit quality traits in the F1 segregating populations (n=226) derived from the reciprocal cross between Nanzaohong (NZH, early maturity, orange red) and 'Hongfei' (HF, purple red, with good comprehensive characteristics). Traits included were fruit weight, longitudinal, transverse and lateral diameter, total soluble solids (TSS), soluble sugar (SS), titratable acid (TA), anthocyanin content, fruit shape index, fruit development period, and fruit stalk length, etc. 【Result】The average fruit weight in offspring of both NZH × HF (4.30 g) and HF × NZH (4.05 g) was smaller than the mid-parent value. The TSS content (14.55% and 14.51%) of the hybrid was generally higher than that in the high parent (HH) (12.97%), with a heterosis (H) value of 19.61% and 19.28% in the two populations respectively. The average TA content of individuals from the reciprocal cross was lower than the low parent (LL) (47.92% and 41.94%). Peel color segregated in the F1 progenies, with orange-red, red, purple-red and black purple being observed. Hybrids with red fruit color accounted for the largest proportion, reaching 53.38% and 61.54% of all offspring in the two populations. The average fruit development period of NZH × HF progenies was two days shorter than that of HF × NZH progenies, which was mainly affected by the male parent. The fruit stalk length showed heterosis with HH values of 49.25% and 43.33%. Mix inheritance models were evaluated. The results showed that the two major genes plus polygenes model was the most suitable one for 11 (out of 12) quantitative traits except for the fruit longitudinal diameter, which fits the one major gene plus polygenes model best.【Conclusion】The main fruit quality characteristics were quantitative traits controlled by polygenic loci. The inheritance trend of the fruit weight, longitudinal, transverse, lateral diameter, TA, and anthocyanin content tended to be decreased, while the TSS, SS content and, fruit stalk length tended to be increased.


]]> <![CDATA[Genome-Wide Identification and Expression Analysis of XTH Gene Family in Peach Fruit During Storage]]> 】The aim of this study was to identify XTH genes family from peach, and to analyze the expression of PpXTHs in different texture peach fruit during storage, which not only provided data support for exploring the candidate PpXTHs involved in peach fruit softening, but also laid the foundation for further studying PpXTHs function in peach fruit softening.【Method】The HMM profiles of the Glyco_hydro_16 domain and XET_C domain were used to search all XTH proteins with the Hmmer 3.1 software in peach protein database. Then the molecular weight, theoretical isoelectric point and other physicochemical properties were predicted by online tool ProtParam. PpXTHs subcellular localization were predicted by online software Plant-mPLoc. The MEGA 11 software was used to construct phylogenetic tree. The online tool MEME was used to analyze conserved motif, and conserved protein domain and gene structure map were draw by Tbtools. According to the PpXTHs family gene location information, chromosome mapping was carried out in MapChart software. Then the expression of PpXTHs in different texture of peach fruit during storage were detected by qRT-PCR. 【Result】A total of 27 PpXTH genes were systematically identified from peach, which were distributed on 7 chromosomes. Based on the phylogenetic tree, ancestral group, Ⅰ/Ⅱ subfamily, ⅢA subfamily and ⅢB subfamily were classified. In addition, according to the analysis of protein domains, all PpXTHs gene family proteins had Glyco_hydro_16 and XET_C conserved domain. The results of qRT-PCR showed that PpXTH33 belonging to ⅢB subfamily was up-regulated with the extension of storage period in melting peach, and the expression was prominent higher than that in stony hard peach storage period. The positive clone sequencing was consistent with the CDS sequence of Prunus persica reference genome with the length of 924 bp coding 307 amino acid sequence. The PpXTH33 combined with GFP may mainly located in the cell wall and nucleus by confocal laser scanning microscopy. 【Conclusion】All 27 PpXTHs protein structures contained 2 highly XTH conserved domains and distributed on 7 chromosomes . The expression characteristics of PpXTH33 in different textures of peach fruit during storage suggested that PpXTH33 was closely related to peach fruit softening during storage.

]]> <![CDATA[Analysis of <i>VlCKX4</i> Expression Characteristics and Prediction of Transcriptional Regulation in Grape (<i>Vitis vinifera</i>) ]]> Objective】The cytokinin dehydrogenase/oxidase VlCKX4 and its promoter were cloned to analyze the expression characteristics, promoter activity and transcription factor prediction, providing a basis for the molecular mechanism that VlCKX4 involved in cytokinin-mediated berry-setting in grapes. 【Methods】The gene sequence of cytokinin oxidase/dehydrogenase 4 (VlCKX4) in 'Kyoho' grape (Vitis vinifera × Vitis labrusca) was studied by bioinformatics method. The gene and its promoter were cloned by PCR, and the expression characteristics of VlCKX4 were analyzed by real-time quantitative PCR (qRT-PCR). GUS activity assay was used to analyze the promoter activity. The transcriptional regulatory relationship of VlCKX4 was predicted by PlantTFDB, CisBP databases, and co-expression relationship was analyzed by package “GINE3” in R and the output results were visualized by Gephi software. 【Results】The total length of VlCKX4 is 1582 bp, which contains 1566 bp open reading frame (ORF), encodes 522 amino acids, and has the family characteristic FAD domain and cytokinin binding (CK-binding) domain. qRT-PCR results showed that VlCKX4 was highly expressed in inflorescence and leaf, expression of tendril is lowest. The expression of VlCKX4 decreased first and then increased after treatment with cytokinin (CPPU), while the expression of VlCKX4 increased first and then decreased after treatment with the cytokinin inhibitor lovastatin (Lov). Cis-element analysis showed that the VlCKX4 promoter contained response elements of methyl jasmonate (MeJA) and other hormones. GUS histochemical staining showed that VlCKX4 responded to the treatment of these hormones. Predictive analysis of transcriptional regulation showed that MYB, DOF and WRKY transcription factors were involved in transcriptional regulation of VlCKX4. Combined with transcriptomic expression data and coexpression relation, WRKY20, DOF1.5 and MYB59 were identified as key candidate transcription factors. 【Conclusion】VlCKX4 is induced by CPPU and participates in the process of promoting grape berry setting, during which prediction is regulated by transcription factors such as WRKY20、 DOF1.5 and MYB59.


]]> <![CDATA[Research Progress on the Application of non-Saccharomyces during Wine Fermentation]]> Saccharomyces yeast are naturally present on grape skin, and mainly play their roles in the maceration and initial stage of fermentation during winemaking process. More and more concerns have been recently focused on the application of non-Saccharomyces yeast in wine fermentation. Non-Saccharomyces yeast often have weaker fermentation ability than Saccharomyces cerevisiae and can convert the reducing sugar into ethanol and other fermentation by-products. Therefore, non-Saccharomyces are the potential excellent yeast for producing wine with complex flavor traits and lower ethanol degree. Different non-Saccharomyces yeast species have different metabolic characteristics in wine fermentation applications. The selection of non-Saccharomyces yeasts with certain characteristics for application in fermentation can improve the specialized quality of wine. This review based on the initial summary on the species, winemaking traits, and application ways of commercial non-Saccharomyces yeast, and emphasized on the positive role of non-Saccharomyces in wine color, aroma, taste, safety and health, their metabolic mechanisms and corresponding research hotspot. The positive role of non-Saccharomyces in wine color includes the promotion of high acid production, high polysaccharide production, high extracellular pyruvate production and low sorption properties. Different non-Saccharomyces yeast can promote the fruity aroma enhancement in wine by low production of ethanol, acetaldehyde, and volatile phenols, and high production of ethyl acetate, acetic acid ester, ethyl ester, higher alcohols, enzymes related with the release of terpene and mercaptan, and therefore improve the aroma complexity of wine. Non-Saccharomyces yeast can regulate wine mouthfeel traits by high production of glycerol, polysaccharide, and lactic acid, and degradation of malic acid. In addition, non-Saccharomyces yeast can improve the safety quality of wine by decreasing the SO2 dosage as biological control agent, reducing the content of toxic compounds through metabolic degradation during alcoholic fermentation. This review further analyzed the current research status on genome and microsatellite loci analysis. The main inoculation strategies were discussed on application of non-Saccharomyces yeast during wine fermentation, and six aspects were posed for further research concern. It will provide theoretical references for the research on application of the non-Saccharomyces yeasts in wine alcoholic fermentation.


]]> <![CDATA[Identification of the root-specific soybean <i>GmPR1-9</i> promoter and application in <i>Phytophthora</i> root-rot resistance #br#]]> Objective】The objective of this study is to identify the root-specific promotors and the core regulatory sequence of soybean. Then evaluate the potential application of the synthetic promoter in Phytophthora root-rot resistance. 【Method】The genes which specifically expressed in roots with high expression levels were screened based on the transcriptome date of soybean root, stem and leaf tissues in the seedling stage. Based on the distribution of the cis elements, the promoter truncation approach was used to map the minimal promoter controlling root specific expression in soybean hairy roots. The obtained minimal promoter fragment was concatenated with the Phytophthora inducible promoter elements p4XD to construct the synthetic promoter. The synthetic promoter driven over-expression of Phytophthora resistance related gene GmNDR1 in soybean hairy roots, then the resistance level of transgenic tissue to Phytophthora and the expression profiles of GmNDR1 during the interaction had been analyzed. Furthermore, the transgenic Nicotiana benthamiana plants were generated to evaluate the resistance at plant level. 【Result】Though screening, six soybean PR1 homologues with significant root specific expression manner were identified, and GmPR1-9 had the highest promoter activity. Numbers of root specific expression related cis elements were identified in promoter sequence using the online tool PLACE. Truncation analysis of the promoter showed that serial 5' end deletions L1, L2, L3, L4 and L5 had different GUS activities. The L5 (-166 to -1) fragment had 80% activity of the full-length promoter, and was able to drive GUS expression in roots of transgenic N. benthamiana. GUS enzyme activity was almost undetectable in three 3’ end deletions R1, R2 and R3, and the double terminal deletion mutant M1. When the fusion promoter p4XD-L5 driven GmNDR1 expression in soybean hairy roots, the resistance to P. sojae was significantly enhanced. The disease severity and lesion length were significantly reduced in the over-expression hairy roots when compared with control, and the relative biomass of Phytophthora decreased by 66.5% at 48 h post inoculation. GmNDR1 maintained high expression level in over-expression tissues, with 39.2 times of that in control tissues. The expressions were further up-regulated after inoculation, and reached the highest level at 36 h. In p4XD-L5::NDR1 transgenic N. benthamiana plants, the expression of GmNDR1 was significantly higher in roots than that in stems and leaves. Fifteen days after P. capsica inoculation, the plant height, root length and fresh weight of GmNDR1 over-expression plants were significantly higher, and meanwhile the leaf wilting rate and lesion length were significantly lower. 【Conclusion】This study obtained a soybean root specific promoter and identified the core regulation sequence. The strategy which driven the expression of GmNDR1 by the synthetic promoter p4XD-L5 combined the inducible and tissue-specific promoter core elements can significantly enhance the resistance of transgenic soybean hairy roots and Nicotiana benthamiana plants to Phytophthora pathogens.


]]> <![CDATA[Deciphering of the Genetic Diversity After Field Late Blight Resistance Evaluation of Potato Breeds]]> 】To evaluate the late blight resistance in field. To use SNP markers to analyze the genetic diversity of late blight resistance of potato germplasm and discern the genetic segments that may affect the phenotype of potato late blight resistance, and to provide a theoretical basis for the innovation and utilization of potato late blight resistant germplasm.【Method】Field resistance to late blight was evaluated in potato germplasm at multiple locations and over the course of several years. SNP markers were detected using a dd-RAD simplified genome sequencing strategy. The population genetic structure was analyzed using Admixture, principal component analysis was conducted using GCTA, a phylogenetic tree was constructed using fastTree, population genetic diversity parameters were calculated using the populations command in the Stacks package, selective sweep parameters were calculated using vcftools, protein sequences were aligned using Clustal Omega, and a proteins phylogenetic tree was drawn using MEGA6. Genome-wide association analysis was constructed using GEMMA 0.98.1 and QQ and manhattan plots were drawn using CMplot.【Result】Through years of evaluation of late blight field resistance in multiple locations, potato germplasm of 101 late blight resistant varieties (lines) and 21 susceptible varieties were obtained. A total of 8 697 602 relatively evenly distributed SNPs were obtained using dd-RAD simplified genome sequencing on these germplasms. This germplasm can be further divided into 6 populations through structural analysis, principal component analysis and phylogenetic analysis. The average nucleotide diversity (π) within the 6 populations ranged from 0.2055 to 0.2572 and the fixation index (Fst) among the six populations ranged from 0.156909 to 0.187336, revealing a relatively large genetic diversity for these germplasms. The expected heterozygosity (He) within the 6 populations ranged from 0.187 to 0.2297 and the observed heterozygosity (Ho) ranged from 0.0829 to 0.1186. The values of Ho were less than those of He in all six populations. Meanwhile, the inbreeding coefficient (Fis) for the six populations ranged from 0.2412 to 0.3554, indicating inbreeding events during the breeding process. To identify the genetic segments that may affect the phenotype of potato late blight resistance, π ratios and Fst among different late blight resistance germplasms in the whole potato genome were calculated using 20 kb as the window length and 5 kb as the step length. The 745 genetic segments which had a π ratio value in the lowest 5% and a Fst value in highest 10% were further analyzed by performing a selective sweep analysis. These selected segments contain a total of 507 genes, including 4 NBS-LRR genes. A genome-wide association analysis was also conducted, yielding 9 SNP highly associated with late blight resistance. Of the 69 genes located in the genome within 50 kb around the 9 SNPs, 15 genes were predicted to be involved in stress response, and 12 genes were predicted to be involved in removing peroxide radicals.【Conclusion】Large amount of SNPs, which are relatively evenly distributed in the potato genome, can be genotyped by dd-RAD simplified genome sequencing. Potato late blight field resistance germplasm has a large genetic diversity, but had inbreeding events in the process of breeding. Population structure analysis can reveal the genetic relationship between potato germplasms, which can further provide a theoretical basis for parental selection in breeding. Selective sweep and genome-wide association analyses help to isolate genetic segments that may affect late blight resistance traits.]]> <![CDATA[Mutation Analysis of Insecticide Target Genes in Populations of<em> Spodoptera frugiperda</em> in China]]> Background】The fall armyworm (Spodoptera frugiperda) is an most damaging agricultural pest in the tropical and subtropical areas of America, it has rapidly expanded to more than 100 countries around the world since 2016, and has now invaded 27 provinces in China, posing a great threat to food security. Resistance may become an increasingly serious problem in many regions with the heavy reliance on insecticides for several years and lead to low control efficiency. FAW had spread to the north of the Great Wall rapidly. However, there are few studies on insecticide resistance and annual variation in China, especially the Protection zone of the Great Wall.【Objective】The objective of this study is to clarify susceptibility and differences of S. frugiperda populations to insecticides in the Great Wall protection zone and other area of China, and provide evidence for rational use of insecticide.【Method】Samples of FAW were collected from maize fields in 13 provinces (Autonomous Region, Municipality)  in China，and the genomic DNA was extracted. The mutations of resistance targets to carbamate, pyretoid and bisamide insecticides in 362 individuals collected from 47 cities (districts) of 13 provinces (Autonomous Region, Municipality) in 2020 and 2021 were analyzed with sequencing of the PCR products individually. 【Result】There were 6 genotypes of mutations with frequency of 40.6% in ace-1 to carbamate insecticides in all the samples. The frequency of A201S heterozygous and homozygous mutations were 8.4% and 14.9%, respectively, and the frequency of F290V heterozygous mutations was 25.7%, which was higher in the key prevention region than that in the migratory transition region and annual breeding region, while the frequency of A201S mutation was lower than that in both regions. The average frequency of ace-1 mutation was higher in the Great Wall protection zone, and that in Huang-Huai-Hai interception zone, Yangtze River Basin and southwest and South China protection zone were similar and low. There was no significant difference in the frequency of ace-1 mutation between the populations in 2021 and 2020. No mutations were detected in pyrethroid vgsc and bisamide ryr.【Conclusion】A201S and F290V mutations with high frequency in ace-1 is one of the mechanisms conferring carbamate resistance in many populations in China. The use of Carbamates should be restricted in the control of S. frugiperda. No mutations had been detected in the vgsc and ryr, suggesting susceptibility to pyrethroids and diamides for rational rotation, however, the low frequency of mutation in S. frugiperda and common mutation in Spodoptera exigua (relatives of S. frugiperda) to pyrethroids and diamides have been detected, so we should evaluate the resistance of median lethal concentration and target mutation with high selection stress in the lab and field populations fed by different host and establish rapid diagnostics methods of insecticide resistance for the sustainable control of S. frugiperda.

]]> <![CDATA[Formation and Function of Paraspeckle During Pre-implantation Embryos Development in Yak (<em>Bos grunniens</em>)]]> 】The aim of present study was to identify of paraspeckle formation stages during early embryonic development in yak (Bos grunniens). Furthermore, we also determined long non-coding RNAs (LncRNAs) involved in paraspeckle formation and study effects and regulatory mechanism of their formation on the subsequent developmental ability of yak embryos.【Method】The yak embryos were produced by in vitro fertilization (IVF), DAPI staining of embryonic nuclei combined with paraspeckle protein 1 (PSPC1) mRNA detection were done by quantitative real-time fluorescence PCR (qRT-PCR) at different stages in order to confirm paraspeckle formation. PSPC1 protein in embryos was verified by immunofluorescence technique. The levels of encoding nuclear paraspeckle assembly transcript 1(NEAT1), coactivator associated arginine methyl transferase 1(CARM1) and non-POU domain containing octamer-binding protein(p54nrb) mRNAs were also detected by qRT-PCR at different stages. The mRNA level of PSPC1 in zygote was inhibited by RNA interference technology, and the developmental rate of embryos in subsequent stages was compared. The blastocyst quality was evaluated by analyzing the number of total cells, trophoblast cells(TE) and inner cell mass (ICM). B-cell lymphoma/leukemia-2(Bcl-2) and b-cell lymphoma/leukemia associated X protein (Bax) in blastocysts form in the control and PSPC1 mRNA interference groups was detected.【Result】(1) Paraspeckle could be observed in the nuclei of embryos at all different stages; however, nuclei can be more clearly seen at 2-cell stage and 4-cell stage. The PSPC1 mRNA was higher in yak embryos from 2-cell to morula stage, which were highest in embryos at 4-cell embryos and morula. The fluorescence intensity of PSPC1 protein was strongest in embryos from those stages. (2) Levels of NEAT1, CARM1 and p54nrb mRNA were higher from 2-cell to morula stage than in other stages. NEAT1 and p54nrb were found to be highest in embryos at 4-cell stage, while CARM1 was not significantly different from 2-cell to morula stage (p > 0.05). (3) The developmental rates of morula and blastocyst in PSPC1 mRNA interference group were reduced, which was more significantly reduced in morula rate. Total number of blastocyst cells in PSPC1 mRNA interference group was significantly lower than that in the control group, which was mainly caused by ICM reduction. There was no significant difference in number of TE between the two groups. (4) The levels of Bax mRNA and protein were enhanced in blastocyst form PSPC1 mRNA interference group, while the levels of Bcl-2 mRNA and protein were reduced in blastocyst; and the cell lysis was observed in ICM.【Conclusion】Results in our present study show that paraspeckle formed at 2-cell to morula stage transition in the yak embryo, and was more prominent in 4-cell stage. The expression of PSPC1, NEAT1, CRAM1 and p54nrb in the stages of paraspeckle formation were on high levels. Interference with PSPC1 mRNA in yak zygotes resulted in decreased developmental ability of subsequent embryo. The blastocyst quality was also reduced by inducing apoptosis of inner cell mass, which was also involved in the regulation of cell fate determination in early embryo development.


]]> <![CDATA[Effects of Rhizosphere Oxygen Environment on Phosphorus Uptake of Rice Seedlings and Its Physiological Mechanisms in Hydroponic Condition]]> -1, high oxygen: DOC>6.0 mg·L-1, continuous bubbling with atmospheric air, and normal conditions as CK) controlled by on-line dissolved oxygen meter. After different oxygen treatments, the rice seedling growth (biomass, root morphological structure), root physiology (root activity, phosphorus absorption kinetics, phosphatase activity, root secretion of organic acids, citric acid, etc.), and phosphorus absorption and accumulation were measured and analyzed.【Result】 (1) The medium oxygen treatment significantly promoted the occurrence and growth of tillers, and increased the biomass, root shoot ratio, phosphorus content and accumulation of the two tested varieties; the high oxygen treatment reduced the plant height and shoot biomass, but had no significant effect on root biomass. (2) Compared with the control, the total root length, surface area and total volume of root were significantly increased, and the average root diameter were significantly decreased after the medium oxygen treatment, while the high oxygen treatment was opposite to the medium. The medium and high oxygen treatment could promote the secretion of organic acids (the total amount of organic acids, oxalic acid, tartaric acid, and citric acid content increased), and increase the activity of acid phosphatase in leaves and roots. However, compared with high oxygen, the medium oxygen treatment significantly enhanced the activity of roots, optimized the kinetic parameters of phosphorus absorption, increased Imax, and decreased Km and Cmin. (3) The results of correlation analysis showed that the phosphorus accumulation and aboveground phosphorus content were significantly positively correlated with root morphology (total root length, root surface area, average diameter and total volume of root), root activity, absorption kinetic parameters Imax, the content of oxalic acid and tartaric acid, and negatively correlated with phosphorus absorption kinetic parameters Km and Cmin. The root phosphorus content of root was significantly positively correlated with root acid phosphatase, root activity, total organic acid and oxalic acid content, but not significantly with other indexes.【Conclusion】The moderate increase of dissolved oxygen concentration (medium oxygen treatment) could improve the activity of acid phosphatase in leaves and roots, root activity, the root secretion content of oxalic acid, tartaric acid and citric acid, optimize the root morphological structure (increase the root surface area) and phosphorus uptake kinetics of rice seedlings so as to increase phosphorus content and accumulation of rice. Therefore, the selecting appropriate cultivation measures could change the rhizosphere oxygen environment and improve the ability of phosphorus absorption of rice in field planting.]]> <![CDATA[Effects of High Temperature Stress in Different Periods on Dry Matter Production and Grain Yield of Summer Maize]]> 】With the global warming, summer high temperature weather occurs more frequently and more intensely, and the duration of high temperature is more longer, which is the main abiotic stress limiting the improvement of summer maize yield in Huang-Huai-Hai region. In this study, the effects of high temperature stress on dry matter production performance and grain yield of summer maize were investigated by analyzing the differences of photosynthetic characteristics, carbon assimilate accumulation and distribution and grain yield of two different heat sensitive summer maize varieties under high temperature stress at V12 stage and VT stage, respectively. 【Method】In this study, heat resistant maize variety Zhengdan 958 (ZD958) and heat sensitive maize variety Xianyu 335 (XY335) were used as materials. The high temperature stress treatments (day 38℃12 h/night 28℃12 h) were set at V12 and VT stage, respectively, at the same time, thenormal temperature treatment (day 32℃12 h /night 22℃12 h) was set as the control. High temperature greenhouse equipped with automatic temperature and humidity control facilities was used to simulate the effect of natural field high temperature. The dynamic characteristics of leaf area index (LAI), carbon metabolism enzyme activities, photosynthetic rate and carbon assimilate accumulation and allocation were compared after high temperature stress, aimed to determine the response mechanism of dry matter production performance and grain yield to high temperature stress. 【Result】After high temperature stress, LAI, carbon metabolism enzyme activities, net photosynthetic rate and dry matter accumulation of two cultivars were significantly decreased. LAI, RuBP carboxylase activity, PEP carboxylase activity, net photosynthetic rate and dry matter accumulation of ZD958 and XY335 decreased by 2.98%-4.21%, 40.38%-54.46%, 16.88%-30.60%, 18.14%-25.49%, 12.83%-19.38% and 3.80%-5.07%, 56.56%-76.16%, 26.33%-33.66%, 22.37%-34.62%, 22.07%-26.72%, respectively. The decrease range of high temperature stress in VT stage was larger than that in V12 stage. After high temperature stress, transpiration rate of summer maize leaves increased, while leaf water use efficiency decreased significantly. Under high temperature stress, 13C assimilation of ZD958 and XY335 decreased by 18.48% and 22.82%, respectively, and the proportion of 13C assimilation in grains decreased. The high temperature stress significantly decreased grain number per spike and grain yield, although 1000 grain weight increased slightly. After V12 high temperature stress, 1 000 grain weight of ZD958 and XY335 increased by 2.36% and 3.17%,respectively, while thegrain number per spike and yield decreased by 62.53% and 70.50%, 45.87% and 62.87%%, respectively. After VT high temperature stress, grain number per spike and yield decreased by 70.53% and 85.41%, 66.89% and 80.61%%, respectively. The decrease range of high temperature stress in VT stage was larger than that in V12 stage, andXY335 decreased more than ZD958. 【Conclusion】The high temperature stress reduced LAI, RuBP carboxylase and PEP carboxylase activities, and significantly reduced photosynthetic rate and dry matter production performance of summer maize. Under high temperature stress, thegrain number per spike decreased significantly, which inhibited the transportation of carbohydrate from leaf and stem to grain, resulting in lower grain yield. The effects of high temperature stress on dry matter performance and grain yield of summer maize in VT stage was significantly greater than that in V12 stage. The decrease of heat sensitive variety XY335 was significantly greater than that of heat resistant variety ZD958 in two periods. 


]]> <![CDATA[Study on the Quality Parameters of Strong Gluten Wheat and Analysis of Its Relationship with Meteorological Factors in Shandong Province]]> 【Objective】In this paper, the dominant distribution areas of strong gluten wheat were clarified in Shandong province, and the influence of key meteorological factors on its quality parameters was analyzed. 【Method】The high-quality strong-gluten wheat Jimai 44 was selected as the research material, and 296 samples were collected from 44 counties and districts in Shandong provincein the growing seasons of 2018 to 2020. The relationship of meteorological factors, such as light, temperature and water, in different growth periods with wheat quality parameters was analyzed byusing the method of stepwise regression. The geographic information system (GIS) was used for spatial visualization analysis, and the possible distribution of high-quality strong-gluten wheat advantageous areas was explored in Shandong province. 【Result】There were differences in the performance of each quality parameter in the different regions in different years. The proportion of samples reaching the standard of strong gluten wasshown as maximum pull resistance> water absorption rate>bulk density>stabilize time>protein content>tensile area>wet gluten content in two years, and the coefficients of variation of quality parameters from large to small were stabilize time, tensile area, maximum pull resistance, wet gluten content, protein content, water absorption rate, and bulk density. The bulk density in western and northwestern Shandong was generally higher than that in other regions, and decreased with the increase of longitude, which was mainly related to the influence of rainfall during the rejuvenation-jointing period. The protein content was positively affected by the accumulated temperature ≥5℃ during the anthesis-milk maturity period, while increased from southwest to northeast in 2018-2019 and from northwest to southeast in 2019-2020. The wet gluten content was higher in the eastern Shandong region, which was significantly related to the high rainfall during the anthesis-milk maturity period in this region. The stabilize time was significantly negatively correlated with the maximum temperature during the jointing-anthesis period, and positively correlated with the rainfall during the sowing-overwintering period, and this affected it’s high value distribution and regional variation; the tensile area was significantly negatively correlated with the accumulated temperature ≥5℃ during the rejuvenation-jointing period, and gradually decreased from the west to the east of Shandong province. The maximum pull resistance was significantly negatively correlated with the accumulated temperature ≥5℃ during the anthesis-milk maturity period; it was low in the east-west direction and high in the middle area of Shandong province. Taking into account comprehensively, the high-quality probability of high-gluten wheat planting in eastern and southern Shandong province was stronger than that in central and northern, and the lowest in western. 【Conclusion】Eastern and southern regions were the optimal planting areas for strong-gluten wheat in Shandong province, with the greatest possibility of high quality. The high maximum temperature during rejuvenation-jointing period, jointing-anthesis period and grain-filling period was unfavorable to the rheological parameters of wheat dough, while the increase of effective accumulated temperature during anthesis-milk maturity period was beneficial to the increase of protein content. The rainfall during sowing-overwintering period was beneficial to the increase of dough stabilize time; when the rainfall was less than 14.5 mm during anthesis-milk maturity period, it was not beneficial for the wet gluten content to reach the strong gluten standard; the rainfall during the rejuvenation-jointing period is was not conducive to the increase of bulk density. Therefore, in the production of strong gluten wheat, it was suggested that irrigation should be carried out in the overwintering period and early grouting according to the weather conditions, and the irrigation time during rejuvenation-jointing period should be postponed as far as possible.

]]> <![CDATA[Effect of Post-anthesis Shading Stress on Eating Quality of Indica Rice in Chengdu Plain]]> The aim ofthis study was to clarify the effect of post-anthesis shading stress on the eating quality of indica rice in Chengdu Plain, so as toprovide the theoretical and practical basis for the selecting of shade-tolerant rice varieties in low light rice region. 【Method】Field light control experiments were conducted in 2019 and 2020 in Wenjiang, Sichuan by using indica rice varieties with different amylose contents as materials. The effects of shading stress on eating quality of rice was studied by measuring the components and RVA spectrum values of rice, as well as the texture properties and eating quality of cooked rice. 【Result】(1)Shading stress significantly decreased amylose, amylopectin, and total starch contents of rice, but significantly increased the contents of protein and fat. (2)Shading stress significantly decreased the peak viscosity and breakdown of rice, while increased the pasting temperature and setback. (3)Shading stress also significantly increased the hardness of cooked rice, but decreased the stickiness and elasticity, which contributed to a significant reduction in the comprehensive score of cooked rice by decreasing both appearance and taste. (4)The results of principal component analysis showed that therice components, RVA spectrum values, and texture properties could explain 81.2% of the total variation of eating quality of cooked rice. The comprehensive score of rice was significantly and positively correlated with the amylose, starch content, peak viscosity, breakdown, elasticity and stickiness, but negatively related to the protein and fat contents. 【Conclusion】The Pprotein and fat contents possessed greater influence on the eating quality of cooked rice than that of amylose and starch contents under shading stress. The shading stress leaded to significant variations in starch, protein, and fat components in rice, which contributed to a decrease in peak viscosity and breakdown, but an increase in pasting temperature and setback. And then,those variations contributed to the significantly decrease in eating quality of cooked rice by increasing the hardness, but decreasing both stickiness and elasticity of cooked rice.


]]> <![CDATA[Effect of Dextran Modified Phosphate Fertilizer on the Winter Wheat Yield and Fertilizer Utilization Rate]]> 【Method】Glucose (monomer), maltose (2-polymer), oligomaltose (≈5-polymer) and polydextrose (≈20-polymer) were added to a mixture of phosphoric acid and potassium hydroxide at 1% addition to prepare glucose-modified phosphate fertilizer (GP), maltose-modified phosphate fertilizer (MP), oligomaltose-modified phosphate fertilizer (OP) and polydextrose-modified phosphate fertilizer (PP) using the reaction method, and the normal phosphate fertilizer (P) was prepared without the addition of dextran. The structural characteristics of the reaction between dextran and phosphate fertilizer were investigated by Fourier infrared transform spectroscopy (FTIR) and 31P nuclear magnetic resonance spectroscopy (31P NMR), and five treatments, P, GP, MP, OP, and PP, were set up according to the principle of equal phosphorus amount, and the control (CK) was applied with only nitrogen and potassium fertilizers. The effect of different polymeric dextran modified phosphate fertilizers on wheat yield and fertilizer utilization was investigated by soil column cultivation. 【Results】(1) Compared with P, the FTIR spectra of dextran modified phosphate fertilizer showed a new vibration peak at 975 cm-1, and the 31P NMR spectra showed a new displacement peak at 3.09-4.51, which might be due to the reaction between the hydroxyl group of dextran and phosphoric acid to form orthophosphate monoester. (2) Wheat yields were increased by 5.09%, 9.25%, 11.21% and 1.36% for the treatments with different polymerization degrees of dextran modified phosphate fertilizers (GP, MP, OP and PP) compared to P, respectively, mainly through the number of spikes, followed by the number of grains. (3) Compared with P, the total phosphorus uptake of wheat was significantly higher by 8.15%-21.35% in different polymerization degrees of dextran modified phosphate fertilizer treatments, among which, OP treatment was significantly higher than the other treatments. (4) The apparent phosphate fertilizer utilization rate of dextran modified phosphate fertilizer treatment was increased by 4.38-11.53 percentage points compared with P. The phosphate fertilizer bias productivity and phosphorus fertilizer agronomic efficiency were increased by 1.37%-11.21% and 1.60%-13.14%, respectively. the phosphate fertilizer utilization rate of both MP and OP treatments were significantly higher than P. (5) Compared with P, the soil fast-acting phosphorus content of dextran modified phosphate fertilizer treatment was significantly higher 10.22%-29.88%, and the OP treatment was significantly higher than the other dextran modified phosphorus fertilizer treatments. 【Conclusion】 Compared with common phosphate fertilizer, all dextran modified phosphate fertilizers with different polymerization degrees could improve wheat yield, promote the uptake and utilization of phosphorus in wheat, increase soil fast-acting phosphorus content and reduce phosphorus fertilizer fixation. With the increase of dextran polymerization degree, wheat yield and apparent phosphorus fertilizer utilization increased first and then decreased. The best effect of dextran polymerization on the modification and efficiency of phosphate fertilizer was achieved when the polymerization degree of dextran was 4-6.


]]> <![CDATA[Optimizing Nitrogen Fertilizer Rate for High-yield Maize in Black Soil Region Based on Ecological and Social Benefits]]> (urea) rates (0, 50, 100, 150, 200, 250, 300 kg N·hm-2) on maize yield, N uptake and N recovery efficiency (NUE), and further to evaluate the agronomic, economic, ecological and social benefits (N-derived gross caused by N application, private benefits of removed the N fertilizer cost, ecological benefits of removed environmental pollution cost such as active nitrogen loss and greenhouse gas emission, and social benefit of removed human health harm cost caused by environmental pollution, respectively) in different N rates by using life cycle assessment and comprehensive benefits analysis. The agronomically optimal N rate (AOR), privately optimal N rate (POR), ecologically optimal N rate (EOR) and socially optimal N rate (SOR) were calculated to evaluate the integrated benefits and determine the optimal N fertilizer rate for maize in black soil region. 【Result】Maize grain yields were significantly affected by N rates, which increased continuously with increasing N input and reached the yield plateau in 200 kg N·hm-2 treatment at both two experimental sites. Under this N rate, the average yields were 10.3 and 11.1 t·hm-2 at SKS and QYG across four experimental years, respectively. The N uptake of maize plants also showed increased trends with increasing N rates, and the highest value in 200 kg N·hm-2 treatment at SKS and QYG (151.9, 161.8 kg N·hm-2, respectively). The NUE of maize showed the highest values in 100 kg N·hm-2 treatment at both two experimental sites, the averages were 70.3% and 72.2%, respectively; and then, which decreased with increasing N rates. Based on 4-year results, the ecological and social costs caused by N fertilizer input increased exponentially with the increase of N application rate. The N-derived gross, private benefits, ecological benefits and social benefits of maize increased firstly and then decreased with the increase of N application rate. Based on the curve fitting calculation, the AOR, POR, EOR and SOR were estimated as 236, 225, 215 and 211 kg N·hm-2 at SKS, respectively, and which were 245, 235, 225 and 221 kg N·hm-2 at QYG, respectively. Under AOR condition, maize yields of 10.6 and 11.4 t·hm-2, the Nr losses of 44.4 and 46.8 kg N·hm-2 were obtained at SKS and QYG, respectively, while their ecological benefits were 8 786 and 10 271 yuan/hm2, and social benefits were 8 351 and 9 822 yuan/hm2, respectively. Compared with AOR, by reducing N inputs by 8.8% and 7.9% at SKS and QYG, respectively, EOR increased partial factor productivity from applied N by 9.1% and 8.1%, respectively, while reducing Nr losses by 11.7% and 11.0%, respectively. Compared with EOR, SOR further reduced N inputs by 10.6% and 9.6% at SKS and QYG, respectively, thus reduced Nr losses by 14.0% and 13.1%, respectively, while increasing social benefits by 124 and 119 yuan/hm2, respectively. 【Conclusion】Based on the comprehensive consideration with ecological and social benefits, the optimal N fertilizer rate was determined as 210-220 kg N·hm-2 for maize with yield of 10.5-12.0 t·hm-2, it is suggested that the optimal application of ecological or social benefits should be recommended for maize nutrient management in black soil area which could synergistically achieve the multiple goals for higher yields and NUE, improved ecological environment and human health.  


]]> <![CDATA[Effects of Biochar Combined with Dicyandiamide on Greenhouse Gases Emissions from Facility Vegetable Soil]]> Objective】This paper aimed to explore the comprehensive effects of biochar, dicyandiamide (DCD) and their combined application on the greenhouse gas (N2O, CO2 and CH4) emissions from facility soil, and to provide scientific basis for reducing the greenhouse gas emissions and green development of facility vegetable production system. 【Method】 In this study, the facility vegetable production system was used as the research object, and a total of six treatments were set up, including no nitrogen application (CK), traditional nitrogen application (CN), recommended nitrogen application (RN), recommended nitrogen application + biochar (RNB), recommended nitrogen application + DCD (RND), recommended nitrogen application + biochar + DCD (RNBD). A pot experiment method was applied to analyze the effects of soil greenhouse gas emissions, and the difference in greenhouse gas intensity (GHGI) and global warming potential (GWP) under different treatments. 【Result】Compared with the CN treatment, the rape yield decreased by 2.9%-29.3% under the recommend nitrogen treatments (RN, RN, RND and RNBD). However, under the same nitrogen application rate, the rape yield increased by 34.4% in the treatment of recommend nitrogen combined with biochar and DCD (RNBD), indicating that biochar and DCD showed a synergistic effect on rape yield increase (P<0.05). The recommend nitrogen treatments reduced the soil N2O emissions by 29.4%-76.5% in comparation with the CN treatment, especially the RND treatment showed the best effect. However, the recommend nitrogen treatments showed little effect on soil CO2 and CH4 emissions. Compared with the CN treatment, the total GWP under the recommended nitrogen treatments decreased by 4.3%-51.2%, and the RND treatment showed the best emission-reduction effect. In terms of GHGI, the difference among the recommended nitrogen treatments was not significant (P>0.05), and the RND treatment also showed the best emission-reduction effect. 【Conclusion】Under the same nitrogen application rate, the application of biochar alone or DCD alone had little effect on crop yield, but the combination of biochar and DCD could significantly increase the rape yield. Additionally, the combination of biochar and DCD could reduce the cumulative greenhouse gas emissions and GWP, but it was not superior to single application of DCD in the facility vegetable field.


]]> <![CDATA[Changes in Topsoil Organic Matter Content and Composition of a Gleyic Stagnic Anthrosol Amended with Maize Residue in Different Forms from the Tai Lake Plain, China]]> 】This study was to explore the changes in topsoil organic matter content and composition of a rice paddy with crop residue return in different forms, in order to provide sound information for crop residue utilization and paddy soil carbon sequestration.【Method】In June, 2015, untreated (CS), manured (CM) and pyrolyzed (CB) maize residue were returned at 10 t C hm-2, compared with no straw amendment (CK), to a paddy topsoil in Tai Lake plain, China. Topsoil (0-15 cm) samples were collected at rice harvest in November respectively of 2015, 2017 and 2019, and the changes in soil organic carbon (SOC) content and molecular composition were analyzed using 13C isotope and biomarker assays. 【Result】Compared to CK, topsoil OC was significantly increased by 8%-36% in 2015 and 2017 with all the residue amendment treatments, but increased by 24% only under CB in 2019,  with the SOC increases mainly from the input biochar. The abundance of lignin phenols in the topsoil under CS and CM peaked after 2-year amendment, and increased by 66% and 115% relative to CK, respectively. After 4 years, molecular abundance of plant-derived lipids increased significantly under all the amendments and the abundance ratio of plant- to microbe-derived lipids (PL/ML) and Shannon diversity of biomarkers (H’) were significantly enhanced. 【Conclusion】Compared to untreated and manured residue, pyrolyzed residue return enhanced SOC sequestration and the molecular diversity of organic matter, through the retention of plant-derived components in the paddy soil.


]]> <![CDATA[Cloning and Functional Analyses of MsCIPK2 in Medicago sativa]]> 】CIPKs are a group of important protein kinase involved in signaling pathway of plant in response to stress. They can form CBL-CIPK complex with CBL, to activate the expression of related responsive genes to cope with various abiotic stresses in cells. Exploration and study on the molecular mechanism of MsCIPK genes in alfalfa in response to abiotic stress will help to reveal the biological basis of stress resistance in alfalfa, and to provide new gene resources for alfalfa breeding with enhanced stress resistance. 【Method】The MsCIPK2 gene was cloned by using PCR, the sequence was analyzed by bioinformatics tools, and the expression level of MsCIPK2, MsCBL2, MsCBL6, MsCBL7 and MsCBL10 genes in various tissues were analyzed by using qRT-PCR. The pCAMBIA1302-GFP-MsCIPK2 vector was transiently expressed in tobacco leaf epidermal cells, and the subcellular localization was observed under laser confocal microscope. Yeast two-hybrid assay was used to analyze interaction between MsCIPK2 and four MsCBLs proteins. Agrobacterium rhizogenes was used to generate alfalfa hairy roots over-expressing MsCIPK2. qRT-PCRs were used to analyze the expression levels of related genes in transgenic hairy root lines. 【Result】The coding sequence of MsCIPK2 gene was obtained by using PCR, and it is 1230 bp in length, encoding 409 amino acids. The deduced MsCIPK2 protein contained typical ATP binding site, activation loop, NAF motif and PPI motif as for the CIPK family genes. The expression level of MsCIPK2 gene was the highest in roots, and the lowest in the flowers of alfalfa. Subcellular localization results showed that MsCIPK2 protein was localized in the endoplasmic reticulum. Yeast two-hybrid assays showed that MsCIPK2 protein interacted with MsCBL2, MsCBL6, MsCBL7 and MsCBL10 proteins, showing stronger interaction with MsCBL10 than with other MsCBLs. The expression levels of MsCBL2, MsCBL6, and MsCBL10 were the highest in roots in alfalfa, and the expression level of MsCBL7 was the highest in pods. qRT-PCR results showed that the expression levels of abiotic stress-associated genes ATPase, P5CS, CYP705A5, COR47, HAK5 and RD2 were significantly up-regulated in hairy roots over-expressing MsCIPK2. Under the treatment of 200 mmol·L-1 NaCl and 20% PEG, when compared with the control hairy root line, hairy roots over-expressing MsCIPK2 had lower MDA content, and higher POD activity, proline content and soluble sugar content. 【Conclusion】MsCIPK2 can interact with CBL protein, and responded to salt and drought stress in roots of alfalfa. Over-expression of MsCIPK2 can improve salt and drought stress resistance in alfalfa, and MsCIPK2 can be used as candidate gene for alfalfa breeding with improved abiotic stress resistance.


]]> <![CDATA[Maize Transcription Factor ZmEREB93 Negatively Regulates Kernel Development]]> y. AP2/EREBP (APETALA2/ethylene response element-binding protein) transcription factor (TF) plays an important role in plant growth, development, and stress response. Previous study showed that ZmEREB93 might regulate seed size as a target gene of ZmBES1/BZR1-5 TF. ZmEREB93 was cloned and used to analyze its expression pattern and function, which lays foundation to clarify the function and mechanism of ZmEREB93 regulating seed size. 【Method】The full length of ZmEREB93 was cloned from maize inbred line B73 by PCR. The characters of nucleotide and amino acid sequences were analyzed by informatic methods. Subsequently, the tissue expression specificity of ZmEREB93 was analyzed via quantitative real time PCR (qRT-PCR). The expression vector in plant and yeast was constructed and used for subcellular localization and transcription activation assay, respectively. ZmEREB93 was transformed into Arabidopsis mediated by agrobacterium transformation. The seed phenotype of transgenic lines was analyzed. Finally, the potential target genes of ZmEREB93 were screened by chromatin immunoprecipitation sequencing (Chip-seq）and co-expression analysis, and further confirmed by yeast one hybrid (Y1H). 【Result】The ZmEREB93 gene was cloned by PCR. Sequence analysis showed that ZmEREB93 had no intron and an 618bp ORF, encoding 205 amino acids with a highly conserved AP2 domain and belongs to the ERF subclade of AP2 family. The results of RT-qPCR showed that the ZmEREB93 gene highly expressed in kernels of 15 and 25 days after pollination (DAP), and slightly expressed in stem and root, but did not express in tassel, silk and bract. The expression level of ZmEREB93 was the highest in 25 DAP kernels reached 11 times of that in 15 DAP kernels. The results of transcriptional activation and subcellular localization assay exhibited that ZmEREB93 protein had no transcriptional activation activity in yeast cells and was localized in the nucleus, respectively. Compared to wild type, the seeds of transgenic lines were significant smaller and showed lower thousand-seed-weight. Chip-seq and co-expression analysis suggested that the Zm00001d013611, Zm00001d006016, Zm00001d027448 and Zm00001d03991 genes were candidate target genes regulated by ZmEREB93 TF. The result of Y1H showed that ZmEREB93 directly bind to Zm00001d013611 promoter. 【Conclusion】Maize ZmEREB93 TF specifically expressed in seeds and negatively regulated seed size.


]]> <![CDATA[QTL Mapping of Thousand-Grain-Weight and Its Related Traits in Zhou 8425B × Xiaoyan 81 Population and Haplotype Analysis]]> 】Zhou 8425B is one of the most important founder parents in China and Xiaoyan 81 is an elite cultivar with high yield and good quality. Thousand-grain weight (TGW) is an important factor that affects wheat yield. Identification of QTL associated with grain related traits from Zhou 8425B and Xiaoyan 81, and haplotype analysis of these QTL in wheat cultivars from different ecological regions would be beneficial for yield improvement by molecular marker-assisted selection.【Method】In this study, a RIL population (F8) derived from Zhou 8425B × Xiaoyan 81 was planted in Yangling during 2015 and 2016 cropping seasons to evaluate grain related traits. Using a high-density genetic map constructed by 90K SNP markers, QTL mapping of thousand-grain weight, grain length, grain width and thickness was performed under three environments. Simultaneously, the KASP markers linked to the identified QTL were developed and molecular detection was carried out among 479 wheat accessions worldwide. Moreover, haplotype analysis of target QTL was performed in 106 current wheat commercial cultivars from Yellow and Huai River Valley Winter Wheat Region selected from 479 wheat accessions.【Result】A total of 22 QTL on 8 chromosomes were detected, and the phenotypic variation explanation (PVE) ranged from 4.77% to 19.95%. Among them, 12 QTL are major QTL (PVE>10%) and Qkgw.nwafu-6B is a new QTL. QTL on chromosomes 4A, 6A, 6B, and 7D were detected in multiple environments, of which, the QTL on chromosomes 4A and 7D are same as previously reported ones. Compared to TaGW2-6A using molecular detection, both Zhou 8425B and Xiaoyan 81 carried the same allele of TaGW2. Based on haplotype result of Qkgw.nwafu-6A, Zhou 8425B and Xiaoyan 81 were placed in different groups. Therefore, Qkgw.nwafu-6A tends to be a new one. Haplotype analysis showed that there were five haplotypes for Qkgw.nwafu-6A and there were eight haplotypes for Qkgw.nwafu-6B. 6A_h1 and 6B_h6 accounted for over 20% in different ecological regions. In addition, a co-segregated KASP marker was developed for Qkgw.nwafu-6B and was significantly associated with the grain weight in the 479 wheat accessions.【Conclusion】Qkgw.nwafu-6A and Qkgw.nwafu-6B are possible new QTL associated with thousand-grain-weight, and 6A_h1 and 6B_h6 are likely favorable haplotypes. A molecular marker KASP_IWA349 co-segregated with Qkgw.nwafu-6B was developed and will be useful for marker assisted selection.


]]> <![CDATA[Leaf Stomatal Close and Opening Orchestrate Rhythmically with Cell Wall Pectin Biosynthesis and Degradation]]> 】Comparing on differential expression proteins between stomatal closing and opening at different leaf stomata-densities, it is to be revealed how pectin metabolism regulates stomata closing and opening. The result will play an essential role in understanding how stomata functions to environment adaptation. The result will play an essential role in understanding how stomata functions to environment adaptation.【Method】Vectors, either over- or  inhibiting-expression of StEPF-2 (Solanum tuberosum EPIDERMAL PATTERNING FACTOR 2) in vivo were constructed. The fusing genes were transformed into Solanum tuberosum cultivar Kexing 1. Transgenic potato lines, either rise or lower at leaf stomatal density were generated. Gene and protein expression profiles of leaves at various stomatal densities were assayed via RNA-seq and iTRAQ. Comparing differentiation expression proteins, pectin metabolic enzymes driving stomatal movement under light and darkness were identified and confirmed by the Pulldown and LC-MS/MS. A pectin metabolism pathway regulating stomatal movement was to be proposed.【Result】At least 14 protein families, drive stomata closing and opening involved in pectin metabolism of the guard cell wall during stomatal mature. Five protein families were detected and confirmed only in the stomatal-closed leaves under darkness, including polygalacturonase inhibitor proteins (PGIP) and Rhamnose synthase (RHM) for RG side-chain biosynthesis. Four protein families, polygalacturonase (PG), pectate lyase-like (PLL), pectinmethylesterase (PME) and α-galactosidase (AGAL) were identified only in leaves at various stomatal densities under light. Additionally, five protein families were concurrently identified in both leaves of stomata closing and opening, including pectinacetylesterase (PAE) and subtilase (SBT).【Conclusion】Under light, PMEs catalyze pectin demethylesterification, afterwards, pectin was exo- and endo-hydrolyzed by PG, PLL and AGAL. Pectin losing structure was split under turgor, results in stomatal opening. Reversely, under dark, PGI inhibited pectin hydrolysis. Pectin side-chain biosynthesis was promoted by RHM. Therefore, stomata kept closing due to structurally-complete pectin with voluntary expending function.


]]> <![CDATA[Function of FCS-Like Zinc-finger Protein OsFLZ18 in Regulating Rice Flowering Time]]> 】Flowering time is an important agronomic trait which determines the yield and regional adaptability of rice, but the underlining molecular regulatory mechanism need further study. FCS-like Zinc finger proteins (FLZs) are a class of plant specific regulatory proteins which play essential roles in plant growth and stress reponse, but their functions in regulating flowering time have not been reported. This study aims to investigate the potential function of FLZ proteins in rice flowering time control.  The finding will broaden our understanding on the molecular regulatory mechanism of rice flowering time .and provide new theoretical basis and gene resource for rice breeding. 【Method】Based on the target sequences published in RGAP database, OsFLZ18 overexpression vector and CRISPR-Cas9 vector were generated and introduced into Japonica variety Nipponbare by Agrobacterium tumefaciens-mediated genetic transformation assay. Homozygous CRISPR knockout mutants were screened by PCR and sequencing analyses. The quantitative real-time PCR (qRT-PCR) assay was used to examine the spatial-temporal expression and diurnal rhythmic expression of OsFLZ18, as well as the effects of OsFLZ18 on the transcription of several known flowering time-related genes. Yeast two-hybrid assay (Y2H) was used to test the interaction between OsFLZ18 and the flowering time-related regulatory proteins.【Result】OsFLZ18 was ubiquitously expressed in various rice tissues, with the highest expression level in 14 day-old seedling, followed by leaf sheaths and leaf blades at the tillering stage, and stem and young panicles at reproductive stages. The OsFLZ18-CRISPR vector was constructed and transformed into Nipponbare. Two independent homozygous OE lines (OE-2, OE-3) with higher OsFLZ18 expression level and two homozygous mutants (CRISPR-21, CRISPR-25) were selected for further study. Phenotypic observation showed that the OE lines flowered later than the wild-type plants under both natural long-day and short-day conditions in Guangzhou, while the CRISPR lines had no obvious differences in heading date when compared to the wild-type plants. The expression levels of Ehd1, Hd3a and RFT1 were significantly decreased in OE-2 plants compared with those in the wild-type plants under artificial short-day conditions, but no significant difference in the expression level of Hd1 was observed between them. The results of Y2H experiment showed that OsFLZ18 interacted with OsMADS51, a positive regulator of rice flowering time. Furthermore, OsFLZ18 exhibits a diurnal rhythmic expression profile, showing lower expression levels in the daytime and higher expression levels at night with a peak at midnight. 【Conclusion】Overexpression of OsFLZ18 delays rice flowering time.


]]> <![CDATA[Cloning and Analysis of Key Genes for Vitamin C Synthesis in Cucumber Fruit]]> To identify the location, quantity and expression characteristics of genes involved in regulating the synthesis of vitamin C (Vc) by  L-galactose pathway in cucumber fruits, and to clone the key genes, aiming to lay a foundation for the regulation of vitamin C synthesis in cucumber.【Method】According to the reported Vc-related genes within the L-galactose pathway in Arabidopsis, the encoded amino acid sequence was used for BLAST in Cucumber 9930_ V2 reference genome database. TBtools software was used to map the gene position on cucumber chromosomes. The expression of these genes in two cucumber accessions with significant differences in fruit Vc content was analyzed by qRT-PCR. The homologous genes encoding rate limiting enzymes GDP-L-galactose phosphorylase (GGP) and GDP mannose -3'5'- epienzyme (GME) were cloned by PCR amplification, and the sequence differences of these genes in cucumber with high Vc and low Vc were analyzed by sequencing. Phylogenetic tree was constructed to analyze the relatedness cucumber GME, GGP and homologs in other species.【Result】Twenty one homologous genes involved in the synthesis of Vc related enzymes PMI、PMM、GMPase、GME、GGP、GPP、GalLDH、GalLDH in L-galactose pathway were compared in cucumber were obtained by BLAST, they were distributed on seven chromosomes, with the most numbers on chromosome 5 and chromosome 1. By analyzing the expression of these genes in R48 (with low Vc）and CG45 (with high Vc), it was found that the genes regulating PMI, PMM, GMPase, GME and GalLDH were significantly different between the two materials. The sequence analysis of vitamin C synthesis rate-limiting enzyme GGP and GME related genes showed that the full length of CsGME2 gene was 3537 bp in R48 and 3541 bp in CG45. There were multiple SNP site and Indel difference between the two materials, one mutation site was located in the CDS region, and result in the amino acids changes. Through the analysis of the protein properties of rate limiting enzymes GME and GGP regulating vitamin C synthesis, it is found that the protein properties of GME and GGP in different species are not significantly different, they are hydrophilic proteins and their functions are relatively conservative. Evolutionary tree analysis found that the clusters with close genetic relationship among different species are highly conservative during evolution.【Conclusion】Twenty one L-galactose pathway related genes of cucumber Vc synthesis were identified, which are distributed on seven chromosomes. It is speculated that the key enzymes PMI, PMM, GMPase, GME, GalLDH and GGP may affect the Vc content in cucumber fruits. The functions of key enzymes GME and GGP regulating the rate limiting step of vitamin C synthesis are relatively conservative. The SNP site on CsGME2 gene in the two materials of high Vc and low Vc results in changes in amino acid sequence.


]]> <![CDATA[Inhibition and Interaction of <i>Pleurotus eryngii</i> Polysaccharide and Its Digestion Products on Starch Digestive Enzymes]]> 】Investigation on the basic physicochemical properties of Pleurotus eryngii polysaccharide (PEP) and its related effects on diffusion and adsorption of glucose were conducted in the present study. PEP mimetic digestion products (D-PEP) were prepared using an in vitro stimulated digestion model to explore the effects of PEP and D-PEP on the digestive enzymes activities associated with glucose metabolism, as well as the interaction between PEP/D-PEP and α-glucosidase. 【Method】Firstly, the basic physicochemical properties of PEP were detected based on the methods in previous studies. Then the inhibitory effects of PEP/D-PEP on α-amylase and α-glucosidase activities were evaluated by DNS method and 4-Nitrophenyl α-D-glucopyranoside (PNPG) method, respectively. Finally, the relationship between PEP/D-PEP and α-glucosidase was studied with the utilization of the fluorescence spectroscopy technique. 【Result】Results revealed that PEP displayed great potential on the solubility, swelling property, water and oil holding capacities, and favorable inhibition on glucose diffusion and adsorption. Moreover, PEP had obvious inhibitory effects on maltase and α-glucosidase, while it did not suppress the activity of α-amylase. Specifically, PEP with its concentration of 4 mg?mL-1 exhibited 77.20±2.71% inhibition ratio on maltase activity, while (78.91±0.51) % inhibition ratio on α-glucosidase activity. However, the digestion product D-PEP showed significant inhibition on the activities of all these three enzymes, with 4 mg?mL-1 of D-PEP inhibiting α-amylase, maltase, and α-glucosidase by (84.08±1.79) %, (20.58±1.20) %, and (95.58±0.12) % respectively. The outcomes of fluorescence spectroscopy showed that the endogenous fluorescence of α-glucosidase was gradually decreased along with the increasing of the PEP/D-PEP concentration, and the quenching of the endogenous fluorescence of α-glucosidase by PEP/D-PEP was mainly static quenching, with the number of binding sites greater than or equal to 1. 【Conclusion】In summarize, D-PEP not only inhibited maltase and α-glucosidase activities but also showed great potential inhibition effects on α-amylase activity compared with PEP. Herein, D-PEP displayed stronger inhibitory effect on amylase and could be considered affect glucose metabolism to a certain degree.


]]> <![CDATA[Effects of Artificial Fruit Thinning on Sugar and Acid Content and Expression of Metabolism-related Genes in Early Fruit Development of ‘Beni-Madonna’]]> 】 ‘Beni-Madonna’, also known as ‘Hongmeiren’, is favored by people because of its excellent quality. Fruit thinning is a technique commonly used by ‘Beni-Madonna’ to improve fruit quality in the process of agricultural production. It can not only significantly increase the volume of fruit, but also increase the content of soluble solids in the fruit. However, the specific mechanism of fruit thinning to increase the content of soluble solids in the fruit of ‘Beni-Madonna’ is still unclear. Therefore, in this study, Four-year-old ‘Beni-Madonna’ tangor (Citrus nanko ′ C. amakusa) plants, with trifoliate orange (Poncirus trifoliata) as a base rootstock and Ponkan as an intermediate stock, were used as experimental materials to explore the specific mechanism of fruit thinning affecting the change of sugar and acid content in fruits. 【Method】Fruit thinning was carried out at the young fruit stage of ‘Beni-Madonna’ fruit. The horizontal and vertical stems of fruit thinning and non fruit thinning were measured every half a month or so. Samples were taken back and the single fruit weight and sugar and acid content of each treatment were measured. After grinding into powder with liquid nitrogen, the activities of sugar and acid metabolism related enzymes and the relative expression of their corresponding coding genes were measured at the time when the sugar and acid content were significantly different. 【Result】Fruit thinning significantly increased the horizontal and vertical stems and single fruit weight of ‘Beni-Madonna’ fruit in the middle and late stages of fruit growth, significantly accelerated the degradation rate of citrate content, but did not affect the final citrate content at fruit maturity, significantly increased the fruit glucose and sucrose content, but had no significant effect on fructose content. Fruit thinning significantly increased the activities of sucrose synthase (SSⅡ, synthesis direction), sucrose synthase (SSⅠ, decomposition direction), sucrose phosphate synthase (SPS) in sucrose metabolism and cytosolic aconitase (Cyt-ACO), cytoplasmic isocitrate dehydrogenase (ICDH) and glutamine synthetase (GS) implicated in citric acid catabolism. In addition, fruit thinning significantly promoted the early relative expression of CitSS3 and the relative expression of CitSPSs at all stages in the process of sucrose metabolism, and the relative expression of CitACO3, CitNADP-IDH1, CitACLα1/β, CitGAD1 and CitGSs in the process ofcitric acid metabolismin the early and middle stages. 【Conclusion】Artificial fruit thinning mainly promotes the accumulation of soluble sugar in fruit by enhancing the enzyme activity of sucrose phosphate synthase in the process of sucrose anabolism, improves the activity and gene expression level of related enzymes in the process of citric acid catabolism, and accelerates citric acid degradation, thus playing an important role in improving fruit quality.


]]> <![CDATA[Resistant Evaluation of 84 Apple Cultivars to <i>Alternaria Alternata f.sp. mali </i>and Genome-wide Association Analysis #br#]]> Alternaria alternata f.sp. mali is a main disease occurring in Chinese apple orchard, which seriously threatens the yield and quality of apples. The aim of this research is to identify apple cultivars and genes with high resistance to Alternaria alternata f.sp. mali, thus providing basis for disease resistance breeding of apples.【Methods】 In this study, the isolated Alternaria alternata f.sp. mali strain was used to inoculate leaf of 84 apple cultivars. To evaluate the resistance of apple cultivars to leaf spots, cluster analysis was carried out from two aspects of lesion area and lesion area growth rate. Genome-wide association study was performed based on the lesion area.【Results】Statistical analysis of lesion area showed significant diversity of 84 apple cultivars in resistance to Alternaria alternata f.sp. mali. Most apple cultivars were susceptible or resistant to Alternaria alternata f.sp. mali, while only a few cultivars were highly resistant and highly susceptible. A total of 1243071 high-quality SNP loci were finally obtained, among which 6 SNP loci showed significant aboriginality level (P ≤ 0.0000001).【Conclusion】We identified seven highly resistant cultivars and two susceptible varieties from 84 apple cultivars. In addition, six loci and seven key candidate genes significantly associated with the disease resistance were identified, among which the SNP located on chromosome 5 at 9336893 bp was the most significantly associated locus. The seven candidate genes included Integrin-linked protein kinase (MD05G1054300), FMN-linked oxidoreductase superfamily protein (MD05G1054400), GATA transcription factor (MD05G1048600), and B-box zinc finger family protein (MD00G1039900).


]]> <![CDATA[Differentiation of Porcine Muscle Stem Cells in Three-dimensional Hydrogels]]> , and to provide guidance for inducing muscle stem cells to differentiate into muscle tissue in vitro.【Method】 Some porcine muscle stem cells were respectively induced to differentiate under the conditions of 2D and 3D (2D condition means culturing cells in cultured dishes; 3D condition means culturing cells in hydrogels). The RNA and protein samples of porcine muscle stem cells cultured in 2D were collected respectively at proliferation, pre-differentiation, early differentiation, mature differentiation and late differentiation, and those in 3D were also collected respectively at day 7 and day 14 of differentiation. Then, RT-qPCR was used to compare the expression levels of the myogenic-related genes including the genes of MYOG, CAV-3, MyHC-slow, and MyHC-2a, under 2D and 3D differentiation conditions. Correspondingly, Western Blot was used to detect the expression levels of MyHC protein and MYOG protein in the two conditions. Moreover, immunofluorescence staining was used to observe the myotubes formed in cell culture dishes and hydrogels. Further, we analyzed the amino acid content and composition of the cultured muscle tissue by an amino acid automatic analyzer at day 14 of differentiation. 【Result】 The porcine muscle stem cells started to fuse to form myotubes at day 3 of differentiation in 2D. Myotubes formed in 2D matured at day 7 and divorced from culture dish afterwards. The porcine muscle stem cells were still globe and had low expression of MYOG and CAV-3 at day 7 of differentiation in 3D. Multinucleated myotubes formed at day 14 and the expression of MYOG and CAV-3 reached levels of 2D differentiation. The cells in hydrogels had higher expression of terminal differentiation genes MyHC-slow and MyHC-2a than the cells in culture dishes. The expression of MyHC-slow was 12 times that at day 7 in 2D and the expression of MyHC-2a was 4 times that at day7 in 2D, but the expression of MyHC protein was only 1/6 that at day 7 in 2D. Amino acid analysis results showed that the contents of 17 hydrolyzed amino acids in cultured muscle tissue were all lower than those in pork, and the radio of essential amino acids was also lower in cultured muscle tissue, but the radio of flavor amino acids was higher. 【Conclusion】 Porcine muscle stem cells can differentiate into myotubes in 3D collagen hydrogels in vitro, and the 3D conditions are positive to the expression of myogenic differentiation related genes, but further research is needed to achieve high expression of MyHC protein. The flavor amino acid content of the muscle tissue cultured in this way is high, which may mean good flavor.


]]> <![CDATA[Effects of Chilling on Chlorophyll Fluorescence Imaging Characteristics of Leaves with Different Leaf Ages in Tomato Seedlings]]> Objective】This study analyzed the characteristics of chlorophyll fluorescence imaging of the 2nd (mature) and 4th (newly born) leaves of tomato seedlings in response to chilling stress, aiming to probe the mechanism by which leaves with different ages adapted to chilling stress in tomato seedlings.【Method】In this study, Solanum lycopersicum L. cv Zhongshu No.4 was used as the research material. The tomato seedlings in the 4-leaf stage were treated at chilling (8℃, 200 μmol·m-2·s-1) for 15 d and then recovered at normal temperature (26℃ day/20℃ night, 500 μmol·m-2·s-1) for 1 d. Chlorophyll fluorescence imaging of the whole seedlings was measured at different stages of treatment, and the characteristics of chlorophyll fluorescence imaging of the 2nd and 4th leaves were compared. 【Result】The results showed that the relative area of photosynthetically active regions (RAP) on the 4th leaves decreased slowly during the first 5 d of the chilling stress, while the RAP on the 2nd leaves and the whole plants decreased steadily during the whole chilling treatment. The RAP recovered completely after 1 d of recovery. Under chilling treatment, the relative area of fluorescence active regions (RAF) for quantum yield of regulatory energy dissipation (Y(NPQ)), quantum yield of nonregulatory energy dissipation (Y(NO)), and nonphotochemical quenching (NPQ) showed similar changes as that of RAP. However, the RAF of effective PSII quantum yield (Y(II)) and coefficient of photochemical quenching (qP) were significantly lower than RAP. Maximum PSII quantum yield (Fv/Fm), Y(NPQ), and NPQ decreased while Y(NO) increased sharply in the photosynthetically active region in tomato seedlings during the first 5 d of the chilling treatment. In the following days, the Fv/Fm remained unchanged, whereas Y(NPQ) and NPQ increased and Y(NO) decreased. However, Y(II) declined sharply 1 d after chilling stress and then remained unchanged. Interestingly, qP in the photosynthetic active region of the 4th leaves decreased only slightly after 1 d of chilling treatment, and then maintained higher than that before treatment. However, qP of the 2nd leaves increased significantly on the 5th day and then decreased rapidly. Overall, the Fv/Fm, Y(II), Y(NPQ) and qP in the 4th leaves were higher than those in the 2nd leaves, whereas the Y(NO) were relatively lower in the 4th leaves.【Conclusion】The study found that tomato seedlings responded to chilling stress by decreasing the area of photosynthetically active regions. The regulatory nonphotochemical quenching, which plays a central role in photoprotection, was inhibited in the early stage, but gradually increased during the later stage of chilling treatment. Mature leaves adapted to chilling stress likely by decreasing the size of photosynthetically active regions, while higher capacities of PSII photochemistry and thermal dissipation were maintained in the newly born leaves in response to chilling stress. Protection of the shoot apex and the newly born leaves may be the priority of tomato seedlings in response to chilling stress. For newly born leaves, chilling induced the closure of some active PSII reaction centers, but improved the operating efficiency of the remaining active PSII reaction centers, which is potentially beneficial for the recovery of photosynthetic activity during the recovery period.


]]> <![CDATA[Effects of Different Biochar Application Rates on Soil Aggregate Characteristics and Organic Carbon Contents for Film-Mulching Field in Semiarid Areas]]> 】Studying the effects of long-term plastic film mulching farmland combined with different biochar inputs rates on soil aggregate stability and organic carbon in northwest China, in order to provide a scientific basis for improving the soil fertility and maintaining the sustainability of crop production for film-mulching field in semiarid regions. 【Method】Based on continuous years of double ridge furrow film mulching (D), full film double ridge furrow mulching planting and traditional flat without film mulching planting were set as the main treatment, four biochar input rates (no returning (N), 3 t·hm-2 (L), 6 t·hm-2 (M), and 9 t·hm-2 (H) ) were set as the secondary treatment respectively to investigate the effects of different biochar inputs rates on soil aggregate distribution, aggregate stability, aggregate organic carbon and maize yield.【Result】The results showed that the film mulching can significantly (P<0.05) increase the soil mechanically stable (6.1%-8.7%) and water-stable (15.9%-83.6%) macro-aggregate contents and maize yield (35.0%-41.8%). Under the film mulching planting, biochar inputs treatments could significantly (P<0.05) increase mechanically macro-aggregate and water macro-aggregate by 6.8% and 29.6% on average, respectively, and the effects gradually increased with the increase of biochar inputs rate. In addition, biochar inputs could also increase the soil organic carbon and aggregate organic carbon content in film mulching farmland, and the effects under DH (9 t·hm-2) were the better than other treatments, with an average increased by 13.9% and 25.9%, respectively. Maize yield was significantly correlated with biochar addition rates ( λ=0.42, P<0.001 ), and DH had the highest yield with 12.8 t·hm-2. 【Conclusion】Biochar input can significantly improve soil aggregrate characteristics and organic carbon content in plastic film mulching farmland, thus increase the maize yield and promote soil carbon sequestration, especially with 9 t·hm-2.


]]> <![CDATA[Effects of Long-Term Film Mulching and Application of Organic Fertilizer on Yield and Quality of Spring Maize on the Loess Plateau]]> 【Objective】To investigate the effects of long-term film mulching and application of organic fertilizer on yield, quality, dry matter accumulation and nitrogen uptake of spring maize through long-term localized field experiments.【Method】The long-term experiment began in 2009 at the Changwu Agri-Ecological Station, and the samples were collected in 2020 and 2021.The field experiments were conducted with four treatments: F (mulching, no N), N (no mulching, N 225 kg·hm-2), FN (mulching, N 225 kg·hm-2), FSN (mulching, N kg·hm-2 and apply organic fertilizer). Plant samples for measuring total biomass were collected at silking stage (R1) and harvest stage (R6). The samples were divided into different parts as required, and the total N contents were determined. Crude protein, crude fat and crude amylum concentrations of maize grain were determined at harvest. 【Result】(1) Mulching under nitrogen application significantly increased the yield of spring maize, while additional application of organic fertilizer under mulching further increased the yield. Compared with the control, the N treatment increased the yield by 106%-176%. The FN treatment increased the yield by 21%-75% on this basis, and the FSN treatment was further increased by 5.6%-8.4%. (2) Mulching under nitrogen application significantly increased the dry matter accumulation and N uptake of spring maize, and the two indicators were further improved after the application of organic fertilizer. (3) The crude protein content of the N treatment was 8.67%-8.94%, while the crude protein content of the FN treatment increased to 8.99%-9.34%. The crude protein content of the FSN treatment was not further improved. There were no significant differences in crude fat and crude amylum content between the treatments. 【Conclusion】Film mulching (FN) significantly increased the yield and crude protein content of spring maize. The application of organic fertilizer under the condition of film mulching (FSN) further increased the yield on the basis of maintaining the crude protein content of the grain, and realized the high yield and high quality of spring maize.

]]> <![CDATA[Environmental Risks Assessment of Livestock and Poultry Non-point Source Pollution Based on Arable Land Carrying Capacity: A Case Study of Danjiangkou Reservoir Region in Shiyan City]]> Objective】Danjiangkou reservoir area was the core water source area of the middle route of the South-to-North Water Transfer Project, It was the premise to strengthen the risk control of livestock and poultry manure to comprehensively understand the spatial difference of livestock and poultry manure and its potential threat to ecological environment. 【Method】This paper used the livestock manure environmental risk assessment model to quantitatively analyze the source structure of livestock and poultry manure in different areas of Shiyan city in 2020, and comprehensively evaluated the environmental risk from the perspective of the balance between planting and raising. 【Result】The results showed that the total amount of livestock and poultry manure reached 306.85×104 t in 2020, and it was mainly distributed in Yunyang district, Danjiangkou city and Fangxian county. COD production was the highest (57.00×104 t), followed by TN (2.63×104 t), and TP production was less (0.65×104 t). The total equivalent standard


 pollution load was 15.532×1010 m3, and the source structure was obviously inconsistent in different regions. TP was the primary pollutant in livestock and poultry breeding, and its equivalent standard pollution load accounts for 41.68% of the total load, followed by TN with the pollution load rate of 33.85%, and the lowest equivalent standard pollution load rate of COD was 24.47%. Cattle was the primary source of non-point source pollution in livestock and poultry production in Shiyan area, contributing 49.47% to the total pollution load of the equivalent standard, which followed by poultry (21.60%). According to the result of environmental pollution risk assessment, the load of animal excretion per hectare of arable land in Shiyan city was 10.15 t·hm-2，the alarm value was 0.338 and the risk level was Ⅰ, indicating the environmental pollution was "no risk". The load intensity of TN and TP was 90 and 20 t·hm-2, respectively, and the environmental risk index was 1.023 and 1.223, but there were obvious spatial differences among regions. More than half of the whole city has the potential pollution risk of livestock and poultry breeding, mong which Maojian district and Yunyang District were the most serious. With phosphorus as the measurement standard, the total amount of breeding in Shiyan city was close to saturation, the total amount of livestock and poultry must be reduced by 98.51× 104 pigs equivalent on the existing basis.【Conclusion】It was of great significance to maintain a reasonable scale of poultry breeding and take measures of pollutant abatement in order to promote the balance of planting and breeding and orderly development of livestock and poultry breeding in Danjiangkou reservoir area.

]]> <![CDATA[Characteristics of the Variation in Soybean Yield and Soil Nitrogen Distribution in Brown Soil under Long-term Fertilization]]> 1), manure at a low rate combined with chemical fertilizer (M1N, M1NP, M1NPK); single application of manure at a high rate (M2), manure at a high rate combined with chemical fertilizer (M2N, M2NP, M2NPK). The evolution of soybean yield under long-term different fertilization and the effects of 39-year crop rotation fertilization on nitrogen uptake of soybeans and soil nitrogen accumulation distribution at harvest stage were analyzed.【Result】Compared with the CK treatment, the average yield of soybean under each fertilization treatment was significantly improved, and those at treatments with manure at low and high rate were higher than those at treatments with chemical fertilizer alone, and the average yield at M1NPK and M2NPK treatments were the highest with 3 147 and 3238 kg·hm-2, respectively, which were 9.5% and 12.7% higher than that at NPK treatment. The results of the grey-linear regression showed that application with manure simply or combined with chemical fertilizer significantly increased the interannual yield compared to that with chemical fertilizer alone. The variation coefficient of soybean yield at treatments with manure at the low rate was the lowest with a high yield stability. The yield sustainability index (YSI) was higher ranging from 0.41 to 0.51, which was higher than that at treatments with manure at the high rate. Combined application of manure increased the contribution of fertilization to soybean yield without significant difference between treatments with manure at the low and high rate. After application of manure for 39 years, the soybean N uptake increased compared with the treatments with single chemical fertilizer, which was the highest at M1NPK treatment being 301.5 kg·hm-2. With application of manure at the low rate, soil mineral N mainly accumulated in 0-60 cm soil layers, and its concentration at 60-100 cm soil depths was low. The mineral N concentration in the 0-80 cm soil layers with application of manure and chemical fertilizer were higher than those at M1 treatment, which would provide available N for crop, but reduced the mineral N concentration in deep 80-100 cm layers leading to less N loss by leaching. Among them, the mineral N concentration in the 0-60 cm soil layers was the highest at M1NPK treatment, whereas in the 60-100 cm soil layers, the mineral N concentration showed a significant decrease trend with the soil depth increasing, compared with M2NPK treatment of the block with manure at the high rate. The soil total N and microbial biomass N were increased in the top 20 cm soil layer after fertilization with manure and chemical fertilizer for 39 years, which were higher than that in the 20-40 cm soil depth. The total N concentration in the 0-20 cm soil layer at M1NPK and M2NPK treatments increased by 13.9% and 5.5%, respectively, compared with NPK treatment, where the microbial biomass N concentration increased by 32.6% and 92.1%, respectively.【Conclusion】Long-term fertilization affected crop yield, N uptake, and soil N distribution. In the maize-maize-soybean rotation system in the brown soil area of Northeast China, application of N, P, and K fertilizer combined with manure at a low rate (13.5 t·hm-2) in the maize season, and the lonely application of N, P, and K fertilizer in the soybean season increased the soybean yield, improved the yield stability and sustainability, changed the soil N distribution and accumulation, and thus influenced the soybean N uptake. The increase of soil total N and microbial biomass N concentration at soybean harvest under long-term application of manure at a low rate increased the soil N supply, meanwhile the reduction of mineral N accumulation in deep soil reduced the risk of N loss by leaching, which is conducive to the sustainable and green production of soybean and is a reasonable fertilization method for this rotation system.


]]> <![CDATA[<p class="MsoNormal"> Effects and Mechanisms of Exogenous GABA against Oxidative Stress in Piglets]]> ing apoptosis signaling pathways in it, which will provide scientific basis for the application of γ-aminobutyric acid as animal stress regulator. 【Method】 Based on the successful establishment of oxidative stress model in piglet and rat hippocampal neurons, the effects of exogenous GABA on piglets under oxidative stress, including oxidative / antioxidant related indexes, growth performance related indexes and GABA receptor in serum and hippocampus, along with the GABA receptor and apoptosis signal pathway related indexes in hippocampal neurons were investigated. 【Result】 The serum MDA levels of piglets in the low, medium, and high concentration GABA feeding groups (LD+OS; MD+OS; HD+OS) were extremely significantly lower than those in the oxidative stress (OS) group (P <0.01), the GSH level was extremely significantly higher than that in the OS group (P <0.01), and the T-AOC level in the HD+OS group was extremely significantly higher than that in the OS group and control group (P <0.01. And the high concentration (100mg·kg-1  BW) of GABA more decreased the MDA level and more increased the GSH level in serum of piglets than those of the low concentration (20mg·kg-1  BW) and middle concentration (60mg·kg-1  BW) of GABA. Therefore, the follow-up study only investigated the anti-oxidative stress effect and mechanism of 100 mg·kg-1  BW. The daily gains of piglets at 0-7 days, 8-14 days and 0-28 days in the OS group were extremely significantly lower than those in the control group (P <0.01)，the daily gains of piglets at 0-7 days, 8-14 days and 0-28 days in the HD+OS group were extremely significantly higher than those in the OS group (P <0.01), the daily gain of piglets aged 15-28 days in the OS group was significantly lower than that in the control group (P <0.05)，the daily gain of piglets aged 15-28 days in the HD+OS group was extremely significantly higher than that in the OS group (P <0.01). The above results showed that the 100 mg·kg-1 BW GABA feeding extremely significantly increased the daily gain of piglets. There was no significant difference in the diarrhea rate of the control group, OS group and HD+OS group in the first, middle and late stages (P >0.05). The MDA level of hippocampus in the OS group was significantly higher than that of the control group and HD+OS group (P <0.01), the T-AOC and GSH levels were extremely significantly lower than the other two groups (P<0.01), which showed that GABA feeding would improve the antioxidant capacity of hippocampus. The levels of GABAA and GABAB receptors in the hippocampus of the HD+OS group were extremely significantly higher than those in the control group and the OS group (P <0.01), which showed that GABA feeding increased the levels of GABAA and GABAB in hippocampus. The Bcl-2 level in the hippocampus of the OS group was significantly lower than that of the control group (P <0.05), and the Bax and Caspase-3 levels were extremely significantly higher than those of the control group (P <0.01). The Bcl-2 level of the HD+OS group was extremely significantly higher than that of the OS group (P <0.01), the Bax level was extremely significantly lower than that of the OS group (P <0.01), and the Caspase-3 level was significantly lower than that of the OS group (P < 0.05). Consistent with this, the Bax and Caspase-3 levels in hippocampal neurons of rats in the OS group, GABA+OS+Picrotoxin group and GABA+OS+CGP54626 group were significantly higher than those in the control group and GABA group (P <0.05), which indicated that GABA alleviated the damage of hippocampal neurons under oxidative stress, and the addition of GABA receptor inhibitors blocked the anti-stress damage effect of GABA. 【Conclusion】GABA reduced the level of oxidative stress in the hippocampus of piglets. The anti-stress mechanism of GABA could be related to the decrease of the expression of apoptotic protein gene, while GABAA and GABAB receptors mediated this process.


]]> <![CDATA[Effects of Sowing Date on Yield of double cropping rice and Utilization Efficiency of Light and Heat Energy in Hunan Province]]> By comparing the effects of different sowing dates on yield of double cropping rice and utilization efficiency of litht and heart energy, and analyzing the sensitivity of different varieties to sowing date and light and heat resource efficiency, the best sowing date was investigated , which was conducive to double-cropping rice yield and resource utilization efficiency in Hunan Province.【Method】Using the main double-cropping rice varieties approved in Hunan Province, the main double-cropping rice producing area, as the test materials, three sowing dates for early and late rice were set up for field experiments from 2018 to 2019. The rice growth period, yield and yield components as well as meteorological data were analyzed to compare the yield and the utilization efficiency of light and heat resources of each variety under different sowing dates.【Result】With the delay of the sowing date, the early and late rice shortened the growth period by shortening the days of the sowing-ear start stage, while the yield of early rice showed an increasing trend. Late-maturing rice responded faster to late sowing than middle-maturing late rice; in 2018, with the delay of sowing, the thermal energy utilization rate of early rice decreased by 2.73% and 4.45%, and the light energy utilization rate decreased by 1.28% and -1.77%, respectively. The utilization rate decreased by -2.64% and 8.15%, respectively, and the utilization rate of light energy decreased by -2.14% and 13.25%, respectively; In 2019, with the delay of the sowing date, the utilization rate of heat energy of early rice increased by 0.36% and 10.36%, respectively, and the utilization rate of light and heat increased respectively. 1.53% and 12.52%, the thermal energy utilization rate of late rice decreased by -0.72% and 6.09%, respectively, and the light energy utilization rate decreased by 0.58% and 6.21%, respectively.【Conclusion】The sowing date had a significant impact on the utilization efficiency of light and heat resources of double-cropping rice. It was appropriate to delay the sowing date of early rice and advance the sowing date of late rice to improve the efficiency of light and heat resources. The comprehensive efficiency of the combination of sowing date was higher, and the combination of late-maturing early rice and medium-maturing late rice combination had higher comprehensive efficiency.


]]> <![CDATA[Effects of Seedlings Enriched with Zinc on Cadmium Accumulations and Related Transporter Genes Expressions in Different Rice Cultivars]]> 】Rice seedlings enriched with zinc (Zn) is a new method to antagonize cadmium (Cd) within rice, studying the various effects and underlying mechanisms among different rice cultivars is useful to provide a basis for the application of this method. 【Method】Hydroponic and pot experiments were conducted to test the effects of the Zn enrichment in four cultivars including the Wuyunjing21, Zhejingyou1578, Huanghuazhan, and Huiliangyousimiao. Dynamics of Zn accumulation in different cultivars, and variations of Cd uptake and transport in rice tissues were investigated. Furthermore, the expressions of the Cd-related transporter genes of the root were analyzed to explore the underlying mechanisms responsible for the various effects in different cultivars. 【Result】Results showed that the Zn cultivation didn’t affect the growth of all rice seedlings. Zn accumulations varied obviously among different cultivars, the Zhejingyou1578 had the highest Zn level (230 μg Zn per plant), followed by the Wuyunjing21 (124 μg Zn per plant), the Huanghuazhan and Huiliangyousimiao had the low levels (85.1-95.0 μg Zn per plant). Zn enrichment greatly influenced the expression of Cd-related transporters in the Zhejingyou1578, the OsZIP7 was down-regulated by 48.7% and OsZIP1 was up-regulated by 81.3%. The expressions of the OsIRT1 and OsZIP7 in the Wuyunjing21 were also down-regulated by 35.9% and 35.0%, respectively, and the OsZIP1 was up-regulated by 31.1%. However, the Cd-related transporters in the Huanghuazhan and Huiliangyousimiao were insensitive to Zn enrichment. As a result, Zn enrichment significantly reduced Cd concentrations in the root and shoot by 26.7% and 36.7% of the Wuyunjing21, and 32.0% and 40.0% of the Zhejingyou1578 with an 12.0% inhibition on the Cd transport, respectively. Furthermore, brown rice Cd were reduced by 37.5%, 36.7% and 25.3% in the Wuyunjing21, Zhejingyou1578, and Huanghuazhan, respectively, while no difference occurred in the Huiliangyousimiao, revealing various effects on reducing Cd among different cultivars induced by the Zn enrichment. Correlation analysis showed that the brown rice Cd was negatively correlated with the shoot Cd which was negatively correlated with the root and shoot Zn, revealing a significant antagonism between Zn and Cd within rice. However, the root and shoot Zn were negatively correlated with the OsZIP7 and OsIRT1 and positively correlated with the OsZIP1 expression, indicating that the Zn enrichment within seedlings influenced the brown rice Cd mainly through regulating the expressions of the OsZIP1, OsZIP7 and OsIRT1. 【Conclusion】The regulations on Cd-related transporters through Zn enrichment were varied among different cultivars, and the Zhejingyou1578 and Wuyunjing21 were more sensitive, so that the reductions of brown rice Cd were higher than other cultivars.


]]> <![CDATA[Effect of Valproic Acid on Reprogramming of Bactrian Camel Fibroblasts]]> Objective】 In order to improve the efficiency of the reprogramming process of bactrian camel fibroblasts and reduce the risk of tumorigenesis caused by the introduction of proto-oncogenes. In this experiment, valproic acid (VPA) was added to the fibroblast reprogramming process to explore the effect of small molecules on the reprogramming of Bactrian camel fibroblasts. 【Methods】 In view of this, we used March-aged Bactrian camel fetal fibroblasts, combined with classic induction combination OSKM (Oct4, Sox2, Klf4, and c-Myc) and EGFP five retrovirus reprogramming of bactrian camel fibroblasts (OSKM group), and collected the cells by adding VPA treatment for 7 days after the second viral infection (OSKM+VPA group). Endogenous and exogenous genes were examined using PCR to confirm the modification effect of retrovirus on Bactrian camel fibroblasts. Eight genes were randomly selected from those more significantly affected by VPA according to RNA-seq data to check whether their trends before and after VPA addition were consistent with the trends of RNA-seq data to verify the accuracy of RNA-seq data. The transcriptome sample genes were classified by GO analysis and significant enrichment pathways for target genes were clarified using KEGG pathway enrichment analysis and hypergeometric validation analysis. Total RNA was extracted from the collected cells and combined with RNA-seq and Real time-quantitative interpretation（RT-qPCR） techniques to detect the effect of VPA on the reprogramming of Bactrian camel fibroblasts. 【Results】 It was detected using PCR that the expression of endogenous and exogenous genes in different groups. The results showed that nSox2, Sox2, Oct4, Klf4 and c-Myc genes were expressed in both OSKM and OSKM+VPA groups, and the expression in OSKM+VPA group was higher than that in OSKM group, while they were not expressed in BCEFs group. Eight genes were randomly selected for testing, and the results showed that: three genes TP53, CCNB1 and CCD20, which are related to cell cycle signalling pathway, were down-regulated in expression after the addition of VPA; S100A4, CKS2, VIM and MMP9 genes, which are related to the phenotypic characteristics of cancer, were down-regulated in expression; VEGFC gene expression was up-regulated in PI3k-Akt signalling pathway. This expression trend is consistent with the trend of the histological data. The results showed that the expression of proliferation genes Mki67 and PCNA were down-regulated, while the expression of apoptosis gene CASP7 was up-regulated after the addition of VPA. KEGG and hypergeometric validation analyses of the transcriptome data were performed, and 959 differentially expressed genes were screened according to the analysis results, which were enriched in 276 signalling pathways, including eight signalling pathways with Q values less than 0.05: steroid biosynthesis, cell cycle, PPAR signalling pathway, progesterone-mediated oocyte maturation, fatty acid metabolism, ECM-receptor interactions, cell adhesion molecules and cholesterol metabolism. The 26 differentially expressed genes related to cell cycle, fatty acid metabolism, cell adhesion molecule and cholesterol metabolism were screened and four of them were randomly selected for testing, showing that VPA upregulated the expression of L1CAM, CNTN1 and NFASC genes in the Bactrian camel fibroblast adhesion molecule signalling pathway and enhanced intercellular interactions. It was also upregulated that the expression of CD36 gene in the fatty acid signaling pathway. 【Conclusion】 The results showed that the VPA to cell block before the split phase, to reduce risk differentiation during the process of reprogramming. Meanwhile, VPA affected several signaling pathways in the reprogramming process of Bactrian camel fibroblasts, and regulated the expression trend of related genes in the signaling pathways, which effectively improved the reprogramming efficiency of the cells and played an important role in the reprogramming of Bactrian camel fibroblasts.


]]> <![CDATA[Development and Application of a Universal Ielisa Antibody Assay for Abortion- Causing<i> Salmonella</i> in Equidae #br#]]> 】The aim for this study was to identify the predominant antigen of Salmonella and to develop a sensitive, specific and universal iELISA assay for the rapid and accurate detection of Salmonella antibodies in equidae.【Method】For the purpose of screening out dominant antigens for Salmonella abortus equi, immunoprecipitation (pull down) tests were performed using Salmonella abortus equi positive/negative sera with whole bacterium antigens of Salmonella abortus equi.Then, amino acid sequence alignment of the dominant antigen were compared with salmonella typhimurium, salmonella dublin and Salmonella enteritidis to verify it is conservative.Three pairs of specific primers were designed and synthesized according to the nucleotide  sequence of the full ompA gene published in GenBank. Three different lengths of ompA gene was amplified by PCR and then cloned into pET28a vector and transformed Escherichia coli Rosetta (DE3) competent cell. The expressed products were analyzed by SDS-PAGE electrophoresis and Western-blot test after induced by IPTG. The reactivity of the purified protein was verified using S.abortus equi, salmonella typhimurium (s.typhi), salmonella dublin (s.dublin) and S.enteritidis serums and one negative serum by Western blot. An indirect ELISA method for the diagnosis of equine abortion salmonellosis was developed by optimizing the amount of coating antigen, serum and secondary antibody concentrations using the purified ompA3 protein as the coating antigen, and evaluating the specificity and sensitivity of the iELISA, and finally applying the iELISA to detection clinical samples.【Result】In this study, the ompA dominant antigen of S.abortus equi was screened. S.abortus equi ompA is conservative and shows 99.4-100% identical with salmonella typhimurium, salmonella dublin and S.enteritidis strains at the amino acid level.Three target genes were successfully obtained by PCR amplification.Three recombinant plasmids pET28a-ompA1, pET28a-ompA2 and pET28a -ompA3 were successfully constructed. The expressed products were analyzed by SDS-PAGE electrophoresis and Western-blot test after induced by addition of IPTG to a final concentration of 0.6 mM for 5 h at 24℃. We obtained recombinant ompA1 and ompA2 in a inclusion and soluble recombinant ompA3 proteins. The soluble recombinant ompA3 were identified by Western blot, which can have a specific reaction with four salmonella positive serums, So, the ompA3 was can considered as a potential target candidate for serological detection of Salmonella. An iELISA method was developed in a maximum P/N ratio,using the coating antigen at a concentration of 1 μg/mL, a serum dilution of 1:200 and secondary antibody was 1:10000. The cutoff value is 0.143, an OD450 value over 0.143 was considered as positive. The specificity test showed that the coated antigen did not cross-react with the positive serum of common equine infectious diseases. The iELISA provides better sensitivity by detecting antibodies in intravenously infected horses, as the iELISA can continue to monitor antibody positivity up to 116 days, 47 days longer than microagglutination test(69 days). The established iELISA method was used to detect antibodies in 180 serum samples from 8 different farms. The average positive rate of iELISA antibody was 63.3%, which was 53.9% higher than that of micro agglutination test.【Conclusion】The soluble ompA3 protein was successfully expressed, and a universal indirect ELISA antibody method was established for the diagnosis of equine abortus salmonellosis. The method enables detection of antibodies to Salmonella abortus equi in clinical samples.The method has good specificity and sensitivity and could be a promising candidate tools for use in the monitoring of the equine abortus salmonellosis epidemic.


]]> <![CDATA[Development Strategies and Application Prospects of African Swine Fever Vaccines]]> <![CDATA[Investigation and Analysis of Nucleic Acid Detection Results of Vain Viruses in Large-scale Goose Farms]]> Objective】The author's research group has long investigated the nucleic acid detection rate of common viral diseases in scaled goose farms in various provinces and cities in China, and found that many large-scaled goose farms in China can detect multiple viral nucleic acids at the same time and this phenomenon is very common. In view of the lack of relevant data on the simultaneous detection of multiple viral diseases in large-scale goose farms in China. The purpose of this paper is to understand and analyze the simultaneous detection of nucleic acids of multiple viral diseases in large-scaled goose farms and provide theoretical guidance and scientific basis for the prevention and control of viral diseases in scaled goose farms. 【Method】From May 2021 to October 2021, 737 diseased materials were collected from 47 scaled goose farms in Shandong, Heilongjiang, Sichuan, Jilin, Guangxi, Henan, Anhui, Liaoning, Hebei, Guizhou, Hunan and Inner Mongolia. These samples were detected for Muscovy duck reovirus (MDRV), Duck reovirus (DRV), Goose astroviruses (GAstV), Fowl adenovirus (FAdV), Reticuloendotheliosis virus (REV), Newcastle disease (NDV), Goose parvovirus (GPV), Goose circovirus (GoCV), Goose hemorrhagic polyomavirus (GHPV), Tembusu virus (TMUV) and H9 subtype avian influenza virus (H9-AIV) by ordinary PCR and RT-PCR. Liver, spleen, lung and kidney were dissected from each sample, and total RNA was extracted by Trizol method; A strand of cDNA was synthesized by reverse transcription with total RNA as the template, and then the complete cDNA was obtained by continuous amplification with cDNA as the template. Using these cDNA as template, the specific primers of Muscovy duck reovirus, Duck reovirus, Goose astrovirus, Fowl adenovirus, Reticuloendothelial virus, Newcastle disease virus, Goose parvovirus, Goose circovirus, Goose hemorrhagic polyomavirus, Tambusu virus and H9 subtype avian influenza virus were used to amplify the target fragment by ordinary PCR reaction. All amplified fragments were analyzed by agarose gel electrophoresis, and some positive samples were sequenced. The obtained sequencing results were compared with the corresponding virus gene sequences published on GenBank, and the phylogenetic tree was drawn by Neighbor-Joining (N-J) method in MEGA 6.0 software for analysis. 【Result】Muscovy duck reovirus, Duck reovirus, Goose astrovirus, Fowl adenovirus, Reticuloendothelial virus, Newcastle disease virus, Goose parvovirus, Goose circovirus, Goose hemorrhagic polyomavirus, Tambusu virus and H9 subtype avian influenza virus showed that the detection rate of GAstV was the highest, 58.21%; The detection rates of REV and NDV were the lowest, 1.36% and 1.50% respectively. A variety of viral nucleic acids can be detected simultaneously in geese to varying degrees, especially in two or three viral nucleic acids, accounting for 67.44% of the total samples. In the simultaneous detection rate of nucleic acids of the two viruses, GAstV and GoCV accounted for the largest proportion, which was 18.44%; MDRV, GAstV and GPV accounted for 36.28% of the simultaneous detection rates of the three virus nucleic acids. 【Conclusion】It is further confirmed that multiple viral nucleic acids can be detected simultaneously in large-scaled goose farms in China. It is speculated that this may be one of the important reasons for the complexity of viral diseases and the difficulty of prevention and control in large-scaled goose farms in China.


]]> <![CDATA[Effects of Intermittent Different Temperature on Feeding and Intestinal Development of Growing Layers]]> 】The objective of this study was to study the effects of ambient temperature on feeding and intestinal development of poultry, and to supplement the absent temperature parameters for laying hens rearing, and to provide a certain scientific basis for the correct feeding of laying hens.【Method】A total of 360 Issa brown laying hens aged 11 weeks were selected and divided into 5 treatment groups with 6 replicates per group and 12 hens per replicate. The experimental laying hens were transferred to 5 intelligent environmental control chicken houses for 1 week of pre-trial and 8 weeks of formal experiment, and 3 chickens per cage. The relative humidity in the chicken house was kept at 60%, and the light was kept for 8 h (9:00-17:00) every day during the prelay period. The temperature of the control group was kept unchanged at 22℃, and four treatment groups were carried



out in a manner of daily intermittent, that is, 24℃ or 26℃ or 28℃ or 30℃ at 10:00-18:00 every day, and changed to the base temperature 22℃ for the rest of the time, the heating and cooling time are within 1 h. The experiment lasted for 8 weeks. The experimental laying hens were free to eat and drink, the feed intake was counted weekly, and the samples were collected once every two weeks. Twelve hens in each group were randomly selected and weighed, and then killed by neck cutting. The weight of glandular stomach, the weight and length of duodenum, jejunum and ileum were weighed. Hypothalamus, glandular stomach and duodenum samples were frozen in liquid nitrogen and stored at -80℃. Feed intake was calculated in heat treatment period and non-heat treatment period for 3 days before the end of experiment.【Result】The results showed that compared with T22 group, the feed intake in T30 group was significantly decreased at 13-16 wk (P < 0.05); the feed intake in T24 group was significantly higher than that in T28 and T30 groups at 17-20 wk (P < 0.05) . During the heat treatment period, the feed intake of T30 group was significantly lower than that in T22 and T24 groups (P < 0.05). The feed intake of T30 group was significantly lower than that in T22, T24 and T26 groups during the non-heat treatment period (P < 0.05). The feed intake in the heat treatment period was significantly lower than that in the non-heat treatment period (P < 0.05), and the highest feed intake was maintained in T24 group and the lowest in T30 group. Compared with T22 group, the glandular gastric index was significantly increased at 16wk (P < 0.01). At 18wk, compared with T22 group, jejunum index in T30 group was significantly lower than that in other groups (P < 0.05). At 20wk, compared with T22 group, the glandular stomach index, jejunum index and ileum index in T24 group were significantly increased (P < 0.05), and jejunum index was significantly higher than that in T30 group (P < 0.05). Compared with T22 group, the expression of NPY (Neuropeptide Y) in hypothalamus of all treatment groups was significantly increased at 14wk (P < 0.05). The expression of AgRP (Agouti-related protein) in hypothalamus of T30 group was significantly decreased (P < 0.05), and the expression of CCK (Cholecystokinin) in duodenum of T30 group was significantly increased (P < 0.05). At 20wk, compared with T22 group, the expression of CART (amphetamine-regulated transcript) in hypothalamus of T24 group was significantly decreased (P < 0.05), and the expression of ghrelin in glandular stomach of T24 group was significantly decreased (P < 0.05).【Conclusion】These results indicate that ambient temperature at 24℃ during the growing period can promote the development of gastrointestinal tract, increase the expression of NPY in hypothalamus, and inhibit the expression of CART and ghrelin in hypothalamus, which is beneficial to the growth and development of laying hens. However, high temperature treatment at 30℃ can damage the intestinal tract of laying hens, inhibit the expression of hypothalamus feeding promoting factor AgRP, and promote the expression of duodenal feeding inhibiting factor CCK, thus inhibiting feeding intake and reducing feed intake of laying hens.

]]> <![CDATA[Screening of Wnt3a Gene SNPs and Its Association Analysis with Skin Feather Follicle Density Traits in Chicken]]> Objective】The Wnt signaling pathway plays an important role in the development of animal skin feather follicles. The results of previous studies indicated that the Wnt3a may be an important candidate gene that had effects on the chicken feather follicle density. In order to further verify the role of Wnt3a in the growth and development of skin feather follicle density, Wnt3a SNPs were screened and their association with feather follicle density will be analyzed in Jinling Hua chicken. It will provide a reference for“breeding by molecular writing” of slaughter-type broilers with beautiful carcasses.【Method】The SNPs of Wnt3a gene were screened by PCR amplification and direct sequencing, and the correlation between a single SNP marker and skin feather follicle density traits was analyzed. Haploview software was used to analyze the degree of linkage disequilibrium (LD) of these SNP loci, and the correlation between different haplotype combinations and feather follicle density traits was also analyzed. 【Results】A total of 14 SNP sites were found, and one SNP site (SNP1) was found in the second exon, which was a synonymous mutation. Four mutation sites (SNP2-SNP5) were found in the second intron, and 9 SNP sites (SNP6-SNP14) were found in the third intron. The chi-square test showed that one mutation site (SNP1) in the second exon and three mutation sites (SNP3-SNP5) in the second intron were all in the Hardy-Weinberg equilibrium (P >0.05), the 9 mutation sites (SNP6-SNP14) of the third intron deviated from Hardy-Weinberg equilibrium (P<0.05). The expected heterozygosity (He) of SNP1-SNP5 is less than 0.50, and the polymorphic information content (PIC) is less than 0.25. The genetic polymorphisms of these 5 SNP loci are low. The third intron had 9 mutation sites, PIC of SNP6, SNP7, SNP9 sites was less than 0.25, and the other 6 mutation sites 0.25<PIC<0.5, which were moderately polymorphic. Single-marker association analysis showed that the number of skin feather follicle with SNP2 locus of AG genotype in males and females was significantly higher than that of GG genotype (P＜0.05). The number of skin feather follicles with SNP8 locus of AA and GG genotypes in females was significantly higher than that of the AG genotype (P<0.05). The skin feather follicles density in the three genotypes in males was not significantly different. The linkage disequilibrium analysis of 14 SNPs showed that SNP6-SNP13 and SNP3-SNP5 had a strong linkage disequilibrium, respectively. SNP3, SNP4, and SNP5 produced three haplotype combinations after the combination of the two haplotypes linked by SNP3- SNP5. Association analysis found that the skin feather follicle density of the three haplotype combinations in males and females were not significantly different. After the combination of 5 main haplotypes at SNP6-SNP13 locus, males had 7 haplotype combinations, and the skin feather follicles density was not significant. Females had 8 haplotype combinations, of which H1H1 (AACCAATTTTAATTCC) had the highest skin feather follicles density. SNP2 and SNP8 are significantly correlated with skin feather follicle density, and the haplotype combination H1H1（AGAA） and H1H2 （AGAG）are the dominant haplotypes in hens.【Conclusion】Fourteen SNPs of Wnt3a were screened. Among them, individuals with different genotypes at rs2587721 G > A (SNP2) and rs2555967G>A (SNP8) locus have significant differences in feather follicle density. Eight SNPs (SNP6-SNP13) loci are in strong linkage disequilibrium, and the combination of H1H1 had the highest feather follicles density in females. The haplotype combination of SNP2 and SNP8 of Wnt3a H1H (AGAA), H1H2 (AGAG) and SNP6-SNP13 linked to produce the H1H1 （AACCAATTTTAATTCC）haplotype combination are significantly correlated with feather follicle density in females, which can provide important genetic information for“breeding by molecular writing”on chicken skin feather follicle density. 


]]> <![CDATA[Effect of Circadian Rhythm on Rumen Fermentation and Nutrient Digestion of Mutton Sheep]]> 【Method】Forty-five healthy Hu sheep with body weight of (21.57 ± 0.77kg weight)  were randomly divided into 3 groups, with 15 sheep in each group. Each treatment group used the same concentrate supplement and coarse feed, and the concentrate coarse ratio of the basic diet was 56:44. The three treatments were respectively set as follows: day treatment group, that was, 70% of the total daily concentrate + 30% of the total daily coarse feed in the morning, which was recorded as DH; In the evening treatment group, 30% of the daily total concentrate + 70% of the daily total coarse feed were fed in the morning, which was recorded as DL; The control group, i.e. 50% of the daily total concentrate + 50% of the daily total crude feed in the morning and evening, was recorded as CON. After feeding for two months, the digestion and metabolism test was carried out.  Total fecal collection and urine were used to determine nutrient apparent digestibility and metabolic rate.  After the feeding experiment, rumen fluid samples were collected from oral cavity 2 hbefore morning feeding and 2 h before evening feeding, respectively, for the determination of related indexes.  【Results】 ① The daily gain of DH was 215.00g, the food intake was lower than that of DL and CON, and the feed conversion ratio was the best, which was 5.35, which was 11.19% and 16.04% better than the other two groups, respectively. ② Under different feeding modes, the digestibility of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) of sheep in DH group were higher than those in CON and DL groups. Compared with DL group, DM digestibility increased by 21.42%, CP increased by 22.29%, NDF increased by 9.85% and ADF increased by 28.69%. ③ The biological value of nitrogen in DH group was 20.31% higher than that of CON and 67.41% higher than that of DL (P>0.05). There was no significant difference in the intake of digestible nitrogen among all groups, and the total nitrogen excretion in DL group was significantly higher than that in DH group (P<0.05). The nitrogen deposition, nitrogen utilization and biological value in DH group were significantly higher than those in DL group (P<0.05) and CON group (P>0.05). ④ There were no significant differences in rumen microbial protein (MCP), acetic acid and total volatile fatty acid (TVFAs) among groups with different treatments (P>0.05), rumen pH, the ratio of acetic to propionic acid and butyric acid in DH group were significantly lower than those in DL group (P<0.05). With the alternation of day and night, rumen pH, NH3-N, acetic acid, propionic acid, total volatile fatty acid and the ratio of acetic to propionic acid were significantly changed (P<0.05), and related parameters were higher in day than in night.【Conclusion】Growth performance and nutrient digestibility of sheep could be improved by changing the ration of concentrate to forage in the early and late days under the same nutrient content in the diet, and feeding high concentrate ratio in the morning and low concentrate ratio in the afternoon. Rumen fermentation was affected by day and night, and feeding high concentrate diet in day promoted the contents of TVFAs, NH3-N and MCP in rumen. In a word, from the results of this experiment, the effect was better to increase the proportion of concentrate in the morning. It is more consistent with the rhythm of digestion and absorption of the animal body.

]]> <![CDATA[Evaluating the Application of Single-step Genomic Selection in Pig Populations]]> Background】The contribution of genetic breeding is highest in improving the efficiency of animal production. Through breeding, animal husbandry enterprises can improve production efficiency and obtain maximum economic benefits. Genome selection has been widely used in plant and animal breeding. Genomic selection can estimate breeding values (EBV) by using high density markers covering the whole genome. Compared with pedigree information, the average relationship between individuals obtained by using these markers is more accurate, so that breeding values can be more accurately estimated and individuals can be selected. In practical breeding program, all individuals are not genotyped, especially for pigs, whose economic values are not high enough, hence the application of genomic selection is limited in pig breeding. The single-step genomic best linear unbiased prediction (ssGBLUP） can utilize both pedigree and genotypes information, allowing part of individuals are genotyped, thus greatly reducing genotyping costs while maintaining high prediction accuracy. At present, many studies have shown that the use of genomic selection in pig breeding can improve the accuracy of prediction, but in actual breeding, breeding cost is also an important issue in livestock enterprises to consider. Therefore, how to implement breeding program economically and effectively is of great research value.【Objective】The study on the effect of one-step genome selection on the population evaluation of Duroc provided the basis for genome selection breeding program.【Methods】In this study, three important economic traits of duroc pig born from 2009 to 2018 in a pig farm in Fujian province were studied. We compared the accuracy of BLUP, GBLUP, and ssGBLUP in calculating the estimated breeding value on reproductive and growth traits of Duroc pigs. We explored the impacts of genotyped individuals with different proportions in the reference population on the ssGBLUP prediction abilities. We also studied the influence of different chip density on GBLUP prediction abilities. 【Result】The results showed as follows: 1) The heritability of the age at 100kg, backfat and eye muscle area was 0.257, 0.250 and 0.399, respectively; 2) Compared with BLUP, the accuracy of ssGBLUP was improved by 14.7%~51.1%; Compared with GBLUP, the accuracy increased by 13.4%~45.7%; 3) When 10%~30% of individuals was genotyped, the prediction accuracy of ssGBLUP can exceed that of BLUP; The prediction accuracy reaches a plateau when 40-60% of individuals genotyped. 【Conclusion】Based on the above results, it was concluded that: 1) Compared with BLUP, ssGBLUP can improve the accuracy and reliability of EBV for each trait; Compared with the GBLUP, ssGBLUP was slightly lower than the GBLUP with only pedigree information of those ungenotyped, but ssGBLUP performed better than the GBLUP method after the addition of phenotypes of the ungenotyped individuals. 2) As the proportion of genotyped individuals in the reference population increases, no matter which selection method is used to determine genotyped individuals (random selection and selection the key individuals), the prediction ability of ssGBLUP is gradually improved. The results showed that the ssGBLUP can improve the prediction ability of individual breeding value even if only a proportion of individuals were genotyped when the breeding budget was limited.


]]> <![CDATA[Identification of 60 Citrus Accessions Using Target SSR-seq Technology]]> 】Bud sports mutation is a DNA mutation occured in somatic meristem, it often display visible morphological and other charactistics changes different from its mother plants in branches, leaves, flowers and fruits. However, discrimating bud sports mutation from the epigenetic variation caused by environmental conditions and cultivation measures etc. external factors was still mostly depended on the morlecular fingerprint detection. 【Objective】This study objective was to identifiy citrus bud sports mutant through Target-SSR sequencing thechology.【Method】Firsly the genome of clementine mandarin (Citrus reticulata Blanco) and satsuma (Citrus unshiu Macf.), as well as GSS and EST sequences of satsuma were used to scan SSRs loci with GMATA, the highly polymorphic SSRs loci were screened out to design primers, multiplex PCR with optimized primers were amplified on 60 citrus bud sports mutants to construct high-thoughout sequencing library, the ampification products were then sequenced on illumina Minseq platform, the clean sequencing short reads were mapped to reference target sequences to find differentiated SSRs loci presented in citrus bud sports mutants.【Result】 A total of 77 pairs of SSR primers were designed from highly polymorphic SSRs loci. The primers pairs combination were optimized and 18 multiplex PCR amplification products were sequenced. Target SSR-seq analysis showed that the genotyping data of SSRs could divided 60 citrus accessions into two groups correspongding to sweet orange and mandarin, and mandarin group could be further subdivided into different citrus cultivar such as Orah, ponkan etc. 11 SSR loci containing mostly ATT motif were found in 7 Tarroco blood orange mutants, 8 SSR loci containing mostly TAA motif were found in 2 ‘Wu Yue Hong’ mutants and 5 navel orange, 16 SSR loci containg mostly GA motif were found in 9 Bing Tang Cheng mutants, 9 SSR loci containg mostly AAT motif were found in 2 Sha Tang Ju mutants, and 15 SSR loci with mostly AAT motif were found in 4 satsuma mutants. This study showed that Target-SSR sequecning technology provided an excellent resolving approach to discriminate citrus bud mutations.【Conclusion】In this study, an effictive method for citrus bud mutant identification using Target SSR-seq technology were established, 60 citrus germplasm accessions could be discriminated. The precision and reliability of SSR genotyping information could be utilizaed in citrus germplasm resources managemant and variety intellectual property protection.



]]> <![CDATA[Physiological Metabolic Role of Nanocomposite Packaged Agaricus bisporus During Postharvest Cold Storage Analyzed by TMT-Based Quantitative Proteomics]]> 】Agaricus bisporus is prone to quality deterioration such as umbrella opening, water loss, and browning after harvest, which seriously affects the storage quality and commercial value. Our previous research has confirmed that nanocomposite packaging material (Nano-PM) could effectively delay the postharvest quality deterioration of A. bisporus, but the preservation mechanism is still unclear. 【Objective】In this study, the differentially expressed proteins of A. bisporus in Nano-PM and polyethylene packaging material (Normal-PM) during storage were analyzed by Tandem Mass Tag (TMT) quantitative proteomics technology. The preservation mechanism of Nano-PM on A. bisporus was further explored. 【Method】A. bisporus was taken as the research object. The Nano-PM was used for the preservation of A. bisporus, and the Normal-PM was used as the control. Protein extraction and trypsin hydrolysis were performed on A. bisporus during storage. Differentially expressed proteins were screened by TMT labeling and liquid chromatography-tandem mass spectrometry detection. Combined with bioinformatics analysis, the main metabolic pathways involved in differential proteins were studied. Quantitative real-time polymerase chain reaction (qPCR) technology was used to determine the gene expression levels of differential proteins. 【Result】The Nano-PM effectively maintained the appearance quality of A. bisporus and delayed the increase of cell membrane permeability. The number of differential proteins in two groups increased during storage. In the middle (6 d) and late (10 d) stages of storage, the numbers of differential proteins were 62 and 148, respectively. Among them, 22 differential proteins were common. Combined with bioinformatics analysis, these differential proteins were mainly related to pathways such as energy metabolism and lipid metabolism. The lipid metabolism pathway was mainly analyzed, and the results showed that the Nano-PM had a regulatory effect on the membrane lipid metabolism of A. bisporus. Compared with the Normal-PM, the protein expression of Fatty acid synthase, Phosphorylcholine cytidylyltransferase, and Phosphatidic acid phosphatase in the Nano-PM were up-regulated. While the protein expression of key enzymes in membrane lipid degradation such as Phospholipase D and Lipase were down-regulated. At the gene level, the expression of genes encoding these proteins were consistent with the proteomics results. 【Conclusion】The differential proteins of different packaged A. bisporus during storage could be screened and analyzed by TMT-based quantitative proteomics technology. Nano-PM regulated the membrane lipid metabolism of A. bisporus, inhibited the expression of membrane lipid degradation-related enzymes, which effectively delayed the increase in cell membrane permeability of A. bisporus, maintained the structure and function of the cell membrane, and delayed the quality deterioration of A. bisporus during storage.


]]> <![CDATA[Cloning and Interaction Protein Screening of RHF2A Gene from ‘Xiangshui’ Lemon]]> 【Objective】‘Xiangshui’lemon (Citrus limon (L.) Burm. F.) was used to study the expression of two RHF2A genes, and to screen and verify their interaction proteins by yeast two hybrid technology and BiFC, and lay a foundation for further studying the molecular mechanism of RHF2A in the process of lemon selfincompatibility. 【Method】 Two E3 ubiquitin ligase RHF2A(RING-H2 Zinc Finger2A) genes RHF2A-1 and RHF2A-2 of ‘Xiangshui’ lemon were screened from the transcriptome and ubiquitin modification group, and their full-length sequences were cloned. The sequence and protein structure of two RHF2A genes were analyzed by bioinformatics to predict the cis acting elements of their promoters. 35S-RHF2A-GFP fusion protein expression vector was constructed for subcellular localization analysis. The temporal and spatial expression patterns of two RHF2A were analyzed by real-time fluorescence quantitative PCR. The yeast two hybrid bait vector was constructed to screen the interaction proreins from the lemon yeast library. The BiFC vector was constructed to verify the interaction of the target protein in onion living cells.【Result】The RHF2A-1 and RHF2A-2 genes were obtained from ‘Xiangshui’ lemon, and the total length of ORF was 1161 and 1134 bp respectively. NCBI domain prediction found that it had a Ring/U-box domain. Promoter analysis showed that there are POLLEN1LELAT52 and GTGANTG10 related to pollen specific expression elements. Tissue expression analysis showed that RHF2A-1 gene was specifically expressed in pollen and RHF2A-2 was specifically expressed in leaves; the results of temporal and spatial expression analysis showed that the expressed of RHF2A-1 in self stigma tended to increase from the first day and reached the peak on the third day, which was more than 5 times that of hybrid stigma. Subcellular localization showed that RHF2A-1and RHF2A-2 were localized in the nucleus. The interaction protein predicted by Uniprot website shows that RHF2A can interact with KRP6, AT3G57370, UBA1, FBL17 and SK11proteins, and that RHF2A gene is involved in biological processes such as self incompatibility ubiquitination reaction pathway, gametophyte development regulation and pollen growth and development. 72 clones were screened by yeast two hybrid technology. After sequencing and blast comparison, repetitive clones were excluded. Finally, 20 candidate interaction proteins such as ABCF3 were obtained. Through one-to-one interaction verification and BiFC, it was determined that there is an interaction relationship between RHF2A-1 and ABCF3-2. 【Conclusion】 The temporal and spatial expression of RHF2A-1 gene was consistent with the germination of pollen on pistil in the process of self incompatibility; The interaction candidate proteins directly affecting pollen growth and development during the pollination were screened, which preliminarily proved that RHF2A-1 gene played an important role in the process of self incompatibility.

]]> <![CDATA[Transcriptome and Metabolome Integrated Analysis of the Epistatic Genetics Effects on Eggplant Peel Color]]> Objective】Peel color is closely related to the appearance and value of eggplant. Anthocyanin is one of the natural pigments that determines an eggplant’s peel color. Through the comparison of gene expression and metabolites as well as the analysis on the mechanism of epistatic gene interaction and regulation of anthocyanin synthesis in eggplant peel, this paper provides a theoretical basis for eggplant breeding with different peel colors.【Method】White-peel female parent 19141 with mutation at the structural gene ANS of anthocyanin biosynthesis pathway, white-peel male parent 19147 with mutation at regulatory gene MYB1 of anthocyanin biosynthesis pathway, and their F1 hybrid E3316 with reddish-purple-peel were used as test materials, while transcriptome sequencing and wide-targeted metabolome analysis were performed on peels of commercial eggplant.【Result】Transcriptome sequencing analysis showed that: 19141_ vs _ 19147 had the most differentially expressed genes (DEGs), followed by E3316_ vs _ 19141. The two comparison groups both had the significant enrichment of DEGs in the flavonoid pathway. The DEGs of E3316_ vs_ 19147 were the least and were not enriched in the flavonoid pathway. A total of 218 metabolites were detected by wide-targeted metabolome analysis. A total of 113 differential accumulated metabolites (DAMs) were detected in E3316_ vs _ 19141, and totally 98 DAMs were detected in E3316_ vs_ 19147. Combined analysis of transcriptome and metabolome found that the relative expression levels of key structural genes CHS, CHI, F3H, DFR and ANS, key regulatory genes MYB1, AN1 and AN11, modifier genes 3GT, 5GT, AT and OMT, and transporter gene AN9 (GST) involving anthocyanin biosynthesis pathway had the relation of 19141 > E3316 > 19147. The contents of anthocyanin metabolite cyanidin (CAS: 528-58-5) and cyanin (CAS: 20905-74-2) related to peel coloration had the relation of E3316 > 19147 > 19141. The combined analysis of transcriptome and metabolome both showed that the difference of E3316_ vs _ 19141 was bigger than E3316_ vs_ 19147. Under the regulation of epistatic genes, F3'H and F3'5'H genes were expressed simultaneously in eggplant peel, but the expression level of F3'H was much higher than that of F3'5'H. The anthocyanin content of E3316 was higher than that of its parents, and the chlorogenic acid content was lower than that of its parents. 【Conclusion】Under the interaction of epistatic genes that control the peel color, the locus (type) and mutation mode of mutant gene in parent determine the trend of gene expression in the whole anthocyanin metabolism pathway and the inhibition mode of peel pigmentation. If the mutated gene is a structural gene of the anthocyanin biosynthesis pathway, the gene expression of the whole pathway will not be affected, but the loss of function in key enzymes causes interruption of pathway, and results in the white peel of the parent. If the mutated gene is an MYB transcription factor gene, which almost downregulates the expression of all genes in the anthocyanin biosynthesis pathway, and anthocyanin transport may be blocked, resulting in white peel of the parent. The reddish-purple-peel F1 hybrid of two white-peel parents is the result of the function complementation of two mutated gene involved in anthocyanin biosynthesis pathway. The highly expressed F3'H was the main cause for synthesis of cyanidin, and the relationship between anthocyanin and chlorogenic acid biosynthesis was competitive in peels.


]]> <![CDATA[Transcriptome Analysis During Flower Bud Differentiation of ‘Red Globe’ Grape]]> 】‘Red Globe’ grape is an important fruit tree species of China. Flower bud differentiation directly affects the quality and quantity of this grape. Its developmental stages S1 (undifferentiated), S2 (flower anlagen development), S3 (formation of the main cob of inflorescence), and S4 (formation of the second cob of inflorescence) during flower bud differentiation under natural growth conditions were compared and analyzed in this study. Evaluating the mechanism of flower bud differentiation of this grape variant and mining the essential genes can provide a theoretical basis for understanding the flower bud differentiation of this grape species. 【Method】Morphological observation, phytohormone determination, and transcriptome sequencing analysis were performed on the buds of four developmental stages during flower bud differentiation of the Red Globe grape. 【Result】A total of 13 729 differentially expressed genes were determined during the flower bud differentiation process of the Red Globe grape, which included 4 158, 2 050, 3 425, and 7 652 genes in S1–S2, S2–S3, S3–S4, and S1–S4, respectively. In the enrichment-regulation network of the S1–S4 differential genes, differential genes were found to be enriched in the hormone-mediated signaling pathways, abscisic acid metabolism, acid chemical reactions, plant cell wall tissues, or biogenesis. Several genes related to auxin, gibberellin, and abscisic acid were detected in the hormone-mediated signaling pathway. The results revealed that the content of auxin was the highest in S2 and the lowest in S3 and S4. Gibberellin content decreased continuously during flower bud differentiation, 80% of that at S4 in S1; abscisic acid content was higher in S1 and S4 and lowest in S2. In addition, the S1–S4 differential genes belonged to the transcription factor families (MYB, ERF, bHLH, and MADS-box), indicating that these family genes were involved in the flower bud differentiation of the Red Globe grape. Further analysis of the 13 differentially expressed MADS-box genes revealed upregulated expressions of MADS8, AGL65, AGL15, AGL12, and MADS2 during flower bud differentiation. In contrast, the expressions of AGL30, LeMADS, FBP24, AGL14, and MADS3 were downregulated. These MADS-box genes were verified via quantitative reverse transcription polymerase chain reaction, and the expression trend was found to be consistent with the corresponding transcriptome. 【Conclusion】Flower bud differentiation of the Red Globe grape is a complex biological process. The plant hormone-mediated signaling pathways and the MADS-box family genes play essential roles in flower bud differentiation. These results provide information about transcription factors, genes, and hormones to help understand this complex developmental process and provide a theoretical basis for establishing a comprehensive model for flower bud differentiation in the Red Globe grape.


]]> <![CDATA[Characterization of Chilled Mutton by ATP From Different Sources]]> 】To explore a new method for predicting the freshness of chilled mutton, the changes of adenosine triphosphate (ATP in meat, microbial ATP and ATP of meat surface) from different sources during storage were systematically studied, then the ATP that could characterize the change of chilled mutton was screened, and finally the prediction models for the total viable counts and volatile base nitrogen were established. 【Methods】The longissimus dorsi muscle of Small Tailed Han sheep was stored in air sealed packaging at 0℃ for 0，1，3，5，7，9，11，13，15，17 and 21 days, respectively. The freshness indexes (pH, color, volatile base nitrogen, total viable counts) and ATP from three sources (ATP in meat, microbial ATP, and ATP of meat surface) of chilled mutton were analyzed during storage. The changes of ATP from different sources were evaluated, and the predictive models of freshness indicators were built. The freshness index of total viable counts and volatile base nitrogen in chilled mutton showed an upward trend during storage, and both exceeded the national standard limit after 17 days; the ATP in meat showed a decreasing trend, while the microbial ATP and the ATP of meat surface were increased, which was consistent with the change trend of the freshness index; The correlation coefficients (R) between ATP in meat, microbial ATP, ATP of meat surface and total viable counts, total volatile base nitrogen were-0.399, 0.910, 0.943 and -0.357, 0.725, 0.907 respectively. The optimal model for predicting the total viable counts in chilled mutton by ATP of meat surface was Boltzmann, which the formula was TVC（log cfu/g）=7.649-4.069/(1+exp(x-5.807)/0.632)), (R2 =0.903, P<0.001), and the optimal model for predicting total volatile base nitrogen in chilled mutton by ATP of meat surface was Expedc1, which the formula was TVB-N（mg/100g）=2.493*exp(x/3.745)+3.057 (R2=0.888, P<0.001). 【Conclusion】The results showed that the ATP of meat surface of chilled mutton had the significant positive correlations with the total viable counts and volatile basic nitrogen, and then confirmed that the ATP of meat surface could be used as an indicator to characterize the freshness of chilled mutton. The optimal prediction model of the total viable counts and volatile base nitrogen could provide a new idea for rapid detection of chilled mutton freshness.

]]> <![CDATA[Screening and Functional analysis in heat-tolerance of the upstream transcription factors of pepper CaHsfA2]]> Background】 Pepper is widely cultivated as a vegetable around the world. With the increasing frequency of extreme high temperature weather in recent years, heat stress has become one of the main environmental factors affecting pepper productivity, due to its feature of warm-prone but heat-sensitive. Therefore, it is very important for pepper production to clarify its mechanisms supporting heat-tolerance and then develop pepper varieties with heat tolerance. 【Objective】 Since the heat shock transcription factor HsfA2 plays important roles in plant heat tolerance, the upstream transcription factor of pepper CaHsfA2 was screened and functionally analyzed in heat-tolerance in this study, in order to provide theoretical basis for further understanding the mechanisms of heat tolerance of pepper.【Method】The 955bp promoter sequence upstream of start codon of CaHsfA2 was used as the bait, the yeast one-hybrid (Y1H) technology was applied to screen the upstream transcription factors of CaHsfA2, and their interaction were checked by Y1H point-to-point hybridization, dual-luciferase reporter system (Dual-Luciferase), and LUC assay (LCA). For the candidate upstream transcription factors of CaHsfA2, its dynamic expression under heat stress in pepper heat-tolerant line R9 were analyzed by qRT-PCR technology; its subcellular localization were fulfilled through the transient gene expression technology, and its functional analysis in heat tolerance were performed using the virus-induced gene silencing technology (VIGS). 【Results】 CaBES1 was identified as the candidate upstream transcription factor of CaHsfA2, and their interaction was confirmed. By the analysis of Dual-Luciferase system and CaHsfA2 expression in CaBES1-silenced pepper plants, it is suggested that CaBES1 negatively regulates the transcription of CaHsfA2. The result of subcellular localization showed that CaBES1 was expressed in both cell membrane and nucleus. After heat stress treatment, the fluorescence signal in the nucleus was enhanced, which was consistent with the property of CaBES1 transferring from cytoplasm to nucleus when it performs its biological functions. By dynamic expression pattern analysis, under heat stress, the expression level of CaBES1 decreased firstly and then increased, which also indicates that CaBES1 can respond to heat signal and lays a foundation for the further functional study in heat tolerance. After CaBES1 was silenced in pepper, by comparing the phenotype, relative electrical conductivity and chlorophyll content of silenced plants and control plants, it was inferred that silencing of CaBES1 increased the expression of CaHsfA2 and enhanced the heat tolerance of pepper. 【Conclusion】 CaBES1 inhibits pepper heat tolerance by negatively regulating the expression of CaHsfA2.

]]> <![CDATA[Effects of Urea Slow-release Functional Fertilizer Containing Melatonin on Growth, Yield and Phosphorus Use Efficiency of Tomato under Reduced Phosphorus Application Conditions]]>

]]> <![CDATA[Genome-wide Identification and Expression Analysis of DIR Gene Family in Cucumber (<i>Cucumis sativus</i> L.) #br#]]> with bioinformatics methods, and the expression pattern analysis of DIR family genes in different tissues and stresses response were analyzed. It will lay an important foundation for further study on the biological function of cucumber DIR genes. 【Method】 With the reported HMM model file of DIR gene, the probable DIR genes ID from the cucumber protein database was firstly identified using HMMSearch program in the HMMER software package. The cucumber DIR genes were ultimately verified using online tools Pfam and SMART. The tools of ExPASy, TBtools, GSDS, MEME, MEGA, MCScanX and Circos were used to analyze the physicochemical characteristics, chromosomal distributions, gene structure, phylogenetic tree and synteny of cucumber DIR genes. Based on cucumber transcriptome sequencing big-data of different tissues and under different stresses, transcriptome sequencing analysis was re-analyzed using cucumber V3 version genome information. The data of cucumber DIR genes in different transcriptome sequencing analysis were retrieved. The expression heatmaps of DIR gene family were drawn using TBtools softwore, and the expression patterns of cucumber DIR genes in different tissues and stresses response were analyzed. 【Result】 Total of 23 DIR genes were identified from cucumber genome, which distributed to 7 chromosomes. The number of amino acids of these DIR genes ranged from 78—684, and the molecular weight ranged from 8.70—73.82 kD. Phylogenetic analysis divided the cucumber DIR genes into 3 subgroups, the structure and motif of the genes in each subgroup were similar. Synteny analysis showed that the 12 cucumber DIR genes were collinearity with 19 Arabidopsis DIR genes with 27 kinds of linear relationships, and 12 cucumber DIR genes were collinearity with 11 rice DIR genes with 19 kinds of linear relationships. While only 8 cucumber DIR genes were conservative, which were not collinearity with any DIR gene in Arabidopsis and rice. Tissue-specific expression analysis revealed that some cucumber DIR genes have low or no expression levels in all tissues including root, stem, flower, fruit, leaf and so on, some cucumber DIR genes have high expression levels in all tissues, and some DIR genes have specific expression levels in some tissues, but no or low expression levels in other tissues. This suggested that different cucumber DIR genes have tissue specific expression patterns. The expression profiles analysis of cucumber DIR genes under biotic and abiotic stresses conditions revealed that cucumber DIR gene, CsaV3_4G023490, were up-regulated expression in response to all stresses, which means this gene play an important role in the process of cucumber growth and development. 【Conclusion】 Total of 23 DIR genes were identified in cucumber, which were divided into 3 subgroups. The gene members in each subgroup were highly conserved, the gene structure and protein conserved domain were different among 3 subgroups. The expression patterns of cucumber DIR genes in different tissues and stresses response were different, which coordinately regulated the growth and development of cucumber.


]]> <![CDATA[Optimization of Drying Process in Oat Noodles Production]]> 】The effects of different drying modes, temperature, and relative humidity on drying quality and drying energy of oat noodles were studied. The models were established and multi-objective optimization was carried out to obtain the drying mode and process parameters of oat noodles with good quality and low energy consumption.【Method】The effects of nine different drying modes of temperature and humidity on the drying quality and drying energy of oat noodles were studied. The factors of the optimal cooking time, cooking loss, water absorption, ductility, hardness, chewiness, adhesiveness, bending strength, breaking distance, acidity and fatty acid value were analyzed to obtain the comprehensive evaluation value of quality and determine the optimal drying mode of oat noodle, Plackett-Burman test was used to screen the first temperature, the first relative humidity, the second temperature, the second relative humidity, the third temperature and the third relative humidity of the three-stage drying of oat noodles with variable temperature and humidity. Box-Behnken response surface test was used to optimize the drying process, and the optimal parameters were obtained and verified.【Result】The best drying mode of oat noodles was first heating and then cooling combined with dehumidification. Plackett-Burman experiment showed that the key factors of drying oat noodles were the first stage relative humidity, the second stage temperature and the second stage relative humidity. The established regression model of oat noodle drying process parameters with unit energy consumption and the comprehensive score was significant (P<0.05). Each factor has extremely significant influence on unit energy consumption. The interaction between the first relative humidity, the second temperature, and the second relative humidity was extremely significant. All factors have a significant influence on the quality comprehensive score, the order of influence was second-stage temperature>second-stage relative humidity>first relative humidity. The interaction between first relative humidity, first relative humidity and second relative humidity was significant. The optimal process parameters for three-stage variable temperature and humidity drying of oat noodles were first stage temperature of 25℃, first stage relative humidity of 88%, second stage temperature of 43℃, second stage relative humidity of 71%, third stage temperature of 35℃, third stage relative humidity of 50%. Under this condition, the drying energy of oat noodles was 93.42 kJ·g-1, and the comprehensive score was 1.02. 【Conclusion】The established quadratic polynomial regression model could be applied to analyze and predict the effects of drying process parameters on drying energy and the comprehensive score of oat noodles. Three-stage variable temperature and humidity drying could improve the drying quality of oat noodles and reduce energy consumption. The method of using experiment design and data processing technology to solve the drying process of oat noodles was comprehensive and efficient. The results were intuitive and accurate, and the experiment efficiency and accuracy were improved. This study provided a theoretical basis for industrial standard production, energy-saving, and consumption reduction of oat noodles.

]]> <![CDATA[Coupling Effects of Postponing Topdressing N Fertilizer and Intercropping on Maize Photosynthetic Physiological Characteristics]]> compared with traditional N management practices, respectively. Similarly, compared with traditional N management practices, the grain yield of sole maize in the treatment postponing of application of 20% and 10% of N was also increased by 29.7% and 13.3% and biomass yield by 19.6% and 10.3%, respectively. Compared with the monoculture maize, intercropping can increase the grain yield by 33.2%-35.1% and biomass yield by 26.8%-31.5% under the same area. Furthermore, the treatment postponing of application of 20% and 10% of N increased the population grain yield of intercropping pattern by 27.2% and 12.9% compared with the traditional N management practices. The results showed that intercropping pattern can increase the grain yield of maize compared with the sole pattern and the N fertilizer postponing application boost the improvement of grain yield in the intercropping system compared with the traditional N management practices. During the whole growth periods, intercropping increased the net photosynthetic rate, stomatal conductance, transpiration rate, and decreased intercellular CO2 concentration. Compared with traditional N management, the net photosynthetic rate the in the treatment postponing of application of 20% and 10% N was increased by 12.8% and 6.0%, the stomatal conductance by 14.0% and 6.9%, the transpiration rate by 20.5% and 9.5%, and intercellular CO2 concentration was decreased by 29.8% and 13.1%, respectively. The SPAD value under the treatment postponing of application of 20% and 10% N was increased by 7.5% and 3.7%. The principal component analysis results showed that the N fertilizer postponing application and intercropping pattern can increase the grain yield via boosting the net photosynthetic rate, the stomatal conductance, the transpiration rate, and leaf SPAD value, and decreasing intercellular CO2 concentration. 【Conclusion】The N fertilizer postponing application 20% treatment (36 kg·hm-2 N fertilizer was topdressing at maize jointing stage and 108 kg·hm-2 at 15 d post-silking stage) had the advantage of improving the photosynthetic characteristics of intercropped maize, thereby boosting the grain yield improvement.


]]> <![CDATA[Discussions on Frontiers and Directions of Scientific and Technological Innovation in China’s Field Crop Cultivation]]>

]]> <![CDATA[Effects of Meteorological Factors on Quality of Late Japonica Rice During Late Season Grain Filling Stage Under ‘early indica and late japonica’ Cultivation Pattern in Southern China]]> province, in 2018, using three the late indica rice as controls and 20 japonica rice (including 10 inbred japonica rice, 3 japonica hybrids and 7 indica-japonica hybrids) as evaluating varieties. 【Result】(1) Based on the results of clustering with grain qualities, the late indica rice varieties were classified as an unique category due to its highest aspect ratio (3.18) and high amylose content (19.40%). In compared to the late indica rice, the most of  hybrid varieties had greater brown rice rate (4.31%-5.28%,), milled rice rate (6.51%-9.33%), head rice rate (25.83%-28.34%), gel consistency (1.81%-4.27%,), alkali spreading value (11.62%-50.85%), and tasted value (2.31%-2.85%), while lower amylose content (20.98%-28.14%) and protein content (1.16%-14.85%), showing obvious improvement of rice quality. Whereas the rice quality performance response to late season were differentiated within inbred japonica varieties, and some inbred japonica rice originating from southern Jiangsu and Jiaxing (4 varieties) were similar to the those in the hybrid-japonica category; while the rest inbred japonica varieties from Jiangsu and Shanghai (6 varieties) was belonged to another category due to their relatively poor rice quality performance (high chalkiness, chalky grain rate and protein content) in the late season. (2) The rice grain qualities were closely related to climate factors during grain filling period of late rice season. The stage of 10-20 days after full heading was identified as the sensitive period of climate factors on rice qualities. The brown rice rate was was negatively correlated with daily solar radiation (R: -0.40--0.19, p<0.05), daily temperature difference (R: -0.45- -0.28, p<0.05), and positively correlated with daily minimum temperature (R: 0.24-0.53, p<0.05) and precipitation (R: 0.38-0.45, p<0.05). The chalkiness rate and chalkiness grain rate were significantly increased with the rainfall and night temperature (R: -0.37--0.16, p<0.05; R: -0.43--0.12, p<0.05), resulting in reducing rice appearance quality. Meanwhile, the rainfall and night temperature were negatively correlated with rice tasted value(R: -0.37--0.16, p<0.05; R: -0.43--0.12, p<0.05). The daily maximum temperature at grain filling stage was positively correlated with rice tasted value (R=0.37, p<0.05), while the daily minimum temperature was positively correlated with rice protein content (R=0.19, p<0.05), chalkiness (R=0.16, p<0.05) and chalkiness grain percentage (R=0.12, p<0.05). 【Conclusion】(1) In compared to the late indica rice, applying the japonica hybrids and some inbred japonica varieties in the late season could improve the milling and cooking qualities while maintained the grain taste value, but deteriorated the appearance qualities. Thereby, the improvement of rice qualities for late japonica varieties in southern rice region should focus on the integration of high-quality japonica genes with an indica gene of local adaptation, and the choice of hybrid rice (including indica-japonica hybrids and japonica hybrids) is more reliable and convenient than inbred japonica rice. The breeding of inbred japonica varieties should consider their ecological adaptability in combined with local climatic conditions. (2) The stage of 10-20 days after full heading was the key period for the effect of climate factors on rice grain quality. The great daily solar radiation and large day and night temperature differences led to a decrease in rice milling quality, but resulted in an improvement in rice appearance quality, cooking quality, and eating quality. In contrast, the increase in precipitation and the night temperature led to a decrease in eating quality. These results provided a theoretical basis for the selection of japonica rice for late season and the optimizations of agronomic practices in southern rice region.


]]> <![CDATA[SPAD value inversion of Cotton leaves based on Satellite-UAV spectral fusion]]> bjective】In order to improve the inversion accuracy of chlorophyll content in cotton leaves and grasp its spatial distribution characteristics in Xiajin county, Shandong province. 【Method】Taking Xiajin county, Dezhou city, Shandong province as the study area and Dalizhuang cotton field in Xiajin county as the test area, the relative value of chlorophyll content (SPAD value) in cotton leaves in the experimental area was measured by SPAD (soil and plant analyzer development), and obtained the near earth multispectral image of unmanned aerial vehicle (UAV) and Sentinel-2A MSI (MSI) satellite image in the study area in the same period; Then, based on the spectral reflectance of UAV and MSI satellite images, the optimal spectral parameters were constructed and selected, and the inversion model of SPAD value was established by multiple linear regression (MLR); Finally, the quadratic polynomial fitting method was used to fuse the optimal spectral parameters corresponding to UAV and Sentinel-2A MSI. By compared and analyzed the model effects before and after fusion, the inversion model was optimized, and the SPAD value inversion of the study area was realized. 【Result】The results showed that (REG-R)/(REG+R), R/G, Cl(red edge) and NDVI could be the optimal spectral parameters of SPAD value. The precision of cotton leaf SPAD inversion model based on UAV near ground image was better than that based on satellite image; After quadratic polynomial fitting, calibration R2 was increased by 0.015-0.057, RMSE was decreased by 0.457-0.638, and validation R2 was increased by 0.040-0.085, RMSE was decreased by 0.387-0.397, and RPD was increased by 0.020-0.139. The fused spectral parameters based on Sentinel-2A MSI image were input to the inversion model based on UAV data (Fused MSI-ModUAV), the high inversion accuracy of SPAD value in cotton leaves could be obtained, with the model calibration R2 up to 0.672, RMSE of 3.982, validation R2 up to 0.713, RMSE of 3.859 and RPD of 1.685. Based on the above model, two inversion prediction maps of different scales were obtained. The SPAD value of cotton leaves in the test area showed the distribution trend of high in the south and low in the north, and the study area showed the distribution trend of low in the middle and high around, which were consistent with the field situation and showed the model had a good prediction effect. 【Conclusion】Therefore, the fusion of UAV and satellite image data by using quadratic polynomial fitting method can better realize the quantitative inversion of regional high-precision crop growth indicators. The research results can enrich the theory and technology of multi-source remote sensing fusion, and provide technical reference and data support for cotton growth monitoring and precision production.


]]> <![CDATA[Effects of the changing normal and extreme climate states on maize meteorological yield in Northeast China]]> Objective】 Northeast China is the main grain production base in China, which has been significantly affected by climate change in recently. It is of great significance to understand the impact of normal and extreme climate states changes on crop yield in Northeast China for regional crop production and national food security. 【Method】In this study, we analyzed the effects of normal and extreme climate states changes on maize yield in 81 counties in Northeast China from 1980 to 2018 by the main climatic factors. 【Result】(1) The average temperature, growing degree-days (GDD), and heat degree-days (HDD) during the maize growth period showed an increasing trend, and the rising rates were 0.34 ℃·(10a)-1℃/10a, 47.07 ℃·d·(10a)-1/10a, and 5.14 ℃·d·(10a)-1/10a, respectively. Precipitation showed a decreasing trend, with the rate of 7.0 mm·(10a)-1/10a; the average temperature, GDD, and HDD increased from northeast to southwest, and precipitation showed an increased from northwest to southeast. (2) The meteorological yield of maize in Northeast China showed an increasing trend from 1980 to 1999, with a rate of 80.93 kg·hm-?2·a-1/a, while it showed a decreasing trend of 46.25 kg·hm?-2·a-1/a from 2000 to 2018. In terms of spatial distribution, it showed an increasing trend from the middle to the surrounding areas. The area with high yield was concentrated in the eastern part of Heilongjiang. Liaoning was the most stable change, the fluctuation range was stabled in the middle area. (3) By the multiple linear regression model, HDD contributed the most to meteorological yield from 1980 to 2018, and the effect was negative, which meant extreme high temperature had the greatest impact on maize yield in Northeast China and caused maize yield reduction; GDD had a positive effect and indicated the average temperature increased maize yield, and the greater GDD, the more yield increased; precipitation had a negative effect; the interaction between temperature and precipitation had a positive impact on maize yield in Northeast China. 【Conclusion】Normal and extreme climate states changes and its impact on maize meteorological yield in Northeast China from 1980 to 2018 are as follow: the normal and extreme temperature showed an overall increasing trend, and the normal precipitation showed a decreasing trend. Extreme high temperatures and normal precipitation led to a decrease in maize yield, but the average temperature increases maize yield, and the extreme high temperature had the greatest impact. In the future, it is necessary to make full use of the average temperature state and minimize the harm caused by extreme high temperature to ensure a high-stable maize production. 


]]> <![CDATA[Yield Estimation of Navelina Navel Oranges with UAV Oblique Photography]]> In this study, a small quadrotor UAV equipped with a camera was used to collect oblique photographs of the Navelina navel orange orchard using a multi-oriented mode, flying at a height of 20 meters, with the heading overlap of 75% and the side overlap of 70%. The orchard point cloud data of the orchard, namely digital surface model (DSM), was obtained based on the 3D reconstruction of the orchard images, and the non-ground points were filtered to generate digital terrain model (DTM). The canopy height model (CHM) data were obtained by subtracting DTM and low vegetation from the DSM in turn, and the canopy characteristics, such as tree height, canopy projected area and canopy volume of individual trees, were extracted. The optimal yield estimation phenological period was determined based on the correlation between the production and the canopy characteristics in the three main physiological phenological periods, i.e. the second physiological drop (SPD) period, the turning stage (TU) period and the mature period. Then, the Levenberg-Marquardt (LM) algorithm was used to establish the yield estimation models of navel orange with different combinations of canopy characteristics extracted from the optimum phenological period. Finally, the obtained yield models were evaluated, analyzed and optimized to establish the optimal yield estimation model for Navelina navel oranges, and the model was validated by the validation set. 【Result】The determination coefficients (R2) between the measured tree height, canopy projected area and canopy volume based on UAV oblique photography and manual measurements were 0.99, 0.79 and 0.88, respectively, which shown that this method could be used to obtain canopy information with higher efficiency instead of manual measurements. By analyzing the relationship between yield and canopy information at different phenological periods, the SPD was selected as the optimal yield estimation phenological period. The optimal yield estimation model of Navelina navel orange based on canopy volume in SPD was developed using LM algorithm with R2=0.7961 and RMSE=11.85. The absolute mean relative error of the sample plants in the validation set was 4.43%. 【Conclusion】The results showed that it was feasible to collect the image of Nevelina navel orange orchard in the SPD by UAV oblique photography technology, to extract the individual canopy characteristics from the orchard point cloud through three-dimensional reconstruction, to establish the yield estimation technology of Nevelina navel orange using LM algorithm.


]]> <![CDATA[Effects of Drip Irrigation under Film and Trickle Furrow Irrigation on Maize Growth and Yield]]> 】The effects of drip irrigation and trickle furrow irrigation on maize growth, yield and water use efficiency were studied.【Method】Taking Zhengdan 958 as the research object, a field experiment was conducted from 2015 to 2021. The soil water content of 0-50 cm under narrow row, root zone and wide row was measured by a tubular moisture meter to study the effects of drip irrigation and trickle furrow irrigation under film on soil water distribution and its effects on maize plant height, leaf area index, chlorophyll content, biomass, yield and water use efficiency.【Result】Drip irrigation under mulch gives priority to supplement soil moisture in narrow row and root zone, while trickle furrow irrigation gives priority to supplement surface moisture in wide row. The water consumption of maize was mainly concentrated in 0-30 cm soil layer, and the soil water content in narrow row and 0-30cm root zone of drip irrigation under film was higher than that of trickle furrow irrigation; With the increase of depth, the effect of irrigation on soil water content decreases, and the 40-50 cm water dynamics is less affected by irrigation methods. Drip irrigation under mulch could significantly promote the growth of Maize at flowering and mature stages and increase leaf area index compared with trickle furrow irrigation. Compared with trickle irrigation, the plant height and leaf area index of drip irrigation under film increased by 4.3% and 8.3% at flowering stage, and increased by 4.9% and 15.1% at mature stage. The total biomass of Maize at flowering stage and mature stage was drip irrigation under film > trickle furrow irrigation treatment, with an increase of 11.8% at flowering stage. The mature period increased by 11.5%. The amount of dry matter transfer, the rate of dry matter transfer and the contribution rate of dry matter transfer of Maize under drip irrigation were significantly higher than those under trickle irrigation, increasing by 17.8%, 3.8% and 3.5% respectively. Drip irrigation under plastic film significantly increased maize yield and irrigation water utilization rate, with an average yield increase of 14.4%, and irrigation water utilization rate increased by 14.3%.【Conclusion】Under the condition of equal irrigation volume, drip irrigation under film can increase the water content in maize root zone, promote the growth of maize, facilitate the accumulation and transportation of dry matter of maize, improve the yield, and achieve water saving and efficiency increasing; Compared with trickle furrow irrigation, the average yield increased by 2131.68 kg hm-2, and the irrigation water use efficiency increased by 8.8%-24.1%. Therefore, drip irrigation under plastic film is a high-yield and efficient irrigation method for maize planting in Northern Xinjiang.


]]> <![CDATA[Hyperspectral Prediction of Organic Matter in Soils of Different Salinity in the Yellow River Delta]]> , R) were subjected to frist order differential reflectance (first order differential reflectance, FD), continuous statistical removal (continuous statistical removal, CR), logarithmic (logarithmic, Log) and multiple scatter correction (multipication scatter correction, MSC) transformations were applied to the raw spectra reflectance; finally, three soil organic matter

prediction models, namely multiple linear regression （multiple linear regression, MLR）, partial least squares regression (partial least squares regression, PLSR) and support vector regression (support vector machine, SVR), were constructed based on four sets of samples of saline soils combined with the four transformed spectra, respectively. 【Result】Soil organic matter and salinity had significant spectral response in the range of 400-900 nm and the change pattern were the same basically, and the sensitive bands of the two overlap; modeling by dividing different salinity could improved the prediction accuracy of soil organic matter, and the prediction accuracy of the model decreased with the increase of salinity content, FD treatment could better highlight the difference of spectral characteristics and improved the correlation between organic matter content and spectral reflectance. Comparing the results of the three models, the highest accuracy of the soil organic matter prediction model was established using FD treatment combined with SVR, and the coefficients of determination R2 of the optimal result modelling set and validation set were 0.86 and 0.82, the root mean square error RMSE was 2.71 g·kg-1 and 2.96 g·kg-1, and the ratio of prediction to deviation RPD was 2.42. 【Conclusion】Soil salinity and organic matter overlaped in the sensitive bands near the visible wavelength (400-900nm), and the accuracy of the organic matter prediction model could be effectively improved by classifying different salinity levels.

]]> <![CDATA[Effects of Long-Term Fertilization on Nitrogen Accumulations and Organic Nitrogen Components in Soil Aggregates in Yellow-Mud Paddy Soil]]> 】Nitrogen is an important limiting factor in sticky and thin medium-low-yield paddy soil in southern China. In order to provide the basis for reasonable fertilization and soil nitrogen pool management, the effects of long-term fertilizations on nitrogen accumulations and organic nitrogen components in soil aggregates in a yellow-mud paddy soil were investigated.【Method】Soil samples from the plough layer in the 36th year under different fertilization treatments in the long-term experiment of yellow-mud paddy soil were collected to analyze the nitrogen accumulation and the contents of organic nitrogen components as well as their distributions in aggregates by wet screening and Bremner organic nitrogen classification method. The treatments included: no fertilization (CK), application of chemical fertilizer (NPK), chemical fertilizer plus cow dung (NPKM) and chemical fertilizer plus total rice straw returning (NPKS). 【Result】 The contents of total nitrogen in >2 mm aggregate were significantly increased by 12.7%-51.9% in fertilization treatments compared with that in CK (P<0.05). The cumulative contribution ratios of TN in >2 mm aggregate to total nitrogen in bulk soil in NPKM and NPKS treatments were 24.7 and 20.0 percentage points significantly higher than that in CK (P<0.05), respectively. The contents of acid-hydrolyzable nitrogen (AHN) and non-hydrolyzable nitrogen (NHN) in >2 mm aggregate in fertilization treatments were increased by 10.1%-36.3% and 20.7%-100.5% compared with those in CK, respectively, and the cumulative contributions of the two components to total nitrogen in bulk soil were increased as well, especially for NPKM and NPKS treatments.  In >2 mm aggregate, the contents of acid-hydrolyzable ammonia nitrogen (AMMN) in fertilization treatments were significantly increased by 17.2%-40.4% compared with that in CK (P<0.05), and the largest increasement was found in NPKM treatment. The contents of acid-hydrolyzable amino acid nitrogen (AAN) and acid-hydrolyzable unknown nitrogen (HUN) were increased most significantly in NPKS and NPKM treatments, which were 24.0% and 52.1% higher than those in CK (P<0.05), respectively. The contents of NHN and AMMN in >2mm and 0.25-2 mm aggregates were all significantly positively correlated with the contents of alkaline nitrogen in corresponding aggregates (P<0.05).  Redundant analysis (RDA) showed that the nitrogen uptake of rice plant was mainly affected by NHN components in >2 mm and 0.25-2 mm aggregates. The nitrogen uptake of rice plant was more affected by soil organic nitrogen components under NPKM and NPKS treatments than that under NPK and CK treatment.【Conclusion】The contents of total nitrogen in >2 mm aggregate and their cumulative contributions to total nitrogen in bulk soil were increased in plough layer of yellow-mud paddy soil under long-term fertilizations, especially for the combined application of organic and inorganic fertilizers. Compared with combined application of cow dung, combined application of  rice straw returning was more conducive to the accumulation of NHN in >2 mm aggregate. In >2 mm aggregate, combined application of cow dung had the biggest contribution to the increase of AMMN and HUN contents, and their cumulative contribution ratios to total nitrogen in bulk soil, while combined application of rice straw returning had the largest contribution to the increase of AAN content and their cumulative contribution ratio to total nitrogen in bulk soil. The contents of NHN, AHN and AMMN in >2 mm aggregate were closely related to alkaline nitrogen and the nitrogen uptake of rice plant in yellow-mud paddy soil, which were important available nitrogen pool. 


]]> <![CDATA[Effects of Long-term Conservation Tillage on Soil Carbon Content and Invertase Activity in Dry Farmland on the Loess Plateau]]> 】The effects of long-term conservation tillage on soil carbon and carbon invertase activity in forage-crop rotation system of dry farmland in the Loess Plateau were explored to provide scientific basis for soil carbon sequestration and sustainable and healthy development of agriculture in dry farmland. 【Method】In this study, we aimed to investigate the effects of long-term traditional tillage (T), no-tillage (NT), traditional tillage+straw mulch (TS), and no-tillage+straw mulch (NTS) on soil organic carbon (SOC), microbial biomass carbon content (MBC), β-glycosidase (βG), cellobiohydrolase (CBH) and β-xylosidase enzymes (βX) in forage-crop rotation system at the National Field Scientific Observation and Research Station of the Grassland Agricultural Ecosystem in Qingyang, Gansu Province. Soils were collected from 0-5, 5-10 and 10-20 cm depths at the harvest of maize (Zea mays L.). 【Result】(1) Conservation tillage significantly increased the contents of SOC and MBC in soil, especially in 0-5 cm soil layer. Compared with conventional tillage, straw mulching increased SOC and MBC by 19.11% and 39.88%, and no-tillage increased SOC and MBC by 15.13% and 34.34%, respectively. (2) Conservation tillage significantly increased soil carbon invertase activity, the three enzyme activities showed: βG>CBH>βX, the sensitivity of conservation tillage measures showed: CBH>βX>βG. Compared with traditional tillage, the activities of βG, CBH and βX in 0-5 cm soil layer under straw mulching increased by 20.26%, 37.62% and 41.06%, respectively, and those under no-tillage increased by 12.47%, 30.99% and 26.12%, respectively. Straw mulching in 5-20 cm soil layer increased βG, CBH and βX by -7.57%, 99.86% and 3.50%, respectively, and no-tillage increased them by -21.05%, 22.11% and -12.11%, respectively. In addition, the structural equation results showed that soil carbon invertase activity was mainly affected by soil total nitrogen content in forage-crop rotation system. (3) Straw mulching can directly affect the accumulation of soil carbon, mainly affecting the activity of soil carbon invertase by changing the soil total nitrogen content; no tillage has no significant impact on soil environment, resulting in no significant changes in soil carbon content and carbon invertase activity.【Conclusion】The accumulation of soil carbon was mainly affected by the direct effect of straw mulching measures, and the activity of carbon invertase was mainly changed by the indirect effect of soil total nitrogen in the forage-crop rotation system of dry farmland in the Loess Plateau. Among them, no tillage combined with straw mulching is the most effective measure to improve soil carbon content and enzyme activity, β- Glucosidase is the main enzyme involved in soil carbon inversion.


]]> <![CDATA[Response of Carbon and Nitrogen Distribution in Organo-Mineral Complexes of Red Paddy Soil to Long-term Fertilization]]> 】The effects of long-term fertilization on the distribution of organic carbon (OC) and total nitrogen (TNOIC) of organo-mineral complexes in red paddy soil were studied, which provided a basis for long-term management and cultivation of soil fertility in red paddy soil. 【Method】The red paddy soils in long-term fertilization experiment were studied (Since 1984), which include four treatments: no fertilization (CK); inorganic P and K fertilizers (PK); inorganic N, P and K fertilizers (NPK) and NPK plus manure (NPKM, 70%NPK plus 30% manure). Soil samples of 0-20 cm were collected and the distribution of organo-mineral complexes at each particle level (<2 μm, 2-10 μm, 10-20 μm, 20-50 μm, 50-250 μm) was analyzed. The effects of fertilization on the content, storage of organic carbon and total nitrogen as well as the carbon-nitrogen ratio (C/N) were discussed. And the effects of SOC and TN contents in organo-mineral complex on contribution rate of SOC and TN contents in red paddy soil.【Result】Compared with the CK treatment, fertilization treatment significantly increased the particle size ratio of 20-50 μm and decreased the particle size ratio of <10 μm. Compared with other fertilization treatments, NPKM treatment increased the proportion of 50-250 μm grain size complex more significantly. Different fertilization had different effects on the content of OC and TNOIC in grain size. Compared with PK, the content of OC and TNOIC in grain size from 50 μm to 250 μm under NPK treatment increased 36.3% and 80.6%, respectively.  Compared with NPK, the content of OC and TNOIC in 50-250 μm granular complex increased by 35.4% and 19.5% in NPKM treatment, respectively. The SOC and TNOIC storage of the organic and inorganic complexes were mainly distributed at the 10-20 μm particle level. And fertilization significantly reduced the storage of <2 μm particle-level complex OC and TNOIC, but increased the storage of OC and TNOIC at 20-50 μm particle-level. Compared with PK treatment, the OC storages of <2 μm and 50-250 μm particle-level complexes treated by NPK increased by 18.5% and 31.2%, respectively, and the storages of TNOIC increased by 18.8% and 73.7%, respectively. Compared with NPK, the NPKM treatment reduced the SOC and TN storages of the <2 μm particle-level complex by 25.6% and 27.4%, respectively, while OC and TNOIC storages of 50-250 μm particle-level complex increased by 56.3% and 38.6%, respectively. Fertilization significantly influenced the C/N ratio of 50-250 μm particles. Compared with PK, the C/N ratio of 50-250 μm fraction treated with NPK decreased by 24.6% and compared with NPK, the C/N ratio of 50-250 μm fraction treated with NPKM was increased by 13.4%. Fertilization significantly affected the contribution rate of organo-mineral complexes of each particle size to soil SOC and TN content. Compared with PK, the contribution rate of NPK treatment 50-250 μm particle-level complex to SOC and TN increased by 17.4% and 47.4%, respectively. Compared with NPK, the contribution rate of NPKM treatment 50-250 μm particle to SOC and TN were reduced by 39.5% and 32.8%.【Conclusion】In red soil paddy soil, long-term fertilization promoted the formation of large-grain organo-mineral complexes. The nitrogen input in the chemical fertilizers significantly increased the grain-level organic carbon, total nitrogen content and storage of the granular grade of 50-250 μm. The organo-mineral combined application is conducive to increasing the soil organic carbon content and the proportion of large-grain organo-mineral complexes, which is helping to preserve the inorganic nitrogen fertilizer applied. Therefore, organic and inorganic compound application is an effective measure for long-term fertilization management of red paddy soils.  


]]> <![CDATA[Effects of Straw Incorporation Quantity on Soil Physical Characteristics of Winter Wheat-Summer Maize Rotation System in the Central Hilly Area of Sichuan Basin]]> 】To ascertain the effect of straw returning quantity on the soil physical characteristics and establish a recycling model for planting by-products. At the same time, to provide a scientific basis for the utilization of straw resources in the central hilly area of Sichuan basin.【Method】Herein, we examined the effects of different amount of straw returned to the field (0% straw returned (RMW0), 30% straw returned (RMW30), 50% straw returned (RMW50) and 100% straw returned (RMW100)) on the physical characteristics at the cultivated soil layer of the winter wheat-summer maize rotation system, based on long-term field trials (2006-present) using a combination of in situ monitoring and computed tomography microscanning (CT).【Result】(1) Straw returns to the field could significantly improve soil permeability, water holding capacity and hydraulic conductivity, and the improve effect increases significantly with the amount of straw returned to the field . Compared to the RMW0 treatment, soil bulk density in RMW30, RMW50 and RMW100 treatments reduced significantly by 15.2%, 11.7% and 17.9%, respectively. Whereas soil porosity of these treatments were significantly increased by 18.4%, 13.7% and 21.3%, respectively. In addition, the Saturated hydraulic conductivity of RMW100 treatment was as high as 1.62 mm min-1, and the soil hydraulic conductivity was superior to other treatments. (2) Straw returning promoted the development of existing pores into larger ones and significantly improved pore uniformity and connectivity. The RMW100 and RMW50 treatments improved the macropore composition of the soil better than that of the RMW30 and non-return treatments. The average pore diameter of the RMW100 treatment tends to be larger and inter-pore connectivity is optimal. The homogeneity of the pores in the RMW50 treatment was significantly improved and the pore size distribution was more appropriate than that of other treatments. (3) Compared to the RMW0 treatment, the number of >2 mm agglomerates increased significantly and the number of 0.25-2 mm agglomerates decreased significantly after straw returned to the field, which was beneficial to the formation of large soil water-stable agglomerates and promoted the transformation of medium to large agglomerates. Both RMW50 and RMW100 treatments improved significantly better than that of RMW30 treatment. (4) Principle components analysis showed soil bulk density, water-stable aggregate with diameter larger than 0.25 mm and large pore were the main indicators of the physical characteristics of cultivated soils in calcareous purple soils. The first and second principal components explained 57.8% and 23.62% of the physical properties of the soil. The physical characteristics of RMW50 and RMW100 treatments were close to each other, and showed significant divergence from the RMW0 and RMW30 treatments on the PC1 and PC2 axes. 【Conclusion】On the basis of no significant difference of crop yield in the central hilly area of Sichuan basin, there were differences in the effects of different straw returning quantities on the physical properties of cultivated soil layer, with no significant differences between 50% and 100% straw returning effects, but significantly better than that of 30% and 0% of straw incorporation. The specific straw application rate should be selected according to the local conditions.


]]> <![CDATA[Decomposition Characteristics of Straw and Organic Fertilizer Mixed Soil after Landfill in Typical Area]]> , and Rotary tillage is the main way of returning farmland. The characteristics and driving factors of their decomposition process in typical farmland soils in China are studied to provide a scientific basis for better utilization of straw resources and rational application of manure.【Methods】The landfill experiment of field organic material mixed with soil was carried out on a typical black soil, fluvo-aquic soil and red soil in China. Four treatments were set up: wheat straw plus soil (WS+Soil), Maize straw plus soil (MS+Soil), Pig manure plus soil (PM+Soil) and Cow manure plus soil (CM+Soil). All the organic materials (8 g carbon) were mixed with 200 g of soil in a nylon mesh bag buried in soil, Six samples are taken within one year after landfilling, once from 2 to 2.5 years after landfilling, and once in 4 years. A total of eight samples are taken. The decomposition differences of organic materials in different mixtures were analyzed. The double exponential equation was used to clarify the proportion and decomposition rate of easy-to-decompose carbon pool and refractory organic carbon pool, and to clarify the fast decomposition rate, slow decomposition rate and accumulated temperature turning point of organic materials in each soil. The Random forest model was used to quantify the relative contribution of material composition and environmental factors to the decomposition rate. 【Results】The humification coefficient of straw pluil was ranged from 22% to 43%, and that of manure plus soil was ranged from 45% to 58%. The decomposition rate of manure plus soil was slower than straw plus soil, and there was little difference between regions. Besides, the decomposition of organic materials was accelerated from north to south, and the decomposition of straw was faster than that of organic fertilizers. The proportion of decomposable organic carbon of straw (70%-87%) was higher than that of organic fertilizer (57%-79%), and the decomposition rate of straw decomposable carbon pool K1 ((1.0-4.9)%·a-1) was higher than that of organic fertilizer K1( (0.7-1.1)%·a-1). There was little difference in the turning point of accumulated temperature of straw in the three types of soil. Before 3.7 × 103 ℃, it is the stage of rapid decomposition， and then it is the stage of slow decomposition. On the other hand, the difference in accumulated temperature at the turning point of rapid decomposition and slow decomposition of organic fertilizer gradually increased from north to south, and the accumulated temperature at the turning point of organic fertilizer was 2-5 times higher that of straw. Soil accumulated temperature and soil organic carbon content were the main driving factors of mixed soil straw and organic fertilizer, contributing about 17% and 13% of the decomposition rate, respectively. In addition, the main driving factor for mixed soil straw is the ratio of soil carbon to nitrogen, but the main driving factor for mixed soil organic fertilizer is the time.【Conclusion】Straw returning to the field decomposes faster than organic fertilizer, and the high proportion of easily decomposable organic carbon pool and fast decomposition rate of straw is one of the main reasons for the difference. For straw, the ratio of carbon to nitrogen is the main factor affecting its decomposition, and for organic fertilizer, it is time. Therefore, the ratio of carbon to nitrogen of soil and material should be considered to regulate the decomposition of straw, the long-term effect of organic fertilizer should be fully considered.


]]> <![CDATA[Environmental Safety Risks in Agricultural Application of Effluents From Sugar Molasses-based Fermentation Industries]]> <![CDATA[Mining of Genetic Locus of Maize Stay-green Related Traits Under Multi-environments]]> 】Functional stay-green is generally considered a desirable trait in major crop varieties including maize. Finding new loci and candidate genes related to stay-green, and providing new theoretical basis for the genetic research on stay-green. 【Method】Using 150 recombinant inbred lines(RIL)populations derived from the cross between Xu 178 and K12, QTL mapping of three stay-green related traits (visual stay green (VSG), green leaf number at silking stage (GLNS) and green leaf number at mature stage (GLNM) were performed by the composite interval mapping（CIM）method of Windows QTL Cartographer V2.5. Besides, an association population, which composed of 139 natural materials genotyped with 50790 high-quality SNP markers, was used to dissect genetic locus of three traits by genome-wide association study (GWAS) based on the mixed linear model MIM). 【Result】Based on CIM, three traits (GLNM, GLNS and VSG)were mapped using phenotypic values in a single environment and best linear unbiased prediction (BLUP) value. A total of 37 QTLs were detected on all chromosomes except Chr. 10, and the LOD score ranged from 2.58-11.36, with a phenotypic variation contribution rate of 4.34%-22.40%. Among them, 14, 12 and 11 loci were detected for GLNM, GLNS and VSG traits, respectively. Four of the QTLs, qGLNS2-1, qVSG1-1, qVSG1-2 and qVSG7-1, were genetically stable and were detected simultaneously in three or more different single environments. GWAS was performed on three stay-green related traits using MIM, and a total of 44 significant SNPs above the threshold line were detected. According to the physical position of SNP markers in the B73 reference genome, a total of 15 SNP were found to fall into the QTL interval mapped by linkage analysis.【Conclusion】Combined with the results of QTL mapping and genome-wide association study, a total of 4 genetically stable colocalization genetic regions were detected(the corresponding physical position intervals on the B73 reference genome Version 4 are 6.2-8.2 Mb on chromosome 1, 209.1-221.4 Mb on chromosome 2, 96.8-102.1 Mb on chromosome 6, and 4.9-11.4 Mb on chromosome 7) , and four important candidate genes (Zm00001d006119, Zm00001d018975, Zm00001d006535 and Zm00001d036763) related to photosynthesis and stress response were mined.


]]> <![CDATA[PSORA: A Strategy for High-Throughput Analysis of T-DNA Insertion Sites]]> 】The purpose of this study was to establish a simple and efficient approach for identifying all T-DNA insertion sites. 【Method】A T-DNA insertion sites analysis approach based on high-throughput sequence technologies was developed, called PSORA: Parallel sequencing of one round amplicons. The process involves high-throughput amplicon sequencing of a round of thermal asymmetric PCR (TAIL-PCR) and bioinformatics analysis of T-DNA insertion sites, which reduces concerns about the specificity of TAIL-PCR. In PSORA, only two primers are required, a degenerate primer and a T-DNA specific primer. A 6-nt Barcode was designed at the 5 'end of the specific primers for labeling different transgenic events. All five transgenic events (L1, L6, L9, L15 and L19) of tobacco used in this study were produced via Agrobacterium mediated transformation with plasmids pBI121. In addition, the results of PSORA are confirmed by standard PCR. 【Result】The T-DNA insertion sites of five transgenic events were analyzed by PSORA. The results showed that L6 contained two insertion sites (36 316 bp on NW_015801367 and 42 202 bp on NW_015950898), the lines of L9, L15 and L19 each contained one insertion site (The insertion site of L9 was located at 235 969 bp on NW_015943682. The insertion site of L15 was located at 60 529 bp on NW_015802951 and the insertion site of L19 was located at 12 188 bp on NW_015863435.), but the insertion site of L1 could not be detected. PCR was performed to validate the results from bioinformatics analysis, transgenic events with different insertion sites were used as negative controls for each other, and the wild type (WT) was used as a blank control. The results showed that specific amplification consistent with expectations was obtained in each transgenic event. The effectiveness of PSORA was successfully confirmed. 【Conclusion】PSORA is an effective strategy to analyze T-DNA insertion sites. PSORA can parse the comprehensive molecular characteristics of all T-DNA insertion events simultaneously, making it simpler and faster than the traditional methods of genome walking.


]]> <![CDATA[The Functional Analysis of High Mobility Group <i>Ms</i><i>HMG-Y</i> Involved in Flowering Regulation in <i>Medicago sativa </i>L<i>.</i>  #br#]]> 】Flowering is an important signal indicating the transformation from vegetative growth to reproductive growth and has a significant effect on plant biomass. Alfalfa is one of the upmost forage crops worldwide, its yield and quality are closely related to flowering time. The optimum harvest time for alfalfa is during the early flowering stage, which could give the highest yield and the best quality. In the current study, an alfalfa flowering related gene, Medicago sativa High Mobility Group Y (MsHMG-Y), was cloned. The gene structure and expression pattern of MsHMG-Y were studied. Function of MsHMG-Y in alfalfa flowering regulation was analyzed. This work could provide theoretical support for mechanism study underlying flowering regulation. 【Method】MsHMG-Y was cloned by homology cloning strategy and the amino acid sequence was analyzed by multiple sequence alignment. The phylogenetic tree was also constructed. qRT-PCR analysis was used to detect the expression level of MsHMG-Y in different tissues and different flowering stages. The expression pattern of MsHMG-Y under light, gibberellin (GA3), salicylic acid (SA) or methyl jasmonate (MeJA) treatment were analyzed. The phenotype of MsHMG-Y-overexpressing alfalfa was analyzed, and the expression levels of flowering activators and suppressors were also analyzed. 【Result】Phylogenetic analysis showed that MsHMG-Y has the closest relationship with MtHMG-Y in Medicago truncatula. Spatial expression pattern analysis showed that MsHMG-Y was expressed in flowers, stems and leaves, with the highest expression level in flowers and the lowest expression level in leaves in both paternal and maternal alfalfa. In paternal alfalfa with early flowering phenotype, the expression level of MsHMG-Y was the highest at early flowering stage. The highest expression level of MsHMG-Y was detected at flower bud differentiation stage in maternal alfalfa with late flower phenotype. Photoperiod analysis showed that MsHMG-Y was down-regulated after 16-hour light treatment. After 28 hours of light treatment, the expression level of MsHMG-Y was continuously lower than that in the control group, indicating that MsHMG-Y was down-regulated after light treatment. After 50 μmol·L-1 GA3, 100 μmol·L-1 SA or 100 μmol·L-1 MeJA treatment, the expression level of MsHMG-Y was up-regulated compared with the mock treatment. In detail, the expression level of MsHMG-Y was the highest at 1 h under GA3 treatment, which was 3.5 folds higher than control. Under SA treatment, the expression level of MsHMG-Y was the highest at 6 h, which was 24 folds higher than the mock treatment. The expression level of MsHMG-Y was the highest at 3 h under MeJA treatment, which was 11 folds higher than the control. These results indicated that the expression of MsHMG-Y was inducible by the above three hormones. MsHMG-Y-overexpressing alfalfa has late flowering phenotype. The expression levels of flowering activator genes were down-regulated in MsHMG-Y-overexpressing alfalfa, while the expression levels of flowering inhibitor genes were up-regulated. Among these genes, expression of flowering activator genes MsPHYA, MsGI and MsFTa1 was significantly down-regulated by 4.9 folds, 3.9 folds and 2.8 folds respectively, and the expression level of flowering inhibitor genes MsTEM and MsSVP was increased by 2.5 folds and 1.9 folds, respectively. 【Conclusion】The expression of MsHMG-Y is inducible by photoperiod and exogenous hormone treatment, including GA3, SA and MeJA. Overexpression of MsHMG-Y in alfalfa resulted in delayed flowering time. MsHMG-Y plays an important role in regulatory mechanism underlying late flowering in alfalfa.


]]> <![CDATA[Effect of Salicylic Acid Priming on Salt Tolerance of Kenaf Seedlings]]> 】To study the growth and physiological response of Salicylic acid (SA) priming in kenaf under salt stress, and further reveal the induction pattern of SA priming on the stress-related genes in kenaf, thus provide a theoretical basis for salt tolerance study in kenaf. 【Method】Two different salt-tolerant kenaf cultivars (resistant and sensitive cultivars codenamed CP018 and CP047, respectively) were used as materials. The seeds were tested by SA priming and then subjected to hydroponics experiments to analyze the effect of SA priming on kenaf seed germination and the agronomic and physiological aspects of seedling under 150 mmol·L-1 NaCl stress, and the expression patterns of SA priming stress-related genes were analyzed by qRT-PCR.【Result】The germination rate, germination potential and germination index of the salt-resistant cultivar CP018 were significantly improved after 0.2 mmol·L-1 SA priming, by 34.78%, 31.30% and 58.07%, respectively; the salt-susceptible cultivar CP047 also showed some improvement, by 7.50%, 10.56% and 6.23%, respectively, but did not reached the significant level. Under salt stress conditions, plant height inhibition was significantly reduced by 4.07% (CP018) and 3.91% (CP047) in the 2 cultivars by SA priming (S1) compared with un-priming (N1), and dry weight inhibition was significantly reduced by 15.50% (CP018) and 15.68% (CP047), in the 2 cultivars, respectively; fresh weight inhibition was significantly reduced by 4.46% in CP047, but not in CP018. Analysis of the root systems showed that root length inhibition was significantly reduced by 10.74% (CP018) and 10.77% (CP047) in the two cultivars, respectively, root surface area inhibition decreased by 5.09% (CP018) and 2.95% (CP047) in the two cultivars, reaching a significant level only in the salt-resistant cultivar CP018, while root activity inhibition was significantly reduced by 46.21% in the salt-susceptible cultivar CP047 and 6.56% in the salt-resistant cultivar CP018, reaching a significant level only in the salt-susceptible cultivar CP047. A grey correlation analysis of the indicators revealed that root activity was the most relevant factor influencing plants dry weight. SA priming reduced the MDA content and increased the POD and SOD enzyme activities of kenaf leaves under salt stress. Expression analysis of 12 stress-related genes showed that ACCD, APX2, SOS1, ARR2, PAL, CHIT and TIFY11 genes expression levels were significantly up-regulated after SA priming, while ERF9, ERS1, ERF.C3 and MYC2 and XTH22 expression patterns differed between the two cultivars, with XTH22 being significantly up-regulated in salt sensitive cultivar CP047 but not in the salt resistant cultivar CP018, ERS1 and MYC2 were significantly up-regulated in the salt resistant cultivar CP018 but significantly down regulated in the salt sensitive cultivar CP047, while the trend of ERF9 was opposite in the two cultivars.【Conclusion】SA priming at a suitable concentration could significantly alleviate the growth of kenaf under salt stress, and differed in the degree and patterns of effects on different kenaf germplasm resources. SA may regulate kenaf plant response to abiotic stresses by affecting physiological processes such as antioxidant enzyme systems and mediating the expression of specific genes.


]]> <![CDATA[Cloning of the soybean single zinc finger protein gene GmSZFP and its functional analysis in SMV-host interactions]]> 2O2 production and have identified a differentially expressed C2H2-type single zinc finger protein gene, Glyma.18G003600.1, named GmSZFP. In this study, we use virus induced gene silencing (VIGS) technique to investigate the function of GmSZFP in soybean-SMV interaction, providing a foundation for further investigation of the molecular mechanism of GmSZFP in soybean-SMV interaction.【Method】Soybean cultivar Jidou 7 and SMV strains SC-8 (susceptive) and N3 (resistance) were used as the materials in this study. Bioinformatic analysis was conducted to predict the protein domains of GmSZFP; its transcription factor activity was measured by transcriptional activation assay in yeast; the expression characteristics of GmSZFP at the transcriptional level in soybean-SMV interaction were verified by real-time quantitative PCR (qPCR); and the function of GmSZFP in soybean-SMV interaction was investigated by VIGS technique. 【Result】The CDS region of GmSZFP gene was cloned; amino acid sequence analysis and transcriptional activation assay in yeast revealed that GmSZFP is a C2H2-type zinc finger protein transcription factor with transcriptional activation activity; qPCR results showed that GmSZFP was strongly induced by SMV inoculation, and the expression pattern was different between the compatible and the incompatible combinations. The expression of GmSZFP was elevated after SMV inoculation, and then decreased in the incompatible combination, and the expression level of GmSZFP was significantly lower in the compatible combination than that in the former. Moreover, the expression level of GmSZFP was found to be reduced to the level that is similar to the level in the compatible combination that was pre-inoculated with imidazole, indicating that GmSZFP responds to SMV infestation at the transcriptional level and is regulated by H2O2; After silencing GmSZFP, we found that callose at the SMV inoculation site was greatly reduced compared to the control, and the expression of callose synthase genes GmGSL7c and GmGSL12b was reduced compared to the control, and the expression of callose hydrolase gene BG was elevated compared to the control; In addition, after GmSZFP was silenced, the virus spread outward to a distance of 2 mm at 72 h and to a distance of 3 mm at 96 h from the central source after SMV was inoculated in a small area, while the expression of SMV capsid protein (CP) gene was not detectable outside the inoculation site in control leaves; 10 d after SMV inoculation, the upper leaves (of the SMV inoculated leaves) in the GmSZFP-silenced plants showed mosaic, greening and curling symptoms, and CP gene was expressed, indicating that silencing of GmSZFP enabled SMV to transport in an unrestricted manner.【Conclusion】GmSZFP is a canonical C2H2-type mono-zinc finger protein, and the GmSZFP gene plays a positive regulatory role in soybean resistance to SMV infection. 


]]> <![CDATA[QTL mapping for traits related to seed number per pod in Peanut (<em>Arachis hypogaea</em> L.)]]> Objective】Peanut (Arachis hypogaea L.) is one of the important vegetable oil and cash crop. High yield is always the predominant objective in peanut breeding and determined by seed number per unit area and seed weight. Seed number per unit area is produced by planting density per unit area×number of pods per plant×number of seeds per pod. Therefore, the genetic dissection of the number of seeds per pod is helpful to explore the gene/locus related to this trait, which provides an important theoretical basis for the molecular breeding of yield in peanut.【Method】A RIL population, derived from Silihong×Jinonghei 3, were planted at Qingyuan experimental station of Hebei Agricultural University in Baoding city Hebei province in 2018(E1) and 2020(E2) . Phenotypic values of traits associated with the number of one seed pods per plant, two seeds pods per plant and multiple pods per plant were investigated at harvest stage. By using the genetic linkage map constructed by laboratory of Peanut innovation team, Hebei Agricultural University and software of QTL Icimapping V4.1(the Inclusive composite interval Mapping (ICIM)), QTL mapping for the number of seeds per pod was carried out under two environments.【Result】The results showed that the rates of one seed pods per plant and two seeds pods per plant were normal distribution, while the rate of multiple pods per plant was skewed normal distribution. A total of 11 QTLs were detected for the three traits, which could explain the phenotypic variation of 4.66%-22.34% and the additive effects of -9.35-9.42. Among of them, 5 QTLs for the rate of multiple pods per plant with explained 3.19% to 22.34% of phenotypic variation were obtained. The additive effect of one QTL was negative (-4.77), and the allele was provided by the male parent, while the additive effect of the other four QTL was positive (3.59-9.42), and the alleles were supplied by female parent. Two QTLs for the rate of one seed pods per plant were mapped with explained 4.97%-6.43% of phenotypic variation. The additive effects of the two QTLs were negative (-4.45 and -4.54), and the alleles were provided by the male parent. Four QTLs for the rate of two seed pods per plant were located with explained 4.97%-6.43% of phenotypic variation. The additive effects of the four QTLs were negative (-9.35--3.84), and the alleles were provided by the male parent. Among of these QTLs, 6 QTLs were major QTLs, of which qRMSPA05 was repeatedly detected, and the heritable phenotypic variation was 16.58%-17.34%, and. the additive effect was 7.69-8.12.【Conclusion】Six major QTLs and one major stable QTL for multiple pods per plant were identified, which will be helpful for improving the yield traits in peanut. The results can be used as important candidate segments for genetic improvement, and molecular marker assisted selection and fine mapping.


]]> <![CDATA[Comprehensive Evaluation and Potato Tuber Texture and Texture Parameters Research]]> qualities of potato tubers not only are beneficial to the subdivision of processing quality traits and accurately locate purpose of potato, but also assist breeders screening new varieties, and accelerate the development of potato products.【Method】Potato cultivated varieties were selected as the research samples. Puncture, TPA compression and shear methods were chosen to analyze the texture parameters. These included puncture distance, puncture initial force, puncture speed, compression deformation, compression speed, compression interval time, compression initial force, shear initial force and speed. The texture indexes of eight varieties were measured under the optimal texture analyzer parameters setting, then the correlation among the texture parameters and the evaluation of optimal texture parameters were analyzed. 【Result】Optimal parameters of fresh tuber puncture: cylindrical metal probe (TMS 2 mm Steel), 2 mm puncture distance and, 2.5 N initial force, 50 mm·min-1 detection speed. The optimal test factors of TPA compression (fresh/steamed): the cylinder sample for fresh and steamed tubers both ranged in the diameter and height from 10 mm to 15 mm, no significant difference was examined among three probe selection in the fresh tubers. Cylindrical aluminum probe (TMS 36.0 mm Aluminum Cylinder) was the optimal type for steamed tubers probe. The optimal parameters (fresh/steamed): 50% and 60% deformation, 60 mm·min-1 and 80 mm·min-1 detection speed, 6 s and 10 s interval time, both 0.7 N initial force. The optimal shear parameters (fresh/steamed): the length, width and height of the cuboid sample were 30 mm, 15 mm, and 10 mm, respectively. The probe type was light single knife probe (TMS Perspex Knife Edge), with both 60 mm·min-1 detection speed, and 1 N and 0.5 N initial force. They’re existed significant correlation between springiness and the peel crispness, no significant correlation among the other texture parameters of TPA compression and shear. They’re existed significant positive correlation among puncture, TPA compression and shear texture parameters (0.410-0.959) in fresh tubers. There also existed significant positive correlation between TPA compression and shear texture parameters (0.441-0.952) in steamed tubers. 【Conclusion】Puncture, TPA compression and shear methods were suitable for the samples evaluation of the quality of fresh tubers. The indexes of peel hardness, peel brittleness, TPA hardness, cohesiveness, chewiness, shear hardness can be chosen as important parameters to compare differences of texture. TPA compression and shear methods were suitable for the sample’s evaluation of the quality of steamed tubers. The indexes of TPA hardness, adhesiveness, cohesiveness, springiness, chewiness, shear hardness can be chosen as important parameters to compare differences of texture.


]]> <![CDATA[Genome-wide Association Study of Yield Component Traits in Upland Cotton (<em>Gossypium hirsutum</em> L.)]]> 】The loci, elite alleles and candidate genes associated with yield component traits, such as boll weight, lint percentage, number of bolls per plant and seed index, were explored using a genome-wide association analysis (GWAS), which provided a theoretical reference for the molecular breeding of cotton yield.【Method】The GWAS based on a mixed linear model was performed on 408 upland cotton accessions grown in six different environments using the Cotton SNP 80K chip for the four yield component traits, and the significant SNP loci (SNPs) and elite allele were also detected. Finally, on the basis of the gene expression levels of the transcriptome, candidate genes related to the target traits were mined within a 1 Mb genome range of the flanking sequences of the significant SNPs. 【Result】The four yield component traits showed wide phenotypic variations in different environments, with the maximum coefficient of variation for number of bolls per plant being 16.67%-22.66%. The heritability of each trait was between 48.4% and 92.2%. The correlations among traits were significant or highly significant, except between boll weight and lint percentage. A total of 23 significant SNPs distributed in seven different genomic regions associated with the four traits were identified across the 408 cotton accessions in the BLUP. The numbers of loci associated with boll weight, lint percentage, number of bolls per plant and seed index were 5, 1, 9 and 8, respectively, and three loci (TM21094, TM21102, and TM57382) were associated with multiple target traits simultaneously. Seven elite allele types, TM21099(TT), TM57382(GG), TM78920(CC), TM53448(TT), TM59015(AA), TM43412(GG) and TM69770(AA), were identified. A total of 158 candidate genes potentially related to yield formation were selected through an analysis of gene expression patterns in RNA-Seq data. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses indicated that the functions and metabolic pathways of most genes were varied.【Conclusion】In this study, 23 significant SNPs associated with four yield component traits were identified across 408 cotton accessions, and 158 candidate genes were predicted using RNA-Seq.


]]> <![CDATA[Synergistic Effects of Organic Carbon and Nitrogen Contents in Water-Stable Aggregates, and Microbial Biomass on Crop Yield Under Long-term Straw Combined Chemical Fertilizers Application]]> Objective】The effects of long-term straw combined application of chemical fertilizers on the content of aggregates, distributions of aggregate-associated organic carbon and nitrogen, and soil microbial biomass were studied to reveal the promotion of soil fertility and productivity. 【Method】Soil samples were collected from a 40-year long-term experiment. The research is conducted with 4 treatments：pure chemical fertilizer（NP），straw with chemical fertilizer (S+NP), straw with 1/2 chemical fertilizer (S+1/2NP), and straw with 1/4 chemical fertilizer (S+1/4NP), and the straw is returned with the amount of 3 000 kg·hm-2, chemical fertilizer NP is pure N 150 kg·hm-2，P2O5 150 kg·hm-2 conducted. All soils samples were separated into four aggregate-size classes (>2 mm, 0.25-2 mm, 0.053-0.25 mm and <0.053 mm) by wet sieving. Organic carbon and total nitrogen contents of aggregates and soil microbial biomass content were measured. 【Result】(1) Long-term application of chemical fertilizers with straw reduced soil bulk density while improved the stability of aggregates. Compared with NP, the bulk density of S+NP decreased by 4.7%, while the proportion of aggregates >2 mm in size，the average weight diameter (MWD) and geometric weight diameter (GWD) increased by 254.4%, 76.5% and 91.3%, respectively. (2) In the three chemical fertilizers combined with straw return, the percentage of aggregates >2 mm, MWD and GWD in the S+NP and S+1/2NP were significantly increased by 49.1%-52.4%，19.43%-22.4% 和24.2%-33.3% compared with S+1/4NP, respectively. (3) Compared with NP, S+NP, S+1/2NP and S+1/4NP increased the contribution rate of aggregates >2 mm and >0.25 mm to SOC and total nitrogen, and significantly improved the SOC, SMBC and SMBN content in bulk soil. Among them, the SOC content was highest in S+NP, which was 6.3% and 12.6% higher than that in S+1/2NP and S+1/4NP, respectively. (4) The yield was showed that S+NP>NP>S+1/2NP>S+1/4NP, and S+NP increased wheat yield by 5.83%-83.6% compared with other treatments. (5) Positive correlation was revealed between soil aggregate stability, carbon and nitrogen content and crop yield, and >2 mm aggregate content, MWD and GWD are significantly or extremely significant with the total soil SOC, SMBC content and wheat yield, respectively.【Conclusion】In the dark brown soil area, long-term straw returning and fertilizer application of 150 kg·hm-2 and P2O5 150 kg·hm-2 can improve aggregate stability, soil organic carbon content, microbial biomass and yield, and maximize the To achieve the synergistic effect of soil structure improvement, fertility improvement and crop yield increase.


]]> <![CDATA[Effects of Combined Application of Organic Manure and Chemical Fertilizer on Water and Nitrogen Use Efficiency of Cotton Under Water Deficit]]> 】To explore the effects of combined application of organic manure and chemical fertilizer on water and nitrogen use efficiency and yield of cotton under different water conditions, so as to provide a theoretical basis for the rational use of organic fertilizer in the cotton area of Hexi corridor.【Method】Field experiments were carried out from 2020 to 2021. The experiment was designed by split block, the main plot treatment consisted of full irrigation (W1) and deficit irrigation(W2), the split-plot treatment was composed of five fertilizer treatments: no fertilizer (CK), single application of chemical fertilizer (CF), 25% organic manure with 75% chemical fertilizer (OF1), 50% organic manure with 50% chemical fertilizer (OF2) and 75% organic manure with 25% chemical fertilizer (OF3), the nutrient content of each fertilization treatment was equal. The effects of fertilization under different water conditions on soil water content, periodical evapotranspiration, dry matter accumulation, nitrogen accumulation, transport and distribution, water and nitrogen use efficiency, seed cotton yield and economic benefits were analyzed. 【Result】The seed cotton yield , water and nitrogen utilization characteristics of cotton were significantly affected by different water and fertilizer treatments and interactions. Soil water content, total evapotranspiration, dry matter accumulation, total nitrogen uptake and seed cotton yield decreased significantly, while water use efficiency increased significantly under deficit irrigation. The suitable combined application of organic manure and chemical fertilizer treatment can increase the soil water content of 0-40 cm, reduce the evapotranspiration at seedling stage and budding stage, while increase the evapotranspiration at flower-boll stage, increase dry matter and nitrogen accumulation and promote distribution to reproductive organs. Under the condition of full irrigation, the yield of the treatment of 25% organic manure was the highest in all fertilization treatments, with an average increase of 10.5% over single application of chemical fertilizer in two years, there was no significant difference between 50% organic manure and single application of chemical fertilizer, while the treatment of 75% organic manure was significantly lower than single application of chemical fertilizer. The treatment of 25% organic manure had the highest water and nitrogen use efficiency in each fertilization treatment, in which water use efficiency, nitrogen use efficiency and nitrogen agronomic use efficiency were 8.9%, 14.3% and 28.9% higher than single application of chemical fertilizer respectively. Under the condition of deficit irrigation, the seed cotton yield of the combined application of organic manure and chemical fertilizer treatments were higher than that of single application of chemical fertilizer, among which 50% organic manure was the highest, and the average seed cotton yield of two years was 12.9% higher than that of single application of chemical fertilizer, meanwhile, the treatment of 50% organic manure also had the highest water and nitrogen use efficiency, in which the water use efficiency, nitrogen use efficiency and nitrogen agronomic use efficiency were 14.8%, 35.5% and 31.6% higher than that of single application of chemical fertilizer respectively.【Conclusion】The appropriate proportion of combined application of organic manure and chemical fertilizer can coordinate the supply and demand relationship of soil and crop for water and nutrients, and improve the seed cotton yield and the water and nitrogen use efficiency. Considering yield, water and nitrogen use efficiency and economic benefits, the treatment of 25% organic manure was the suitable mode of organic fertilizer application in Hexi corridor.

]]> <![CDATA[Geographical Origin Tracing of Fuji Apple Based on Mineral Element Fingerprinting Technology]]> 】 To explore the geographical characteristics of the mineral element content in Fuji apple peel and the feasibility of geographical origin tracing. To screen out effective discriminant indicators by combining multivariate statistical analysis, establish an origin tracing model, and realize Fuji apple geographical origin identification. 【Methods】 The 124 Fuji apple samples collected from the two main production areas in China, namely, the Bohai Bay production area and the Loess Plateau production area, were taken as the research object. Inductively coupled plasma-mass spectrometry (ICP-MS) was applied to determine the contents of 31 mineral elements in the peel, including macroelements Sodium (Na), Magnesium (Mg), Potassium (K), and Calcium (Ca); microelements Vanadium (V), Chromium (Cr), Manganese (Mn), Iron (Fe), Cobalt (Co), Nickel (Ni), Copper (Cu), Zinc (Zn), Arsenic (As), Molybdenum (Mo), Cadmium (Cd), Antimony (Sb), Barium (Ba), Lead (Pb), and Uranium (U); rare earth elements Yttrium (Y), Lanthanum (La), Caesium (Ce), Praseodymium (Pr), Neodymium (Nd), Samarium (Sm), Europium (Eu), Gadolinium (Gd), Terbium (Tb), Dysprosium (Dy), Holmium (Ho), and Erbium (Er). The independent samples t-test, principal component analysis (PCA), linear discriminant analysis, and orthogonal partial least squares discriminant analysis were conducted for geographical origin tracing. 【Results】 The mineral elements Mg, Ca, Na, Fe, Mn, Cu, Ba, Ni, Nd, Pb, V, Ce, Pr, La, Dy, U, Ho and Co in the peel samples from the Bohai Bay and Loess Plateau production areas were significantly different ( P<0.05). The results of the PCA showed that the cumulative variance contribution rate of the 12 extracted principal components was 81%, which allowed the preliminary clustering of the samples from the two major production areas. After linear discriminant analysis, 10 mineral elements (Mg, Ca, Cr, Mn, Fe, Ni, Gd, Tb, Dy, U) were screened as ideal indicators to discriminate the geographical origin of Fuji apples in the two major production areas. The discriminant rate of the established discriminant model for the original whole was 92%, and the cross-validation discriminant rate was 89.5%. The orthogonal partial least squares discriminant analysis showed that five rare earth elements, Co, Ba, Ho, Dy and Pr, play a key role in the sample classification, and the accuracy of origin identification by the model could reach 98%, which realized the origin traceability of Fuji apples in the two production areas. 【Conclusion】 The peel of Fuji apple can be used as an effective site for origin tracing. The contents of rare earth elements Dy, Ho, Pr, Gd and Tb are important indicators for the geographical origin tracing of Fuji apples. This study can provide a theoretical basis and technical support for Fuji apple origin tracing.


]]> <![CDATA[Transcriptome <span>A</span>nalysis <span>R</span>eveals the <span>D</span>ifferential <span>E</span>xpression of <span>G</span>enes <span>R</span>elated to <span>S</span>tarch <span>A</span>ccumulation in <span>C</span>hloroplast of <span>L</span>ea<span>f</span> <span>with D</span>ifferent <span>A</span>ge<span>s</span> in Pinot Noir <span>G</span>rape (<i>Vitis vinifera</i> L.) ]]> 】The accumulation of starch in chloroplast of grape leaves increased with leaf maturation, but the related molecular mechanism has not been reported. We screened the potential related genes in order to clarify the molecular regulation mechanism of starch accumulation in chloroplast of grape leaves with different leaf ages.【Method】 Two years old ‘Pinot Noir’ grapes were used as plant materials to investigate the dynamic changes of starch accumulation in chloroplast of leaves with different ages. The RNA sequencing technology was used to characterize the differently expressed genes (DEGs) involved in starch and sucrose metabolism in leaves with different ages.The expression levels of several key candidate genes were detected.by using real-time quantitative qPCR.【Result】The starch grains in NL (undeveloped leaves) were smallest in volume and lowest in number compared to these in GL (growing leaves) and ML (mature leaves). With the increase of leaf ages, the volume and amount of starch grains in GL and ML also increased. A total of 58.57 GB valid data was obtained by RNA-sequencing. Differentially expressed genes mainly involved in starch and sucrose metabolism pathway for the leaves with different ages. the genes involved in the process of sucrose conversion into starch synthesis precursor adenosine diphosphate glucose (ADP) showed up-regulated expression level with the increase of leaf ages, these related genes included CELL WALL INVERTASE (CWINV), PHOSPHOGLUCOMUTASE (PGM), and ADP-glucose pyrophosphorylase (AGPase). The genes involved in starch synthesis and hydrolysis also presented up-regulated expression level with the increase of leaf ages, including SOLUBLE STARCH SYNTHASE (SSⅠ), STARCH BRANCHING ENZYME (SBE), α-AMYLASE (AMY), and β-AMYLASE (BAM). AGPase, SSⅠ, and SBE played an important role in synthesis of amylopectin with semi-crystalline structure.【Conclusion】With the increase of leaf ages, starch accumulation in chloroplast also increased. AGPase, SSⅠ and SBE genes could be the key genes involved in the regulation of starch accumulation in chloroplast of grape leaves.

]]> <![CDATA[Genome-Wide Identification of NAC Family and Screening of Its Members Related to Prickle Development in <em>Rosa chinensis</em> Old Blush]]> 】This study was designed to identify the NAC gene family in Rosa chinensis ‘Old Blush’, analyze the sequences characteristics and expression pattern of RcNACs to reveal the biological functions of RcNACs. It also provides an important foundation to explore the role of RcNACs in prickles. 【Method】The BLATP and HMMER search were conducted to identify NAC proteins in Rosa chinensis ‘Old Blush’ using the sequences of NAC proteins of Arabidopsis. Physical and chemical properties, subcellular location, structure and phylogenetic relationship of each gene were further analyzed. Based on the released transcriptome data, the expression characteristics of RcNACs in different tissues and organs and under different stress conditions were analyzed. What’s more, the technology of RNA-seq was used to screen RcNAC genes that might be related to the prickle development. 【Result】In this study, we identified and characterized 116 NAC genes from Rosa chinensis ‘Old Blush’ genome. These RcNACs genes encoded proteins containing 69 to 713 amino acids, with the theoretical isoelectric points ranging from 4.43 to 9.54 and the molecular weight ranging from 7.87 to 79.99kD. The prediction of subcellular localization showed that 81 RcNACs were located in the nucleus. Moreover, RcNACs were unevenly distributed on 7 chromosomes. According to phylogenetic relationships, AtNACs, OsNACs and RcNACs were clustered into 21 groups. These 116 RcNACs were differentially expressed in various tissues and organs, and the expression levels of 31 members changed in response to abiotic and biotic stresses. Furthermore, in the RNA-seq data of prickles, 53 RcNACs were detected, of which 26 members were differentially expressed genes. 【Conclusion】This study demonstrated that RcNACs were involved in the regulation of plant development and stress responses. Some members might be involved in the processes of prickle cell proliferation, secondary cell wall biosynthesis and programmed cell death, which could be selected as candidate genes related with prickle development for further study.


]]> <![CDATA[Optimized Management Mode for Disease and Nutrient During the Entire Fruit Development Improves the Postharvest Storability of Longan Fruit]]> Objective】To obtain an optimized preharvest management mode to improve the longan fruit storability, the effects of disease control and nutrient management during fruit development on the characteristic quality and storability of longan fruit were explored. 【Method】A field-based orthogonal trial (12 (4×33)) was conducted with 12 combinations (labeled as BR1-BR12) using the cultivar Shixia as material, among which BR1 was the control (CK). Disease control (DCP), fertilization type (FT) and hormone regulation (HR) were used as factor A (FacA), factor B (FacB) and factor C (FacC) respectively. The fruit quality and mineral nutrient contents were determined at harvest time, and the storage effects for the fruit of 12 treatments stored at 5℃ were also observed regularly to screen the factors and levels with significant optimization effects.【Result】(1) Descriptive statistical analysis showed that the variation coefficients of 11 fruit quality and 20 mineral nutrition (in pericarp and aril) indexes ranged from 2.19% to 49.50% and from 5.14% to 77.43% respectively. Except for the organoleptic trait indicators including CDFS (cleanliness degree of fruit surface), RPTC (rust powder in the turtle cracks on the fruit surface) and ACD (aril crispy degree), the other indexes showed significant differences between treatments (P<0.01). (2) With the prolonging of the storage period, the MFR (mouldy fruit rate), EBI (endocarp browning index), ABI (aril breakdown index) of each treatment fruit increased, and the EFR (edible fruit rate) and storability decreased, and the difference between treatments was extremely significant (P<0.01). Moreover, the clustering results showed that BR11 and BR12 had the best storage effect with the lowest EBS (endocarp browning score), ABS (aril breakdown score) and MFRS (score of mildew fruit rate), and the highest EFRS (score of edible fruit rate) and CSES (score of comprehensive storability throughout the entire storage), and their storage life was about 40 days and about 15 days longer than the control (BR1). On the contrary, BR1and BR2 had the worst storability with about 25 days of storage life. (3) Correlation analysis showed that disease control (facA) was closely associated with EBS, ABS, MFRS, EFRS and CSES during the fruit storage (P<0.01), b* value of fruit surface (FSb*)  and ACD, total Zn and Mn contents in pericarp were closely related to fruit storage effects (P<0.01). Besides these, the contents of K, Ca, Mg mainly affected the SFM (single fruit mass), EPRF (edible portions rate in a fruit), TSS (content of total soluble solid substance) and RPTC of fruit, and the contents of Zn, Mn, B mainly affected CDFS and RPTC. (4) The estimated marginal means of each level of trial factors showed that, compared with no disease control (1-DCK) and young fruit stage (2-YS), disease control during the entire fruit period (4-EP) and expansion stage (3-ES) could significantly improve the FSb*,FSC* (C* value of fruit surface, P<0.05) and CDFS (P<0.01), reduce the EBS, ABS and MFR, and ultimately improve the EFRS and CSES. Among the 4 kinds of disease control methods, the control effect of 4-EP was the best (P<0.01). Full nutrition fertilizer (3-FF) significantly improved the ACD, CDFS and CSES and reduced the MFRS, otherwise, hormone regulation (HR) did no obvious effect.【Conclusion】Scientific and reasonable disease control and nutrient management before harvest can significantly improve the characteristic quality and storability of longan fruit. It is recommended to optimize the comprehensive management mode during fruit development as “disease control throughout the entire fruit period + full nutrient fertilization”.


]]> <![CDATA[Eating Quality Evaluation of Lamb in Different Postmortem Phases Based on Consumers’ Sensory Preferences]]> 】The eating quality of lamb in pre-rigor, rigor mortis and post-rigor phases was investigated using consumers’ sensory evaluation to understand the differences of eating quality characteristics of lamb in different postmortem phases under instant boiling, roasting, boiling and stir-frying conditions, which was expected to provide reference for lamb quality evaluation and high-quality meat production.【Method】The oyster cut, short loin, knuckle and silverside in per-rigor, rigor mortis and post-rigor phases were obtained from Small-tail Han sheep (male, 8 months old). The sensory attributes (including tenderness, juiciness, flavor and overall liking) of lamb after instant boiling, roasting, boiling and stir-frying were evaluated by consumers. The MQ4 (Meat Quality, 4 variables) equation and the grades boundaries were determined by linear discriminant analysis, which were used to analyze the preference score and eating quality grade of lamb.【Result】After instant boiling, the short loin and silverside in pre-rigor had higher tenderness, flavor and MQ4 scores than those in rigor mortis and post-rigor phases (P＜0.05), and there was no significant difference in consumers’ scores of oyster cut and knuckle in different postmortem phases (P＞0.05). After roasting, the oyster cut in per-rigor and the silverside in post-rigor phase had higher tenderness, juiciness, overall liking and MQ4 scores than those in rigor mortis (P＜0.05), and there was no significant difference in consumers’ scores of short loin and knuckle in different postmortem phases (P＞0.05). After boiling, the juiciness and overall liking scores of knuckle in post-rigor were higher than those in per-rigor and rigor mortis phases (P＜0.05), and there was no significant difference in consumers’ scores of oyster cut, short loin and silverside in different postmortem phases (P＞0.05). After stir-frying, the tenderness, overall liking and MQ4 scores of oyster cut in pre-rigor and post-rigor were higher than those in rigor mortis, and the tenderness, flavor, overall liking and MQ4 scores of short loin in pre-rigor were higher than those in rigor mortis and post-rigor (P＜0.05). There was no significant difference in consumers’ scores of knuckle and silverside in different postmortem phases (P＞0.05). The premium quality (4star) and good quality (5star) samples were higher in pre-rigor (5star: 0%-8.33%; 4star: 47.83%-72.22%) and post-rigor (5star: 0%-8.70%: 4star: 52.78%-58.33%) There were no unsatisfactory quality (2star) samples in pre-rigor and post-rigor phases, while 4.17% and 4.35% of the samples in rigor mortis were 2star after roasting and boiling respectively. 【Conclusion】In general, pre-rigor and post-rigor lamb had a superior eating quality to rigor mortis lamb based on consumers’ sensory evaluation, and pre-rigor and post-rigor lamb were preferred by Chinese consumers.


]]> <![CDATA[Cry1Ac Protein Content Responses to Alternating High Temperature Regime and Drought and Physiological Mechanism in Bt Cotton]]> ive】This study was conducted to investigate the effect of alternating high temperature and drought on the content of Cry1Ac protein in Bt cotton and the underlying physiological mechanism to provide a reference for the safe and stable utilization of insect resistance of Bt cotton in production.【Method】The conventional cultivar Sikang 1 (SK-1) and hybrid cultivar Sikang 3 (SK-3) were used in 2019 and 2020 in experimentally controlled greenhouse, Yangzhou University. From 7：00 am to 7：00 pm two high-temperature treatments [34℃ (A1) and 38℃ (A2)] were imposed on cotton plants, followed by an optimum temperature 28℃ during the remaining night hours. There were two treatments for soil moisture content, which were 50% (B1) and 60% (B2) field capacity. The treatment with 32℃/28℃ and 75% field capacity was set as the control (CK). The leaf Cry1Ac protein content and its physiological mechanism were detected on 4, 7, and 10 days after stress (DAS), respectively.【Result】Compared with CK, the Cry1Ac protein content all decreased under stresses of high temperature and drought, and with the extension of the stress time, greater decrease was observed. The extent of decline for A1B2 was the smallest, followed by A1B1, and A2B1 and A2B1 were the largest. The Cry1Ac protein content for A1B2 was significantly lower than CK after 7 DAS, while significant differences between A1B1, A2B2, A2B2 and CK were detected after 4 DAS. The Bt gene expression level, soluble protein (SP), free amino acid (aa) contents, nitrate reductase (NR), the glutamic pyruvic transaminase (GPT), glutamic oxaloacetate transaminase (GOT), glutamine synthetase (GS) and glutamate synthase (GOGAT) activities showed a downward trend. While the tannin content, the activities of protease and peptidase showed an upward trend. The correlation analysis and path analysis showed SP, aa, NR, GPT, GOT, GS, GOGAT were positively correlated with Cry1Ac protein content. The tannin content, the activities of protease and peptidase were negatively correlated with Cry1Ac protein content. NR, GPT and GS could be key indices for the Cry1Ac protein content.【Conclusion】The interaction of high temperature and drought resulted in the decrease of Cry1Ac protein content in Bt cotton, with greater decrease observed as the stress extended. There was no significant difference between the treatment with 34℃/28℃ and 60% field capacity and CK in 7-10 DAS. The extent of reduction decreased and the period was delayed. NR, GPT and GS could be key indices for the Cry1Ac protein content.


]]> <![CDATA[Effects of Different Nitrogen Gradients on Yield and Nitrogen Uptake of Hybrid Seed Maize in Northwest China]]> -2, respectively. 【Result】The accumulation of parental biomass of hybrid maize seed production increased with the increase of nitrogen gradients. The yield of maize seed production increased at first and then remained stable with the increase of nitrogen gradients. N240 treatment achieved higher yield, nitrogen use efficiency and grain nitrogen concentration at the same time, which were consistent in the two years. The yield of N168 treatment was higher than that of N240 treatment in the second year, but the nitrogen concentration was lower than that of N240 treatment. The nitrogen concentration of the whole plant of female parent straw and male parent was higher in high nitrogen gradient treatment than that in low nitrogen gradient treatment; the critical nitrogen concentration of maximum biomass of female parent at filling stage was 15.08 g·kg-1, and there was a linear correlation between female parent biomass and nitrogen concentration at harvest stage. The post-silking biomass of each topdressing nitrogen fertilizer treatment was higher than that of pre-silking stages in two years, and increased with the increase of nitrogen gradients. The change rule of post-silking nitrogen uptake ratio with nitrogen gradients was consistent with the biomass. There was no significant difference in yield level, biomass accumulation, and nitrogen uptake between N320 treatment and N240 treatment. Under the premise of comprehensive consideration of yield and hybrid seed quality, N240 could be regarded as the recommended nitrogen application rate for hybrid maize seed production in this region. 【Conclusion】The optimal nitrogen application rate can increase yield and nitrogen use efficiency by regulating the ratio of nitrogen uptake for maize parents in pre- and post-silking in seed maize production. This study revealed that optimizing nitrogen application rate to stabilize nitrogen uptake in the pre-silking stage and ensure nitrogen supply after anthesis was the key to achieve high yield and nitrogen use efficiency of seed maize, and provided a theoretical basis for sustainable production of hybrid seed maize.


]]> <![CDATA[Crop Classification with Time Series Remote Sensing based on Bi-LSTM Model]]> Objective】Timely and accurate crop classification mapping is an important basis for agricultural situation monitoring. With the significant increase in spatial and temporal resolution of satellite remote sensing data acquisition, crop classification and early identification based on intensive time series remote sensing data have become possible. Meanwhile, the rapid development of machine learning methods with deep learning has provided new technical support for crop remote sensing classification.【Method】In this paper, we take the Yellow River Delta region as an example and construct a time-series NDVI dataset using Sentinel-2 year-round available satellite images as the data source. Based on a recurrent neural network architecture, a Bidirectional Long Short-Term Memory (Bi-LSTM) network model is built to explore its potential application in crop classification using its feature learning capability for structured time series data. 【Result】Winter-wheat-summer-maize is the main crop cultivation pattern in the region, and the overall accuracy of the Bi-LSTM model reached 90.9% with a Kappa coefficient of 0.892. Crop accuracy improves with the increase of time series data length. The accuracy of crops such as winter-wheat and rice will improve significantly after the emergence of unique characteristics. Crops such as cotton and spring-maize require complete growth sequences to ensure classification accuracy. 【Conclusion】Structured feature information embedded in satellite image time series can effectively reduce crop spectral confusion at specific time periods. The Bi-LSTM model is able to consider both forward and backward temporal state information and can learn the spectral change characteristics of crops, which is excellent in the identification of confusing crops such as rice, cotton and spring corn. By testing the effect of different time series length on crop classification, the earliest identifiable time of typical crops was obtained for early mapping of crops under certain mapping accuracy. In addition, the deep learning model can effectively capture the variation trend on the sample in general, and shows better generalization ability and robustness in the crop multi-classification task. This study provides a feasible idea for regional crop mapping with high accuracy by integrating deep learning and remote sensing time series.


]]> <![CDATA[Straw mulching from autumn fallow and reducing nitrogen application improved grain yield, water and nitrogen use efficiencies of dryland winter wheat by optimizing root distribution]]> province from 2016 to 2018. The spilt plot design was employed with main plot of maize straw mulching (mulching from autumn fallow to wheat harvesting: SM) and no mulching (NM), and sub-plot of different nitrogen application rates (N0: 0); reducing nitrogen rate (RN): 120 kg N·hm-2 and conventional nitrogen rate (CN): 180 kg N·hm-2). Soil moisture, root length, root distribution, wheat yield, water consumption (ET), water and nitrogen use efficiencies were investigated. 【Result】Compared with NM, SM significantly increased the soil water content in 0―-10 cm and 10―-20 cm layers from sowing to booting stage and the soil water storage in 0―-100 cm layer at sowing and jointing, and the soil water retention effect of straw mulching lasted until booting and anthesis stage. SM also promoted the wheat root growth at jointing and anthesis stage with higher root diameter and significantly higher root length density in 0―-10 cm layer. The mean values of total ET, WUE (water use efficiency), nitrogen accumulation amount of wheat plant, nitrogen accumulation rate from sowing to jointing, nitrogen accumulation rate from jointing to anthesis, nitrogen use efficiency for grain production (NUEg), agronomic efficiency of nitrogen fertilizer (AEN), nitrogen fertilizer partial factor productivity (NPFP) and wheat yield increased by 11.4%, 71.8%, 73.1%, 119.0%, 100.0%, 3.6%, 264.7%, 78.2% than that of NM, respectively, and the recovery efficiency of nitrogen fertilizer (REN) in SM increased by 44.4 percentage points compared with NM. Wheat yield under SM increased by 92.9% because of the significantly increased average spike number (31.8%) and grains per spike (44.4%). The effect of straw mulching was greater than that of nitrogen application. Compared with CN, RN did not significantly decrease the wheat root length density, ET, WUE and wheat yield. Combining with SM, RN significantly improved the NUEg, physiological efficiency of nitrogen (PEN), AEN, NPFP and REN. 【Conclusion】Straw mulching from autumn fallow improved soil water content and storage and optimized root distribution in 0―-10 cm layer with higher root length density and root diameter, thus to increase the nitrogen absorption and utilization, wheat yield and the utilization of water and fertilizer. Straw mulching combined with 120 kg N·hm-2 was a high yield cultivation mode with reducing nitrogen application and high water and nitrogen use efficiency for dryland winter wheat in Sichuan, China.


]]> <![CDATA[Effects of Irrigation Amount on The Berry Development and Aroma Components Accumulation of Shine Muscat Grape in Root-restricted Cultivation]]> 】The effects of different irrigation amounts on grape berry quality, aroma component accumulation, and the expression level of aroma compounds biosynthetic genes were studied to determine the relationship between irrigation patterns and sensory quality of table grapes and provide a reference for choosing the optimal irrigation amount in root-restricted cultivation. 【Method】The table grape cultivar Shine Muscat was used as the test material, the control group CK, the mild water deficit group DI-1, and the severe water deficit group DI-2 were set up to systematically compare the effect of different irrigation amounts on the morphological indicators, appearance color indicators, aroma components, and expression levels of terpene biosynthetic genes of grape berries. 【Result】Irrigation amount can affect the morphological and texture characteristics of grape berries. Comparing other treatments, the longitudinal diameter of grape berries at harvest time was not significantly affected by irrigation amount, while the horizontal diameter and single berry weight of grape berries in deficit irrigation group were significantly reduced. The firmness of grape pulp also decreased under the influence of deficit irrigation, especially in DI-2 group, of which the pulp firmness was significantly lower than that of other treatment groups. Meanwhile, the glucose content in the grape berries of the deficit irrigation group DI-1 and DI-2 was significantly higher than that in the control treatment, and the fructose content in the severe deficit irrigation group DI-2 was significantly higher than that in other treatments. Mild deficit irrigation of DI-1 exerted little effect on the content of total soluble solids and titratable acid in grape berries. The contents of chlorophyll and carotenoids in grape skins were decreased under the deficit irrigation treatment, but the ratio of the chlorophyll content to carotenoids content in the skins of the DI-2 group was the highest. Additionally, the amount of irrigation also affected the accumulation of aroma components in grape berries. The terpenes compounds, such as limonene, phellandrene, α-pinene, γ-terpinene, (E)-β-ocimene, terpinolene, (E)-furanoxylinalool, linalool, dihydrolinalool, α-terpineol, citronellol, nerol, and geraniol, reached the highest content in the berries of the DI-1 group, followed by the content of terpenes in the DI-2 group, and the lowest in the control group. As for esters, the total content of those compounds in the DI-1 group was the highest, followed by the control group, and the content of the DI-2 group was the lowest. From the total amount of aldehydes, the content in the DI-1 group were significantly lower than those in the control group and DI-2 group. From the total amount of higher alcohols, the content of DI-1 group was the highest, followed by DI-2 group, and the control group was the lowest. There were differences in the expression patterns of terpene biosynthesis-related genes under different irrigation conditions. The expression of VvDXS1, VvDXS2, VvDXR, VvDHR, VvPNLinNer1, VvCSLinNer, VvGwbOci, VvCSbOci and VvGwGer were up-regulated in response to water deficit.【Conclusion】According to the accumulation of aroma components and the comprehensive score of sensory quality, mild water deficit (60%—70% of the maximum water holding capacity in the field) can better promote the formation of aroma quality of Shine Muscat grape berries and improve their commercial value.


]]> <![CDATA[Identification and Functional Analysis of StSCD Family in <i>Setosphaeria turcica </i> #br#]]> 】Scytalone dehydratase (SCD) is a key enzyme in melanin synthesis. The purpose of this paper is to identify the StSCD gene family of Setosphaeria turcica, and to analyze the differences in the expression of StSCD gene family during the appressorium development of S. turcica and the effect of SCD inhibitors on melanin synthesis, laying a foundation for further research on the important role of the StSCD gene family in melanin synthesis and appressorium development. 【Method】Using the whole genome data of the wild-type strain 01-23 of S. turcica, the complete sequence of the StSCD gene family was obtained, and the sequences were compared with the SCD genes of Cochlibolus heterostrophus, Pyricularia oryzae, Colletotrichum lagenaria and other fungi. Collected materials from different appressorium  developmental stages for RT-PCR analysis to obtain the expression levels of different StSCDs genes at different stages, so as to determine the important dehydratase genes closely related to pathogen infection and appressorium melanization. Carpropamid, an inhibitor of SCD, was used to treat S. turcica, and the colony growth rate, melanin production and appressorium turgor pressure were measured, so as to determine the important function of SCD in appressorium development. 【Result】Four StSCD genes were found by searching the whole genome of S. turcica, the encoded protein of them has SCD conserved domain and conserved catalytic and substrate binding amino acid residues.  StSCD3 protein had high homology with the functionally redundant SCD2 protein of Botrytis cinerea, and StSCD4 has high homology with SCD proteins involved in melanin synthesis in pathogenic fungi. By analyzing the expression levels of StSCD genes at different stages during the growth and development of the pathogen, it was found that the expression levels of four StSCD genes were all up-regulated in the appressorium stage, and the expression levels of StSCD3 and StSCD4 were particularly up-regulated. The expression levels of StSCDs 6 h after appressorium formation were significantly decreased, and the expression levels of StSCD3 and StSCD4 were higher during the whole period of appressorium induction. The melanin synthesis was blocked and the appressorium pressure was significantly reduced after carpropamid treatment. 【Conclusion】There are four StSCD genes in S. turcica. It is speculated that StSCD4 is involved in the synthesis of DHN melanin, and then affects the accumulation of appressorium. The above research results lay a foundation for further elucidating the gene function of StSCDs of S. turcica.


]]> <![CDATA[Effects of ‘Good Quality Standard’ Rice System on Soil Environment of Paddy Field #br#]]> 】The self-developed rice good quality standard system (named as GQS) has been implemented in production, and the rice yield, quality and soil environment were evaluated, providing scientific basis for the reasonable design and timely adjustment of GQS.【Method】Based on the pilot area of fixed-point and GQS, which was carried out continuously for 1-5 years in rice growing areas of Jiangsu and Shanghai, the conventional rice cultivation system (CCS) was taken as control. The rice samples and soil samples were collected for the comprehensive evaluation and analysis of rice yield safety and quality, safety, soil fertility, soil enzyme activity and soil microbial diversity.【Result】Compared with the CCS, the application amount of nitrogen fertilizer was reduced by 46.8% in the optimal standard system, and organic fertilizer, EM bacteria agent, foliar fertilizer and zinc fertilizer were added instead. The application of pesticides with biological agents as the core, synergistic use of low toxicity and low residue chemical pesticides advantages. Under the premise of ensuring rice yield, quality safety, the application of GQS significantly increased soil total nitrogen and organic matter contents. The comprehensive score of soil fertility of the GQS was higher than that of the CCS after 1 to 4 years of continuous implementation, but the comprehensive score of soil fertility of the GQS after 5 years of continuous implementation was lower than that of the CCS. The activities of urease, dehydrogenase and sucrase in the optimal system were higher than those in the CCS. The diversity and abundance of bacterial community were increased in the paddy soil with the application of GQS. Bacteroidetes and Chloroflexi showed repeated changes in the increasing ratio of soil bacterial richness after the first year and the second consecutive year of application of the GQS. Terrimonas and Flavobacterium are the dominant genera. The results of correlation analysis showed that the abundance of Bacteroidetes and Chloroflexi were positively correlated with pH fertility index and total P fertility index after the implementation of the GQS for 1 year. The results showed that the abundance of Bacteroidetes and Chloroflexi were positively correlated with the change of pH fertility index. In addition, there was a positive correlation between the abundance of Bacteroidetes and Chloroflexi and soil dehydrogenase activity.【Conclusion】Under the premise of ensuring rice yield and quality safety, The application of GQS was helpful for the restoration of rice soil fertility by effectively improving the soil quality and the diversity of soil bacterial community.


]]> <![CDATA[Effects of Maize Straw and Root Residues Added <span>on </span>Microbial Residue Carbon and Nitrogen <span>in</span> Different Fertility Levels of Black Soil #br#]]> 】Crop straw and root residues are the significance sources of soil organic matter (SOM). Exogenous carbon (C) and nitrogen (N) are assimilated by soil microorganism, accumulated as microbial necromass and contributed to relatively stable SOM. The objectives of this study were to clarify the accumulation of microbial residue C and N in different fertility levels of soil with straw and root residues addition, and qualify the contributions of microbial residue C and N to soil organic C (SOC) and total N (TN), respectively. This study would provide a basis for increasing the storage and stability of SOC and TN.【Method】Based on a long-term experiment of black soil with different fertility levels, this study used the 13C15N isotope labeling and amino sugar biomarkers methods, and mixed the labeled maize straw and root residues with black soil samples. Then the mixture samples were incubated in lab, and sampled in 30 and 180 days. The percentages of exogenous C (straw C and root C) and N (straw N and root N) remaining in soil, contents of microbial residues C and N, and their contributions to SOC and TN were analyzed.【Result】On the 180th day, the percentages of straw C and root C remaining in soil were, on average, 36.3% and 31.7%, and those of straw N and root N remaining in soil were, on average, 95.8% and 79.3%, respectively. On the 180th day, the ratio of the SOC derived from exogenous C (13C-SOC) to TN derived from exogenous N (15N-TN) were, on average, 17.6 and 28.5 in the soils with straw and root residue addition, respectively. The ratio of 13C-SOC to 15N-TN was decreased by 47.9% and 28.2% in the soils with straw and root residue addition on the 180th day compared with the 30th day, respectively. During the incubation, the contents of fungal and bacterial residue in the high fertility soil were, on average, 1.17 and 1.31 times those in the low fertility soil, respectively. On the 180th day, the content of microbial residue C and N (fungal and bacterial) was, on average, 8.50% higher in the soil added with straw than that in the soil added with root. On the end of incubation, the average percentage of fungal residue C contributed to SOC was 37.0% and 33.8%, and that of bacterial residue C contributed to SOC was 11.2% and 9.18% in the high and low fertility level soils, respectively. The average percentage of fungal residue C contributed to SOC was 36.0% and 34.7%, and that of bacterial residue C contributed to SOC was 55.2% and 16.3% in the soil added with straw and root on the 180th day, respectively. The average percentage of fungal residue N contributed to TN was 63.5% and 60.5%, and that of bacterial residue N to TN was 16.4% and 17.5% in low and high fertility level soils on the 180th day, respectively. The percentage of bacterial residue C and N contributed to SOC and TN was increased by 4.79% and 7.35% in the high fertility soil and by 20.3% and 32.5% in low fertility soil on the 180th day compared with the basic soil without straw addition, respectively.【Conclusion】The accumulation of fungal residue is of great significance for the storage and stability of SOC and TN. Maize straw addition promotes the accumulation of microbial residues C and N in soil compared with root addition. Low fertility soil with the addition of straw and root improves the transformation of bacterial residue C and N to SOC and TN.


]]> <![CDATA[Comparison of Imputation Accuracy for Different Low-Density SNP Selection Strategies]]> 】To facilitate low-cost genomic selection in Huaxi Cattle, the present study represent the first attempt to designed a new low-denstity Genotype chip to support imputation to higher density genotypes. The representative SNP markers with different density gradients were selected from high-density SNP chips in the Huaxi Cattle reference population by using two SNP selection methods. And then these marker sets were imputed to high-density sets with the same imputation parameters for subsequent genomic studies. Meanwhile, the current study compared the differences in imputation accuracy and concordance among SNP panels and illustrated the effects of four factors on imputation results including marker screening method, marker density, minor allele frequency and the number of reference population. This study provides insights about the methods to select low-density SNP markers for imputation in the current population and the representative SNPs will aid in designing low-density SNP chip for Huaxi cattle.【Method】Totally 1,233 Huaxi cattle after genotypes filtered was randomly divided into reference (986) and validation (247) populations. two SNP selection strategies, based on Equidistance (EQ) and on high MAF (HM), were used to make 16 SNP sets with different densities from the Illumina Bovine HD chip in the reference population, respectively. Each of the 32 low-density set was then imputed to the 770K density level in the validation population using Beagle (v5.1), while the imputation accuracy and concordance were calculated as the mean correlation between true and imputed genotypes. While, a comprehensive set of factors that influence the imputation performance were analyzed.【Result】The number of markers in the 32 low-density SNP sets ranged from 100 to 16 000, with a maximum window of 24 176 kb and a minimum window of 151 kb. The imputation accuracy and concordance of both EQ and HM methods went up with increasing marker densities. The imputation accuracy of both methods was highest at 16k SNP density （r2EQ=0.8801，r2MAF=0.8696）. When the marker density was below 11k, the imputation concordance of HM was higher than EQ for all marker density gradients. However, when the SNP density exceeded 11k, EQ showed an imputation accuracy advantage over HM. Similar to the imputation concordance results, the HM method still had higher imputation accuracy when the SNP density was lower than 10k, but the EQ method had higher imputation accuracy when the SNP pool density was higher than 10k, and the EQ imputation accuracy tended to be stable after the SNP density was greater than 12k. It was also found that the imputation accuracy of high MAF locus was higher. During the imputation process, it was found that the imputation accuracy and concordance increased with the increase of the reference panel. The imputation accuracy and concordance of loci were higher when the population of the reference panel was 600-800. 【Conclusion】In the Huaxi cattle population, imputation accuracy and concordance increased with increasing marker density, and a better imputation effect could be obtained in the marker density of 10k-12k interval. The HM method was preferred when the marker density was less than 10k, and the EQ method was better at high marker density. High MAF locuses were more accurate for imputation. When using the imputation strategy for low-density marker imputation, the number of reference panel should be at least 400 heads for better imputation effect.]]> <![CDATA[Effects of Different Varieties of Phosphate Fertilizer Application on Soil Phosphorus Transformation and Phosphorus Uptake and Utilization of Winter Wheat]]> 】Effects of different phosphate (P) fertilizers application on soil phosphorus transformation as well as phosphorus uptake and utilization in wheat were investigated, which will provide theoretical basis for precise matching and efficient utilization of P fertilizer in soil - P fertilizer - crop system. 【Method】The pot experiment was conducted in Lime concretion soil and red soil including six treatments: no phosphate fertilizer (CK); application of calcium superphosphate (SSP), calcium magnesium phosphate (FMP), diammonium phosphate (DAP), calcium superphosphate (TSP) and ammonium polyphosphate (APP). The relationship between the phosphorus transformation in rhizosphere as well as non-rhizosphere soils with phosphorus accumulation in wheat at the jointing and anthesis stages was analyzed. 【Result】Soil Olsen-P concentration increased by 194%-662% after application of P fertilizer in Lime concretion soil. Soil Olsen-P concentration in wheat rhizosphere soil followed the order: APP, TSP, DAP, FMP, SSP, CK. The H2O-P and NaHCO3-Pi concentration was significantly increased, whereas the Residual-P concentration was significantly reduced after phosphate fertilizer application. Both H2O-P and NaHCO3-Pi concentration was positively correlated with soil Olsen-P. At the jointing stage, in comparison to that of the control, TSP and APP application increased NaHCO3-Pi concentration by 41.0 and 36.0 mg·kg-1 respectively. For the red soil, soil Olsen-P concentration in rhizosphere soil increased by 84%-791% as P fertilizer was applied. And soil Olsen-P concentration in DAP and TSP treatments was significantly higher than that of other P fertilizer treatments. The NaHCO3-Pi and NaOH-Pi concentration increased by 275.2%-848.3% and 26.9%-58.3% respectively, which was positively correlated with rhizosphere soil Olsen-P concentration. After P fertilizer application, the most significant effects were found in DAP and TSP treatments. At the jointing stage, there was a significant positive correlation between shoot P accumulation and soil Olsen-P concentration in Lime concretion soil and red soil. When soil Olsen-P concentration increased by 1 mg·kg-1, shoot P accumulation increased by 0.87 and 0.37 mg/pot respectively in Lime concretion soil and red soil. In Lime concretion soil, shoot P accumulation significantly increased by 15.44%-50.9% compared with the control as different P fertilizers addition, and the APP and TSP significantly increased shoot P accumulation and utilization efficiency in shoot than other P fertilizers. After P fertilizer application in red soil, shoot P accumulation and grain yield of wheat increased by 123.7%-643.9%, 75.5%-337.2% respectively. The grain yield, shoot P accumulation and P utilization efficiency in TSP treatments were significantly higher than that in other P fertilizer treatments. 【Conclusion】In lime concretion soil the concentration of H2O-P and NaHCO3-Pi was significantly increased after application of APP and TSP. In red soil, the NaHCO3-Pi and NaOH-Pi concentration was significantly increased after the application of DAP and TSP. Therefore, in order to increase wheat P efficiency, APP or DAP was recommended as a proper fertilizer in lime concretion soil, while DAP or TSP was recommended as a proper P fertilizer in red soil.


]]> <![CDATA[The role of sugar transport protein SlSTP2 in tomato defense against bacterial leaf spot and its relationship with the G protein β subunit SlAGB1]]> Background】In recent years, tomato diseases occur frequently in open field and protected cultivation due to the suboptimal environmental conditions. Tomato bacterial leaf spot caused by Pst (Pseudomonas syringae pv. tomato) is a common bacterial disease, which severely affects the yield and quality of tomato. Sugar is an important signaling molecule as well as nutrient substance in plants. When plants are subjected to pathogen attack, sugar not only functions as a signal to regulate the plant defense, but also provides energy for immune responses as a main carbon source. STP (sugar transport protein) family is responsible for the sugar transport, and play an important role in plant growth, development and defense.【Objective】The objective of this study is to clarify whether STP family are involved in the regulation of plant defense against bacterial leaf spot.【Method】CR (Solanum lycopersicum cv. Condine red) was used as the wild-type (WT) background in this study. The responses of STP gene family to Pst DC3000 were determined by Pst DC3000 inoculation. The SlSTP2, which was up-regulated most significantly after Pst DC3000 inoculation, was selected for futher investigation. The Slstp2 homozygous mutant and overexpression materials were generated. To explore the role of SlSTP2 in plant defense against Pst DC3000, WT and slstp2 mutants, OE:SlSTP2 plants were inoculated with Pst DC3000, then the disease symptoms were assessed by disease-associated cell death and bacterial growth as well as the photochemical efficiency. In order to explore the potential mechanism of SlSTP2 in the disease resistance, the interacting proteins were screened by bimolecular fluorescence complementary assay. The mutant material and overexpression materials of candidate interacting protein was generated and inoculated with Pst DC3000 to investigate its role in plant defense against bacterial leaf spot. 【Result】After inoculation with Pst DC3000 on tomato plants, the expression of SlSTP1 and SlSTP2 were up-regulated. SlSTP2 was up-regulated most significantly, so it was selected for futher investigation and its mutant and overexpression material was generated. WT and Slstp2 mutants, OE:SlSTP2 plants were subjected to Pst DC3000 inoculation. Compared with WT plants, Slstp2 mutants showed significantly increased susceptibility, as evidenced by more severe disease symptoms, increased disease-associated cell death, an enhanced bacterial population and a decreased photochemical efficiency in the leaves. On the contrary, OE:SlSTP2 plants showed enhanced defense against Pst DC3000 compared to WT plants. It was further found that SlSTP2 interacted with the G protein β subunit SlAGB1 using bimolecular fluorescence complementary assay. Similar to the Slstp2 mutants, the Slagb1 mutants also showed significantly increased susceptibility to Pst DC3000 compared with WT plants, and OE: SlAGB1 plants showed enhanced defense against Pst DC3000 as OE: SlSTP2 plants.【Conclusion】SlSTP2 is significantly induced by Pst DC3000 inoculation, and positively regulates the defense against Pst DC3000 in tomato. SlSTP2 interacts with SlAGB1, which also plays a positive role in defense against bacterial leaf spot, suggesting that SlSTP2 associated with SlAGB1 regulate tomato resistance to bacterial leaf spot.


]]> <![CDATA[Commercialization status and existing problems of RNA biopesticides]]> s of companies based on RNAi technology for pest control have emerged, which has greatly accelerated the industrialization of RNA biopesticides. With the rapid development of RNA biopesticides, it will be bound to change the global pesticide market pattern, which is undoubtedly a new challenge. Although the R&D program in this field started early and the starting point is relatively high in our country, most of the research mainly focuses on basic theories, and the application development is relatively weak, which has lagged far behind the international counterparts. Compared with traditional pesticides, RNA biopesticides have their own unique features in both mechanism and application development. Improve the corresponding laws and regulations to supervise and guide production, promote the rapid development of RNA biopesticides in our country, and reduce the risk of international pesticide giants forming a technological monopoly in this field. Based on this, this paper systematically summarizes the current domestic and foreign R&D status, commercialization, and future development trends of RNA biopesticides, as well as the regulations and policies related to RNA biopesticides in Europe, the United States and other countries. In addition, the paper also pointed out some urgent problems in the progress of R&D and industrialization of RNA biopesticides, hoping to provide a useful reference for the development and supervision of RNA biopesticides in China.


]]> <![CDATA[The miR-221 Inhibits the Viability and Proliferation of Ovine Mammary Epithelial Cells by Targeting IRS1]]> 】MicroRNAs (miRNA) are a type of small RNAs (18~23 nt) that are widely involved in the regulation of mammogenesis and milk traits in livestock animals. In our previous research, the expression level of miR-221 in non-lactating mammary gland was found to be 3.6-time higher than in mammary gland at lactation period in Small-Tailed Han sheep using RNA-Seq. However, the regulatory mechanism of miR-221 on ovine mammary gland development is still unclear. 【Objective】The aim of this study was to investigate the effect of miR-221 on the viability and proliferation of sheep mammary epithelial cells by targeting IRS1 gene, and to provide a theoretical reference for revealing the molecular regulation mechanism of miR-221 on sheep lactation performance.【Method】In the study, mammary gland, heart, liver, kidney, spleen, lung, Longissimus dorsi muscle and ovary tissues were collected in Small-Tailed Han sheep, and the expression profiles of miR-221 were constructed in ovine eight tissues using reverse transcription-quantitative PCR (RT-qPCR). The effect of miR-221 on the viability and proliferation of ovine mammary epithelial cells (OMECs) were investigated using cell transfection, CCK-8 and Edu assays. The miRDB and miRanda were used to predict the target genes of miR-221. Based on functional enrichment analysis, an investigated target gene was screened. The target relationship between miR-221 and the predicted target gene was investigated by constructing wild-type and mutant-type report vectors for the target gene using dual luciferase reporter assay. Finally, the effect of over-expressed and silenced miR-221 on expression levels of the target gene and other functional genes in downstream signaling pathways was detected.【Result】The miR-221 was expressed in ovine eight tissues including mammary glands, with the highest expression levels in lung and spleen, and the lowest expression levels in Longissimus dorsi muscle and kidney. The CCK-8 assay result revealed that miR-221 mimic inhibited the viability of OMECs, whereas miR-221 inhibitor promoted the viability of OMECs. The Edu result found that miR-221 mimic reduced the number of Edu-labeled positive OMECs. On contrary, miR-221 inhibitor increased the number of Edu-labeled positive OMECs. The result from dual luciferase reporter assays showed that the miR-221 mimics reduced the luciferase activity of the 3?UTR region of insulin receptor substrate 1 (IRS1). On contrary, miR-221 inhibitor increased the luciferase activity. This suggests that IRS1 is a target gene of miR-221. The results from RT-qPCR further found that the over-expressed miR-221 reduced expression levels of IRS1 and PIK3R1 in OMECs (P<0.05), while silenced miR-221 enhanced the levels of these two genes in expression (P<0.05). No effect on IGF1R was found for over-expressed and silenced miR-221 in OMECs (P>0.05).【Conclusion】The results show that miR-221 inhibited the viability and proliferation of OMECs by reducing IRS1 expression.


]]> <![CDATA[Effects of Control Irrigation on Grain Yield and Greenhouse Gas Emissions in Ridge Cultivation Direct-Seeding Paddy Field]]> Objective】Paddy fields are one of the important sources of greenhouse gas emissions, farming practices and water management can reduce greenhouse gas emissions from field to a certain extent. Ridge cultivation and direct-seeding is a new kind of rice planting pattern that saves costs and increases economic efficiency, However, there are few studies on the comprehensive effects of water management on greenhouse gases and rice yield under ridge cultivation and direct-seeding. Exploring the impact of water management of ridge cultivation and control irrigation on grain yield and greenhouse gas emissions is of great significance for increasing grain yield and reducing greenhouse gas emissions. Exploring the effects of control irrigation on grain yield and greenhouse gas emissions in ridge cultivation direct-seeding paddy field can provide theoretical basis and technical approaches for the innovation of high-yield and emission-reduction. 【Method】In this study, a rice-radish rotation system under the ridge cultivation from 2019 to 2021 was conducted to use as the research object. By setting up traditional flooded furrow irrigation (TFI: the moisture is about 5 cm above the ridge), controlled furrow irrigation 1 (CFI1: moisture is about 5 cm below the ridge), controlled furrow irrigation 2 (CFI2: the moisture is about 10 cm below the ridge), and control furrow irrigation 3 (CFI3: the moisture is about 15 cm below the ridge) four treatments. The research includes studying the greenhouse gas emissions and global warming potential(GWP) of rice-radish season by airtight static box-gas chromatography, measuring the rice yield, soil reducing substances, ammonium nitrogen and nitrate nitrogen, identifying optimal irrigation patterns that both reducing the GWP and increasing the rice yield.【Results】Based on the three-year experimental results, compared with TFI treatment, controlled irrigation can significantly reduce the cumulative emission of CH4 by 22.81%-78.47% in the rice season, of which CFI3 has the most significant effect; CFI2 treatment significantly increases the cumulative emission of N2O by 20.45%-59.90% , CFI3 significantly reduced the cumulative N2O emissions by 12.08%-41.41%, and CFI1 had no significant effect on the cumulative N2O emissions. For radish season, compared with TFI controlled irrigation can significantly reduce the cumulative emission of CH4 by 34.87%-53.31%, among which CFI2 and CFI3 have the most significant effects; CFI1, CFI2 and CFI3 treatments can significantly increase the cumulative emission of N2O by 35.00%-120.00%. The results of two-way ANOVA showed that control irrigation, the interaction of control irrigation and year had a extremely significance on the cumulative emission of CH4 (P<0.01). The control irrigation, year, the interaction of control irrigation and year had a extremely significance on cumulative N2O emissions (P<0.01). Compared with TFI, controlled irrigation treatment can significantly reduce GWP by 20.24%-74.87% in rice season; CFI1 and CFI2 treatments increases rice yield by 12.34%-33.97%, CFI3 treatment has no significant effect on yield. Controlling irrigation reduced GHGI by 29.37%-75.92%. Controlled irrigation  affects CH4 emissions by reducing the total amount of reducing substances, active reducing substances and reducing Fe2+ by 15.00%-30.84%, 53.45%-71.65% and 60.47%, respectively. It also affects N2O emissions by reducing NH4+ by 7.51%-9.87% and increasing NO3- by 5.81%-8.55%.【Conclusion】Controlled irrigation affects GHG emissions through soil properties such as NO3-, NH4+, and reducing substances. Therefore, CFI1 and CFI2 have the best effects in terms of reducing GWP and increasing rice yield. Under the conditions of ridge cultivation and direct-seeding in paddy field, the depth of irrigation is two-thirds or half of the depth of traditional furrow irrigation flooding is the best water management method to alleviate greenhouse gas emissions and increase rice production.]]> <![CDATA[Spatio-Temporal Variations of Fertilizer Contribution Rate for Rice in China and Its Influencing Factors]]> 】 Spatio-temporal variations and driving factors of fertilizer contribution rate were conducted for the paddy soil in China. It can provide a theoretical basis for the sustainable development of rice and scientific recommended application of fertilizers in rice cultivation areas. 【Method】Data was cited from a total of 338 long-term paddy soil monitoring sites located in rice-producing provinces of China for this study. The effects of fertilizer contribution rate for cropping system, climate, regions, soil texture and its driving factors were evaluated. 【Result】In the past 30 years (1988-2017), the fertilizer contribution rate for rice increased first and then levelled off in China in the condition of same rice variety and cultivation techniques both in fertilization and none-fertilization plots. The variable range of fertilizer contribution rate for rice was from 41.20% to 51.89%. The fertilizer contribution rate for rice was 38.58%-55.49%, 41.96%-51.05% and 41.96%-51.05% in single, double rice and rice and other cropping systems, respectively. After 30 years, fertilizer contribution rate for rice from high to low was as follows: Southwest China (55.82%), Middle of Yangtze River (46.73%), North China (46.27%), North east China (45.90%), South China (45.83%) and Lower of Yangtze River (44.25%). According to the fitting equation, it was found that the stable fertilization years of fertilizer contribution rate for rice was 15.2 a, 18.5 a, 19.0 a, 15.3 a, 15.3 a and 14.5 a in the Northeast China, North China, Southwest China, Middle of Yangtze River, Lower of Yangtze River and South China, respectively. The fertilizer contribution rate for rice in Subtropical monsoon (49.23%) was much higher than Temperate monsoon (45.90%) and Tropical monsoon (34.57%). The fertilizer contribution rate for rice with different soil texture was 43.25%-64.80% for clay soil, 40.65%-48.46% for loam soil, and 26.20%-45.98% for sand soil. Among the fertilization factors, nitrogen and phosphate fertilizer were the main factors affecting fertilizer contribution rate. Among the climatic factors, frost-free period, mean annual rainfall and mean annual temperature were the main factors and soil organic matter was the most important one among the soil factors. 【Conclusion】 The fertilizer contribution rate for rice was increased first and then levelled off in 1988-2017, there was different for fertilizer contribution rate for rice under different rice cropping systems, regions, climate and texture. Nitrogen and phosphate fertilizers were main factors of fertilizer contribution rate for rice in China. Moreover, soil organic matter in paddy soil was the most important to fertilizer contribution rate for rice in soil fertility indexes. 


]]> <![CDATA[Application of <em>Yr52</em> Genes in Wheat Improvement for Stripe Rust Resistance]]> Objective】The objective of this study is to evaluate the application value of the high temperature adult plant (HTAP) resistance gene Yr52 in wheat production for improving stripe rust resistance. And wheat lines with good agronomic characters and high disease resistance were developed and selected. It laid a foundation for making full use of the existing HTAP resistance resources and improving the yield related traits.【Method】 The stripe rust resistance gene Yr52 was introgressed to Lunxuan 987 (LX987), Banong Aikang 58 (AK58) and Han 6172 (H6172) by backcrossing and self-crossing combined with marker-assisted selection breeding. Adult-plant resistance of donor parent, receptor cultivars and their progeny lines were evaluated in the disease nursery fields at Mianyang, Sichuan and Yangling, Shaanxi by mixed endemic physiological races CYR32, CYR33 and CYR34. Comparison to the Chinese Spring reference genome, the flanking SSR markers Xcfa2040 (6.8 cm-Yr52) and Xbarc182 (1.2 cm-Yr52) of Yr52 were combined to search for markers of 35K SNP chip in the physical interval of target genes, and developed into derived cleaved amplified polymorphic sequences (dCAPS) and kompetitive allele specific PCR (KASP) markers. The resistance gene Yr52 was detected in BC2F5:6 progency lines.【Result】The evaluation of adult plant resistance and agronomic traits indicated that nineteen BC2F5:6 lines with LX987 background was obtained: Among of them, 11 were high resistance (IT=0-3, DS=1%-20%), 8 were moderate resistance (IT=4-6, DS=15%-30%), the average thousand kernel weight (TKW), kernels per spike (KPS), productive tiller number per line (PTN), plant height (PH) and spike length (SL) was 45.33 g, 46, 7, 113.26 cm and 10.05 cm, respectively. Four BC2F5:6 families with AK58 background: all showed high resistance (IT=0-3, DS=5%-25%); the average TKW, KPS, PTN, PH and SL were 44.67 g, 48, 7, 96.54 cm and 10.17 cm, respectively. Five BC2F5:6 lineages with H6172 background showed high resistance to stripe rust (IT=0-3, DS=5%-20%). The average TKW, KPS, PTN, PH and SL were 43.74 g, 49, 8, 109.72 cm and 10.06 cm, respectively. The detection rate of three simple sequence repeat (SSR) molecular markers Xbarc182, Xcfa2040 and Xwmc557 linked to Yr52, in offspring population were 78.57%, 66.67% and 66.67%, respectively. One dCAPS marker Xdcaps-Yr52-1 and one KASP marker Xkasp-Yr52-1 were successfully developed, and the detection rates were 73.68% and 41.67%, respectively. The agronomic traits of lines with high (IT=0-3) and medium (IT=4-6) resistance levels were compared. The results showed that the average TKW, PTN and KPS of lines with IT=0-3 were higher (P>0.05) than those of families with moderate resistance level lines (IT=4-6). Five lines with disease resistance and stable agronomic traits were selected by evaluated of PH=80-105 cm, PTN≥6，KPS≥45, TKW≥42 g, SL≥8 cm.【Conclusion】Yr52 was found to be resistant to all of the present predominant races in the adult plant stage. After introgression Yr52 into the main susceptible Chinese wheat varieties, the progeny lines with good disease resistance and agronomic characters could be used for breeding resistance varieties with multi-gene polymerization, it is enriching for the diversity of disease resistance genes and achieving durable utilization. The development of molecular markers will facilitate detect the utilization of Yr52 gene in resistance identification of germplasm in the future.


]]> <![CDATA[Cloning and stress resistance analysis of transcription factor <i>GhMYB108</i> in<i> Gossypium hirsutum </i><i></i> #br#]]> Objective】As one of the largest transcription factor families in plants, MYB genes play an important role in resisting stress. The MYB transcription factor GhMYB108 was cloned and analyzed to verify its role in drought stress response, which laid a foundation for further study on the molecular mechanism of GhMYB108 regulating drought tolerance in G. hirsutum.【Method】Through the analysis of unpublished drought transcriptome data, GhMYB108 was identified to drought response. The target gene was amplified from the Root cDNA by polymerase chain reaction (PCR). Through bioinformatics analysis of gene structure characteristics, the sequence information and phylogenetic relationship of these genes were predicted. The obtained gene promoter sequences were analyzed by Plant care website. The genes expression characteristics under different stress conditions were analyzed using Real time fluorescence quantitative PCR (qRT-PCR). The location of GhMYB108 protein was determined by subcellular localization. The transcriptional activity was tested in yeast cell; The GhMYB108 gene was silenced using Virus induced gene silencing (VIGS), and the gene silencing efficiency was detected by qRT-PCR. The phenotypic changes before and after drought treatment were observed and the survival rate was counted. The relevant physiological and biochemical indexes were measured by Solarbio kit; The relationship between GhMYB108 and ABA was analyzed by spraying ABA and Fluridone on cotton leaves. 【Result】GhMYB108 (Gh_A10G1563) was cloned from G. hirsutum, with 879 bp length and 292 amino acids. Its protein relative molecular weight and isoelectric point is 33.288 kD and 6.037, respectively. Multiple sequence alignment and conserved domain analysis showed that GhMYB108 contains two highly conserved MYB binding domains, which belongs to a typical R2R3 MYB transcription factor. Phylogenetic analysis of different species showed that GhMYB108 was highly homology with ATMYB108, ATMYB78 and ATMYB2, belonging to the same subfamily. Previous studies found that ATMYB108, ATMYB78 and ATMYB2 were related to drought and ABA signaling pathway. GhMYB108 located in the nucleus and had transcriptional activation activity. The expression level of GhMYB108 was the highest in roots and the lowest in stems, and was induced by abiotic stresses including natural drought, 18%PEG 6000 simulated drought, salt stress and low temperature. The GhMYB108 silenced plants showed a critical phenotype under natural drought conditions. Compared with the control, the silenced plants showed more serious wilting and decreased survival rate. Some physiological and biochemical indexes also changed significantly, such as accelerated leaf water loss rate, increased malondialdehyde content, decreased leaf relative water content and proline content, and decreased CAT and POD activities. Through DAB and NBT staining, the hydrogen peroxide (H2O2) and superoxide anion (O2-) were significantly accumulated in plants. By spraying the hormone ABA or Fluridone on cotton leaves, we found that GhMYB108 could be positively regulated by ABA signal.【Conclusion】 GhMYB108 positively regulates Cotton Drought Resistance and is positively regulated by ABA signal.


]]> <![CDATA[Accounting Framewrok of Carbon Footprint on Integrated Cropping-Breeding Farming System: A Case on Maize-Cow-Recycling Manure Model]]> Objective】To conduct a comprehensive assessment of the carbon sequestration and emission reduction effect of the whole life cycle of complex integrated cropping-breeding farming system based on scientific agricultural carbon assessment method, which is the basis for the design and optimization of low-carbon farming system in China from the perspective of the whole industry chain. This study compared five system scenarios and their corresponding carbon footprint assessment frameworks for crop-livestock cycle industry chain, intending to provide scientific, reasonable and usable methodological references for the creation of low-carbon farming systems. 【Method】A carbon footprint accounting based on life cycle assessment published by ISO 14040 and greenhouse gas accounting provided by IPCC were combined in this study to construct a carbon footprint evaluation framework for the integrated cropping-breeding farming systems under the different system boundaries. The Maize-Cow-Recycling Manure model in tropical crop areas of South China was used as case to validate the effect of the proposed accounting framework. 【Result】 The assessment framework clarified that the whole chain of the integrated and separated crop-livestock models both had six accounting links, including agricultural inputs, crop cultivation, animal breeding, manure management, transportation and soil carbon sink. Furthermore, the carbon measurement logic of each link and its carbon footprint accounting method were analyzed. The case results showed that the whole-life carbon footprint of the integrated crop-livestock model was 20.73% lower than that of the separated model, showing better carbon sequestration and emission reduction effect. The assessment framework could fully reflect the "indirect emissions" of upstream agricultural production and transportation, as well as the "alternative emissions reduction" of downstream feed substitution and waste recycling after "coupling" or "decoupling" of farming. In addition, the evaluation results were more closely related to the actual production of the farming system in the integrated cropping-breeding farming system by combing the field measurement data and research data as well as the model evaluation parameters of the background system. 【Conclusion】The carbon footprint assessment framework of farming systems in the integrated cropping-breeding farming system constructed in this study was able to conduct a comprehensive carbon sequestration and emission reduction effects of the industrial chain in integrated and separated systems under the whole life cycle perspective and reasonable system boundary, which could provide directions for optimization.


]]> <![CDATA[Function of βCA3 in plant defense against Pseudomonas syringae pv. tomato DC3000 and its relationship with sugar signaling in tomato]]> Background】With global climate change, the increase of atmospheric CO2 concentrations is predicted to exert an influence on plant diseases, which seriously affects agricultural production. Plant β-carbonic anhydrases (βCAs) are involved in the immunity of Arabidopsis and tobacco. However, little is known about the functions of βCAs in the regulation of disease resistance in tomato.【Objective】The objective of this study is to explore the role and mechanism of tomato βCA3 in disease resistance, so as to provide scientific basis for resistance regulation of tomato in agricultural production.【Method】Based on the similarity to the amino acid sequences of AtβCAs, four βCAs were identified in the Sol genomics network database. Wild-type (WT) tomato (Solanum lycopersicum) ‘Ailsa Craig’ (AC) was used to inoculate Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) in the study. Then qRT-PCR was used to determine the transcript abundance of βCAs in leaves to screen the Pst DC3000-induced gene βCA3. Furthermore, βCA3 stable over-expression lines (OE-βCA3) were generated by Agrobacterium tumefaciens-mediated genetic transformation technology as the background of AC. OE-βCA3 plants were inoculated with Pst DC3000 to investigate the role of βCA3 in disease defense. For exploring the intrinsic mechanism of βCA3 regulating plant disease resistance, the transcriptome changes of WT and OE-βCA3 plants between inoculation with Pst DC3000 and control conditions were compared, and KEGG (kyoto encyclopedia of genes and genomes) database was used to analyze functions of the differentially expressed genes. It is speculated that sugar metabolism pathways are involved in βCA3-mediated plant immunity. To verify and further analyze the conclusion, the expression of genes related to the sugar metabolism and signaling, as well as the contents of glucose, fructose and sucrose in WT and OE-βCA3 plants were determined.【Result】OE-βCA3 plants enhanced the resistance to Pst DC3000, and showed less disease-associated cell death and a lower number of bacteria compared to the WT controls. RNA-Seq results showed that OE-βCA3 did not greatly change the overall transcript profile in the absence of the pathogen. In total, 2100 Pst DC3000-induced transcripts were differentially changed in abundance. Of these, 63.3% were more abundant following Pst DC3000 inoculation in the OE-βCA3 plants. KEGG analysis showed that Pst DC3000-induced genes, which is dependent on βCA3-overexpression, were enriched in the pathways related to sugar metabolism, including starch and sucrose metabolism, protein processing in the endoplasmic reticulum (glycosylation), amino sugar and nucleotide sugar metabolism, ribosomal biosynthesis in eukaryotes and photosynthesis. Sugar metabolism is closely related to sugar signaling. Further studies found that the expression of genes related to sugar metabolism and signal transduction pathways, as well as the contents of glucose, fructose and sucrose, were higher in the leaves of OE-βCA3 plants than that of WT after inoculation with Pst DC3000.【Conclusion】Overexpression of βCA3 in tomato enhances the resistance of plants to Pst DC3000, possibly related to the role of sugar metabolism and signaling in plant immunity.


]]> <![CDATA[Peptidome Analysis of Mesocarp in Melting Flesh and Stony Hard Peach during Fruit Ripening]]> Objective】To explore the differences between melting flesh and stony hard peaches at the peptide level and precursor protein level during fruit ripening. The study provides a theoretical basis for mining the key peptides that determine or regulate the ripening process.【Method】 The characteristics of peptides and precursor protein functions in ‘CN13’ (melting flesh, MF) and ‘CN16’ (stony hard, SH) peaches were analyzed by peptidome, the relative contents of precursor proteins and peptides during MF and SH peach fruit ripening were compared, and the precursor proteins of different peptide segments.was analyzed by function enrichment.【Result】In this study, the peptides of ‘CN13’ and ‘CN16’ (S3 and S4III) were extracted for mass spectrometry. A total of 473 precursor proteins were identified, including 2580 specific peptide sequences. The molecular weight, isoelectric point and cleavage sites of the peptide were summarized. In addition, the high-abundance precursor proteins corresponding to endogenous peptides were explored by COG function annotations and pathway enrichment analysis. The results showed that the precursor proteins were mainly involved in the processes of general function prediction, post-translational modification, protein turnover, energy production and conversion, carbohydrate transport and metabolism. The enrichment analysis showed that the differential peptide precursor proteins of ‘CN13’ were related to biological processes such as oxidation reduction, oxygen and oxygen and electron transport chain, and were mainly involved in glycolysis/gluconeogenesis, pentose phosphate pathway and RNA transport; The differential peptide precursor proteins in ‘CN16’ were related to biological processes such as response to metal ion, response to inorganic substance, response to cadmium ion, and were mainly involved in microbial metabolism in diverse environments, spliceosome and RNA transport; The differential peptide precursor proteins at the same stage in ‘CN13’ and ‘CN16’ at S4III were related to gene expression, translation and cellular macromolecular biological processes, and were mainly involved in RNA degradation, RNA transport and splicing.【Conclusion】There are significant differences in peptides between ‘CN13’ and ‘CN16’ during fruit ripening. The precursor proteins of differential peptide are involved in starch / sucrose metabolism, glycolysis and ribosome synthesis, it is suggested that these metabolic pathways are closely related to peach fruit ripening, which provides a theoretical reference for further exploring the key peptides which regulating peach fruit ripening and senescence..


]]> <![CDATA[Optimization of callus genetic transformation system and its application in <i>FtCHS1</i> overexpression in tartary buckwheat]]> Agrobacterium tumefaciens types were systematically evaluated using "Xiqiao No. 2" as the derived plant. We further overexpressed FtCHS1, a key enzyme gene involved in the biosynthesis of tartary buckwheat flavonoids in obtained calli to validate the optimized genetic callus transformation system. The positive transgenic lines were confirmed by PCR and fluorescent observation. Subsequently, the content of anthocyanins and metabolites in flavonol branch pathway were determined by UV spectrophotometry and High Performance Liquid Chromatography (HPLC), respectively. Furthermore, quantitative real-time PCR was performed to analyze expression levels of genes involved in flavonoid synthesis, in order to compare the differences between the FtCHS1-overexpressed calli and the control. 【Result】The optimal explant was hypocotyls and the optimal induction medium was the Murashige and Skoog (MS) medium supplemented with the addition of 0.8 mg·L-1 6-BA (6-Benzylaminopurine) and 3.5 mg·L-1 2,4-D (2,4-Dichlorophenoxyacetic acid). The induction rate of calli grown on the above medium reached up to 72%. Moreover, the optimized subculture medium containing MS with the additives of 3 mg·L-1 6-BA and 1 mg·L-1 KT (Kinetin) increased the percentage and coefficient of callus proliferation to 0.98 and 1.09, respectively. Additionally, the best Agrobacterium tumefaciens in the transformation process was GV3101, and the transformation efficiency was up to 31.3%. The functional analysis of FtCHS1 overexpressing in transgenetic calli demonstrated that (1) the accumulations of kaempferol and quercetin in transgenic calli overexpressing FtCHS1 were dramatically higher than those in control groups (P<0.01), and anthocyanin, rutin and myricetin contents were also remarkably higher (P<0.05); (2) overexpression of the exogenous FtCHS1 did not affect the expression levels of 5 endogenous orthologous genes FtCHSs in the transgenic calli (P>0.05), whereas genes encoding key enzymes of the flavonoid synthesis pathway, such as FtCHI, FtF3H, FtFLS1, FtFLS2, FtFLS3 and FtDFR1, were upregulated (P<0.05); (3) FtMYB5 and FtMYB 6, the transcription factor genes that specifically positively regulated the flavonol synthesis, were up-regulated, while FtMYB8, a suppressor gene of anthocyanin synthesis, was down-regulated (P<0.05). 【Conclusion】In this study, the callus genetic transformation system of tartary buckwheat was successfully established from “Xiqiao No. 2.”. FtCHS1 overexpression in the transgenic calli up-regulated genes related to flavonoid synthesis, resulting in flavonoids accumulation.


]]> <![CDATA[Identifying New QTLs for Teat Number Traits of Pig by Genome Analysis]]> 】The purposes of this study were to analyze the variation of teat number, to explore the quantitative trait locus (QTL) and candidate genes related to teat number, and to provide important molecular markers for the breeding of pig teat number.【Method】This study accurately measured left, right, total teat number of 709 Suhuai pigs (335 fattening pigs and 374 breeding pigs). Fattening pigs were selected for 80K chip genotyping and the heritability and genomic estimated breeding value (GEBV) of left, right and total teat number were calculated by chip data. Based on the rank of GEBV and phenotype of teat number, the top 10% individuals and the bottom 10% individuals were selected for Fixation Index (FST) analysis to detect highly differentiated loci. Then, the loci associated with teat number were identified by genome wide association analysis (GWAS) and loci which were highly differentiated and significantly associated with teat number were selected as candidate loci. Genes located near candidate loci and related to teat number after functional annotation were selected as candidate genes. Finally, the association analyses between the most significant candidate loci on each chromosome and teat number of 709 Suhuai pigs were performed to verify the significance of the above loci.【Result】The variation coefficients of left, right and total teat number of Suhuai fattening pigs were 10.20%, 9.26% and 8.50%, respectively, and the heritability were 0.212, 0.257 and 0.312, respectively. Based on FST and GWAS analyses, a total of 20 candidate loci on Sus scorfa chromosomes (SSC) 7, 13, 16 and 18 for teat number were identified and these candidate loci could explain 5.49%-8.03% of the phenotypic variance. Among them, locus rs80894106 on SSC7 associated with total teat number was consistent with the reported candidate locus of total teat number based on Large white and Duroc pig populations, but candidate loci rs81444134 (26.51 Mb, SSC13) and rs81233299 (8.13 Mb, SSC18) of left teat number were newly discovered loci related to teat number. Interestingly, candidate loci of left, right and total teat number were mainly concentrated in the 6.36-10.66 Mb interval on SSC16; Linkage disequilibrium (LD) analysis found that candidate loci in 7.47-8.27 Mb interval fit into a 795 Kb haplotype block, and this haplotype block was a newly discovered candidate area that affected teat number; rs337606862 (7.47 Mb) in the haplotype block was the most significantly SNP associated with the left and total teat number, and three loci in the haplotype block were all located on the intron of cadherin 18 (CDH18) gene; CDH18 gene encoded type II cadherin, and cadherin was related to the identification, sorting, proliferation, apoptosis of cells in developing tissue and the occurrence of breast cancer. Thus, CDH18 might be a new candidate gene that affected pig teat number. In addition, the most significant loci rs81444134, rs80894106, rs337606862 and rs81233299 on 4 chromosomes were genotyped in 709 Suhuai pigs in this study. After association analysis, these loci were significantly associated with teat number, and could be used as potential molecular markers for the selection of teat number.【Conclusion】In this study, 20 loci significantly related to teat number were identified in Suhuai pig population by genome analysis. Among them, 26.51 Mb on SSC13 and 8.13 Mb on SSC18 were new candidate QTLs for teat number. The 7.47-8.27 Mb on SSC16 was also a newly discovered candidate QTL for teat number, and CDH18 gene in this interval might be a new candidate gene that affected the formation of pig teat.


]]> <![CDATA[Effects of Guanidinoacetic Acid and Betaine Supplementation on Growth Performance, Rumen Fermentation and Blood Metabolites in Lambs]]> Objective】This study was conducted to investigate the effects of dietary guanidinoacetic acid (GAA) and betaine (BT) on growth performance, rumen fermentation and blood metabolites in lambs, so as to provide a support for applying GAA and BT on ruminants.【Methods】Forty-eight 3-month-old Dorper× Thin-tailed Han F1 hybrid male lambs with similar body weight (22.03 ± 1.3 kg; mean ± SD) were randomly divided into 4 groups with a 2×2 factorial arrangement, and the experimental factors were GAA (0 or 900 mg/kg) and BT (0 or 5 g/day). Lambs in four groups were control group, GAA group, BT group and GAA+BT group, respectively. The feeding experiment lasted for 75 days with 15 days of adaptation. On the first day of the formal experiment period, the BW before morning feeding was weighed as the initial BW, and each lamb were recorded accurately the amount of feed and residual of weight every day; at the end of the trial period, blood samples were collected from the jugular vein, and final body weight (FBW) was weighed before morning feeding to calculate average daily gain (ADG), average daily feed intake (ADFI) and feed efficiency (FE). Blood serum was used for the determination of creatine metabolism indexes, homocysteine and lactate content. The rumen fluid was collected from all lambs at 3 hours after feeding at the end of the experiment, which were used to measured rumen fermentation parameters, digestive enzyme activity and functional microorganisms.【Result】The results showed as follows: (1) Compared to the control group, the addition of GAA in the diet did not significantly increase daily weight gain (ADG) (P>0.05), while the addition of BT increased ADG significantly (P<0.05). The addition of GAA or BT in the diet increased feed efficiency (FE) significantly (P<0.05), and GAA and BT had significant interaction on ADG and FE (P<0.05). (2) The rumen pH was decreased by addition of GAA or BT (P<0.05), and the concentration of propionic acid and total volatile fatty acid were increased by GAA or BT (P<0.05). There was no significant interaction between GAA and BT on rumen fermentation in lambs (P>0.05). (3) Addition of GAA or BT increased the populations of R.flavefaciens, F.succinogenes, B.fibrisolvens, P.ruminicola (P<0.05), and decreased the populations of total protozoa (P<0.05). Addition of BT decreased the populations of total methanogens and had a tendency to increase the populations of Rb.Amylophilus (P<0.05, P=0.098). GAA had a tendency to decrease the populations of total methanogens (P=0.088). Addition of GAA and BT had no significant interaction effect on ruminal main functional microflora in lambs (P>0.05). (4) The activity of protease was increased by addition of GAA and BT (P<0.05). Addition of BT increased carboxymethyl-cellulase, xylanase and α-amylase activities (P<0.05)，and had a tendency to increase cellobiase activity(P=0.075). GAA increased pectase activity (P<0.05), and had a tendency to increase α-amylase activitiy (P=0.056). The significant interaction effect between GAA and BT was observed on pectase (P<0.05). (5) Addition of GAA or BT increased the content of creatine in blood serum (P<0.05). Addition of GAA had a tendency to increase the concentration of homocysteine (Hcy) and to decrease L-arginine-glycine amidinotransferase (AGAT) (P=0.053, P=0.056). BT decreased the content of Hcy in blood serum, and had a tendency to increase creatine kinase (P=0.063). GAA and BT had no interactive significant effects on blood metabolites (P>0.05).【Conclusion】In conclusion, addition of GAA or BT promoted rumen fermentation, increased the populations of functional rumen microflora and microbial enzyme activity, elevated serum creatine levels, and decreased the content of homocysteine. However, the combination addition of GAA and BT did not further increase the performance of lambs when compared with the addition of GAA or BT alone.


]]> <![CDATA[Trends of American Soft Wheat Grain Quality and Analysis of Chinese Weak Gluten Wheat Standard Reaching Rate]]> Objective】The consumption of biscuits in China is increasing yearly, but soft wheat, the material for making biscuits, has been in shortage for a long time. American soft wheat is of stable quality and excellent processing performance, and is welcomed by Chinese processing enterprises. Study on the interannual dynamic change of grain quality and the relationship between quality indexes of American soft red winter and soft white wheat in multiple years can provide reference for Chinese weak gluten wheat production.【Method】Based on the quality data of soft wheat published by American Wheat Association from 1999 to 2019, the correlation analysis and cluster analysis were used to analyzed the relationship among wheat grain, flour, dough and baking quality. The fitness of American soft wheat quality to the existing weak gluten wheat standard in China was also analyzed.【Result】For grain quality, mean value of grain protein content (GPC, %), hardness (H), test weight, (TW, g·L-1) and 1000-grain weight (TKW, g) of soft red winter wheat were lower than soft white wheat. The annual variation of quality indexes showed: H > TKW > GPC > TW. For flour quality, the wet gluten content (WG, %) of two kinds of soft wheat were about 22%. Four kinds of solvent retention capacity (SRC, %) of soft red winter wheat were higher than or similar to soft white wheat, and the WG, sedimentation value and four kinds SRC of soft red winter wheat had lower variation coefficients. For dough quality, the development time, stability time (ST, min), alveograph P, L, W value and extensograph parameters of soft red winter wheat were lower than those of soft white wheat, and their water absorption (WA, %) was about 52%. The variation coefficients of farinograph, alveograph and extensograph parameters of soft red winter wheat were lower. According to Chinese weak gluten wheat standard GB 17320-2013, the reaching rate of GPC, WG and ST in soft red winter wheat were 100%,, 100% and 57.1%. The reaching rates of GPC, WG and ST in soft white wheat were 90.5%, 95.2% and 38.1%, respectively. Under GB 17893-1999, GPC, WG and ST of two kinds of soft wheat were as follows: GPC< WG < ST, and the reaching rate was less than 70%. Correlation analysis of soft white wheat showed that there was a significant negative correlation between TKW and GPC, WG, sucrose SRC,H and WG, and a significant positive correlation between GPC and WG, sucrose, lactic acid SRC, sucrose SRC and alveograph W, lactic acid SRC and extensibility. Biscuits diameter was negatively correlated with GPC, W and sucrose SRC, and positively correlated with TW, Biscuits spread ratio was negatively correlated with sucrose SRC. Correlation analysis of soft red winter wheat showed that the protein content of flour was positively correlated with WG and ST, and biscuits diameter was negatively correlated with TW and W.【Conclusion】Soft red winter wheat has softer grain texture, smaller grain weight and weaker dough strength. The TW, flour extraction rate(FER, %) and WA are stable in different years. Soft red winter wheat fit the requirements of Chinese weak gluten wheat standard better, with higher reaching rate. The Chinese weak gluten wheat standard is too strict on GPC, WG and ST. The correlation among quality indexes of soft white wheat was more significant than soft red winter wheat. The GPC, sucrose SRC and alveograph W are significantly correlated with other quality indexes, which can be used to evaluate the quality of weak gluten wheat. The GPC, WG, sedimentation value and alveograph L of soft wheat are similar, which can be classified into same category.


]]> <![CDATA[A Salt Stress Tolerance Effect Study in Peanut Based on Peanut/Sorghum Intercropping System]]> +/K+, and rhizosphere nutrient of peanut were investigated in the present study to evaluate the response of peanut to salt stress under different planting patterns.【Result】In the peanut/sorghum intercropping system, both RII of peanut were negative. However, the negative RII was decreased significantly and the STI was increased significantly in S-IP under salt stress, especially after continuously being planted for two years. Of these, the negative RII of S-IP decreased by 66.78% in 2019 than that of in 2018, and the negative RII of S-IP decreased by 88.76% than N-IP. Furthermore, the STI of S-IP increased by 27.68% than S-SP in both 2018 and 2019. Peanut/sorghum intercropping has been found to change the overall root distribution and architecture by favoring the development of different types of roots, and also affects rhizosphere nutrients of peanut, the rhizosphere soil nutrient content of N-IP and S-IP increased by an average of 6.19% and 3.73% than N-SP and S-SP, respectively. Under salt stress, the content of soil potassium increased significantly compared with normal soil conditions, this may be the initial defensive response utilized by plants to maintain Na+/K+ homeostasis in rhizosphere soil, which regulate Na+/K+ homeostasis in peanut by influencing the Na+ and K+ selective absorption and transportation. Compared with S-SP, the leaf Na+/K+ ratio decreased by 20.63%, the leaf salinity hazard coefficient (LSHC) decreased by 53.95%, and the photosynthetic potential and light energy conversion efficiency were significantly improved. Ultimately the dry matter accumulation capacity and yield potential were improved, in which the yield potential of S-IP has the most obvious increase, and the yield of S-IP increased by 17.95% in 2019 compared with 2018.【Conclusion】Continuous peanut intercropped with sorghum under salt stress could be an effective technique to alleviate peanut negative interactions, which significantly improve STI and alleviate salt stress of peanut by improving soil nutrient status and regulating peanut Na+/K+ homeostasis, which ultimately maintained the dry matter accumulation capacity and increased yield potential.


]]> <![CDATA[Effects of Straw Returning and Nitrogen Fertilizer Types on Summer Maize Yield and Soil Ammonia Volatilization in Guanzhong Area under Climate Change]]> 】Returning straw to the field and applying nitrogen fertilizer can increase crop productivity. However, under the conditions of climate change, different management measures have great uncertainty in the nitrogen utilization of summer maize farmland. It is very important to clarify the impact of straw returning and nitrogen fertilizer types on summer corn yield and soil ammonia volatilization under future climate conditions.【Method】This study used the DNDC model to predict the impact of returning straw to the field and different types of nitrogen fertilizers on summer corn yield and soil ammonia volatilization accumulation in Guanzhong area under different scenarios in the future. Through the verification of field soil temperature, moisture, yield and soil ammonia volatilization test data, the DNDC model could simulate crop yields and soil ammonia volatilization accumulation under different treatments under future climate conditions well.【Result】Both simulation and actual measurement results showed that returning straw to the field increased crop yields and promoted soil ammonia volatilization in the current climate. Compared with ordinary urea, slow-release fertilizers had no significant effect on yield but will significantly reduce soil ammonia volatilization accumulation. Sensitivity analysis showed that both crop yield and soil ammonia volatilization accumulation were the most sensitive to nitrogen application. Under the RCP4.5 emission scenario, single application of stable nitrogen fertilizer (NF1) treatment and single application of urea (NF2) treatment significantly reduced the yield in 2050s-2090s and 2070s-2090s, respectively. Both the treatment of straw combined with stable nitrogen fertilizer (SF1) and the treatment of straw combined with urea (SF2) significant increased in production in 2050s-2090s; under the RCP8.5 emission scenario, single application of stable nitrogen fertilizer (NF1) treatment significantly reduced the yield from 2070s to 2090s, and single application of urea (NF2) treatment showed no significant change. Straw combined application of stable nitrogen fertilizer (SF1) treatment and straw combined application of urea (SF2) treatment were both in 2050s-2090s production increased significantly. Single application of stable nitrogen fertilizer (NF1) treatment under the RCP4.5 emission scenario in 2050s-2090s and under the RCP8.5 emission scenario 2030s-2090s soil ammonia volatilization accumulation significantly increased compared with current climate conditions, for the remaining treatments, the cumulative amount of soil ammonia volatilization in future periods under different emission scenarios would be significantly reduce compared with current climatic conditions.【Conclusion】The DNDC forecast results showed that under the climate conditions of rising temperature and CO2 concentration and changing precipitation in the Guanzhong area in the future, returning straw to the field and applying stable nitrogen fertilizer would significantly increase the yield of summer corn and reduce the accumulation of ammonia volatilization in the soil, and it was the best high-yield and emission-reducing farmland management plan. This research could provide a theoretical basis for coping with climate change and the rational use of straw and nitrogen fertilizer.]]> <![CDATA[Response Mechanism of Citrus Growth to the Ammonium Toxicity in Acidic Soil]]> Objective】Through the monitoring of ammonium levels in soil solutions with different pH values, combined with the study on the effects of ammonium levels on the growth and physiological indexes of orange rootstock seedlings, the response process of citrus to ammonium nitrogen (N) was described, which may provide scientific support for the optimal N management of citrus orchard in acid soil. 【Method】 The experiment was designed as a two-factor experiment, with 2 soils as the main treatment and 5 N levels as the secondary treatment. Using acidic yellow soil and alkaline purple soil as the test soil, seedlings of Xiangcheng (junos Sieb. ex Tanaka) were selected as the test material, and five nitrogen levels of 0 (A0), 50 (A50), 100 (A100), 200 (A200) and 400 mg·kg-1 (A400) were set. The effects of ammonium application level on the concentration of ammonium nitrogen and nitrate nitrogen in soil solution and on the biomass, root morphology, nitrogen absorption, antioxidant system, nitrogen metabolism, MDA content and root activity of citrus were studied. 【Result】 The root length of the citrus with A400 treatment was reduced by 13% when compared with the A0 treatment. And the root vitality was significantly negatively correlated with the ammonium application level. The MDA content of leaves and roots is positively correlated with the ammonium level, which stimulates the oxidative stress response of the roots, especially increases the POD enzyme activity of the leaves. The root, stem, leaf biomass and root-to-shoot ratio of citrus seedlings grown in acid soil were lower than those in calcareous soil. Compared with calcareous soil, the nitrification process in acid soil was slow with  weak nitrification. The NH4+-N concentration and NH4+-N / NO3--N in the soil solution of acid soil remained at a higher level at 30 days of the test. Compared with calcareous soil, the total nitrogen accumulation of citrus on acid soil decreased by 17.6%, while the ratio of ammonium to nitrate in leaves and roots increased by 27.2% and 61.1%, respectively.【Conclusion】 In acidic soil, excessive application of ammonium nitrogen caused the accumulation of ammonium nitrogen in soil solution for a long time, resulting in the increase of MDA content , cell membrane damage and nitrogen metabolism disorders and other ammonium toxic phenomena, indicating that ammonium toxicity in citrus is closely related to excessive application of ammonium nitrogen and soil nitrification which is worth paying attention to in terms of production


]]> <![CDATA[Cloning and expression profiling of gustatory receptor genes <i>BtabGR1</i> and <i>BtabGR2</i> in <i>Bemisia tabaci</i>  #br#]]> Objective】Bemisia tabaci is an important agricultural and invasive pest worldwide. Although B. tabaci has many host plants, there are differences in the tropism of B. tabaci to these different hosts. The gustatory receptor genes (GRs) play an important role in its feeding selection and other behaviors. In this study, We cloned the two gustatory receptor genes (GR1 and GR2) of Bemisia tabaci, and clarified their expression profiles at different developmental stages and adult tissues, so as to provide a theoretical basis for further functional study of the two gustatory receptor genes.【Method】The gustatory receptor genes were screened from the adult head transcriptome of B. tabaci. The open reading frame (ORF) of two gustatory receptor genes was cloned by nest PCR, and the two genes were named BtabGR1 and BtabGR2, respectively. Encoded amino acid sequence features and structure characteristics of the two genes were analyzed by multiple bioinformatics methods. Phylogenetic tree between BtabGR1, BtabGR2 and other Hemiptera insects GRs was constructed using neighbor-joining. The expression levels of the two genes at different developmental stages (egg, 1-4 instar larva, female and male adults), different adult tissues (head, thorax, abdomen, leg) were detected by qRT-PCR.【Result】 The cDNA sequences of BtabGR1 and BtabGR2 (GenBank accession number: OL845904 and OL845905) were obtained. The complete ORFs of these two genes are 1 287 and 1 344 bp in length, encoding 428 and 434 amino acids with the predicted molecular weight of 48.54 and 51.50 kD, the isoelectric point of 8.85 and 8.74, 4 and 6 transmembrane domains. Amino acid sequence alignment and phylogenetic analysis showed that BtabGR1 and BtabGR2 were closely related to the GR28b and GR43a-like of other Hemiptera insects. Developmental stages expression results showed that BtabGR1 and BtabGR2 were expressed in various developmental stages of B. tabaci. The expression levels of BtabGR1 in female and male adults were higher than those in other developmental stages, while BtabGR2 was highly expressed in the egg. Tissue expression results showed that BtabGR1 and BtabGR2 were expressed in different tissues of adult B. tabaci, and two genes were both highly expressed in the head of adults. 【Conclusion】The cloning of the full-length ORF gustatory receptor genes BtabGR1 and BtabGR2 from B. tabaci MED, having the typical characteristics of insect gustatory receptor genes, and their expression profiles provide a basis for future functional study.]]> <![CDATA[Cloning and function analysis of a serine protease inhibitor gene <i>Nlserpin2</i> in the <i>Nilaparvata lugens</i> #br#]]> Objective】The aim of this study is to clone a serine protease inhibitor gene Nlserpin2 and clarify its expression patterns and biological functions in the brown planthopper (BPH), Nilaparvata lugens.【Method】Based on the transcriptome data of BPH, the full-length cDNA of Nlserpin2 was cloned by PCR, and its nucleotide and protein sequences were subsequently characterized using bioinformatics tools. The expression patterns of Nlserpin2 in different developmental stages, different tissues and in response to an entomopathogenic fungus Metarhizium anisopliae were determined by qRT-PCR. The target gene Nlserpin2 was further silenced by RNAi, and the surviaval rate and the changes in the resistance to the M.anisopliae infection of BPH were determined by bioassay.【Result】The Nlserpin2 (GenBank accession number: KC355239) was successfully cloned from BPH. The open reading frame (ORF) is 1 209 bp in length, encoding 402 amino acids with a conserved serpin domain and a reactive center loop (RCL) that typically existed in the members of the serpin superfamily. A signal peptide consisting of 27 amino acid residues was also predicted at the N-terminus. The phylogenetic analysis showed that Nlserpin2 is clustered together with other hemipteran Nlserpin2, and has the highest homology with Sogatella furcifera serpin. The qRT-PCR results showed that the expression of Nlserpin2 had obvious temporospatial characteristics. The lowest and highest expression levels were observed in the 3rd nymphs and the male adults, respectively. The transcript level of Nlserpin2 in the gut was significantly higher than that in the fat body and ovary. The expression of Nlserpin2 in BPH was significantly upregulated at 2 and 3 days post infection with M. anisopliae. RNAi results showed that the expression levels of Nlserpin2 could be significantly inhibited by microinjection of dsNlserpin2. Inhibition of Nlserpin2 expression caused significantly decreased in the survival rate and the capability to resist M. anisopliae infection of the 5th instar nymphs of BPH. 【Conclusion】Nlserpin2 plays important roles in the growth, development and pathogen defense of BPH, which can be used as a potential target for RNAi-mediated control of BPH and provided the gene of interest for genetic improvement of entomopathogenic fungi with a hypervirulent to BPH.


]]> <![CDATA[Colistin Promotes <i>mcr-1</i>-positive IncI2 Plasmid Conjugation Between <i>Escherichia coli</i> #br#]]> Background】Colistin is a last line antibiotic for the treatment of clinical infections caused by multi-drug resistant Gram-negative bacteria, and it has also been extensively used in animal industry as a feed additive and therapeutic drug. In 2015, Chinese researchers discovered the plasmid-mediated colistin resistance gene mcr-1, indicating that this last defense line is at risk of being breached. However, the effect of bactericidal concentration and sub-inhibitory concentration of colistin on the transmission of mcr-1-positive plasmid is still unknown. 【Objective】This study used the most prevalent mcr-1-positive plasmid IncI2 as an object to explore the influence on the conjugative transfer frequency under different colistin concentrations. 【Method】The conjugation experiment under different colistin concentrations (0.02–4 μg·mL-1) was carried out by broth method. Real time quantitative PCR and the constructed formula were used to calculate the conjugative transfer frequency at different timepoints (1–24 h), and also different colistin concentrations. The cell membrane permeability and ROS production of donor and recipient bacteria under different colistin concentrations were detected using PI dye and reactive oxygen species (ROS) detection kit, respectively. Colistin negative group and the three treatment groups (0.02, 1, 4 μg·mL-1) were subjected to RNA sequencing as control, low, medium and high concentration groups respectively, and gene differential expression was analyzed by Deseq2 software. All statistical analysis were conducted by Prism v8.2.0 software. 【Result】We established a formula to calculate the conjugative frequency in our study, and found that the bactericidal concentration (4 μg·mL-1) of colistin significantly increased the conjugative transfer frequency of mcr-1-positive IncI2 plasmid by 3-10 times at different timepoints, whilst no significant difference on other concentrations. Transcriptome results showed that when compared to control group, the expression of genes related to type IV secretion system (T4SS) in IncI2 plasmid, including virB1, virB2, virB5 and traC were significantly increased in all colistin concentrations groups. In addition, the expressional level of type I fimbrium biosynthesis genes were significantly increased in all colistin groups. PI staining results showed that 2 μg/mL and 4 μg/mL colistin could elevate the cell membrane permeability in donor and recipient bacteria, and coincidently transcriptome results showed that the expressional levels of membrane-related genes including ompAX, bamDE, lolB, yiaD, csgEF were significantly up-regulated. However, ROS production and expressional level of related genes were not significantly increased after colistin treatment. 【Conclusion】This study revealed that colistin promotes the conjugative transfer frequency of mcr-1-positive IncI2 plasmid between E. coli by increasing the activity of bacterial T4SS, cell membrane permeability and pilus formation, suggesting the bactericidal concentration of colistin could increase the plasmid transmission in all survived mcr-1-positive E. coli. Therefore, the therapeutic use of colistin in animals may maintain the existence and transmission of mcr-1-positive plasmids. In addition, since colistin has been approved for clinical use in human medicine, this phenomenon may lead to the failure on colistin treatment for mcr-1-positive pathogens.


]]> <![CDATA[Analysis of the recommended dosage of insecticides registered on small insects of fruits and vegetables in China]]> based on the analysis of insecticides registered on small insects of fruits and vegetables in China.【Method】The information of insecticides registered on China Pesticide Registration Information Website for controlling ten kinds of major small insects, tobacco whitefly, greenhouse whitefly, thrip, spider mite, aphid, coccid, leaf miner, striped flea beetle, psyllid, and rust mite, in the fields of fruits and vegetables in China were inquired on June 30, 2020. In this paper, the quantity of single insecticides and mixtures registered on small insects of fruits and vegetables were analyzed, and the quantity of single herbicides and formulations were also analyzed. Moreover, the active ingredients with high dosages were selected and analyzed in terms of formulation and control target. Finally, six active ingredients, five crops and five control targets with the largest dosage were selected as possible combinations for further analysis.【Result】Entries of insecticides registered for controlling aphid and spider mite were significantly more than the other small insects; the five highest dosage, mean dosage and dosage range of single insecticides were as followed: spider mite, coccid, aphid, greenhouse whitefly, and rust mite; 15 active ingredients with high dosages were selected and the potential problems, large recommended dosage differences and abnormal high value points, were found in lime sulfur, dinotefuran, azocyclotin, imidacloprid, dichlorvos, and sodium pimaric acid; a higher active ingredient dosage of single insecticides was observed in the formulation of crystallization (powder), aqueous solution, water soluble powder, emulsion, smoke generator, and granule and for the crops of apple trees, citrus trees, cucumber (protected field), cucumber and cruciferous vegetables. There were obvious problems, large recommended dosage differences and abnormal high value points in the combinations of azocyclotin-citrus trees-spider mite and lime sulfur- apple trees-spider mite, which were attributed to the differences of formulations and companies.【Conclusion】In order to reduce the dosage of insecticides and slow down the development of small insect resistance to insecticides, it is suggested that insecticide varieties with abnormal high dosages of active ingredients should be reduced for registration and the high efficiency and low risk insecticide varieties with lower dosages of active ingredients will be recommended based on the study of the minimum effective dose of insecticides.


]]> <![CDATA[Cuticle protein genes <i>TcCP14.6</i> and <i>TcLCPA3A</i> are involved in phosphine resistance of <i>Tribolium castaneum</i><i></i> #br#]]> Objective】Cuticle proteins (CPs) are the main components of insect cuticle, and numerous studies have confirmed that the CP genes were involved in insecticide resistance. The present study was conducted to clarify the roles of TcCP14.6 (cuticle protein CP14.6) and TcLCPA3A (larval cuticle protein A3A) in phosphine resistance of Tribolium castaneum.【Method】The FAO-recommended bioassay method was used to determine the phosphine resistance levels of five different T. castaneum populations. The TcCP14.6 and TcLCPA3A sequences were downloaded from the T. castaneum genome data, and their encoded amino acid sequences, signal peptides and conserved domains were predicted via the online services. Additionally, the total RNAs were extracted from different tissues (the cuticles of head, chest and abdomen, wing, foot, gut, malpighian tubules and fat body), different phosphine resistance levels, as well as phosphine induction of T. castaneum respectively. Then, with TcRPS and TcRPL as internal reference genes, the RT-qPCR was used to analyze the expression patterns of TcCP14.6 and TcLCPA3A genes in different tissues, different phosphine resistance levels, and their expression profiles under phosphine induction. Lastly, the RNA interference (RNAi) technology was used to explore the relationship between two CP genes and phosphine resistance in T. castaneum. 【Result】 The bioassay analysis showed that Jiangsu (JS, RR=1.7) and Yunnan (YN, RR=3.0) belonged to susceptible populations, Hunan (HN, RR=20.2) belonged to moderately resistant population, Sichuan (SC, RR=395.4) and Guangdong (GD, RR=862.7) belonged to highly resistant populations. The sequence analysis demonstrated that both TcCP14.6 and TcLCPA3A proteins consisted of signal peptides and chitin binding domains. The RT-qPCR analysis suggested that TcCP14.6 and TcLCPA3A genes all had a higher expression in the peripheral tissues (the cuticles of head, chest and abdomen, wings and foot) of T. castaneum, and with a lower expression in the internal tissues, such as fat body, gut and malpighian tube. Besides, with the increase of phosphine resistance levels in T. castaneum, the TcCP14.6 increased and TcLCPA3A decreased their expression levels respectively. The expression levels of TcCP14.6 and TcLCPA3A genes were significantly increased and decreased respectively after phosphine induction for 6 h in T. castaneum. The injection of dsRNA could significantly inhibite the expression of TcCP14.6 and TcLCPA3A genes in phosphine resistance (GD) and susceptible (YN) populations of T. castaneum. When treated with phosphine (LC30), the insect mortality was significantly increased after the TcCP14.6 was silenced. Instead, the insect mortality was significantly decreased after the TcLCPA3A was knocked down.【Conclusion】The two CP genes TcCP14.6 and TcLCPA3A are involved in phosphine resistance of T. castaneum.


]]> <![CDATA[Effect of Different Rootstocks on the Flavonoids of <em>Vitis vinifera</em> L. cv. Tannat Grape Fruits]]> Objective】Flavonoids are important metabolites of wine grapes, which have important effects on the qualities of the grape fruits and their wines. In this study, the effects of different rootstocks on the physicochemical parameters and flavonoid substances of Tannat (Vitis vinifera L. cv.) grapes were studied to provide the theoretical basis for the selection and utilization of rootstocks.【Method】In the present research, Tannat shoots were used as scions and were greenwood grafted on four different kinds of rootstocks, including 1103P, 101-14, SO4 and Beta. On the bases of the analysis of the basic physicochemical parameters ( total soluble solid content, titratable acid, pH, 100-berry weights) of the commercial mature grape berries of these grapevines grafted on different rootstocks, the compositions and contents of the flavonoids in the corresponding grape berries were detected by using high performance liquid chromatography-mass spectrometry (HPLC-MS), in the three vintages of 2016, 2017 and 2019.【Result】 The results showed that rootstocks had little effect on the 100-berry weights of the Tannat grapes; the contents of the total soluble solids were higher in the combination of Tannat/101-14, as well as the own-rooted Tannat; the titratable acids of the grape juice of the Tannat/101-14 and the Tannat/Beta combinations were higher than the own-rooted Tannat grapes. In the part of flavonoids, the contents of anthocyanins and flavonols in the Tannat/SO4 combination was the lowest in all of these combinations; the contents of anthocyanins and flavonols in the Tannt/101-14 combination and the own-rooted Tannat were higher than those of other combinations; the content of flavanols in the skins of the Tannat/101-14 combination was higher. In addition, the contents of anthocyanins and flavonols in the Tannt/11103P combination was lower, but the contents of flavanols in the skins of the Tannat/1103P combination was relatively high. Besides, the results of two-factor ANOVA of the year and the rootstock showed that rootstocks had significant effects on all types of anthocyanins. All the four rootstocks showed a tendency to reduce the anthocyanins of peonidin, petunitin, malvidin, non-acylation, acetylation and coumaric acylation. In the mature fruits, quercetins were the most abundant flavonols, followed by myricetins, while syringetins and laricitrins accounted for a smaller proportion. Rootstocks had a significant effect on the myricetins and laricitrins, which reduced the contents of myricetin and laricitrin to different degrees. Through the establishment of OPLS-DA (Orthogonal Partial Least Squares Discrimination Analysis) model, we found that the Tannat/101-14 combination was mainly distinguished by the malvidin anthocyanin compared with the own-rooted grapes. The main difference compounds of Tannat/Beta combination were anthocyanins of malvidin, delphinidin and acetylation, the total flavanols and quercetin compounds. The difference compounds of the Tannat/SO4 combination were anthocyanins of malvidin, delphinidin, acetylation, and the quercetins. The Tannat/1103P combination mainly consists of acetylated anthocyanins and quercetins.【Conclusion】 In Beijing region, all the four rootstocks (1103P, SO4, Beta, 101-14) showed a tendency to reduce the flavonoid contents, including anthocyanins of peonidin, petunitin, malvidin, non-acylation, acetylation, coumaric acylation quercetins and laricitrins. The rootstock '101-14' was beneficial to the accumulation of anthocyanins, flavonols and flavanols in fruit skins, which was conducive to the improvement of the wine quality, so it was recommended to be used. However, Tannat grapes grafted with SO4 had less flavonoid accumulation and was not recommended to be used.


]]> <![CDATA[Effects of lncFAM200B on the Lipid Deposition in Intramuscular Preadipocytes of Yak]]> Objective】The aim of this study was to analysis the effects of lncFAM200B in the lipid deposition in intramuscular preadipocytes of yak, which laid a foundation for further mechanism research. 【Method】The longissimus dorsi muscle tissue of yak was collected and used to separate intramuscular preadipocytes; The adenovirus mediated overexpression technology was used to realize the overexpression of lncFAM200B, and the siRNA interference and the siRNA interference technologies were used to analyze the function of lncFAM200B. The mRNA expression level of fat differentiation marker (PPARγ, C/EBPα and AP2) and the potential target (SIRT1 and PTEN ) genes of lncFAM200B were detected via real-time fluorescent quantitative PCR (RT-qPCR). Oil red O staining, triacylglycerol (TAG) determination and CCK-8 determination methods were used to detect intracellular lipid droplet deposition and preadipocyte proliferation.【Result】The results showed that overexpression of lncFAM200B not only significantly increased the fat differentiation genes (C/EBPα and AP2, P <0.05) expression level but also increased the lipid droplets deposition with large lipid droplets in the cells during induced differentiation. Conversely, lncFAM200B interference reduced the expression of PPARγ, C/EBPα and AP2 (P <0.05), and lipid droplet deposition. Furthermore, the triacylglycerol content was significantly higher than that of the control group (P <0.05) after lncFAM200B overexpression 4 days, but lower after siRNA interference 6 days. Moreover, the SIRT1 levels increased with time was first decreased and then increased trend, and the PTEN have the opposite trend during lncFAM200B overexpression, and the opposite results of the two genes obtained during lncFAM200B interference. In addition, the results of CCK-8 experiment showed that there was a significant difference in cell proliferation activity both in overexpression or interference group after 72 hours. 【Conclusion】Taken together, our results showed that lncFAM200B regulates yak adipose differentiation by influence the expression of fat differentiation marker (C/EBPα and AP2), and further affect the triacylglycerol content and the lipid droplet deposition, but the detail mechanism need to be further research efforts.


]]> <![CDATA[Effects of Non-Starch Polysaccharide Enzymes Cocktail of Corn-Miscellaneous Meal-Based Diet Optimized by In Vitro Method on Intestinal Microbiome of Finishing Pigs]]> Objective】 The objective of this study was to optimize the non-starch polysaccharide (NSP) enzymes cocktail of the corn-miscellaneous meal-based diet for finishing pigs by using in vitro simulation method, and to analyze the effects of the optimal NSP enzymes cocktail (OEC) on dietary nutrient digestibility and intestinal microbial composition and structure of finishing pigs, so as to provide data support and theoretical reference for efficient utilization of diets and precise feeding. 【Method】 In experiment 1, six NSP enzymes (xylanase, β-glucanase, cellulase, α-galactosidase, β-mannanase and pectinase) were added to the corn-miscellaneous meal-based diet of finishing pigs, respectively, and in vitro ileal dry matter digestibility (IVIDMD) was determined by gastric-small intestinal simulation digestion method in vitro. When IVIDMD reached the maximum, the supplemental level of each NSP enzyme was the coding level of NSP enzyme 0. In vitro digestion experiments were carried out according to the six-element quadratic regression orthogonal rotation combination design. The optimal NSP enzymes cocktail (OEC) of the corn-miscellaneous meal-based diet was selected by establishing the six-element quadratic regression equation between IVIDMD and the supplemental level of NSP enzymes. The in vitro dry matter digestibility (IVDMD), in vitro gross energy digestibility (IVGED) and in vitro digestible energy (IVDE) of diets before and after OEC addition were determined by gastric-small intestinal-large intestinal simulation digestion method in vitro in order to verify the effect of OEC. In experiment 2, 16 healthy castrated barrows (117.8 ± 1.66 kg) with similar body weight were randomly divided into two groups with eight pigs in each group. The pigs in the control group were fed the corn-miscellaneous meal-based diet, and the pigs in the enzyme-addition group were fed the basal diet supplemented with OEC. On the 18th day of the experiment, fresh feces of pigs were collected by rectal wiping method, and the diversity and relative abundance of fecal microbiome were analyzed by high-throughput sequencing analysis of 16S rRNA gene, and the function was predicted. 【Result】 The results showed as follows: 1) Under the conditions of this experiment, the optimized NSP enzymes cocktail of corn-miscellaneous meal-based diet was as follows: cellulase 1,003 U/kg, xylanase 18,076 U/kg, β-glucanase 1,377 U/kg, β-mannanase 14,765 U/kg, α-galactosidase 337 U/kg, and pectinase 138 U/kg; 2) Adding NSP enzymes cocktail optimized by in vitro method in corn-miscellaneous meal-based diet significantly increased the IVDMD from 73.44% to 76.26% (P < 0.01), the IVGED from 74.03% to 76.45% (P = 0.01), and the IVDE from 14.97 MJ/kg to 15.58 MJ/kg (P < 0.01); 3) At the phylum level, a total of 12 phyla with relative abundance greater than 0.1% were selected, among which Bacteroidetes, Firmicutes, and Spirochetes were the dominant phyla, and the sum of the three phyla accounted for more than 96% in the group; 4) At the genus level, adding OEC in the diet significantly increased the relative abundance of Norank_F_F082, Norank_F_Bacteroidales_RF16_group, Bacteroides and Roseburia (P < 0.05), Eubacterium_ruminantium_group (P = 0.083) had an increasing trend, while the relative abundance of Oscillibacter decreased significantly (P < 0.05), Clostridium_Sensu_Stricto_1 and Norank_F__Norank_O__WCHB1-41 (P = 0.083) showed a decreasing trend (P = 0.052). 【Conclusion】 Dietary non-starch polysaccharide enzymes cocktail optimized by in vitro method increased in vitro digestibility of dry matter and energy and in vitro digestible energy of corn-miscellaneous meal-based diets for finishing pigs, increased the proportion of beneficial bacteria such as fiber decompose bacteria and butyric acid producing bacteria in intestinal microorganism of finishing pigs, reduced the number of harmful bacteria to a certain extent, and optimized intestinal microecology.


]]> <![CDATA[Co-expression Network and Transcriptional Regulation Analysis of SO<sub>2</sub>-induced Postharvest Abscission of ‘Kyoho’ Grape]]> 2) treatment can effectively prevent Botrytis cinerea and postharvest decay, but it can lead to grape berry abscission. The purpose of this study was to clarify the key genes and transcriptional regulation mechanism. 【Method】After grapes were treated with SO2, the grape berry abscission rates of CK control group and SO2 treatment group were collected at 2, 4 and 6 days, respectively. Samples of ‘Kyoho’ grapes in CK control and SO2-treated were sequenced by high-throughput sequencing technique. The grape genome was used as the reference genome for sequence alignment, and the gene expression was calculated by TPM algorithm. The transcriptome data were systematically analyzed by gene set enrichment analysis (GSEA), gene co-expression network (GCN) and transcription regulation network prediction, and the expression was verified using quantitative real-time fluorescence PCR (qRT-PCR). 【Result】SO2 treatment could significantly induced grape berry abscission, which was significantly higher than that of the control (9.88%) at 2 d. The abscission rate reached 38.25% at 6 d compared to 11.85% in the control. Transcriptome analysis based on the annotated information of GO and KEGG databases and analyzed by GSEA software, it was found that SO2-induced grape berry abscission involves plant hormone signal transduction, cell wall metabolism, glucose metabolism, phenylalanine metabolism, energy metabolism and other pathways. GCN divided the leading genes in GSEA analysis into 12 levels. Level 4 ~ 9 were enriched in energy metabolism and glucose metabolism-related pathways, level 4 was enriched in hormone response and oxidative stress response. The transcriptional regulation prediction analysis of transcriptional regulation of GCN key level gene promoter sequences showed that there were 987 pairs of regulatory relationships among 95 transcription factors (TFs). WRKY14, WOX8, KUA1 continued to be downregulated under SO2 treatment. MYB60, MYB73, ANL2, ERF2, DOF3.6, GATA25, WRKY57, KAN2, ATHB6 continued to be upregulated under SO2 treatment. In addition, MYB15, WRKY11, WRKY33, WRKY40, WRK75 were first adjusted upwards and then downwards. Mapping the transcriptional regulatory networks of ERF2, MYB60 and WRKY40 revealed that the regulated target genes were involved in cell wall metabolism, sugar metabolism and other related pathways. The qRT-PCR results showed that PME36 and ERF2 had similar up-regulated expression trends, GAUT7, MYB60 and UGE3 had similar up-regulated expression trends, in addition WRKY40 was induced to be up-regulated at 2 and 4 d of SO2 treatment, PPME1 and COMT1 expression was consistently down-regulated, and LAC15 was significantly induced to be up-regulated at 4 d of SO2.【Conclusion】SO2-induced the expression of genes related to nutrient metabolism, energy metabolism and cell wall metabolism pathway, which was regulated by a variety of transcription factors, and eventually led to the grape berry abscission.


]]> <![CDATA[Cloning and Characterization of Alternative Splice Variants of LsPHYB in Lettuce Under Heat Stress]]> Objective】Phytochrome B (PHYB) is a receptor for both light and temperature. The biological functions of alternative splice variants of LsPHYB in lettuce in response to high environmental temperatures were investigated through cloning them and analyzing their expression patterns in order to provide a theoretical basis for breeding heat-tolerant lettuce.【Method】The cDNA sequences of LsPHYB were searched from the genomic database of lettuce by bioinformatics method. The cloned LsPHYB1, LsPHYB2 and LsPHYB3 were subjected to multi-sequence alignment, alternative splice variants form analysis and phylogenetic analysis. Protein properties, such as molecular weight, theoretical isoelectric point, hydrophilicity and hydrophobicity, were predicted by online software. Secondary structure, tertiary structure and conserved domains were analyzed by bioinformatics software. Three alternative splice variants were characterized for expression after high temperature treatment assayed by RT-PCR. 【Result】There were three alternative splice variants of LsPHYB obtained by cloning, namely LsPHYB1, LsPHYB2 and LsPHYB3, with their CDS lengths of 3 509, 3 877 and 2 690 bp, which encoded 1 094, 960 and 853 amino acids, respectively. Alternative splice forms of LsPHYB1 were alternative 3′ splice site and skipped exon. Alternative splice forms of LsPHYB2 were alternative polyA and retain intron. An alternative splice form of LsPHYB3 was skipped exon. Conserved structural domain analysis showed that the N-terminal of PHYB2 lacked the PAS and PHY domains. The N-terminal of PHYB3 lacked the PAS and PHY domains, and its C-terminal lacked the HisKA domain. Phylogenetic analysis showed that three alternative splice variants were clustered into a clade. qRT-PCR analysis showed that the expression of LsPHYB3 was highest at the first day of high temperature treatment; LsPHYB2 had higher expression than LsPHYB1 and LsPHYB3 at days 5-9 of high temperature treatment; and at day 11 of high temperature treatment, the expression of LsPHYB1 was higher than that of LsPHYB2 and LsPHYB3. The three alternative splice variants peaked at different times during the 11 days of high temperature treatment. 【Conclusion】There are three alternative transcript variants of LsPHYB, named LsPHYB1, LsPHYB2 and LsPHYB3. LsPHYB1 encodes PHYB1 with intact functional domains; LsPHYB2 encodes a truncated PHYB2 without PAS and PHY domains; LsPHYB3 encodes a truncated PHYB3 without PAS, PHY and HisKA domains. LsPHYB3 expression was highest in the early stage of high temperature treatment, LsPHYB2 in the middle stage, and LsPHYB1 in the late stage, suggesting that the three alternative splice variants are functionally differentiated in response to high temperature stress.


]]> <![CDATA[Effect of CO<sub>2</sub> Like Fertilization on Rice Growth by HCO<sub>3</sub><sup>-</sup> in Biogas Slurry #br#]]> 3-. The conversion of HCO3- in biogas slurry and its effect on rice growth were investigated in order to provide a new theoretical basis for replacing chemical fertilizer with biogas slurry, reducing the amount of chemical fertilizer and whether biogas slurry can be utilized as resources. 【Method】Four treatments, biogas slurry (BS), biogas slurry (BS?B), deionized water plus HCO3- (W+B) and deionized water (W), were set up in this paper. Using 13C labeling technology, the characteristics of CO2 release were observed through pot experiment at Rice Seedling Stage, and the photosynthetic rate, intercellular CO2 concentration, dry and fresh weight, plant height, overlying water and soil pH, HCO3- and NH4+ contents, were analyzed. 【Result】(1) Under BS treatment, CO2 release rates ranged from 9.55-38.07 mg·kg-1·h-1, with a net cumulative release of 4654.06 mg·kg-1. Under BS?B treatment, the CO2 release rates ranged from 4.55-17.25 mg·kg-1·h-1, and the net cumulative release was 780.68 mg·kg-1. Under W+B treatment, the CO2 release rate was 3.93-26.33 mg·kg-1·h-1, and the net cumulative release was 1274.07 mg·kg-1. Under W treatment, the CO2 release rate was 3.22-11.90 mg·kg-1·h-1, and the cumulative release amount was 2265.20 mg·kg-1. Under BS treatment, the average CO2 release rate was 4.18 times and 2.44 times of BS?B and W+B, respectively, and the net cumulative CO2 release was 5.96 times and 3.65 times of BS?B and W+B, respectively, which were significantly higher than those under BS?B and W+B treatments. At the same time, the net cumulative release under BS treatment was greater than the sum of the two treatments (BS?B) + (W+B), and HCO3- had a synergistic effect with other components in biogas slurry on CO2 release. (2) The net cumulative release of 13CO2 under BS treatment was 32.87 mg·kg-1, accounted for 0.71% of the net cumulative release of CO2 in soil-rice system. The net cumulative release of 13CO2 under W+B treatment was 13.18 mg·kg-1. In comparison, the net cumulative release amount of 13CO2 under BS treatment was significantly higher than that under W+B treatment (P<0.05), indicated that other components in biogas slurry promoted the conversion of HCO3- to CO2. (3) The net photosynthetic rate of BS and BS?B treatments in the first 12 h was significantly higher than that of W+B and W treatments. After the addition of culture medium, the net photosynthetic rate under BS treatment was significantly higher than that under BS?B treatment at 2-7 d, and was significantly higher than that under W+B treatment during the whole culture period (P<0.05). HCO3- in biogas slurry significantly improved the photosynthesis of rice leaves. In comparison, the intercellular CO2 concentration was significantly lower than that of the other three treatments 5 days before BS treatment. Rice plant height and fresh weight under BS and BS-B treatments were significantly higher than those under W+B and W treatments (P<0.05), and there was no significant difference in dry weight among the four treatments. (4) The fixed 13CO2 content of rice seedlings treated by BS was 4.05 g·kg-1, and the utilization rate of marker HCO3- was 18.54%. The fixed amount of 13CO2 in W+B treatment was 3.29 g·kg-1 and the H13CO3- utilization rate was 14.20%. The 13CO2 of H13CO3- promoted the photosynthesis of rice and was beneficial to the growth of rice. (5) The release rates of CO2 and 13CO2 under BS and W+B treatments were significantly correlated with overlying water and soil HCO3- content and pH. At the same time, the photosynthetic rate of rice under BS and W+B treatments was significantly positively correlated with HCO3- content in soil. 【Conclusion】When biogas slurry was returned to the field, a large amount of HCO3- transformation significantly promoted the release of CO2, which was beneficial to rice photosynthesis. Soil HCO3- content and soil pH value are important factors affected CO2 release and rice photosynthesis. At the same time, rice had a higher utilization rate of HCO3- in biogas slurry, and HCO3- in biogas slurry had obvious CO2-like fertilization effect.


]]> <![CDATA[The role of Linoleyl ethanolamide in tomato defense against <i>Botrytis cinerea</i>]]> Background】Gray mold is one of the important diseases of tomato and causes significant yield losses up to 20%-40%. Nowadays, chemical control are often used in tomato production, which is effective but increases the risk of agricultural products safety and results in environmental pollution. N-acylethanolamines (NAEs) are a kind of lipid bioactive compounds naturally occurring in plants, which have been identified to have a variety of immune functions in mammals, however, their role in plant immunity is still unknown.【Objective】Thus, investigating the effects of NAEs on tomato plant defense against gray mold infection is undoubtedly of great significance for regulation of tomato resistance to gray mold.【Method】In this study, tomato ‘Moneymaker’ plants were infected by Botrytis cinerea with or without exogenous NAE 18:0, NAE 18:2, NAE 22:5, and then photosynthetic characteristics and the B. cinerea growth were measured. To reveal the underlying mechanism of NAE 18:2 induced plant resistance to B. cinerea, Fluorescence parameters of tomato leaves, transcript abundance of defense-related genes (e.g. PII, PR1, NPR1, Nr, ACO1, PYR1a), and contents of plant hormones (e.g. JA, SA, ETH, ABA, IAA) were measured. Furthermore, ethylene-insensitive mutant was employed to verify the function of NAE 18:2.【Result】The growth of B. cinerea was not affected by exogenous NAEs treatment during in vitro culture. The photosystem II photochemical efficiency (ΦPSII) of tomato significantly decreased under B. cinerea infection. However, exogenous NAEs treatment was able to enhance the ΦPSII, and NAE 18:2 has the best effect on tomato plant defense against B. cinerea, which reduced the disease index to 1.3 and the actin gene transcript level of B. cinerea by 60%. The expressions of PR1 and NPR1 could be induced by B. cinerea infection but not by NAE 18:2 treament. However, the expressions of PII, Nr and ACO1 were up-regulated when plants were pre-treated by NAE 18:2 before B. cinerea infection, the ACO1 was significantly higher than PII, Nr. Compared to the control, the contents of SA , JA, IAA and ETH in the leaves were increased significantly after B. cinerea infection, while only the contents of ETH were further increased when pre-treated by NAE 18:2. Moreover, exogenous NAE 18:2 pre-treatmetn could not improve the defense against B. cinerea in the ETH-insensitive mutant nr.【Conclusion】Exogenous NAE18:2 treatment can increase leaf photosynthesis, transcript abundance of defense-related genes, and the contents of plant hormones. It can also improve the resisitance of tomato plants to B. cinerea, which may depend on the ETH signaling pathway.

]]> <![CDATA[Comprehensive Evaluation of Phenotypic Characters of Nature Population in Upland Cotton]]> Objective】To analyze the fiber quality, yield, and early maturity of Upland cotton germplasm, screen the evaluation indicators comprehensively, establish a reliable evaluation model, and provide theoretical support for developing new Upland cotton varieties.【Method】 A total of 630 Upland cotton accessions selected from various sources were used to investigate 17 traits in 8 environments in three major cotton-growing regions in China. The best linear unbiased prediction (BLUP) was estimated for phenotypic traits by utilizing R package "lme4" and used for further analysis, including correlation analysis, principal component analysis, affiliation function method, cluster analysis and stepwise regression to evaluate population characteristics.【Result】This upland cotton population had high genetic diversity with a diversity index ranging from 1.961 to 2.084, and significant regional specificity existed. The boll number, fiber elongation, spinning consistent index, and short fiber index of this population had considerable variation, while that of fiber length, fiber strength, and growth period traits was lower. Correlation analysis showed significant or highly significant correlations among most traits, and there was a strong correlation among some fiber quality traits. The 17 traits were converted into 6 independent composite indices through principal component analysis with a contribution range of 5.860%-31.044% and a cumulative contribution of 82.642%. Principal component analysis can classify the fiber quality traits, yield traits and agronomic traits in this upland cotton population. The comprehensive evaluation value (F value) of phenotypes was calculated using the affiliation function method, the phenotypes of 17 traits were all significantly correlated with F values. The result demonstrated that the accessions with high F values (mean value of 0.668) had significantly higher yield traits (boll number, boll weight, lint percentage, and seed index), fiber quality traits (fiber length, fiber length uniformity, fiber strength, spinning consistent index, and short fiber index), plant height and fertility traits than those with low F values (mean value of 0.396). Regression equations for eight traits (boll number, boll open date, boll weight, flowering date, lint percentage, plant height, sympodial brand node, and spinning consistent index) as independent variables were established using stepwise regression. Based on the F value, the 630 germplasm were clustered into four categories, the first category was the high-quality fiber type, containing 118 accessions; the second category was the high-yield type, comprising 250 accessions; the third category was the early-maturing type, comprising 51 accessions; the characteristics of the fourth category was between the second and third categories. Finally, 23 better fiber quality and 135 high-yield germplasms were selected for breeding and production.【Conclusion】The phenotypic traits of Upland cotton are geographically specific; it is feasible to use multivariate statistical analysis to comprehensively evaluate Upland cotton germplasm; the whole population can be classified into four categories (high-quality, high-yield, early maturity and other types).


]]> <![CDATA[Evaluation of blast resistance and genetic structure analysis of rice germplasm in Heilongjiang Province]]> Objective】Rice blast seriously threatens rice production in Heilongjiang Province and the breeding and utilization of anti-blast varieties are the most economical, safe and effective measures to control it. This study explored the resistance of rice varieties in Heilongjiang Province; clarified the resistance effect of disease resistance genes, and provided a basis for the selection and utilization of germplasm resources of rice blast in Heilongjiang Province. 【Method】In the autumn of 2018,134 monospore rice strains were collected from the main rice area in Heilongjiang Province, and the resistance of 50 dominant rice varieties was analyzed. For the reported 35 rice blast resistance genes, a comparison was made between the varieties and positive control varieties. Sequencing results of some positive control varieties were compared with the reference sequence published in the National Centre for Biotechnology Information（https://www.ncbi.nlm.nih.gov/） to analyze the existence of rice blast resistance genes in the corresponding varieties. Through the correlation analysis of gene aggregation type and breed resistance performance, the genotypes related to the resistance performance of rice varieties in Heilongjiang Province were clarified. 【Results】Among 50 rice varieties in Heilongjiang Province, Longgeng 20 had the best resistance (R). Longgeng 67, Longken 202, Longgeng 40, Longgeng 31, Longgeng 57 and Longgeng 43 had moderate disease resistance; whereas, 43 varieties such as Jiahe 1 had relatively low resistance. Through the analysis of variety combination resistance, we found that 33 pairs of Longgeng 20 + Longgeng 67 had a high RAC（resistance association coefficient) value, low VAC (virulence association coefficient) value and good combined disease resistance. The matching structure showed potential for application. The identification of resistance genes carried by specific primers showed that Pish, Pi36, Pi33 and Pi-CO39 were detected, and Pi63, Ptr, Pi37, Pi64, pi21, Pi9, Pi54, Pikh, Pia, Pikp, Pi35, Pikm and Pik were between 50–100% of occurences frequency, indicating that such genes were widely used in rice breeding in Heilongjiang Province. The detection rate of Pita, Pib, Pii, Pi5, Piz-t, Pi50 and Pi2 was between 10% and 50%; Pid2 was detected in in two varieties, and Pigm was detected in Jigeng 88. However, Pit, Pid3, Bsr-d1, Pi25, Pid3-A4, Pi56, Pi1, Pike and Pb1 were not detected in the cultivars, indicating that such genes are less distributed in rice varieties in Heilongjiang Province. The variety genotype analysis found that the varieties carried 12–19 resistant genes, with a total of 58 genotypes, indicating that the test varieties had rich blast resistance gene combination types. By analysis, the single gene and gene polymerization with disease resistance showed that the distribution frequency of Pi2, Piz-t, Pi50, Pi5 and Pii corresponded to frequency of resistance. We found that the more varieties carrying resistance genes, the higher the frequency resistance, and six varieties that carrying Pi2+Piz-t+Pi50+α polymerization types showed resistance. 【Conclusion】Our results have demonstrated the following: the resistance of rice germplasm resources in Heilongjiang province is low; combination planting of different varieties could be usefully applied; the distribution of blast resistance genes is different in the participating varieties; Pi2, Piz-t, Pi50, Pi5 and Pii play a leading role in disease resistance, and Pi2+Piz-t+Pi50+α gene polymerization type could contribute to improving rice blast resistance.


]]> <![CDATA[Molecular Mechanism of Regulation by H-NS on IncFⅡ Plasmid Transmission of Multi-drug Resistant Chicken <i>Escherichia coli</i>  #br#]]> IncFⅡ plasmid from a clinically isolated multi-drug resistant Escherichia coli from chicken. The aim is to provide a theoretical basis for controlling the rapid spread of IncFⅡ plasmid mediated multidrug resistance genes.【Method】The growth curves of Escherichia coli ATCC25922 and four recombinant strains (F25922, pBAD25922, FΔhns and FΔhns/phns) were determined to compare the influence of hns on different strains. Conjugation experiments were conducted with F25922, FΔhns and FΔhns/phns as donors and Escherichia coli J53 as recipient, then the conjugation frequency was calculated. The mRNA expression levels of IncFⅡ plasmid conjugation transfer related genes(traM, traJ and traY) in each recombinant strains(F25922, FΔhns and FΔhns/phns) were detected by RT-qPCR. The LacZ reporter strains F25922/PM(PJ/PY), FΔhns/PM(PJ/PY) and FΔhns/phns/PM(PJ/PY) were constructed to determine the β-galactosidase activity of three promoters of tra genes(traM, traJ and traY). The H-NS protein was purified by Ni-NTA resin affinity chromatography. The DNA sequences of three promoters of tra genes were amplified by PCR. The mechanism of H-NS regulating IncFⅡ plasmid transmission was identified by EMSA. And the binding sites of H-NS to different promoters were predicted and further verified by ESMA.【Results】The growth of recombinant strains F25922 and pBAD25922 were not significantly different from that of Escherichia coli ATCC25922, the growth rate of deleted recombinant strain FΔhns and complemented strain FΔhns/phns were significantly lower than that of the control strain F25922. The results showed that the absence of hns could make the adaptability of strains worse, but did not affect the survival of the strains. The results of the conjugation test showed that the conjugation frequency of IncFⅡ plasmid in FΔhns was 1279.33 times higher than that of the control strain F25922(P<0.001), and the FΔhns/phns conjugation frequency of the supplementary strain was significantly lower than that of FΔhns, although it did not completely recover to the level of the control strain F25922. Similarly, the mRNA expression levels of these tra genes(traM, traJ and traY) were significantly higher in the deletion mutant FΔhns. The mRNA expression level of traJ was the highest in FΔhns, which was 1510.14 times that of F25922, followed by traY and traM, which were 448.14 times and 81.54 times that of F25922, respectively. Compared to the deletion strain FΔhns, expression levels of the tra genes(traM, traJ and traY) in the complemented strain FΔhns/phns were significantly decreased. The β-Galactosidase activities of promoters PM, PJ and PY in the reporter strains FΔhns/PM(PJ/PY) were 5.66, 10.45 and 21.91, respectively, which were significantly higher than that of the corresponding promoters of F25922/PM(PJ/PY) (P<0.001). The activities of promoters PM, PJ and PY in the complement reporter strains FΔhns/phns/PM(PJ/PY) were significantly lower than that of FΔhns/PM(PJ/PY), and there was no significant difference with the control strain F25922/PM(PJ/PY). EMSA results showed that H-NS protein could block the DNA migration of three promoters of tra genes, indicating that H-NS could directly bind to the three promoters. By predicting the binding sites and further verified by EMSA, it was confirmed that H-NS protein could bind directly to the AT enrichment region of the promoters of the three genes(traM, traJ and traY).【Conclusion】H-NS protein could bind directly to the AT enrichment region of the promoter region of IncFⅡ plasmid conjugation transfer related genes(traM, traJ and traY), and negatively regulate the conjugation transfer of IncFⅡ plasmid by inhibiting the activity of promoter.

]]> <![CDATA[miR-221-3p regulates ovarian granulosa cells apoptosis by targeting BCL2L11]]> 】BCL2L11 promotes apoptosis in mammals and is involved in the development of tissues and organs related to reproductive traits and in disease treatment. To explore the effect of miR-221-3p on the regulation of granulosa cell apoptosis in Small-Tail Han sheep by targeting BCL2L11, so as to provide evidence for further study of the regulation of BCL2L11 in granulosa cell apoptosis and atresia of follicles. 【Method】Based on the whole transcriptome sequencing analysis of the ovarian tissue of the previous study in our group, the differentially expressed gene BCL2L11 and its regulatory element miR-221-3p were obtained in this study. Analysis of the expression of BCL2L11 in different tissues of the Small-Han Tail sheep using semi-quantitative and tissue fluorescence quantification (RT-qPCR). The expression of BCL2L11 and miRNA-221-3p was identified in the ovarian tissues of the Small-Tail Han sheep in the follicular and luteal phase by RT-qPCR. The miR-221-3p mimic, BCL2L11 wild-type and BCL2L11 mutant-type were co-transfected in HEK293T cells with negative control, the dual luciferase reporter gene detection system was used to determine the targeting relationship between miR-221-3p and BCL2L11. The miR-221-3p mimic and negative control were transfected into ovarian granulosa cells to achieve the overexpression of miR-221-3p. RT-qPCR was used to detect the effect of miR-221-3p on the expression levels of BCL2L11 and the marker genes of the apoptosis of ovarian granulosa cell gene XIAP and Fas at the mRNA level. At the same time, the changes in proliferation of granulocytes in the miR-221-3p overexpression and negative control groups were also analysed using the EdU assay. 【Results】The results showed that the expression of BCL2L11 in ovarian tissue was the highest, followed by spleen and lung tissues. RT-qPCR results showed that the expression of miR-221-3p and BCL2L11 was significantly different in the ovarian tissues of Small Tail Han sheep between follicular and luteal phases, the expression of miR-221-3p was higher in follicular than that in luteal phase ovaries, whereas BCL2L11 was less expressed in follicular than that in luteal phase ovaries, which showed the phenomenon of a negative regulation. Dual luciferase reporter analysis showed that overexpression of miR-221-3p significantly inhibited the activity of BCL2L11 3’UTR vector (P<0.05). The overexpression of miR-221-3p significantly reduced the mRNA level expression of target gene BCL2L11, while follicular granulosa cell apoptosis expression of marker genes XIAP and Fas were also significantly reduced (P<0.05). Analysis of the EdU assay showed that the proliferation rate of granulosa cells overexpressing miR-221-3p was 18.9%, which was significantly higher than that of the negative control group at 10.43% (P<0.01). 【Conclusion】BCL2L11 and miR-221-3p are important genes and regulatory elements that regulate ovarian development in sheep. BCL2L11 is one of the target genes of miR-221-3p, and overexpression of miR-221-3p could inhibit granulosa cell apoptosis by target BCL2L11.



]]> <![CDATA[Knockdown Goat KLF12 to Promote Subcutaneous Adipocytes Differentiation]]> KLF12) is a conserved transcription factor that evolutionarily, and it was found that it could be expressed in a variety of cell types and control a wide range of cellular processes. 【Objective】This study aimed to obtain the coding sequence (CDS) of goat KLF12 gene and to explore its molecular characteristics. Moreover, the study also intended to clarify the expression pattern of KLF12 in goat tissues and subcutaneous adipocytes, and to explore the role of KLF12 in goat subcutaneous preadipocytes differentiation via interference KLF12, so as to provide a theoretical basis for further research on the potential role of KLF12 in the process of fat deposition. 【Method】In this study, the goat KLF12 gene CDS sequence was cloned by Reverse Transcription PCR ( RT-PCR) method, and the nucleotide sequence and amino acid sequence of goat KLF12 were analyzed on online bioinformatics analysis software. The Quantitative Real-time PCR (qRT-PCR) technology was used to detect the expression levels of KLF12 in goat heart, liver, abdominal fat, subcutaneous fat, triceps brachii, longissimus dorsi and other 14 tissues. Furthermore, the expression level of KLF12 in subcutaneous preadipocytes in different differentiation periods was investigated. Then, the goat KLF12 small interfering RNA (si-KLF12) was chemically synthesized and transfected into goat subcutaneous preadipocyte in vitro by using Lipofectamine RNAiMAX transfection reagent. Subsequently, 100μmol?L-1 oleic acid induced adipocyte differentiation. Oil red O and Bodipy staining methods and qRT-PCR techniques were used to clarify the effects of interference KLF12 on the accumulation of lipid droplets in subcutaneous preadipocytes and the mRNA expression levels of adipose differentiation marker genes from the perspectives of morphology and molecular biology. 【Result】The goat KLF12 gene 1315 bp were successfully obtained, which contained an Open Reading Frame (ORF) (1209 bp) and encoded 402 amino acids. The subcellular localization results showed that KLF12 was mainly located in the nucleus. In addition, KLF12 had no transmembrane domain and signal peptide but 3 typical zinc finger domains (ZnF_C2H2) at amino acids 317-341, 347-371 and 377-399. Tissue expression profile showed that the expression level of KLF12 in goats’ heart and spleen were significantly higher than that in other tissues (P <0.01). Moreover, during subcutaneous preadipocytes differentiation, the expression level of KLF12 was peaked at 60 h. After transfection of si-KLF12 into goat subcutaneous preadipocytes, the results of oil red O and Bodipy saining showed that accumulation of lipid droplets in adipocytes were significantly increased. At the same time, the results of qRT-PCR showed that the expression levels of key adipogenic regulatory genes like lipoprotein lipase (LPL) and peroxisome proliferator-activated receptor γ (PPARγ) were significantly increased (P<0.05), while the expression level of preadipocyte growth factor (Pref-1) was extremely significantly reduced (P<0.01). Combined with the morphological observation results and the changes in the expression levels of key adipogenic regulatory genes, it was speculated that KLF12 played a negative regulatory role in the differentiation of subcutaneous adipocytes. 【Conclusion】By investigating the basic molecular biological characteristics and its expression pattern between tissues and cells of goat KLF12 and analyzing the potential regulatory effects of KLF12 on differentiation process of goat subcutaneous adipocytes, the results suggested that KLF12 played a negative role in goats subcutaneous preadipocytes differentiation, and this effect achieved by regulating LPL, PPARγ and Pref-1, which laid a foundation for further exploring the molecular mechanism of KLF12 in regulating the differentiation of adipocytes.

]]> <![CDATA[Analysis on Spatial-Temporal Variation of Cultivated Land]]> Objective】 Soil basic productivity is the cornerstone of realizing high and stable yield for food crops. Defining the temporal change trends and spatial variation characteristics of cultivated land productivity for main food crops can provide important theoretical support for ensuring food security and improving cultivated land quality in China. 【Method】 In this study, based on the national long-term positioning monitoring network of cultivated land quality from 1988 to 2019, we selected the long-term monitoring data of the check area with non-fertilization treatment and the conventional area with farmers' fertilization treatment in the first 3-5 years since the establishment of each monitoring point. The temporal and spatial changes in yield of corn, rice and wheat and soil productivity contribution rates were analyzed in China. 【Result】 The results showed that in the past 30 years, the grain crops’ yield and soil productivity contribution rates showed an overall increasing trend with time, and the annual growth rate of crop yield showed the change law of non-fertilizer area < conventional area, rice < wheat < corn. The yield of maize, wheat and rice in the non-fertilizer area increased from 2 370 kg·hm-2, 1 712 kg·hm-2 and 3 111 kg·hm-2 in 1988 to 4 852 kg·hm-2, 3 258 kg·hm-2 and 4 167 kg·hm-2 in 2019, and increased by 104.7%, 90.2% and 34.0%, respectively. The yield of corn, wheat and rice in the conventional area increased from 5 356 kg·hm-2, 3 296 kg·hm-2 and 5 970 kg·hm-2 in 1988 to 8 859 kg·hm-2, 6 515kg·hm-2 and 7 825kg·hm-2, respectively, with the increment of 65.4%, 97.6% and 31.0%, respectively. The contribution rate of soil productivity for the three major food crops in China from 2015 to 2019 was 52.7%, which was significantly increased by 7.3% compared with 45.4% in 1988-1994. Among them, the contribution rate in maize was 54.3%, which was 12.2% higher than that of 42.1% in 1988-1994. The contribution rate in rice was 53.3%, which was 6.7% higher than that of 46.6% in 1988-1994. The soil productivity contribution rate in wheat increased with the year as a whole, and was lower than that in corn and rice as a whole. The spatial distribution of soil productivity contribution rate for the three major grain crops is quite different. The Northeast region and Huang-Huai-Hai region are higher, which are 56.5% and 54.1% respectively, followed by the Southwest region and South region, which are 53.7% and 52.9% respectively. Gan-Xin region and Qinghai-Tibet region are the lowest, only 38.7% and 40.4% respectively. The random forest model was used to rank the soil factors affecting the basic soil productivity contribution rate in the three major grain crop systems. Soil available potassium content, soil available phosphorus content and soil pH were the most key factors affecting the basic soil productivity contribution rate of corn, wheat and rice, respectively.【Conclusion】 Over the past 30 years, the soil basic productivity for three major grain crops in China has been continuously improved, but there are great differences among regions and the overall level is still low, which is far lower than that of developed countries in Europe and United States. Soil available potassium, organic matter content and soil bulk density are the most key factors affecting maize soil basic productivity contribution rate, and soil available phosphorus, available potassium and organic matter content are the most key factors affecting wheat soil basic productivity contribution rate. Soil pH, soil available phosphorus and organic matter content are the most key factors affecting the contribution rate of rice soil basic productivity.


]]> <![CDATA[The Albino Mechanism of A New High Theanine Tea Cultivar ‘Fuhuang 1’]]> . 【Method】The experimental materials were ‘Fuan Dabaicha’ and ‘Fuhuang 1’. The combined analysis of ultramicroelectron microscopy, widely targeted metabolism, targeted metabolomics and transcriptomics is used to clarify the pigments, metabolism and transcriptome data related to the albino tea. 【Result】The results of ultrastructure showed that the chloroplast thylakoids of ‘Fuhuang 1’ was filamentous, with irregular arrangement of basal granule lamellae and many abnormal vesicles. Chlorophyll a and chlorophyll b content, chlorophyll a/b ratio, SGR gene expression and light-harvesting chlorophyll a/b protein (LHC) expression were significantly reduced in yellow leaves. Although the total content of carotenoids did not change significantly, the content of each component changed significantly. Zeaxanthin was the only component with significant increase, and the expression of its regulatory gene VDE was significantly up-regulated, and the content of other components decreased. Compared with ‘Fuan Dabaicha’, 680 differentially expressed genes (DEGs) and 57 significantly changed metabolites (SCMs) were identified in 'Fuhuang 1'. KEGG enrichment analysis showed that SCMs and DEGs were significantly enriched in pathways related to amino acid biosynthesis, glutathione metabolism and TCA cycle. In addition, pathways related to carbon and nitrogen metabolism were also activated. A total of 19 free amino acids were identified by targeted determination. The free amino acid content of ‘Fuhuang 1’ was 97.13 mg?g-1, which was significantly higher than that of ‘Fuan Dabaicha’. Theanine content was 66.90 mg?g-1, accounting for 68.89% of amino acids, while the content of arginine was 8.46 mg?g-1, which was 56.4 times as more as that of ‘Fuan Dabaicha’. The expression levels of GOGAT and GLU, which regulate amino acid synthesis, were up-regulated in ‘Fuhuang 1’ by 1.17 and 3.17 times higher than that in ‘Fuan Dabaicha’. 【Conclusion】The leaf color of ‘Fuhuang 1’ was mainly influenced by chlorophyll, carotenoids and flavonoids. The combined action of SGR and the four LHCs may also affected chloroplast biogenesis to regulate leaf color. The content of theanine in ‘Fuhuang 1’ was significantly higher than that in ‘Fuan Dabaicha’. The main reason was that the up-regulation of ubiquitination-related protein hydrolase activity and the enhanced protein degradation ability. The biosynthesis of chlorophyll and other nitrogen-containing molecules was reduced, the carbon skeleton in yellow leaves was lacking, amino and nitrogen resources were stored more effectively. The activation of nitrogen metabolism associated with amino acid synthesis led to the accumulation of glutamate, one of the precursors of theanine synthesis. Theanine accumulated significantly in yellow leaves.


]]> <![CDATA[Uptake and Bioaccumulation of 1-Nitropyrene in Soil-Scallion System]]> 】To elucidate the translocation and accumulation law of 1-nitropyrene from soil to plant, and thus to provide scientific data to support the research on dietary exposure risk to carcinogenic nitrated polycyclic aromatic hydrocarbons. 【Method】In this study, a soil-plant model was established through pot experiment, and blank, low-dose, high-dose polluted soils were used to plant scallion. Soil and plant (root and stem, leaf) samples were harvested after different growth period for analyzing 1-nitropyene levels, and the corresponding bio-concentration factors of each part were calculated by the bioaccumulation equation. 1-Nitropyrene levels and bioconcentration factors were compared with those of parent pyrene. The concentrations of 1-nitropyrene in plant and soil were determined by a modified QuEChERS method reported previously. After extraction and purification, a Fe/H+ derivatization process was followed up to convert the 1-nitropyrene to 1-aminopyrene to be quantitated by liquid chromatography coupled with fluorescence detection. The analytical method was validated using different part of scallion as matrix.【Result】The results showed that the analytical method demonstrated satisfied validation parameters, with the recovery ranged from 82.9% to 108.4% and RSDs no more than 13.2%. Concentration levels of 1-nitropyrene and pyrene in plant increased and then declined as time went by. Root and stem were the major part to uptake the 1-nitropyrene and pyrene via passive diffusion, while leaf only contributed 0.5-19.8% to the total uptake concentration of plant. Except for accumulating the pollutants from root via transpiration, the soil-air-leaf pathway contributed as well. The uptake and bioaccumulation behavior of pyrene was similar to that of 1-nitropyrene. 【Conclusion】1-Nitropyrene in soil could be translocated and accumulated to the edible part of plant, and stem is the major part to absorb 1-nitropyrene. Though the accumulation factors were similar, the toxicity of 1-nitropyrene was 104 more toxic than parent pyrene, the corresponding dietary exposure risk has been increased. Thus, more attentions are needed to pay to nitro-PAHs.


]]> <![CDATA[Research on Spatial Distribution of Soil Texture Loess Area Based on Machine Learning—Taking Southern Ningxia as an Example]]> Based on historical soil data, this paper studied the spatial variability of soil texture and its relationship with environmental factors in the loess region using machine learning.【Method】Classification and regression tree (CART), random forest (RF) and traditional statistical methods were used to explore the main environmental factors that affect the soil texture types and predict the spatial distribution of soil texture types in southern Ningxia, based on 428 soil profiles from the second soil survey in the 1980s, combined with topographic factors, soil types, and normalized vegetation Index. And the accuracy of the models were verified by the validating set of soil profiles and the soil samples in Haiyuan County, Ningxia.【Result】The accuracy rates of RF and CART on the soil texture type of the verification set of soil profiles were 62.36% and 55.29%, respectively. The area under the receiver operating characteristic (ROC) curve (Area Under ROC Curve, AUC) are 0.7515 and 0.6933, respectively. The accuracy rates on soil samples in Haiyuan County are 54.10% and 48.36% respectively, and the AUC are 0.6599 and 0.5981 respectively. Soil type (ST) is the most important predictor variable, followed by elevation (Ele), the higher elevation, the heavier and the soil texture. And finally wind exposition index (WEI) and slope (Slo). Results predicted by two methods show a spatial distribution trend that the soil texture is heavy in the southern area but light in the northern area of southern Ningxia.【Conclusion】The prediction accuracy of RF for soil texture type in southern Ningxia is higher than CART. Making full use of historical data, combined with field sampling, can meet the accuracy requirements of digital mapping. In the loess region, soil types and elevation are the environmental factors which have strong correlation with spatial variation of soil texture.


]]> <![CDATA[Effects of Melatonin Treatment on Quality of Stored ‘Shine Muscat’ Grapes Under Different Temperature]]> 】Cold storage is a very effective way to improve berry storage ability and extend shelf life. However, cold storage decreases fruit quality including sugars, acids and aroma. The paper was aimed to determine the effects of melatonin treatment on berry quality of ‘Shine Muscat’ under different storage temperature and to investigate the melatonin-induced changes of metabolites involved in quality formation. 【Method】The berries were treated via soaking with 5 and 50 μmol?L-1melatonin and stored at room temperature or 1℃. The berries at different days after storage were collected for quality analysis. Melatonin and aroma were determined using HPLC-MS and GC-MS, respectively. Capillary electrophoresis was used to detect soluble sugars and organic acids. Widely targeted metabolomics was employed to analyze the differentially accumulated metabolites. 【Results】Exogenous melatonin treatment significantly increased  melatonin content of the berries, and 50 μmol?L-1 melatonin was more effective than 5 μmol?L-1 melatonin. Additionally, melatonin treatment increased accumulation of melatonin more effectively at low temperature than it did at room temperature, e.g., the melatonin content of the berries treated with 50 μmol?L-1 melatonin at low temperature was 2.6 folds higher than that at room temperature. Water loss rate of berries decreased at low temperature.Melatonin treatment did not significantly affect water loss rate, skin and pulp firmness. At room temperature, 5 μmol?L-1 melatonin significantly increased content of glucose and fructose; however, 50 μmol?L-1 melatonin led to the contrary results. Cold storage produced negative effects on soluble sugars; in contrast, melatonin treatments increased content of soluble sugars at low temperature and the increments exceeded 19.2% at 40 days after cold storage. Cold storage increased titratable acidity and particularly malic acid compared to storage at room temperature. In contrast, melatonin significantly decreased titratable acidity and particularly malic acid of the berries with more than 53.5% decrement compared to the non-treated control under cold storage. Notably, berry aroma was largely reduced by cold storage, and melatonin and particularly 5 μM melatonin largely increased amount of total aroma and aroma components. The berries treated with 5 μmol?L-1 melatonin accumulated 2.12- and 1.6-fold higher aroma than the control berries at 30 and 40 days after cold storage, respectively. Additionally, melatonin increased the amount of characteristic aromas including (E)-2-hexenal, linalool and 2,4-Di-tert-butylphenol. Analysis of widely targeted metabolomics identified 232 differentially accumulated metabolites in the berries treated with 5 μmol?L-1 melatonin compared to the control berries under cold storage, which were primarily related to biosynthesis of amino acids, aminoacyl-tRNA biosynthesis, arginine biosynthesis, alanine, aspartate and glutamate metabolism and phenylalanine metabolism. 【Conclusion】Compared to storage at room temperature, cold storage decreased content of part of the soluble sugars and most of aroma components. The berries treated with melatonin accumulated significantly higher soluble sugars and aroma components and lower organic acids and thereby exhibited improved berry quality, and 5 μmol?L-1 melatonin was more effective. Additionally, the increased aroma amount might be dominantly associated with the changed amino acid metabolism in the berries treated with melatonin under cold storage.]]> <![CDATA[Widely targeted metabolomics analysis of the response to <i>Myzus persicae</i> feeding of resistant and susceptible <i>Prunus persica</i> #br#]]> 】The objective of this study is to reveal the underlying biochemical mechanisms related to the resistance and susceptibility of peach towards herbivory by Myzus persicae, and to identify the key secondary metabolites of peach responding to the M. persicae infection.【Method】Young leaves of resistant and susceptible peach trees were inoculated with M. persicae for 3 days and used for secondary metabolite extraction and UPLC-MS/MS analysis. Differentially altered metabolites (DAMs) were screened with |log2 fold change|≥1, q-value≤0.01 as threshold. The VIP value of the OPLS-DA model was used to perform differences between resistant and susceptible peach. By comparing the concentration difference between the resistant and susceptible varieties of peach after M. persicae feeding, the role of DAMs was explored.【Result】To illustrate the biochemical mechanisms of M. persicae resistance in peach, aphid-resistant/aphid-susceptible peach varieties infested with GPAs for 3 days. Widely targeted metabolomics analysis of the infested tissues identified 528 metabolites. Using principal component analysis (PCA), hierarchical cluster analysis (HCA) and venn diagram analysis, it was found that 7 differentially altered metabolites (DAMs) were identified from the susceptible varieties Zhong You 13 (CN13), and 2 of them were significantly decreased, 5 of them were significantly decreased. 7 DAMs were identified from the susceptible varieties Zhong Nong Jin Hui (ZNJH), and 3 of them were significantly decreased, 4 of them were significantly decreased. 33 DAMs were identified from the resistant varieties‘96-5-1’ (9651), and one of them was significantly decreased, 32 of them were significantly decreased. 55 DAMs were identified from the resistant varieties ZaoYouTao (ZYT), and 12 of them were significantly decreased, 43 of them were significantly decreased. The majority of the DAMs were identified from the two resistant varieties, and the overall magnitude of change was greater in the resistant varieties than in the susceptible varieties. Finally, 15 secondary metabolites (6 amino acid and derivatives, 5 phenolic acids, 3 nucleotides and derivatives, and 1 organic acid) were considered to be involved in M. persicae resistance of ‘Shou xing tao’.【Conclusion】The significantly up-regulated secondary metabolites obtained in M. persicae-resistant peach varieties were mainly involved in the response M. persicae feeding. The regulation of these secondary metabolites (amino acids and their derivatives, phenolic acids, nucleotides and their derivatives) is the important mechanism of defense reaction to M. persicae.


]]> <![CDATA[Quantitative Study on Effective Accumulated Temperature And Dry Matter And Nitrogen Accumulation of Summer Maize Under Different Nitrogen Supply Levels]]> 】This paper explores the dynamic prediction model and characteristic parameters of dry matter and nitrogen accumulation in summer maize with different nitrogen supply levels based on effective accumulated temperature, in order to provide a theoretical basis for using effective accumulated temperature to predict summer maize dry matter and nitrogen accumulation.【Method】This study is based on a two-year field experiment in Langfang, Hebei Province (2019-2020), using Zhengdan 958 as the test material, and using the normalization method to fit the dry matter and nitrogen accumulation of summer maize with different nitrogen supply levels through model screening. Based on the normalized Gompertz model of effective accumulated temperature after sowing, and using the growth rate curve and its characteristic parameters, the dry matter and nitrogen accumulation characteristics of summer maize were quantitatively analyzed.【Result】(1) Under the experimental conditions, when the amount of phosphorus and potassium fertilizer is appropriate, the maximum dry matter and nitrogen accumulation of summer maize continue to increase with the increase of nitrogen application rate.(2) The normalized Gompertz model of summer corn dry matter and nitrogen accumulation established with effective accumulated temperature as the independent variable has good biological significance.The coefficients of determination of the equation are 0.9962-0.9988 and 0.9887-0.9922, respectively. Using the second-year data for model verification, the correlation coefficients of the simulated and measured values were 0.9933-0.9959 and 0.9830-0.9923, and the standardized root mean square errors were 6.64%-16.86% and 7.31%-12.68%, respectively. The prediction effect was good. Level. (3) The growth rate of dry matter and nitrogen accumulation of summer maize at different nitrogen supply levels all showed a "single peak curve", and its change was closely related to the nitrogen supply level. The performance between treatments was: under the condition of moderate fertilization, the growth rate curve It has the characteristics of fast rising and falling, and the growth rate curve of weight loss treatment has the characteristics of slow rising and falling.(4) The effective accumulated temperature ranges of dry matter and nitrogen accumulation during the rapid increase period of summer corn after sowing are 709.35-1 722.54 °C·d and 482.50-1 507.61 °C·d, and the effective accumulated temperature required for the maximum rate shows that nitrogen accumulation (995.05°C·d) is less than Dry matter accumulation (1 215.94 ℃·d). Nitrogen supply level obviously affects the accumulation of dry matter and nitrogen in summer maize to enter the accumulation temperature required for the rapid increase period, the accumulated temperature required for the slow increase period, the accumulated temperature required for the maximum increase rate, the maximum increase rate, and the average increase rate during the rapid increase period; Compared with nitrogen fertilizer treatment, the effective accumulated temperature required for summer corn to enter each critical period was significantly reduced, and the growth rate during the critical period increased significantly.【Conclusion】The normalized Gompertz model can not only simulate and predict the dynamic changes of summer maize dry matter and nitrogen accumulation with effective accumulated temperature with different nitrogen supply levels, but also clarify the quantitative relationship between effective accumulated temperature and dry matter and nitrogen accumulation. The Gompertz model based on effective accumulated temperature can be used to predict crop growth and optimal fertilization period, and has strong application value.]]> <![CDATA[Association Analysis of the ADIPOQ Variation with Sheep Growth Traits]]> Objective】The aim of the study was to explore the effects of genetic variation of ADIPOQ on growth traits of sheep, and to find the molecular genetic markers related to growth traits in Ningxia high-quality mutton sheep breeding, so as to achieve the purpose of molecular assisted breeding. 【Method】Firstly, the mutation sites of ADIPOQ in Dupo sheep, Tan sheep and small-tailed Han sheep were obtained by Allegro Targeted Genotyping. At the same time, ear tissues of 383 different hybrid progenies of three breeds were collected. The SNPs were genotyped by Sequenom Mass ARRAY?SNP. Haploview was used to analysis linkage disequilibrium and construct haplotypes of the polymorphic loci. Association analysis between the SNPs in ADIPOQ with growth traits of newborn and 3-month-old sheep.【Result】A total of 7 SNPs were screened, and 7 SNPs showed polymorphism in the hybrid population. The dominant genotypes of SNP1-SNP7 were CC, GG, GG, CT, AG, GG and AA, and the dominant alleles were C, G, G, C, G, G and A. X2 test showed that all loci were in Hardy Weinberg equilibrium (except SNP7 site deviated from the equilibrium in all individuals). SNP1 (except F2), SNP4, SNP5 and SNP6 were moderately polymorphic (0.25 ≤ PIC < 0.50), SNP2 and SNP3 were moderately polymorphic (0.25 ≤ PIC < 0.50) in F2 and SNP7 were moderately polymorphic (0.25 ≤PIC < 0.50) in H1, and were low polymorphic (PIC < 0.25) in other populations. The results of linkage imbalance analysis showed that SNP2-SNP3 and SNP5-SNP6 formed two strong linkage, each of which constructed three haplotypes, and formed 4 and 6 genotypes respectively after combination, among which the dominant genotype was H1H1 and H4H6. 13 genotypes were produced after the haplotypes formed by SNP2-SNP3 and SNP5-SNP6 were recombined, and the dominant genotype was H1H1H4H6. Single SNP correlation analysis revealed that: SNP1 site in F1 population, the primary chest of GG genotype was significantly higher than that of CG genotype(P<0.05), and in H2 population, the primary body length of CC genotype was significantly higher than that of GG genotype(P<0.05). SNP2 site in H1 population, the primary body height of CC genotype was significantly lower than that of CG and GG genotypes (P < 0.05). SNP3 site in F1 population, the three months body weight of AG genotype was significantly higher than that of GG genotype, and in H1 population, the primary body height of AA genotype was significantly lower than AG and GG genotypes (P<0.05). SNP4 site in F1 population, the three months weight of CC genotype was significantly higher than that of CT and TT genotypes(P<0.05), in F2 population, the primary weight and primary chest of CT genotype were significantly higher than that of TT genotype(P<0.05). and that of TT genotype was significantly lower than that of CC and CT genotype(P<0.05) in H1 population, and in H2 population, the primary body height and primary body length of TT genotype were significantly higher than that of CT genotype(P<0.05). SNP5 site in F2 population, AA genotype had significantly higher primary body height and primary body length than GG genotype(P<0.05). There were significant differences in primary weight, body height, body length, three months body height and chest among different genotypes of SNP6(P<0.05). SNP7 site in H2 population, AA genotype had significantly higher primary body length than GA genotype(P<0.05).When combined with all groups, we found that , the primary weight and body length of CG genotype at SNP2 were significantly higher than GG genotype(P<0.05), the primary weight of TT genotype at SNP4 was significantly lower than CC and CT genotypes(P<0.05), the primary weight of AA genotype at SNP6 was significantly higher than GG and GA genotype(P<0.05), and the primary chest was significantly higher than GG genotypes(P<0.05). There was no significant difference in growth traits among the other five genotypes(P>0.05). The results of haplotype association analysis showed that the primary weight and primary body length of H2H3 genotype were significantly higher than those of other genotypes(P<0.05), while the primary weight of H5H5 genotype was significantly higher than that of H5H6 and H6H6(P<0.05), the primary body height was significantly higher than that of H5H6(P<0.05), the primary chest was significantly higher than that of H6H6(P<0.05), and the three months weight of H4H4 genotype was significantly higher than that of H5H5 genotype(P<0.05), the body weight and body length at three months were significantly higher than those of H4H6 genotype(P<0.05), and the chest of three months was significantly higher than that of H4H5,H5H6 and H5H5 genotype(P<0.05). After SNP2-SNP3 and SNP5-SNP6 haplotypes were recombined, the primary weight, body height, body length and chest of H2H3H4H4 genotype were the highest, which were different from other genotypes. The body length of H1H2H4H4 and H2H2H4H4 genotypes(P<0.05).【Conclusion】The results showed that the different SNPs and combined genotypes in ADIPOQ had effect on sheep different growth traits, the seven SNPs in this study can be used as potential molecular markers for growth traits in Ningxia high quality mutton sheep breeding.


]]> <![CDATA[Relationship Between Biofilm Formation and Molecular Typing of Staphylococcus Aureus from Animal Origin]]> staphylococcus aureus in the biofilm producing strains and to explore the correlation between biofilm forming ability and molecular typing, so as to provide theoretical basis for the treatment of Staphylococcus aureus infection. 【Method】 The biofilm producing ability of all strains of Staphylococcus aureus was determined by crystal violet semi-quantitative method.The minimum inhibitory concentrations of 22 common antibiotics were determined by the membrane producing strains. Molecular typing was conducted by three common typing methods of Staphylococcus aureus (spa typing, MLST typing and PFGE typing), and the correlation between membrane production capacity and molecular typing was analyzed. Finally, whole genome sequencing technology was used to analyze the antibiotics resistance gene and virulence genes in the biofilm producing strains. 【Result】 The semi-quantitative results of crystalline violet showed that a total of 23 strains (23.47%) of 98 S. aureus strains were able to produce biofilm, including 22 strains (25.29%, 22/87) from cow milk source, 14 strains (60.87%, 14/22) from Zhejiang dairy farms, 8 strains (39.13%, 8/22) from Fujian dairy farms, and 1 strain from pig source ( 9.10%, 1/11) from Guangdong slaughterhouse, indicating that the film-producing potential of Staphylococcus aureus from cow's milk source was higher than that of pig source of which 22 strains (95.65%) were from cow's milk source and 1 strain (4.35%) was from pig source; the film-producing ability was classified into strong, medium and weak, and among the 23 film-producing strains, 2 strains (8.70%, 2/23) were strong film-producing strains and 9 strains (39.13%, 9/23) were medium film-producing strains. (39.13%, 9/23), 12 (52.17%, 12/23) of weak film-producing strains were strong (2/23=2.70%), medium (9/23=39.13%), and weak (12/23=52.17%), respectively; the results of drug sensitivity test showed that the film-producing strains of cow milk origin were sensitive to all antibacterial drugs tested, while the film-producing strains of pig origin were sensitive to all antibacterial drugs including penicillin, clindamycin, and tilmicin. The results of the drug sensitivity test showed that the bovine milk-derived membrane-producing strains were sensitive to all the tested antibacterial drugs, while the pig-derived membrane-producing strains showed resistance to 13 antibacterial drugs, including penicillin, amoxicillin, ceftiofur, cefoxitin, enrofloxacin, ciprofloxacin, clindamycin, doxycycline, erythromycin, flupenthixol, cotrimoxazole, tiamulin, and tilmicosin. The spa typing results showed that 98 strains of S. aureus obtained 8 spa types, and 23 strains of film-producing S. aureus accounted for 3 of them: 1 strain t2922 from porcine origin in Guangdong, 14 strains t2119 from Zhejiang cow milk source, and 8 strains t189 from Fujian cow milk source; MLST typing results showed that spa typing and MLST typing results showed that all strains were classified into 8 spa types and 9 ST types, and 98 strains were classified into 9 ST types, of which 6 ST types did not have the ability to produce biofilm, namely ST398, ST522, ST705, ST ST1651, ST479 and ST151, and only 3 strains of ST type had biofilm production ability, namely ST9, ST7 and ST188; we found that the molecular types of strong film-producing strains were mainly ST7-t2119, medium film-producing strains were mainly ST7-t2119 and ST188-t189, and weak film-producing strains were ST9-t2922, ST7-t2119 and ST188-t189. The strains with membrane producing ability were mainly ST7-t2119, medium membrane producing strains were mainly ST7-t2119 and ST188-t189, weak membrane producing strains were ST9-t2922, ST7-t2119 and ST188-t189. ST7-t2119 and ST188-t189, the ST type of weak film-producing strains can be well distinguished from the medium and strong film-producing strains, and only the specific ST type of S. aureus has the ability to produce biofilm. 23 film-producing strains PFGE typing all successful PFGE typing results show that the results show that each strain of film-producing bacteria in Guangdong, Fujian and Zhejiang provinces are divided into a total of three The results show that there are geographical distribution characteristics of PFGE types, and isolates from the same region may have clonal transmission, and strains in the province are clonal to each other, but there are significant differences in biofilm production ability between clones; whole genome sequencing results show that the drug resistance genes and virulence genes in the film-producing strains are diverse according to the molecular type. 【Conclusion】 Staphylococcus aureus from different sources have different potential to produce biofilm and all carry different film-producing genes; the film-producing potential of S. aureus from bovine milk source is much higher than that of porcine source and all carry different film-producing genes; whether strains can produce film or not may be strongly correlated with ST type, and specific ST types such as ST9, ST7 and ST188 are more likely to produce biofilm; however, at the same time, strains with the same molecular type have different abilities to produce biofilm.]]> <![CDATA[Transcription Factor TEAD4 Regulates Early Embryonic Development in Pigs]]> 】TEA domain transcription factor 4 (TEAD4) is known to be a member of the TEAD family of transcription factors and plays a key role in determining the characteristics of the preimplantation embryo in rodents. In mouse embryos, it was found to be involved in regulating the genealogical differentiation of trophectoderm cells in preimplantation embryos by promoting Cdx2 expression. The absence of the TEAD4 gene in mouse embryos can lead to failure of mouse blastocyst formation. However, the role of TEAD4 in early porcine embryonic development is still unclear. Here we aim to preliminarily elucidate the effect of TEAD4 on early porcine embryonic development in order to lay the theoretical foundation for further exploring the molecular mechanisms of transcription factors on early porcine embryonic development.【Method】In this study, bioinformatics analysis of the porcine TEAD4 gene was performed using web-based tools, including analysis of the porcine TEAD4 gene sequence, comparison of homology between pigs and humans and mice, and comparison of the evolutionary relationship of TEAD4 between different species. The role of TEAD4 in early embryonic development in pigs was then tested. The mRNA expression level of TEAD4 gene in porcine oocytes and early embryos was firstly detected by fluorescence quantitative PCR, and then by designing siRNA targeting TEAD4 and injecting it into mature oocytes by microinjection technique to reduce the level of endogenous TEAD4 gene in the oocyte cytoplasm, and to determine that TEAD4 siRNA acts only on TEAD4 gene, with a view to determining the role of TEAD4 gene in early porcine embryonic development.【Results】.Sequence analysis showed that the porcine TEAD4 gene contains 11 exons, localized on chromosome 5, spanning 37.188 kb, 1473 bp in full mRNA length, 1305 bp in full coding region, and encoding 434 amino acids. Homology analysis with human and mouse revealed that TEAD4 is highly conserved in different species and has the closest affinity on pig and cow. The results of fluorescence quantitative PCR showed that TEAD4 mRNA was expressed in both porcine oocytes and early embryos, and when compared with GV-stage oocytes, the expression was lowest in MII-stage oocytes and remained low until the 4-cell stage, but reached the highest expression in the 8-cell stage, and then gradually decreased in the morula and blastocyst stages. Microinjection of siRNA targeting TEAD4 revealed that TEAD4 siRNA only acted on the endogenous TEAD4 gene in oocytes, but not on TEAD1 and TEAD3, and compared with the control and negative control siRNA groups, injection of TEAD4 siRNA significantly reduced TEAD4 mRNA expression at the 8-cell and morula embryo periods. When TEAD4 gene expression was knocked down, observation of the developmental efficiency of porcine orphan activation and in vitro fertilization embryos showed that the developmental efficiency of TEAD4 siRNA knockdown group from 8-cell to blastocyst stage was significantly reduced compared to the control and negative control siRNA groups.【Conclusion】The results of this study indicate that the TEAD4 gene is highly conserved across species, with the closest affinity on pigs and bovine, and that TEDA4 may be involved in regulating the development of early porcine embryos.


]]> <![CDATA[Humic Acid-urea Complex Combined with Urea on the Characteristics of Ammonia Volatilization of Different Fertilized Soils]]> 】 Application of humic acid enhanced urea (HAU) can effectively reduce ammonia volatilization. The humic acid in HAU, named UHA, plays a great role in this process. However, due to the reaction between humic acid and urea, the effect of UHA on soil ammonia volatilization may be different from that of conventional humic acid (HA). Relevant research will help to further reveal the mechanism of HAU reducing ammonia volatilization from soil. 【Method】In this study, UHA was extracted by absolute ethanol from HAU. The effects of HA or UHA combined with urea on ammonia volatilization of long-term unfertilized soil or fertilized soil were studied. The dosage of HA or UHA was 0.5% and 5% of the amount of urea, code named 0.5HA+U, 5HA+U, 0.5UHA+U, and 5UHA+U, respectively. Treatment with urea (U) and without humic acid and urea (CK) were conducted at the same time. Soil ammonia fluxes and volatilization, soil urea-N, nitrate, and ammonium content, and soil urease activity were measured simultaneously.【Result】(1) The ammonia volatilization for long-term fertilized soil was higher than that for long-term unfertilized soil, which might be related to low soil pH and prolonged urea residue due to long-term fertilization. (2) Both HA and UHA combined with urea could effectively reduce soil ammonia volatilization, compared with U treatment, but the extent of the reduction depended on whether the soil was fertilized for a long time and the amounts of HA or UHA: urea combined with HA could significantly reduce soil ammonia volatilization for long-term unfertilized soil (P<0.05), and the ammonia volatilization of 0.5HA+U and 5HA+U was 4.39% and 22.88% lower than U treatment, respectively. While the application of HA did not significantly affect ammonia volatilization for long-term fertilized soil. 0.5UHA+U could significantly reduce soil ammonia volatilization (P<0.05) for long-term unfertilized and fertilized soil by 26.46% and 12.91%, respectively. (3) Combined application of HA could effectively inhibit urease activity, and UHA could promote the nitrification process, thereby reduced soil ammonia volatilization. 【Conclusion】In summary, compared with HA, UHA showed better performance on inhibiting ammonia volatilization, and the effect was independent of whether the soil was fertilized for a long time.


]]> <![CDATA[The spatial characteristics of <span>soil organic carbon</span> <span>sequestration</span> and N<sub>2</sub>O emission with manure <span>fertilization scenarios </span>from dry land in North China Plain]]> Objective】Greenhouse gas (GHGs) emissions caused by agricultural activities have become one of the most important factors causing global warming. The North China Plain is a main food production region in China, optimizing the fertilization strategy in the North China Plain is of great significance to reduce GHGs emissions and mitigate climate change.【Method】Based on long-term experiment, this study used the validated process-based model-SPACSYS, combined with regional database and ArcGIS, clarified the spatial characteristics of average annual soil organic carbon sequestration rate (?SOC), average annual N2O emission and average annual net global warming potential (NGWP) under three long-term fertilization scenarios (equal nitrogen fertilization), namely, chemical fertilizers only (NPK), 50% of chemical fertilizers combined with 50% of manure (NPKM(5:5)) and 30% of chemical fertilizers combined with 70% of manure (NPKM (3:7) ) from dry land in the North China Plain from 2010 to 2050.【Result】The average annual soil organic carbon sequestration rate from dry land in the North China Plain was higher in the east and lower in the west, and the higher regions mainly included Jiangsu and Shandong provinces. Correlation analysis showed that there was a significant negative correlation between ?SOC and initial soil organic carbon content. Stepwise linear regression analysis further indicated that initial soil organic carbon content, mean annual temperature and soil pH were three important factors affecting ?SOC, which accounted for 24% of the variation of ?SOC. The average annual N2O emission was higher in the central part of the North China Plain, lower in the north and south, and the higher regions included parts of Shandong Province and Jiangsu Province. Correlation analysis showed that there was a significant positive correlation between average annual N2O emission and initial soil organic carbon content. In general, compared with NPK, NPKM(5:5) and NPKM(3:7) both increased ?SOC and decreased soil N2O emission from dry land in the North China Plain, of which ?SOC（233 and 236 kg C·hm-2·a-1)）increased by 79% and 82%, respectively, the average annual N2O emission（15.8 and 14.4 kg N·hm-2·a-1)）decreased by 21% and 28%, respectively. As a result, NGWP（6.6 and 5.9 t CO2-equivalent·hm-2·a-1)）decreased by 26% and 34%, respectively.【Conclusion】Compared with the application of chemical fertilizers, long-term application of chemical fertilizers combined with manure is beneficial to soil carbon sequestration, soil N2O emission reduction and mitigation of glowing warming from dry land in the North China Plain over the long-term.


]]> <![CDATA[Soil Available Sulfur Content in Jilin Province and The Correlation with Soil Organic Matter and Soil Total Nitrogen]]> 】 To clarify the status of effective sulfur content of dryland soils in Jilin Province and its distribution differences, to provide a basis for reasonable sulfur application to regional crops.【Method】232 surface (0-20 cm) soil samples were collected from 8 major soil types in different ecological zones of Jilin Province, and the spatial distribution characteristics of effective sulfur content were analyzed by geostatistical methods to compare the differences in effective sulfur content of different types of soils and to establish the correlation between effective sulfur and organic matter and total nitrogen in soils.【Result】 The distribution of effective sulfur content in dryland soils of Jilin Province ranged from 5.8 to 40.7 mg·kg-1, with a mean value of 18.06 mg·kg-1. The proportions of sulfur deficiency and potential sulfur deficiency in all samples were 27.2% and 20.7%, respectively. Spatial distribution showed that the overall trend of effective soil sulfur content gradually decreased from east to west, and the corresponding incidence of sulfur deficiency gradually increased from east to west. The mean values of soil effective sulfur content (incidence of sulfur deficiency or potential sulfur deficiency) in the three major ecological zones of east, central and west were 22.3 mg·kg-1 (24.2%), 18.1 mg·kg-1 (40%) and 14.3 mg·kg-1 (75.6%), respectively. The mean values of effective sulfur content of albic soil and dark brown loam, which were mainly distributed in Eastern humid mountainous area, were 22.1 and 22.0 mg·kg-1, respectively, and 15.2% and 28.3% of the samples were sulfur deficient or potentially sulfur deficient, respectively; the mean values of effective sulfur content of black soil, alluvial soil and meadow soil in the central semi-humid plain area were 18.8 mg·kg-1, 17.1 mg·kg-1 and 16.2 mg·kg-1. The mean values of effective sulfur content of chernozem, aeolian sandy soil and saline-alkali soil in the western semi-arid plain area were 11.9 mg·kg-1, 14.0 mg·kg-1 and 13.9 mg·kg-1, respectively, with higher risk of sulfur deficiency or potential sulfur deficiency, accounting for 73.6%, 73.3% and 75.5% of the samples, respectively. 73.3% and 75.5%, respectively. The regression analysis results showed that the effective sulfur in dryland soils of Jilin Province was significantly logarithmically correlated with soil total nitrogen and soil organic matter, and the effective sulfur content of soil increased with the increase of soil organic matter and soil total nitrogen content. 【Conclusion】 The effective sulfur content of dryland soils in Jilin Province varies significantly among regions and soil types, and deficiency is more common, especially in aeolian sandy soil, saline-alkali soil and chernozem in the central and western regions, where the risk of sulfur deficiency is higher, and sulfur supplementation should be emphasized in soil fertilization and crop management.


]]> <![CDATA[Effect on Control Efficacy of <i>Pseudomonas</i> <i>alcaliphila </i>strain Ej2 against Rice Blast and Endogenous Hormones in Plant]]> 】This study aimed to definitude the antagonist activity of Pseudomonas alcaliphila strain Ej2 against various phytopathogens concluding Fusarium spp. in vitro, focusing on control efficacy of P. alcaliphila Ej2 against rice blast and influences of endogenous hormones in plant. The research can provide new biocontrol resources for the research and development of fungicides against rice blast.【Method】P. alcaliphila strain Ej2 was isolated from endophytic bacteria into rice leaf tissue. Antagonistic action of strain Ej2 against other five pathogenic fungi, such as Fusarium spp., Colletotrichum gloeospoioides, Alternaria alternate which can cause apple spot fallen leaf disease and strawberry black spot, et al., was determined by dual culture assay. In addition, antagonistic activity of volatile substance produced by P. alcaliphila strain Ej2 against Magnaporthe oryzae and promoting efficacy of fermentation broth increasing the germinating rate of rice seeds were tested in the experiment. The control efficacy of strain Ej2 was determined for the control of rice leaf blast under greenhouse condition by pot-culture method. The pot experiments were used to verify the promoting and control efficacy of strain Ej2 against rice leaf blast and neck blast. Targeted metabonomics based on MRM method was detected effect on endogenous hormones in plant such as stress hormone and cytokinin after fermentation broth sprayed for three times.【Result】The strain and volatile substance suppressed the colony growth rate of M. oryzae P131 significantly. The control efficacy against rice blast under greenhouse condition was 78.26% and it had no significant difference with 75% tricyclazole wettable powder. What’s more, the control efficacy against rice leaf blast and neck blast in field were 75.07%-83.67% and 62.79%-75.09%, respectively. It had significant difference between the control efficacy of strain Ej2 and 20% fenoxanil suspending agent against rice leaf blast. But it had no significant difference between the control efficacy of strain Ej2 and 20% fenoxanil suspending agent against rice neck blast. P. alcaliphila Ej2 showed strong antagonist activity against other five pathogenic fungi, such as F. oxysporum f. sp. niveum, F. solani, F. moniliforme, C. gloeospoioides, Alternaria alternate, et al. The fermentation broth of P. alcaliphila Ej2 significantly increased the germinating rate of rice seeds, plant height, panicle weight and thousand kernel weight. After spraying three times, the level of the stress hormone in plant such as ethylene (ETH) and abscisic acid (ABA) were significantly increased, but the level of cytokinin such as zeatin riboside (czR), trans-zeatin riboside (tZ) and N6-isopentenyladenine riboside (iPR) were evidently decreased. In addition, the level of several endogenous hormones in plant including IAA, JA, cis-OPDA, JA-LIE, cZ, tZ, iP and SA had no evident change.【Conclusion】P. alkalophilis strain Ej2 possesses the application value to control disease, promote crop growth and enhance stress resistance of rice plant, and it is considered to be a biological control nicroorganism against rice blast and other fungi diseases.

]]> <![CDATA[Antibody Preparation and Subcellular Localization of LmKnk3-5′ in Locusta migratoria]]> 】LmKnickkopf3-5′ (LmKnk3-5′) is an important cuticular protein involved in the development of Locusta migratoria. The purpose of this paper is to get the anti-LmKnk3-5′ polyclonal antibody and confirm the localization of LmKnk3-5′ in L. migratoria. The results will be beneficial to the biological functional analysis of LmKnk3-5′ from protein level, meanwhile, it can lay the foundation for further study of the interaction of cuticular proteins in cuticle formation in L. migratoria.【Method】Three specific antigen sequences (R1, R2 and R3) of LmKnk3-5′ were chosen after amino acid sequences alignment of Knickkopf (Knk) family genes in L. migratoria, including LmKnk, LmKnk2, LmKnk3-FL and LmKnk3-5′. The target antigen sequences were amplified by PCR used primers with BamH I, Hind III restriction sites and full-length cDNA sequences of LmKnk3-5′ as template. The antigen sequences and pET-32a vector were all digested by BamH I, Hind III and ligated to each other by T4 ligase enzyme to make recombinant plasmids, then the recombinant plasmids were transformed into BL21 (DE3) competent cells. The cells were incubated with 0.5 mmol·L-1 IPTG at 16℃ for 20 h to produce the recombinant fusion protein, SDS-PAGE was used to analysis the expression of target proteins. After that, E. coli cells that can express target proteins in dissolved state were expanded cultured for protein extraction. Ni-NTA agarose were used for target proteins purification and BCA method were used to determine the protein concentration. The LmKnk3-5′ polyclonal antibodies were obtained after immunizing BALB/c mouse four times. ELISA and western blot were used to analysis the antibody titer and specificity respectively. Finally, the paraffin sections were prepared used the integument of 8-day-old fifth-instar nymphs after dsLmKnk3-5′ and dsGFP injection, immunofluorescence were conducted to confirm the subcellular localization of LmKnk3-5′ in L. migratoria.【Result】R1, R2 and R3 were selected as specific antigen regions through amino acid sequences alignment. R1, R2, R3 consist of 208, 147 and 131 aa. and the predicted molecular weight of them are 24.0, 17.0 and 14.8 kD, respectively. Three recombinant plasmids (pET-32a-R1, pET-32a-R2, pET-32a-R3) were obtained successfully after enzyme digestion and ligation. SDS-PAGE analysis showed that only the cells consist of pET-32a-R2 plasmids can express target proteins in dissolved state after induced by IPTG. R2 recombinant fusion protein were purified and used to obtain anti-LmKnk3-5′ polyclonal antibody successfully after immunizing mice. ELISA analysis indicated that the titer of LmKnk3-5’ antibody was up to 1﹕512 000. The results of western blot demonstrated that after dsLmKnk3-5′ injection, the expression of LmKnk3-5′ was significantly decreased in comparison of the dsGFP injection group. The results of immunofluorescence showed that LmKnk3-5′ was located in the epidermal cells and new cuticle, especially the apical site of exocuticle in L. migratoria. 【Conclusion】Anti-LmKnk3-5′ polyclonal antibody were obtained successfully, it has high titer and specificity. LmKnk3-5′ was mainly located in the apical site of exocuticle newly synthesized in L. migratoria. The results will provide protein level evidence for the functional research of LmKnk3-5′ in the cuticle formation of L. migratoria.


]]> <![CDATA[Overexpression of OsPR1A Enhanced Xa21-Mediated Resistance to Rice Bacterial Blight]]> 】Previous studies revealed that the expression of pathogenesis-related protein OsPR1A was regulated by the upstream resistance gene Xa21. The rapid induction of OsPR1A protein at early stage after inoculation was crucial in Xa21-mediated rice bacterial blight resistance. The expression of OsPR1A was induced by Xanthomonas oryzae pv. oryzae (Xoo). OsPR1A was well known as a marker gene to demonstrate the reaction between rice and pathogen, however, no direct evidence was obtained for the biological function of OsPR1A. In this paper, transgenic plants overexpression OsPR1A were obtained and the phenotype and agronomic traits were investigated. The relationship between OsPR1A expression and resistance were surveyed to further explore the function of OsPR1A in the process of rice resistance to bacterial blight.【Method】The construct of OsPR1a-OX was transferred to rice recipient 4021 via Agrobacterium-mediated protocol. Positive homozygous transgenic lines were identified by PCR and western blot (WB) respectively. At the mature stage, the phenotype and agronomic traits of OsPR1A overexpression rice plants were investigated, including plant height, spike length, tiller number, seed setting rate and grain size. Rice seedlings of TP309, 4021 and OsPR1A overexpression plants grown for two weeks were inoculated with Xoo at 31℃. The length of lesions was measured at 0, 2, 4, 6, 8, 10, and 12 days post-inoculation (dpi) respectively. At 0, 4 and 6 dpi, the rice leaves of TP309, 4021 and OsPR1A overexpression plants were collected to extract total protein, and the expression profiling of OsPR1A were surveyed by WB.【Result】The OsPR1a-OX transformation vector was constructed and transformed into recipient 4021. Two homozygous OsPR1A overexpression lines (#704 and #709) were identified. At the mature stage, the phenotype and agronomic traits of the OsPR1A overexpression plants were investigated. Compared with the control 4021, #704 and #709 lines showed lower plant height, shorter spike length, fewer tiller number, lower seed-setting rate. The grain size in transgenic rice plants were larger, which might be related to the lower seed-setting rate. At 31℃, the lesion length of OsPR1A overexpression plants was significantly shorter than that of the control 4021 (P<0.05). At 0, 4, and 6 dpi, the abundance of OsPR1A expression of overexpression plants was higher than that of 4021 and TP309, and the high level of OsPR1A protein might contribute to the resistance of Xoo.【Conclusion】OsPR1A overexpression transgenic plants were obtained by the Agrobacterium-mediated method. Overexpression of OsPR1A affected the normal development of rice plants and also enhanced the resistance to bacterial blight mediated by Xa21.]]> <![CDATA[Spatial-Temporal Variability of Soil Nutrients and Assessment of Soil Fertility in Erhai Lake Basin]]> 】By studying the spatial-temporal variation characteristics of tobacco-planting soil nutrients in Erhai Lake Basin (ELB), the objective of grading evaluation and spatial visualization of tobacco-planting soil fertility in this region was achieved, so as to provide scientific basis for the nutrient management, balanced fertilization, and the control of agricultural non-point source pollution of tobacco-planting areas in ELB.【Method】Based on the 964 tobacco-planting soil samples in ELB collected in 2011-2013, 2018 and 2020, this study explored the spatial-temporal variability of nutrients and regional distribution patterns using Geostatistics, Geographic Information Systems (GIS) technology, and Fuzzy integrated fertility index method to quantify the soil fertility in tobacco-planting areas. 【Result】The average values of soil pH, soil organic matter (SOM), total nitrogen (TN), available phosphorus (AP) and available potassium (AK) of tobacco-planting soil in the ELB were 7.34, 59.55 g kg-1, 3.49 g kg-1, 54.43 mg kg-1, and 191.99 mg kg-1, all of which belonging to moderate variation. Tobacco-planting soil was rich in SOM, TN, available AP and AK, and the proportions of areas within the upper-middle level accounted for 85.2%, 93.8%, 94.2% and 78.8% , respectively, showing obvious variation at regional scale. The area of tobacco-planting soil fertility were graded to five levels (from high to low: I to V), which accounted for 8.0%, 21.60%, 38.11%, 28.9% and 3.49%, respectively. 【Conclusion】The pH of tobacco-planting soil was relatively alkaline in ELB, which was higher in the northern than in the southern; the highest concentrations of SOM and TN occurred in the northern and the western region; the areas with high AP concentration were distributed in patches in the upper and middle region of the Sanjiang River, Eastern eastern and western region; the areas with high AK concentration were distributed in flakes in the northern and eastern of Erhai Lake. Collectively, the fertility of the tobacco-growing soil in ELB was in high level, and the high-quality soil areas above Grade III were mainly distributed in the northern and eastern region.


]]> <![CDATA[Influences of Mulching Period and Nitrogen Addition Levels on Maize Yield and Water and Nitrogen Use Efficiencies in Dryland of the Loess Plateau of Eastern Gansu Province]]> 】To optimize the agricultural practice in supporting high production and high efficiency of spring maize cultivation in dryland region of eastern Gansu province, the effects of film mulching period and nitrogen addition level on maize physiology, yield, and water and nitrogen (N) use efficiencies were investigated in this study, using a compact maize variety (xianyu 335) with high stress resistance as tested crop.【Methods】A two-factorial experiment with split-plot design was established from 2012 to 2019, which consisted of two treatments of mulching period (spring and autumn mulching) and seven levels of N addition (0, 75, 150, 225, 300, 375, 450 kg N·hm-2), and the physiological characteristics, yield variables, and water and N use efficiencies of maize plants under different treatments were annually measured.【Results】Film mulching and moderate levels of N addition increased the photosynthetic rate and the relative content of leaf chlorophyll (SPAD value), extended the green duration of leaves, efficiently balanced the source-sink relationship, and improved the grain number per spike and 100-grain weight. The yield, grain number per spike and 100-grain weight of maize were significantly affected by N application rate, annual rainfall pattern and their interactions, and all these variables showed similar trends of inverted U-shaped curves with the increasing of N addition levels. Maize yields under treatments with N addition of 150~450 kg N·hm-2 were significantly higher than that of 75 kg N·hm-2, with a peak (15142.5kg·hm-2) occurring in the treatment with N addition of 300 kg N·hm-2. The yields did not differ significantly between treatments with N addition of 225 kg and 300 kg N·hm-2, whereas maize yield would not increase or even decline when N inputs were beyond the level of 300 kg N·hm-2. Maize yield was highly dependent on the annual rainfall pattern and the amounts of precipitation in key growth periods, of which the rainfall amount from July to September, especially in early July (tasseling-silking stage of maize), as well as the type of drought year were especially important in determining maize yield. Furthermore, film mulching period, experimental year, nitrogen application rate and the interaction between nitrogen application rate and rainfall annual pattern also significantly affected the water use efficiency (WUE). The WUE under autumn film mulching was 8.6% higher than that under spring film mulching. The N partial factor productivity and N use efficiency under treatment of 225 kg N·hm-2 were increased by 28.6% and 20.1% than that under 300 kg N·hm-2, respectively. Moreover, the average N use efficiency was increased from 34.8% under treatment of 300 kg N·hm-2 to 35.8% under 225 kg N·hm-2. In other words, 225 kg N·hm-2 can realize the simultaneous increases in maize yield and N use efficiency.【Conclusion】These results suggest that film mulching and nitrogen addition of 150~225kg·hm-2 could be used as efficient models for maize cultivation, especially with autumn film mulching in dry years. Farmers should choose the appropriate mulching practice and N addition levels according to the weather forecast in annual rainfall types.

]]> <![CDATA[Canopy Population Quality of Mechanical Transplanting Hybrid Indica Rice with “Reducing Hills and Stabilizing Basic-seedlings” in Low-light Region of Southwest China]]> 4/hm2 and 63×104/hm2) were conducted to study the effects of different field collocation patterns (conventional field collocation (CFC) and RHSB) on the canopy architecture, photosynthetic characteristics, and microclimate environment (e.g. canopy temperature, humidity, and light transmittances) of mechanical transplanting hybrid rice population in 2016 and 2017, respectively. 【Result】(1) Compared to CFC, RHSB with a greater specific leaf weight of the upper three leaves (Fsecond leaf=23.67** and Fthird leaf=16.91** in 2017), could maintain a similar green leaf area per stem and grain/leaf ratio at heading stage. Compared to CFC, RHSB also leaded to the 23.84%, 23.53%, and 13.79% significant increases in photosynthetic rate, stomatal conductance, and transpiration rate of flag leaf at the heading stage, respectively. (2) RHSB markedly decreased the canopy convergent index, but increased the canopy amplitude, which increased in light transmittance and ventilation of canopy. RHSB increased the angle of primary tillerings of Fyou 498 at the booting stage and heading stage in 2016, but decreased the angle of primary tillerings of Yixiangyou 2115 in both years..  (3) Correlation analysis indicated that daily average temperature and diurnal variations of temperature and humidity at booting stage were significantly or extremely significantly positively correlated with the specific leaf weight of the flage leaf and the 2nd leaf at the heading stage, but significantly negatively correlated with plant convergent index at the heading stage. Furthermore, the daily average temperature and diurnal variations of humidity at the booting stage was significantly positively correlated with canopy amplitude at the heading stage. Daily average temperature and diurnal variations of temperature at the heading stage were significantly or extremely significantly negatively correlated with the angle of primary tillering at the tilling stage, jointing stage, and 20 d after heading stage. However, the inverse relation was observed by daily average relative humidity. RHSB could optimize the  canopy architecture of rice, which contributed to the increase in canopy temperature and diurnal the variations of temperature at booting and heading stage，and increase diurnal the variations of humidity at booting, heading and 20 d after heading stage, but decrease in the relative humidity.【Conclusion】As one of the main technology that improved the mechanization level of rice production in the low-light region of Southwest China, RHSB optimized the population canopy structure and light distribution of mechanical transplanting hybrid rice, which resulted in the increase in the temperature and humidity difference between day and night within the population and reduced the relative humidity. This contributed to the improvement in the population quality and photosynthetic rate, and contributed to the increase in grain yield of rice.

]]> <![CDATA[Chemical Constituents of Yongchun Foshou Oolong tea Based on Metabolomics]]> Objective】 Oolong teas made with different tea cultivars have a great difference in flavor and chemical components. In this study, non-targeted metabolomics, absolute quantitative analysis, and multivariate statistics analysis were used to investigate the chemical differences among Yongchun Foshou (YCFS), Tieguanyin (TGY) and Shuixian (SX) oolong tea and to screen characteristic chemical components of YCFS oolong tea, as well as to study the influence of tea cultivar on chemical components and sensory quality of oolong tea. 【Method】 Three cultivars were included and were manufactured into fresh-scent, strong-scent and aged-scent oolong teas, in which Camellia sinensis cv. Foshou was used as the main research sample and Camellia sinensis cv. Tieguanyin and Camellia sinensis cv. Shuixian were used as the controls. Ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) was used for non-targeted metabolomics analysis to screen differential compounds in the oolong teas made from different cultivars. In addition, ultra-high performance liquid chromatograph, amino acid analyzer and ultra-high performance liquid chromatography-quadrupole-orbitrap-mass spectrometry (UHPLC-Q-Orbitrap-MS) was applied for absolute quantifications of main chemical constituents and differential compounds in oolong teas made from different cultivars. 【Result】 Compared with the control oolong teas of same scent type, YCFS oolong tea had relatively higher contents in total amino acid and theanine. The contents of total catechins and caffeine were not significantly different among the 3 cultivars in fresh-scent and strong-scent oolong teas, and were highest in YCFS in aged-scent oolong teas. The content of gallic acid was SX>YCFS>TGY in 3 scent types oolong teas. Metabolomics analysis combined with multivariate statistics analysis shows that the compound patterns in oolong teas made from different cultivars were significantly different. There were 50, 59, and 47 differential compounds between YCFS and control cultivars in fresh-scent, strong-scent and aged-scent oolong teas, respectively. Among them, 23 differential compounds were common, including 14 flavone (flavonol) glycosides, 5 catechins and their derivatives, 1 lipid, 1 alkaloid, 1 organic acid and 1 amino acid. Further quantitative analysis of 20 main flavone (flavonol) glycosides showed that the contents of 14 flavone (flavonol) glycosides are highest in YCFS oolong teas, whose contents were 1.4 to 14.6-fold of that in TGY oolong teas and were 1.3 to 18.0-fold of that in SX oolong teas. Among four kinds of flavone (flavonol) glycosides, quercetin glycosides were the main flavone (flavonol) glycosides with higher contents than glycosides of kaempferol, myricetin and apigenin. Sensory evaluation combined with chemical composition results showed that the higher contents of flavone (flavonol) glycosides did not significantly enhance the astringency of YCFS oolong tea infusions. 【Conclusion】 The metabolomics method effectively characterized the component differences in oolong teas made from different cultivars in this study. There were obvious differences in compound patterns among YCFS, TGY and SX oolong teas. Flavone (flavonol) glycosides were the most significantly differential compounds. The higher content of flavone (flavonol) glycosides is a major chemical feature of YCFS oolong tea and is expected to be used as a discriminant index for the identification of oolong tea cultivar in the future.


]]> <![CDATA[Sequence Analysis of <i>Harmonia axyridis</i> Pyruvate Kinase Gene and Regulation of Trehalose Metabolism]]> 】Pyruvate kinase (PYK) is a glycolytic enzyme that regulates the balance between glycolysis and gluconeogenesis, so it has an important physiological role in insects. This study aims to explore the biological functions of HaPYK in Harmonia axyridis by analyzing the sequence structure of the three HaPYKs and RNA interference technology. 【Method】Based on the three HaPYK sequences obtained from the whole genome of H. axyridis (named HaPYK1-1, HaPYK1-2, HaPYK2, respectively), we analyzed its physicochemical properties, sequence structure and homology with other insects through bioinformatics knowledge. Then, the dsRNA synthesized in vitro was injected into the adult on the first day of emergence by microinjection. The experimental materials were collected 48 and 72 h after injection, and the total RNA extraction and reverse transcription experiments were performed. In order to evaluate the inhibitory effect, we used real-time fluorescent quantitative PCR technology to determine the expression levels of three HaPYKs. Finally, the expression levels of genes related to trehalose metabolism, the content of glucose, glycogen, trehalose, and the activities of two trehalase enzymes were detected. 【Result】The experimental data showed that the open reading frames of HaPYK1-1, HaPYK1-2 and HaPYK2 were 1 350, 1 569 and 1 656 bp, respectively. The protein sizes were 449, 522 and 551 aa, and the theoretical isoelectric points were 5.04, 5.02 and 5.01, respectively. The conserved domains predicted that the three HaPYKs belonged to the pyruvate_kinase superfamily. The secondary structure of HaPYK was mainly α-helix and random coil, but also contained extended chain and β-corner. The oligomer types of the three sequences were all homologous tetramer. The phylogenetic tree showed that HaPYK was closely related to the same coleoptera insects, such as Leptinotarsa decemlineata and Tribolium castaneum. In addition, after injection of dsHaPYK1-1, the expression levels of HaPYK1-2 and HaTRE1-4 were significantly down-regulated, while the expression levels of HaPYK2, HaTRE1-1, HaTRE1-2, HaTRE2-like, and HaTPS were significantly up-regulated; after injection of dsHaPYK1-2, the expression of HaTRE1-1, HaTRE1-2, HaTRE1-3, HaTRE1-5, HaTRE2, HaTPS increased significantly; after injection of dsHaPYK2, only HaTRE1-1 was significantly up-regulated at 48 h, and the expression levels of HaTRE1-3, HaTRE1-4, HaTRE1-5, HaTRE2, HaTRE2-like were down-regulated. Compared with the control group, in the dsHaPYK1-2 group, the activity of TRE1 reduced significantly at 48 h, and the content of trehalose and glycogen was increased significantly; in dsHaPYK1-1 or dsHaPYK2, the glucose content decreased at 48 h, the glucose and trehalose content increased at 72 h, and the enzyme activity of TRE2 was increased significantly; at 48 h in dsHaPYK2 group, trehalose significantly reduced, but a significant increase in glycogen content.【Conclusion】There are three HaPYKs in H. axyridis. By injecting exogenous dsHaPYK, the expression level of target genes can be successfully reduced. Suppressing their expression levels could affect the metabolism of trehalose, and the regulatory mechanisms of the three HaPYKs are not the same. The above results provide theoretical basis and help for further research on the energy metabolism of H. axyridis and other biological functions of HaPYK in H. axyridis.

]]> <![CDATA[Uniform Distance Single Seed Linear Seeding Method for the Control of Wheat Physiology and Ecology]]>

]]> <![CDATA[The Photosynthesis Characteristics of Rice Leaves with Different Colors and its Relation with Antioxidant Capacity, Anthocyanin Content]]> ied and response mechanisms were revealed.【Result】The results indicated that the highest chlorophyll content was showed in DP, followed by the DG and FP, while the lowest value were found in FG. Under this case, the FG variety attained the highest value of actual fluorescence quantum efficiency of PSII, photosynthetic rate, ribulose-1, 5-bisphosphate carboxylase activity and total dry matter weight, which was significantly higher than the other varieties. The content of hydrogen peroxide and malondialdehyde in FG leaves was significantly lower than other rice varieties. Besides, there is no significant difference in leaf chlorophyll content and carotenoid content between DP and DG, while the actual fluorescence quantum efficiency of PSII, net photosynthetic rate, ribulose-1,5-diphosphate carboxylase activity in leaves of DP were significantly higher than those of DG. Correspondingly, activities of antioxidant enzymes in leaves of DP were significantly higher than those of DG, while the content of hydrogen peroxide and malondialdehyde were significantly lower than DG. This may be related to the anthocyanin content in the leaves, because the anthocyanin content in the leaves of DP was significantly higher than that of DG. The leaf photosynthetic rate was significantly increased and hydrogen peroxide content was significantly decreased after foliar application of anthocyanin. 【Conclusion】Therefore, it was inferred that anthocyanin might exert important role in alleviating the inhibition effect caused by excess opical quantum on the photosynthesis of leaves under natural conditions. The results could provide a theoretical basis for rice high light efficiency breeding and exploitation for high quality and high efficiency cultivation technology of colored rice.]]> <![CDATA[Effects of Long-term Intercropping of Corn with Hairy Vetch on Crop Yield and Nitrogen Fertilizer Contribution Rate Under Nitrogen Fertilizer Reduction]]>  and its stubble returning on corn yield and nitrogen fertilizer contribution rate under nitrogen fertilizer reduction were studied, in order to provide scientific basis for nitrogen fertilizer substitution and nitrogen resource efficient management in corn/hairy vetch intercropping system.【Method】The field experiment was carried out in 2014-2019 at scientific observing and experimental station of arable land conservation and agriculture environment of Gansu province, ministry of agriculture monocropped corn treatment was set under the levels of no fertilization and conventional nitrogen fertilization, the intercropping system of corn with hairy vetch were set under 90%, 80%, 70%, 60% and 0% of conventional nitrogen application levels, and there were 7 treatments and 3 replicates in a field experiment with a randomized block design. The changes of crop yield, economic benefits, partial productivity of nitrogen fertilizer, nitrogen agronomic efficiency and nitrogen fertilizer contribution rate were studied in long-term intercropping of corn with hairy vetch under different nitrogen fertilizer reduction.【Result】The results showed that, the long-term intercropping system of corn with hairy vetch and hairy vetch stubble returning had the obvious advantage of increasing corn yield, the yield increase advantage increased with the lengthening of intercropping years..Compared with conventional nitrogen fertilization, the hay yield of hairy vetch could be increased by 2273.20 kg·hm-2 under the condition of ensuring stable corn grain yield, the total profit was 29 686 yuan/hm2 and increased by 0.89%, partial productivity of nitrogen fertilizer and nitrogen agronomic efficiency were significantly increased by 20.69% and 14.65% in the long-term intercropping system of corn with hairy vetch and hairy vetch stubble returning under the condition of reduced 20% nitrogen fertilizer. Compared with conventional nitrogen fertilization, although the corn grain yield was significantly reduced by 7.74%, the hay yield of hairy vetch could be increased by 2319.34 kg·hm-2, the total profit was 28 652 yuan/hm2, which was equivalent to that of conventional nitrogen fertilization, partial productivity of nitrogen fertilizer and nitrogen agronomic efficiency were significantly increased by 31.79% and 16.30% in the long-term intercropping system of corn with hairy vetch and hairy vetch stubble returning under the condition of reduced 30% nitrogen fertilizer. Compared with conventional nitrogen fertilization, although the hay yield of hairy vetch could be increased by 2303.09 kg·hm-2, partial productivity of nitrogen fertilizer and nitrogen agronomic efficiency were significantly increased by 48.78% and 23.75%, but the corn grain yield was significantly decreased by 10.71%, the total profit was only 27 929 yuan/hm2, which was significantly lower than that of conventional nitrogen fertilization in the long-term intercropping system of corn with hairy vetch and hairy vetch stubble returning under the condition of reduced 40% nitrogen fertilizer.【Conclusion】If only corn grain yield was considered, 20% chemical nitrogen fertilizer can be substituted, and if total output value of maize and hairy vetch was considered, 30% chemical nitrogen fertilizer can be substituted, in corn/hairy vetch intercropping and hairy vetch stubble returning for 9 years under nitrogen fertilizer reduction in the production process of corn in Hexi oasis irrigation area.


]]> <![CDATA[Effects of Arbuscular Mycorrhizae Fungi on soil N2O Emissions During Maize Growth Periods]]> 2O) emissions, could provide theoretical basis for increasing maize yield, improving nitrogen (N) use efficiency and reducing greenhouse gas emissions. 【Methods】 A 2-factorial greenhouse experiment was established during maize growth periods in 2016 and 2017. The factors were as follows: (1) N fertilizer rates (180 kg N hm-2 [N1] and 360 kg N hm-2 [N2]), and (2) three mycorrhizae treatments, including a control (M0, neither roots nor AMF could enter the hyphal chamber from the growth chamber), an AMF treatment (M1, only AMF can enter the hyphal chamber from the growth chamber), and a root treatment (M2, both roots and AMF can enter the hyphal chamber from the growth chamber). Maize grain yield, plant biomass and their N accumulation, and soil N2O flux were measured. Soil bacterial community structure and diversity at maize maturity stage was determined using the high throughput sequencing technique on Hiseq 2500 PE250. 【Results】 Both N fertilizer rates and mycorrhizae treatments significantly affected maize yield, plant N accumulation and soil N2O flux. Compared with the M0, maize yield of M1 and M2 under the conditions of N1 input increased by 38% and 82%, by 30% and 52% for aboveground N accumulation, and reduced by 26% and 65% for soil inorganic N, respectively. However, under the conditions of N2 input, maize yield of M1 and M2 increased by 16% and 48%, by 9% and 33% for aboveground N accumulation, and reduced by 34% and 55% for soil inorganic N, respectively. Compared with the M0, the total N2O emission of M1 and M2 treatments reduced by 17% and 40% under the conditions of N1 input, and by 41% and 67% for the N2O emission intensity, respectively, while under the conditions of N2 input, the total N2O emission reduced by 26% and 45%, and by 28% and 57% for the N2O emission intensity, respectively. Nonmetric multidimensional scaling analysis showed that both N fertilizer rates and mycorrhizae treatments had significant effects on bacterial communities’ composition. Compared with N1, the relative abundance of Proteobacteria and Gemmatimonadetes for N2 treatment on phyla level reduced by 6% and 15%, increased by 32% for Actinobacteria, while on genera level, the Streptomyces increased by 27%, and reduced by 8% for Gemmatimonas. Compared with M0, the relative abundance of Streptomyces in M1 and M2 increased by 64% and 205%, by 31% and 53% for Gemmatimonas, under the conditions of N1 input, however, under the conditions of N2 input, the relative abundance of Streptomyces of M1 and M2 increased by 10% and 93%, the Gemmatimonas for M1 reduced by 2%, and increased by 56% for M2. Moreover, the relative abundance of soil Streptomyces and Gemmatimonas was negatively related with soil N2O emission, but positively related with maize yield. 【Conclusion】 Arbuscular mycorrhizae fungi could reduce soil N2O emission under both higher and lower N fertilizer application rate, and the reduce mainly through increasing the maize N uptake, and regulating the bacterial composition, especially increasing the relative abundance of Streptomyces and Gemmatimonas.


]]> <![CDATA[The Spatial and Temporal Evolution, Regional Correlations and Economic Coordinated Development Effect for Chinese Agricultural Science and Technology Level: Taking Provincial Public Agriculture Research Institutions as an Example]]> 】In the long run, agricultural science & technology and agricultural economics should show a dynamic and mutually beneficial collaborative development trend, which is more conducive to accelerating the development of modern agriculture. To study further the spatial and temporal evolution trends and spatial distribution characteristics of science and technology development of pubic agriculture research institutions, and the coordinated development condition between agricultural science & technology and regional economics, contributes to correctly understand the coordinated development mechanism of agricultural science & technology innovation and regional economy among provinces, and analyze the potential reasons for the poor coordinated development degree of agricultural science & technology and agricultural economy, and  explore to find the way to improve the agricultural science & technology innovation level and resolve the problem of “wide gap between agriculture S&T and agriculture economy”.【Method】Based on numbers of agricultural researchers, the patent grants and numbers of published papers, the GIS technology and ESDA methods are applied for the study of spatial and temporal evolution trends and spatial distribution characteristics of science and technology output by provincial public agriculture research institutions, and coordinated development condition between agricultural science & technology and agricultural economics is revealed. 【Result】 The results show that: During ten years, the science and technology output of provincial public agriculture research institutions are decreasing gradually from the eastern coastal areas to the surroundings; the patent grants are increasing obviously for most provincial agriculture research institutions, while the quantity growth of publication of papers and the agricultural researchers are indistinctive. From the perspective of spatial distribution characteristics, notwithstanding the science and technology output of provincial public agriculture research institutions present the characteristics of local spatial autocorrelation, large-scaled spatial agglomeration effects are not formed. From the perspective of coordinated development condition between agricultural science & technology and agricultural economics, the Eastern cities by Shandong, Jiangsu, Guangdong, Fujian etc. had good performance, the central regions is average and the coordinated development condition between agricultural technology and agricultural economics for the most provinces in Northwest, Southwest and Northeast China are weak. Hereby some policy proposals are put forwarded in aspect of improving the level of science and technology of provincial public agriculture research institutions, and promoting the coordinated development condition between agricultural science & technology and agricultural economics.【Conclusion】During 2008-2018, the science & technology level of provincial public agriculture research institutions gradually decreased from the eastern coastal areas to the surroundings, showing the features of spatial heterogeneity, and large-scaled spatial agglomeration effects has not been formed. The coordinated development degree between agricultural science & technology level of provincial public agriculture research institutions and provincial agricultural economics is lower, consequently, it is necessary to accelerate the construction of the spatial agglomeration pattern of the coordinated development of agricultural science & technology and agricultural economics, which provides support for solving the problem of “wide gap between agriculture S&T and agriculture economics”.]]> <![CDATA[Resources Inputs and Ecological Environment Risks Assessment of Maize Production in Northwest China]]> Objective】Northwest China is rich in land resources and is one of the four major maize production areas in China. It is critical to clarify the resource inputs and ecological environmental risks of maize production in this region.【Method】 Based on the life cycle assessment (LCA) method to evaluate resource inputs (fertilizer, pesticide, diesel, mulch, seed, and labor) and ecological environment risks (greenhouse gas emissions, soil acidification, water eutrophication and human toxicity) of maize production in six provinces (Xinjiang, Shaanxi, Shanxi, Ningxia, Inner Mongolia, Gansu) of Northwest China during the past 15 years (2004-2018), and quantitatively evaluate the resource inputs, ecological environmental risks and spatiotemporal variations of maize production per unit area (per hectare) in this resources.【Result】Resource inputs and ecological environment risks of maize production were high in Northwest China. The average fertilizer input in past 15 years was 233.1 kg N·hm-2, 106.3 kg P2O5·hm-2, 23.3 kg K2O·hm-2, the pesticide, diesel, mulch, seed and labor inputs were 6.5 kg ·hm-2, 93.2 L·hm-2, 13.7 kg·hm-2, 38.8 kg·hm-2 and 120.1 h·hm-2, the average yield was 7.9 t·hm-2. The averaged greenhouse gas emissions was 4188 kg CO2-eq·hm-2, the soil acidification potential was 155.3 kg SO2-eq·hm-2, the water eutrophication 52.6 kg PO4-eq·hm-2, and the human toxicity was 2.9 kg 1, 4-DCB-eq·hm-2. Compared with 2004, the overall resource input for maize production of Northwest China in 2018 was increased, showing an overall increased trend. The rates of nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer per unit area increased by 9.2%, 52.7% and 203.7%, respectively; and the rate of pesticide, diesel oil and mulch per unit area increased by 303%, 143% and 108%, respectively. The rates of seed and labor per unit area decreased by 38.6% and 50.8%, while the planting area and maize yield increased by 79% and 26.9%, respectively. On the whole, the multiple ecological environment risks showed a first increased and then decreased trend, in which the greenhouse gas emissions, soil acidification potential, water eutrophication potential and human toxicity per unit area increased by 13.6%, 15.8%, 2.6% and 302.5%, respectively. Among the 15 years of maize production in Northwest China, the highest nitrogen fertilizer input and greenhouse gas emissions per unit area were observed in 2016, and the lowest were observed in 2007. The resources inputs and ecological environment risks of maize production in different provinces of Northwest China were significantly different. In terms of unit area, the rate of nitrogen fertilizer, mulch and labor input was highest in Gansu, and lowest in Shanxi, Shaanxi and Inner Mongolia, respectively. The rate of phosphorus fertilizer and diesel was highest in Xinjiang, and the lowest was Shaanxi. The rate of potassium fertilizer was highest in Shanxi and lowest in Xinjiang. The rate of pesticides and seeds was highest in Ningxia and Xinjiang, and lowest in Shanxi. The planting area and maize grain yield were highest in Inner Mongolia and Xinjiang, and lowest in Ningxia and Shaanxi, respectively. Simultaneously, the greenhouse gas emission and soil acidification potential were highest in Gansu, the water eutrophication potential was highest in Shaanxi, and the human toxicity was highest in Ningxia and lowest in Shanxi. The comprehensive value of resources inputs and ecological environment risks for maize production in Northwest China was highest in Ningxia. Shanxi achieved the lowest comprehensive value of ecological environment risks for maize production in Northwest China. 【Conclusion】Maize production in Northwest China is characterized by "high input, high yield and high risk", the resource inputs and ecological environment risk are quite different in different spatiotemporal scale. During 2004 to 2018, the planting area, grain yield, and resources input were totally increased slightly, while the ecological environment risk showed a first increased and then decreased trend. Maize production can be considered to incline to high-yield and low-environmental risk areas in the future. Simultaneously, optimizing the fertilizers rate, applying enhanced efficiency fertilizers, and adopting systematic management strategies would lead to achieve high yields and low ecological environment risks.]]> <![CDATA[Identification of Co-expression Gene Related to Tea Plant Response to Glyphosate Based on WGCNA]]> C. sinensis cv ‘Jin-guanyin’ was applied as material plant. A recommended concentration of glyphosate was irrigated to test plants.Samples were collected at different time intervals (0, 0.25, 1, 3 and 7 d). The samples were sequenced by transcriptome, the content of shikimic acid was also quantified.The WGCNA method was used to jointly analyze transcriptome and shikimic acid content data, identify co-expressed gene modules related to glyphosate response, and screen out key regulatory genes.【Results】the content of shikimic acid in tea leaves reduced gradually during first 3 days. However, it suddenly reached a peak on the 7th day( 6.99 times compared to no glyphosate treated sample).A total of 12568 differential expression genes (DEGs) were also identified,whichmainly enriched in phenylpropane, flavonoid biosynthesis and plant hormone signal transduction pathways. In addition, glyphosate treatment induced 24, 52, 31 and 69 genes respectively which related to shikimic acid metabolism, phenylpropane, flavonoid biosynthesis and hormone signal transduction pathways. A total of 19 modules were screened out by WGCNA method. Correlate analysis of transcriptome and shikimic acid content indicated two key modules which including 2024 and 2305 genes, respectively. The top 50 genes with the highest connectivity in the key modules were selected for co-expression analysis, and 6 key response genes were obtained, including 2 resistance genes (SHMTandRPM), 1 drug resistance gene (PDR), 1 ion transport gene (At), 1 membrane transport gene (GPT) and 1 transcription factor gene (ERF). 【Conclusion】Glyphosate could affect downstream genes transcription of phenylpropane, flavonoid biosynthesis and hormone signal transduction pathways by interfering shikimic acid metabolism of tea plants.In addition, the study also identified two co-expression modules closely related to glyphosate response, and found that multiple potential candidate genes and transcription factors can resist glyphosate stress, such asSHMT, RPM, At, PDR, ERFandGPT.]]> <![CDATA[Preparation of Pesticide-Degrading Bacteria-Immobilized Sodium Alginate Microspheres and Their Bioremediation of Indoxacarb Residues]]> Pseudomonas stutzeri microsphere preparation with sodium alginate as carrier and establish the application conditions of the preparation for degrading indoxacarb in farmland soil. 【Method】The best formulation was obtained by the method of micro droplet embedding and single factor optimization, and the stability and degradation activity of the preparation were tested to determine the field application conditions. 【Result】The preparation was composed of 3% sodium alginate, 2% calcium chloride and 80 g?L-1degrading bacteria with a particle size of 3.0 mm, high degrading activity and good stability. Scanning electron microscopy showed that the degrading bacteria were evenly distributed in the alginate microspheres, and the morphology of the bacteria was normal. The degradation rate of indoxacarb reached more than 95% in the soil with pH 5.0-9.0 and 10-40℃, and the release performance was not affected by the soil type. Field experiments showed that the half-life of indoxacarb in soil was significantly shortened to 7.9-8.8 d when the dosage of indoxacarb was 450 kg?hm-2. 【Conclusion】When the concentration of sodium alginate was 3%, the concentration of calcium chloride was 2%, and the amount of entrapped bacteria was 80 g?L-1, the size of the microspheres was uniform, the mechanical strength was moderate, and the mass transfer performance was good. The distribution of degrading bacteria in alginate microspheres was uniform and the morphology of bacteria was normal. The results showed that the release ability and stability of the preparation were good, little affected by environmental conditions, and good storage stability. The field experiment showed that the half-life of indoxacarb in soil could be significantly shortened to 7.9-8.8 d when the dosage of indoxacarb was 450 kg?hm-2. The field application effect was good, which provided technical and product support for bioremediation of soil indoxacarb pesticide residue pollution, and had further optimization potential and broad application prospect.]]> <![CDATA[Expression <span>p</span>rofile of G <span>p</span>rotein-<span>c</span>oupled <span>r</span>eceptor <span>k</span>inase 2 <span>g</span>ene (<i>AlGRK2</i><span>) </span>and <span>i</span>ts <span>f</span>unction in the <span>d</span>evelopment of <i>Apolygus lucorum</i>]]> Apolygus lucorum, and analyzed its expression profiles. We also clarified the effect of AlGRK2 expression under exogenous ecdysterone hormone 20E in A. lucorum and the role of AlGRK2 in the development of A. lucorum nymphs, laying the foundation for further research on its function in the ecdysone signaling pathway.【Method】We cloned and obtained the AlGRK2 in A. lucorum by RACE method. Using the qRT-PCR method, we determined the relative expression levels of AlGRK2 in different days old (1-16 day) and different tissues (head, thorax, wings, legs, midgut, ovary and fat body) in female adults in A. lucorum. Finally, We analyzed the response of the AlGRK2 in A. lucorum after exogenous 20E induction and RNAi treatment and its effects on the developmental duration of the nymphs, the weight of the 5th instar nymphs and the emergence rate of adults.【Result】The full length of AlGRK2 cDNA is 2 715 bp, and ORF is 2 106 bp. ExPASy predicts that the protein molecular weight is 80.2 kD. Protein structure analysis shows that AlGRK2 contains 4 domains and has the typical domain in the GRK2 protein (PH domain). qRT-PCR results showed that AlGRK2 was expressed in 1-day-old to 16 day-old nymphs of A. lucorum, in which the expression level was the highest at 1th day-old and the lowest at 14-day-old. The AlGRK2 gene was highly expressed in the ovary, midgut, and fat body of female adults and less expressed in the thorax and legs. After exogenous 20E treatment, the expression of AlGRK2 was significantly down-regulated in nymphs at the 1-day-old and the 3-day-old. The relative expression of AlGRK2 in all tissues of females was up-regulated after treating with 20E which compared with control, especially in ovary and fat body. Compared with CK, the developmental duration of nymph, the body weight of the last instar nymph and the emergence rate of adult in A. lucorum were significantly decreased after 20E treatment. In addition, AlGRK2 expression level of A. lucorum significantly decreased in the dsAlGRK2 group compared with the dsGFP group. Compared with the dsGFP group, the mortality rate and the 5th instar developmental period of the dsAlGRK2 group of A. lucorum nymph increased significantly, while the adult emergence rate and the 5th instar nymph body weight decreased significantly.【Conclusion】The expression profile of AlGRK2 in A. lucorum showed the specificity of the developmental stage and the tissue. Exogenous 20E treatment can inhibit the expression of AlGRK2 gene in A. lucorum and delay the growth and development of A. lucorum, and RNAi also shows similar effects. The results provide a theoretical basis for revealing the function of GRK2 and perfecting the ecdysone signal pathway, and laying a foundation for providing new targets for pest control.]]> <![CDATA[Establishment and A<span>pplication of A</span><span> D</span><span>uplex ddPCR M</span><span>ethod to Q</span><span>uantify the NK603/</span><i><span>zSSIIb</span></i> C<span>opy N</span><span>umber R</span><span>atio in T</span><span>ransgenic M</span><span>aize NK603</span>]]> an important target of genetically modified organism (GMO) regulation in China. The implementation of GMO regulation requires reference materials (RMs) and standardized detection methods. Establishment of a duplex droplet digital PCR (ddPCR) would provide accurate measurement technology for quantification of NK603 event and development of NK603 RMs. 【Method】A standard plasmid molecule pUC57-NK603 was constructed by DNA synthetic technique; the primer/probe set of NK603 event was combined with different maize reference genes one by one to select reference gene PCR assay with identical amplification ability to NK603 event-specific PCR assay; main reaction parameters, such as annealing temperature and primer/probe concentration，were optimized in the course of establishing duplex ddPCR; the standard plasmid solution was serially diluted to investigate the limit of detection (LOD), limit of quantification (LOQ) and dynamic range of the duplex ddPCR assay; blinded samples with mass fractions of 100%, 10% and 6% were prepared by mixing NK603 powder with non-GM counterpart, to evaluate the accuracy of quantitative results of the duplex ddPCR. 【Result】 The reference gene zSSIIb was determined to combine with NK603 event to establish the NK603/zSSIIb duplex ddPCR method with the standard plasmid molecule pUC57-NK603 as a quality control after analyzing the fluorescence amplitude of positive droplets, separation between positive and negative droplets, raindrop number, and consistency between measured copy number ratio and expected copy number ratio of NK603 event to reference gene. The primer/probe concentration was optimized to be 400 nmol·L-1/200 nmol·L-1 for both NK603 event and zSSIIb gene, and the annealing temperature was determined to be 60°C. The LOD of NK603/zSSIIb duplex ddPCR was estimated to be 2 copies of DNA template, the LOQ was 48 copies of DNA template, both NK603 assay and zSSIIb assay showed good linearity between measured values and theoretical values over the dynamic range from 10 to 60000 copies of DNA template. The NK603/zSSIIb duplex ddPCR achieved accurate quantitative results of NK603 content in blinded maize samples with less than 25% of coefficient of variation; the quantitative results of ddPCR were not significantly different from those of real-time quantitative PCR (qPCR), moreover, the duplex ddPCR showed an advantage over qPCR in term of precision. 【Conclusion】 The selection of reference genes affects the accuracy of quantitative results by ddPCR. Establishment of ddPCR methods should use samples with accurate GMO content as quality controls to evaluate the applicability of reference genes. The NK603/zSSIIb duplex ddPCR method was successfully established using the synthetic standard plasmid molecule pUC57-NK603 as a quality control. NK603 certified reference materials (CRMs) have been successfully developed in China by applying the established NK603/zSSIIb duplex ddPCR assay to characterize the property values.


]]> <![CDATA[Over-expression of <em>ZmIBH1-1</em> to Improve Drought Resistance in Maize Seedlings]]> Objective】Drought is an important factor that affects the growth and development of maize seriously. Through the mining of genes related to drought resistance in maize, transgene function verification and transcriptome analysis, analyze the molecular regulation mechanism of key genes in response to drought stress provides the theoretical basis for drought resistance molecular breeding and genetic improvement. 【Method】In this study, the maize inbred line B104 (wild-type, WT) was used as the background to construct the ZmIBH1-1 overexpression (ZmIBH1-1-OE) transgenic line by Agrobacterium-mediated method. The transgenic plants and lines were identified via screening transgenic plants for glufosinate-ammonium resistance, PCR detection of marker gene and target gene and expression analysis of target gene by qRT-PCR. We using the ZmIBH1-1-OE and WT transgenic lines as materials. Through drought treatment (20% PEG6000), phenotype identification and drought tolerance physiological and biochemical index determination were carried out to verify the drought resistance function of ZmIBH1-1; RNA-Seq was used to identify differentially expressed genes (DEGs) under drought stress at the 4-leaf stage; Combined with DAP-seq (DNA affinity purification sequencing) analysis, it is preliminarily determined that ZmIBH1-1 protein directly regulates downstream target genes related to drought resistance, and IGV (Integrative Genomics Viewer) was used to analyze the position of the ZmIBH1-1 protein binding candidate target gene, and then the Dual-Luciferase assay was used to verify the regulatory relationship between ZmIBH1-1 protein and target genes. 【Result】12 transformation events were obtained by genetic transformation of maize. In the T3 generation, there were 458 plants in which the marker gene Bar and the target gene ZmIBH1-1 were simultaneously detected. The results of qRT-PCR showed that the expression level of ZmIBH1-1 in ZmIBH1-1-OE lines was significantly higher than that of WT and the expression levels of transformation events 3 and 8 were the highest, which were self-crossed to obtain T4 generation for subsequent experiments. Under drought stress, the survival rate, the relative water content, the chlorophyll content, soluble protein content and the physiological and biochemical indicators (superoxide dismutase, peroxidase, catalase activity) of ZmIBH1-1-OE were higher than those of WT significantly, which indicating that the overexpression of ZmIBH1-1 in maize confers higher drought tolerance. The RNA-Seq results showed that there were 1 214 DEGs between WT and ZmIBH1-1-OE lines. Gene Ontology (GO) analysis showed that DEGs were mainly involved in biological processes, cell components and molecular functions, such as photosynthesis, stress response, dehydration response, etc. in biological processes; KEGG enrichment analysis showed that DEGs were mainly involved in the signal transduction of plant hormones, the metabolism and other processes. Combining the significantly DEGs of RNA-Seq and the target genes of ZmIBH1-1 obtained from DAP-seq analysis, it is preliminary identified 11 candidate target genes related to drought resistance that may be directly regulated by ZmIBH1-1, including 2 calcium signal related genes, 3 cysteine metabolism related genes, 1 bHLH transcription factor, 1 stress response protein, 1 glutathione transferase, 1 redox process protein and 2 ethylene response factor; Integrative genomics viewer showed that ZmIBH1-1 protein could bind to the promoters of the target genes; Subsequent Dual-Luciferase assay further showed that ZmIBH1-1 protein can directly act on 11 candidate target genes, of which, ZmIBH1-1 directly binds to the promoters of ZmCa-M, ZmSYCO, ZmbHLH54, ZmGlu-r1, ZmCLPB3 and ZmP450-99A2 to promote their expression, and directly binds to the promoters of ZmAGD12, ZmCYS, ZmCYSB, ZmERF-107 and ZmEIN3 to repress their expression. In addition, transcription factors such as NAC, WRKY and MYB also differentially expressed between WT and ZmIBH1-1-OE under drought stress. 【Conclusion】The overexpression of ZmIBH1-1 can enhance the drought tolerance of maize; ZmIBH1-1 improves the drought tolerance of maize by directly regulating the expression of genes ZmERF-107 and ZmEIN3 in the ethylene signaling pathway; ZmIBH1-1 enhances the drought tolerance of maize by directly regulating the calcium signal-related genes ZmCa-M and ZmAGD12; ZmIBH1-1 may indirectly regulate NAC, WRKY, MYB and other transcription factors in response to drought stress.


]]> <![CDATA[IbMKP6, A Mitogen-Activated Protein Kinase, Confers Low Temperature Tolerance in Sweetpotato]]> 】Studying the function of mitogen activated protein kinase (MAPK) IbMPK6 in respect of low temperature stress tolerance in sweetpotato, that will help us to understand the mechanism of adaption to low temperature stress and play a fundamental role in molecular breeding of sweetpotato.【Method】Agrobacterium tumefaciens strain EHA105 harbored the plasmid 35S::IbMPK6-GFP were transformed intosweetpotato cv. Xushu29 embryogenic callus. Molecular examination and qRT-PCR were used to screen and select transgenic lines. For low temperature stress assay, selected transgenic lines were performed to observe the phenotype and determine the physiological indexes such as Fv/Fm, the content of malondialdehyde (MDA) and hydrogen peroxide (H2O2) after low temperature treatment and recovery treatment. Diaminobenzidine (DAB) staining and nitro blue tetrazolium (NBT) staining analysis were performed to observe reactive oxygen species (ROS) accumulation. The expression level of the key transcription factor IbCBF3 and downstream gene IbCOR27 involved in low temperature signal transduction pathway were identified before and after low temperature treatment.【Result】Twelve transgenic lines were generated and three transgenic lines (L3, L8 and L11) with a high expression level of IbMPK6 were selected for low temperature tolerance assay. Under low temperature stress, the level of Fv/Fm in transgenic lines L3, L8 and L11 was 0.79, 0.79 and 0.80, while that in WT was 0.05. After temperature recovery treatment, Fv/Fm in transgenic lines has recovered to former levels, whereas the level of Fv/Fm in WT was only 0.70, which was significantly lower than that in transgenic lines. MDA content of three transgenic (lines L3, L8 and L11) increased by 0.02 μmol·g-1, 0.04 μmol·g-1 and 0.02 μmol·g-1, and it of WT increased by 0.05 μmol·g-1 after low temperature stress treatment, respectively. After recovery treatment, MDA content in transgenic lines was 0.01 μmol·g-1 on average, whereas it of WT was 0.03 μmol·g-1. The results of DAB and NBT staining showed that the leaves of WT were stained deeper than those of transgenic lines, indicated that hydrogen peroxide and superoxide anion were accumulation less in transgenic lines than in WT. Furthermore, H2O2 level in WT was significantly higher than that in transgenic lines under low temperature stress condition and after recovery treatment. Low temperature regulated the expression level of IbCBF3 and IbCOR27 genes, but the expression level in transgenic lines was higher than that in WT.【Conclusion】Overexpression of IbMPK6 in sweetpotato resulted in enhanced tolerance to low temperature stress, via alleviating the damage of membrane and photosynthetic system, and decreasing ROS accumulation. IbMPK6 involved in low temperature signaling transduction pathway by up-regulating the expression level of cold related genes IbCBF3 and IbCOR27.


]]> <![CDATA[Effects of PvEG261 gene on the Fusarium wilt and drought-resistance in common bean]]> 】By analyzing the sequence and expression pattern characteristics of PvEG261 from common beans, and studying its resistance to Fusarium wilt and drought, the foundation was laid for the signal regulation network analysis of Fusarium wilt and drought-resistance and molecular breeding in common beans. 【Method】 Bioinformatics analysis was performed on the open reading frame (ORF) of PvEG261 to predict the physical and chemical properties, secondary structure, signal peptide sequence of the protein encoded by the PvEG261, and search for highly homologous protein sequence in NCBI database through Blastp tool online for sequence alignment and phylogenetic tree construction; the tissue expression specificity of PvEG261 and the expression pattern in response to Fusarium wilt pathogen and drought stress were analyzed by qRT-PCR; PvEG261 overexpression vector was constructed and transformed into Agrobacterium rhizogenes K599 to induce the generation of hairy transgenic roots in common beans. Meanwhile, the PvEG261 silencing vector was constructed, and the transcription product in vitro was inoculated on the seedlings of common bean to interfere with PvEG261 expression. Through inoculation with the pathogen and drought treatment, the phenotypes of control, PvEG261-overexpressed and silenced plants were observed, disease and drought-resistance were both identified, and hydrogen peroxide (H2O2) content, malondialdehyde (MDA) content, superoxide dismutase (SOD) and peroxidase (POD) activity as physiological and biochemical indicators were all assayed. 【Result】 The cDNA sequence of PvEG261 was 471 bp, which encodes a protein composed of 156 amino acids. The structure prediction indicated that it contained 10 strand structures, the predicted molecular mass of the encoding product was 38.89 kD, and the theoretical pI was 5.21. PvEG261 belonged to the members of dirigent gene superfamily, it contained a signal peptide sequence of 10 amino acids, and belonged to a secreted protein. The relationship between PvEG261 and cowpea DIR22 protein is the closest, which reached 91.61%. The results of qRT-PCR showed that the expression in the root tissues increased significantly after inoculation with Fusarium wilt pathogen and drought treatment, and the gene has obvious tissue expression specificity, with the highest expression level in the roots. After inoculation with pathogen and drought treatment, the disease and drought-resistance of the overexpressed plants were significantly improved in comparison with the control, the plant disease scores and the wilting degree caused by water shortage were significantly reduced, and the H2O2 content, POD and SOD activity in the roots were all significantly higher than the control plant, while the MDA content was dramatically lower than the control plant. The disease and wilting degree of the gene silenced plants were significantly increased. The H2O2 content, POD and SOD activity in the roots were significantly lower than the control plant, and the MDA content was significantly higher than the control plants.【Conclusion】PvEG261 responded to Fusarium wilt pathogen infection and drought stress, and positively regulated the Fusarium wilt and drought-resistance in common beans.]]> <![CDATA[Annual Nutrients Balance and Economic Return Analysis of Wheat with Fertilizers Reduction and Different Rotation in Guanzhong Plain, Shaanxi]]> , including four treatments: corn-wheat rotation with farmer accustomed fertilization (CWF), corn-wheat rotation with recommended fertilization (CWR), green manure-wheat rotation (GWR) and soybean-wheat rotation (BWR). Except for treatment of CWF, fertilizers of rest three treatments were calculated according to the method of soil testing and determining fertilizer recommendations (STDFR). Plants tissues and soil with different depth were sampled for nutrients analysis.【Result】Compared with CWF, with 11.8% reduction of nitrogent and 41.7% reduction of phosphorus, the CWR treatment significantly increased wheat yield, with an average increase of 7.4%, and significantly increased the nitrogen and phosphorus uptake of wheat grain and aboveground shoot, with the increase of 10.1% and 8.9% respectively, and the increase of 9.8% and 6.4% respectively. And CWR treatment decreased the surplus rate of soil N, P and K by 25.1%, 72.3% and 54.4% respectively, and increased the economic benefit by 36%. Among three different rotation, CWR rotation had the highest wheat yield, followed by soybean wheat rotation and green manure wheat rotation. GWR rotation had the lowest surplus ratio of NPK among three treatment with optimal fertilizer application, which was significantly lower than that of CWR and GWR rotation, with the decrease range of 87.3%-92.0%, 41.9%-67.7%, 78.1%-85.3% respectively, and obtained the highest economic return.【Conclusion】Fertilization recommendation by monitoring soil nutrients techniques can not only decrease fertilizer input and production cost, but also increase wheat yield, increase nutrient uptake of wheat grain, reduce surplus rate of nitrogen and phosphorus nutrient balance, and thus improve economic benefits. Compared with corn— wheat rotation, soybean wheat rotation not only reduced the input of chemical fertilizer, significantly reduced the surplus of nitrogen, phosphorus and potassium, but also achieved higher economic benefits. In conclusion, it is recommended that fertilizers application rates should be optimized for corn-wheat rotation in Guanzhong Plain, However, taking into account of economic return and ecological benefit, soybean- wheat rotation is prior choice，for the purpose of decreasing soil nutrients surplus  and enhancing the economic return of farmers.


]]> <![CDATA[Genome-Wide Identification and Expression Analysis of ACA Gene Family in <em>Brassica rapa</em>]]> 】Identification of ACA genes family from Brassica rapa, and  analysis of the commonness and characteristics of family genes, which provided data support for further revealing the evolutionary relationship of ACA family. At the same time, analysis of the expression of BraACAs after self-pollination under abiotic stress, which laid the foundation for further exploring how BraACAs as regulate calcium to perform some biological functions. 【Method】Based on Arabidopsis genome database, the ACA gene family of Brassica rapa was identified by homologous alignment. The molecular weight, theoretical isoelectric point and other physicochemical properties were predicted by online software Expasy. Using MEGA 5.0 software to construct phylogenetic tree. Using online software GSDS 2.0 to draw gene structure map. According to the family gene location information, chromosome mapping was carried out in TBtools. Using McscanX software to carry out the collinearity analysis of ACA family genes in Arabidopsis and Brassica rapa. Using online software PlantCARE to predict and analyze the promoter elements of BraACAs. The protein conserved domains were analyzed by online tools Pfam and MEME. The expression of BraACAs gene in different tissues, abiotic stress and self-pollination were detected by qRT-PCR. 【Result】A total of 18 ACA genes were systematically identified from Brassica rapa, which are distributed on 10 chromosomes. According to the phylogenetic tree, classified into four groups including 3, 4, 4 and 7 members. There are many light, abiotic stress and hormone response elements in the promoter of ACA family genes in Brassica rapa, according to promoter element analysis, which indicates that ACA family genes have potential biological function of resisting stress. According to the analysis of protein domains, most of the ACA gene family proteins in Brassica rapa have four functional domains unique to the ACA family, and 13 of them have N-terminal autoinhibitory domains. The results of qRT-PCR showed that BraACAs were mainly expressed in flowers and pods, and the expression of Bra002762 and Bra035649 genes were up-regulated under chill stress, suggesting that Bra002762 and Bra035649 have potential biological functions in response to chill stress; the expression of Bra031701 gene was up-regulated under salt stress, suggesting that Bra031701 has potential biological functions in response to salt stress. There were significant differences in the expression of Bra003276 and Bra024117 genes between self-pollination and cross-pollination, suggesting that Bra003276 and Bra024117 responded to the self-incompatibility of Brassica rapa. The subcellular localization of these five genes were all located in the plasma membrane to verify their function of balancing ion concentration on the membrane. 【Conclusion】BraACAs protein structures contain four highly conserved domains. The expression of BraACAs is specific in tissues, five ACA family gene members encode proteins located on the cell membrane, of which Bra0002762, Bra035649, Bra031701 were associated with chilling and salt stress response, and Bra003276 and Bra024117 were associated with self-incompatibility reaction.


]]> <![CDATA[Transcriptome and proteome analysis of <i>Bacillus subtilis </i>NCD-2 response to L-proline from cotton root exudates]]> . Previous studies showed that L-proline could improve the biofilm formation ability of Bacillus subtilis NCD-2. Through high-throughput sequencing technology, we explored the regulatory genes related to the biofilm formation and biocontrol potential of strain NCD-2, which laid a foundation for further understanding the molecular interaction between cotton root exudates and the strain.【Method】Transcriptome (RNA-seq) and isotope labeled relative quantitative proteomics (iTRAQ) were analyzed after 24 hours of co-culture with 10 mg·mL-1 L-proline and strain NCD-2, respectively. RT-qPCR was used to verify the expression of some differential genes in different metabolic pathways.【Result】Transcriptome analysis showed that 1 071 DEGs were obtained after L-proline and NCD-2 co-culture, of which 602 genes were up-regulated and 469 genes were down regulated. Go analysis showed that 49, 14 and 30 functional items were significantly enriched in biological processes, cell components and molecular functions, respectively. KEGG pathway is mainly enriched in compound metabolism, flagellum assembly, bacterial motility or chemotaxis. Proteomic analysis showed that total of 211 differentially expressed proteins were detected compared to the control. Hierarchical cluster analysis was carried out to group proteins, among which 118 proteins were up-regulated, which 93 proteins were down-regulated. Go analysis showed that 13 and 8 functional items were significantly enriched in biological process and molecular function, respectively. KEGG pathway is mainly enriched in amino acid metabolism, carbohydrate metabolism, flagellum assembly and ABC transporter. Further transcriptional-proteomics analysis revealed that 112 differentially expressed genes (or proteins), including 38 down-regulated genes (or proteins) and 74 up-regulated genes (or proteins), were detected. Go was enriched in 9 aspects, including nutrient reservoir activity, catalytic activity, cell membrane, localization, cellular lipid metabolic process,  oxidation-reduction process, sigma factor activity, transport activity and spore formation. KEGG pathway is mainly enriched in energy metabolism, ABC transporters, antibiotic biosynthesis, flagellum assembly, motility or chemotaxis and two-component system. 26 differentially expressed genes was verified by RT-qPCR, the results showed that there were some differences in the expression level, but the expression trend was basically consistent with that of RNA-seq and iTRAQ.【Conclusion】The interaction between L-proline in cotton root exudates and Bacillus subtilis NCD-2 was a complex biological process, which depended on multiple genes in different metabolic pathway networks. It was clear that differential expressed genes (or proteins) of the two-component system, antibiotic biosynthesis, energy metabolism, motility or chemotaxis, flagellum assembly and in ABC transporter pathway may play an important role in the interaction between cotton root exudates and Bacillus subtilis. The results lay a foundation for further study on the molecular interaction between L-proline and B. subtilis NCD-2.


]]> <![CDATA[The Effects of Different Configurations on Nitrogen Uptake and Utilization Characteristics of Maize-Peanut Intercropping System in West Liaoning]]> 】 This study clarified the nitrogen absorption and utilization characteristics in maize-peanut intercropping by studying the nitrogen concentration, nitrogen uptake, nodulation of peanut and nitrogen distribution under different configuration, which may provide a basis for regional screening and application of N efficient model of maize-peanut intercropping. 【Method】 A field study with 10 treatments was conducted in National Agricultural Experimental Station for Agricultural Environment in Fuxin in 2015 and 2016, which including four cropping systems, sole maize (M), sole peanut (P), intercropping system of 2 rows maize and 4 rows peanut (M2P4), intercropping system of 4 rows maize and 4 rows peanut (M4P4). Each maize treatment including three maize densities (6, 9 and 12 plants/m2). The characteristics and advantages of nitrogen uptake and utilization in maize-peanut intercropping system with different configurations (row proportion and maize density) were analyzed. 【Result】 Compared with monocropping, the change of N concentration in maize and peanut plants was not significant, the N yield of maize and peanut in intercropping was lower than that in monocropping due to the different proportion of land occupy, and was consistent with intercropping biomass performance. Maize-peanut intercropping significantly increased the system nitrogen uptake (N uptake equivalent ratio NER>1), which was mainly due to the nutrient absorption advantage of maize (pNERm was 0.63~0.80). The NER was increased as the row and density of maize increasing. The nitrogen uptake in M4P4 pattern (NER 1.06~1.22) was significantly higher than that in M2P4 pattern (NER 1.0~1.06). In maize-peanut intercropping system, Maize was more competitive than peanuts (Amp>0), and the competitive ability to absorb nitrogen was also stronger (CRmp>1), M4P4 pattern and maize densification can enhance maize competition for nitrogen, increase the advantage of nitrogen uptake (△NU>0) and the contribution of intercropping nutrients to yield. Intercropping with maize could promote nodule formation of peanut. The number of nodule, weight of nodule per plant and weight per nodule of peanut under M4P4 pattern were higher than those under M2P4 pattern, and medium and low density treatments were better for nodulation. The soil available nitrogen content (Nmin) in the intercropping system was higher in the peanut strip than in the maize strip, and the Nmin in the sole peanut strip was higher than that in the intercropped peanut strip, while the Nmin in the sole maize strip was lower than that in the intercropped maize strip. 【Conclusion】 Maize-peanut intercropping could significantly improve the nitrogen uptake and utilization in the system, and maize contributed more to the system nitrogen uptake. Moderate increase of maize row ratio and density was beneficial to increase the nitrogen uptake equivalent ratio, enhance maize competition for nitrogen nutrition, and the contribution of intercropping nutrients to yield. In this study, M4P4-6 and M4P4-8 were the better pattern for maize-peanut intercropping, and the contribution rate of nitrogen uptake and utilization to the yield of the system could reach 18%. The promotion of maize/peanut intercropping on dry matter and peanut biological nitrogen fixation, as well as the competitive ability of maize to absorb nitrogen, were the important reasons for the advantages of maize/peanut intercropping in nitrogen utilization.]]> <![CDATA[Effect of Drip Fertigation Mode on Maize Yield, Nutrient Uptake and Economic Benefit in Semi-Arid Area of Jilin Province]]> <![CDATA[Critical Nitrogen Dilution Curve and Nitrogen Nutrition Diagnosis of Summer Maize Under Different Application of Nitrogen and Phosphorus Rate]]> different nitrogen and phosphorus application rate on summer maize aboveground biomass, nitrogen accumulation, and drew a critical nitrogen concentration dilution curve. The nitrogen status of maize plant was diagnosed and evaluated based on a model of nitrogen nutrition index (NNI) under different nitrogen and phosphorus interaction conditions, which provide a theoretical basis for the rational application of nitrogen and phosphorus fertilizers in summer maize in Guanzhong Plain, Shaanxi.【Method】 Field experiments design using Zhengdan958 (ZD958) and Yuyu22 (YY22) as tested materials was four phosphorus application rates and five nitrogen application rates, including 0(P0), 60(P1), 120(P2), 180(P3) kg P2O5·hm-2 and 0(N0), 75(N1), 150(N2), 225(N3), 300(N4) kg N·hm-2 during 2019-2020. The aboveground samples were taken during the jointing, tasseling, filling, and maturity stages of summer maize to analyze the effects of nitrogen and phosphorus application rate on maize dry matter accumulation, dynamic changes of nitrogen concentration and grain yield. The field test data was used to construct and verify the critical nitrogen dilution curve model of summer maize.【Result】The results showed that nitrogen and phosphorus application rate significantly increased aboveground biomass, plant nitrogen concentrations and grain yield of summer maize. The grain yield and aboveground biomass of summer maize increased as the nitrogen application rate increased within the same phosphorus application conditions. The nitrogen concentration of maize plants showed a decreasing trend with the extension of growth period and the increase of aboveground dry matter weight. There is a power exponential relationship between nitrogen concentration and aboveground biomass. In addition, phosphorus application could promote maize plant nitrogen absorption and aboveground dry matter accumulation. The overall performance of the phosphorus application treatments was P2>P3≈P1>P0 under the same nitrogen application conditions, appropriate phosphorus application could improve the capacity of maize plant for nitrogen absorption and relieved the decline of nitrogen concentration. The critical nitrogen concentration curves of maize were constructed according to the aboveground dry matter weight and its nitrogen concentration under different phosphorus application conditions, (P0, Nc=27.98DM-0.249; P1, Nc=29.77DM-0.182; P2, Nc= 30.81DM-0.138; P3, Nc=30.06DM-0.187). The relatively stable model had a linear correlation between the fitted and actual plant nitrogen concentrations, which shown that the n-RMSE were 10.23%、6.67%、6.95% and 7.19%. The NNI values were calculated based on the critical nitrogen concentration curves. NNI increased with the increase of nitrogen application in each growth stages within the same phosphorus application conditions. NNI was also positively correlated with relative aboveground biomass (RDW) and relative yield (RY). 【Conclusion】Based on the model of nitrogen nutrition(NNI) in this study, N2-N3 and P1-P2 are the best conditions，and the fitting curve of comprehensive nitrogen application rate and grain yield, the nitrogen rate of 187.5-205.7 kg·hm-2 and phosphorus rate of 60-120 kg·hm-2 was the optimal fertilization option for summer maize in Guanzhong Plain, Shaanxi.]]> <![CDATA[Response of Nematode Community to Soil Disturbance Under Long-term No-tillage Practice in the Black Soil of Northeast China]]> <![CDATA[Effects of CaSR and CCK-1R mediated soybean protein hydrolysate on appetite using mouse as a model]]> and mechanisms of soy protein hydrolysate (SPH) on the appetite in mice and provide new frame work guidelines for strategies towards manipulating feed intake in pigs.【Method】In this study, pepsin was used to hydrolyze soy protein to produce SPH. Firstly, the effects on short-term feed intake and the expressions of duodenal peptide sensing receptors calcium sensing receptor (CaSR), G protein-coupled receptor 93 (GPR9)3 and oligopeptide transporter 1 (PepT1) were investigated by intragastrically different concentrations of SPH. Based on this, the CaSR inhibitor NPS2143 and the peripheral cholecystokinin-1 receptor (CCK-1R) inhibitor Devazepide were intraperitoneally injected , respectively, to investigate whether SPH inhibited feed intake by the CASR-CCK-CCK-1R-hypothalamus pathway.【Result】The amount of 1.5g·kg-1 SPH reduced the 0-1h feed intake (P<0.05), and increased the CaSR expression (P<0.05). Compared with SPH group, the feed intake of SPH + NPS2143 group were increased at 0-1h, and the plasma CCK levels were decreased, and there were no differences from the control group (0.05) (P<0.05), while the effects disappeared in SPH+Devazepide group. However, SPH had no effect on the small intestine transit rate or the expression of the hypothalamic food-promoting factors neuropeptide Y (NPY) and agoutirelated peptide (AgRP).【Conclusion】CaSR mediates SPH to promote CCK secretion, and through the peripheral CCK-1 receptor to delay gastric emptying rate and improve the expression of hypothalamic anorexia nerve factor POMC to suppress appetite.


]]> <![CDATA[Comparison Analysis on Volatile Compound and Related Gene Expression in ‘Yali’ Pear during Cellar and Cold Storage]]> <![CDATA[Adhesin Gene mad2 Knockout and Functional Effects on Characteristics of Growth, Virulence, Adhesion and Inducing Plant Responses in <em>Metarhizium anisopliae</em>]]> Metarhizium anisopliae, an entomopathogenic fungus, is found also an endophyte. It was known that MAD2 was one of the two adhesin proteins of M. anisopliae, which play a vital role in adhere and colonize in plants, but its functional mechanism understood little. In this study, we will explore the functional effect of MAD2 protein on the characteristics of growth, virulence, adhesion and inducing plant responses in M. anisopliae by construction of the mad2 mutant strain (Δmad2) of M. anisopliae strain Ma9. 【Method】The genomic DNA sequences of mad2 anteroposterior were obtained from NCBI, and specific primers were designed to amplify mad2 homologous arm genes S1 and S2 by PCR based on genomic DNA template of M. anisopliae strain Ma9. Meanwhile, Hyg-F/R primer pair was designed to amplify hygromycin gene with promoter sequence based on pKH-KO vector DNA template. Then, homologous knockout boxes S1H and S2H of mad2 were constructed by Overlap PCR. Finally, mad2 knockout strains with stable inheritance were obtained by PEG-mediated protoplast transformation of the homologous knockout boxes. By comparing the biological characteristics of the knockout strains (Δmad2) to the wild strains (WT), the effect of MAD2 protein on the characteristics of M. anisopliae growth, virulence, adhesion and inducing the peanut response of symbiosis genes were analyzed.【Result】The result showed that the spore germination rate of mutant strain was significantly decreased and spore semi-germination time was significantly prolonged 5.47 h compare to wild strain (WT), as well as the hypha length of Δmad2 was significantly shorter than WT in 12 h and 14 h incubation, occupied 22.2% and 23.7% respectively. The sporulation in 12-day incubation was reduced by 33.33% compared to WT. The ability of Δmad2 strain adhesion in onion was significantly decreased but showed no differences in adhere to the hind wings of locust. In addition, knockout mad2 did not affect the virulence of M. anisopliae to silkworm. After 12 h inoculating mad2 knockout strain in peanut, the transcription level of peanut symbiosis receptor gene SYMRK, Calcium signal decoding related genes (CAM, CCaMK, DELLA)，lipid and nitrogen transfer related genes (LTP1, NRT24, ABCC2) were significantly regulated down compared to the treatment of wild strain. While compared with blank control, Δmad2 still had certain up-regulation of SYMRK, significantly inhibited the transcription levels of CAM, CCAMK and DELLA, but had no effect on the transcription level of ABCC2, LTP1 and NRT24.【Conclusion】In conclusion, M. anisopliae adhesin protein MAD2 affect spore germination, initial growth of hypha, sporulation quantity and plants adhesion, while had no effect on insect adhesion and virulence of strain, and MAD2 was induced the transcription level of symbiosis genes in the initial stage of interaction.]]> <![CDATA[Auxin Involved in the Process of Petal Abscission of Tree Peony 'Luoyanghong' Cut Flowers by Ethylene Promoting]]> -1 ethylene antagonist Correxian (AVB) , 20 μL·L-1 ethylene releasing agent ethephon (CEPA) or 20 μL·L-1 Correxian for 1 h, respectively, followed by 20 μL·L-1 ethephon 1 h (AVB+CEPA). The flowers were then placed in individual vases filled with distilled water. The morphology of the petals absciss zone cells were observed by using a microscope. The petal anti-falling ability were determined by using the tensile test during the vase cutting process.The physiological effects of different pre-treatments were observed respectively using the physiological and biochemical methods to determine the ethylene and auxin metabolism, the absciss zone hydrolysis-related enzyme activities and the relative expressions of PsETR1, PsCTR1, PsEIN3, PsERF1, PsYUCCA10, PsPIN1, PsPME1, PsPG1 and PsBG1 genes. 【Result】The results showed that the basal petal of the cut tree peony 'Luoyanghong' had a clear separation layer structure. AVB significantly delayed the occurrence of ethylene climacteric in cut flowers, and decreased the ethylene release peak by 34.9% (P<0.05), while the petal anti-falling ability was improved. The activities of polygalaturonase (PG), β-glucosidase (BG) and the expressions of PsPG1 and PsBG1 genes at the base of the petals absciss zone were reduced, which delayed the senescence process of cut tree peony flowers, thus significantly extended its vase life. Nevertheless, the exogenous CEPA significantly accelerated the release rate of endogenous ethylene in the petals, increased the activities of IAA oxidase (IAAO), PG and BG, and accelerated the senescence of the absciss zone cells in the petals of cut flowers, reduced the petal anti-falling ability thus promoted its wilting and falling. Meanwhile, the vase life and the optimal viewing period of AVB+CEPA composite pretreatment were not much different from those control, and so CEPA could partially offset the physiological effects of AVB. 【Conclusion】For the ethylene sensitive cut tree peony 'Luoyanghong', endogenous auxin is involved in the process of ethylene promoting the abscission of petal absciss zone cells. The control of ethylene is the basic way to improve the quality of cut flowers ‘Luoyanghong’.]]> <![CDATA[p-coumaric acid promoted wound healing of potato tubers by accelerating the deposition of suberin poly phenolic and lignin at wound sites]]> -1 p-CA for 10 min and stored at room temperature and protected from light for healing. The weight loss and the disease index of wounded tubers inoculated with Fusarium sulphureum were determined, the deposition of suberin polyphenolic and lignin at wounded sites were observed, the activity of the key enzymes of phenylpropane metabolism and peroxidase as well as the content of phenylpropane metabolism products and H2O2 at wounded sites were measured.【Result】The weight loss and the disease index of wounded tubers were significantly reduced by p-CA treatment, and were 38.46% and 43.18% lower than those of control on the 14 day of healing, respectively. p-CA treatment accelerated the deposition of suberin polyphenolic and lignin at wound sites of potato tubers, and the thickness of cell layers in treated tubers were 26.43% and 30.26% higher than the control on the 14 day of healing, respectively. p-CA treatment also significantly increased the activities of phenylalanine ammonia lyase, cinnamic acid-4-hydroxylase, 4-coumaryl coenzyme A ligase and cinnamyl alcohol dehydrogenase at wounde sites of tubers, with the enzyme activities of the treated tubers being 32.17%, 23.51%, 25.09% and 23.08% higher than the control on 7 day, respectively. p-CA treatment also promoted the synthesis of cinnamic acid, p-coumaric acid, caffeic acid, ferulic acid, sinapic acid and total phenolics, with the contents of cinnamic acid, p-coumaric acid, caffeic acid and total phenolics in the treated tubers on 14 day being 34.26%, 38.29%, 19.31% and 41.04% higher than the control respectively, and the contents of ferulic acid, sinapic acid in the treated tubers being 38.33% and 20.47% higher than the control on 21 day, respectively. In addition, p-CA treatment promoted the accumulation of cinnamyl alcohol, coniferyl alcohol, sinapis alcohol and lignin at wound sites, with the contents of cinnamyl alcohol and lignin in the treated tubers being 36.93% and 31.66% higher than the control on 14 day, respectively, and the contents of coniferyl alcohol and sinapis alcohol in the treated tubers were 41.43% and 34.05% higher than the control on 21 day, respectively. The p-CA treatment also increased the H2O2 content and peroxidase activity at the wound sites, with the H2O2 content and peroxidase activity of the treated tubers being 40.25% and 27.01% higher than the control on 7 day, respectively.【Conclusion】The p-CA treatment accelerated wound healing of potato tubers by activating phenylpropanoid metabolism, increasing H2O2 content and peroxidase activity, and promoting the accumulation of suberin polyphenolic and lignin in potato tuber wound sites. ]]> <![CDATA[Cloning and Function Analysis of MsMAX2 gene in alfalfa (<em>Medicago sativa</em> L.)]]> Medicago sativa L.) breeding. Exploring and functional characterization of key branching-related genes are of significance in accelerating breeding of alfalfa with high yield and quality. MAX2 is an important branching-related gene, which is involved in the regulation of branching in several plant species. 【Objective】Our research on the functional characterization of MsMAX2 in alfalfa will lay a foundation for the molecular mechanism of MsMAX2 in regulating branch development in alfalfa.【Method】The gene sequence of MAX2 in alfalfa was isolated by using homologous cloning. Sequence characteristics and phylogenetic tree of MsMAX2 were analyzed by using bioinformatics tools including Expy Protparatam, DNAMAN, and MEGA-X. The real-time quantitative PCR (qRT-PCR) was applied to detect the tissue-specific expression pattern of MsMAX2 in alfalfa. The subcellular localization of the MsMAX2 protein was determined by using transient expression system in tobacco. The biological function of MsMAX2 was clarified by transformation in the Arabidopsis mutant via Agrobacterium-mediated transformation. Proteins interacting with MsMAX2 were determined by using yeast two-hybrid assay. 【Result】The length of MsMAX2 CDS is 2136 bp, encoding a protein of 711 amino acids, and it belongs to the F-box protein super-family. Phylogenetic analysis showed that the evolution of MAX2 homologs was highly similar to the differentiation of species, indicating that MsMAX2 was a functionally conserved gene. It was showed that MsMAX2 was expressed in the neck at the highest level, followed by in the leaves of seedling, the inflorescences on pollination day and the roots; the expression level of MsMAX2 was relatively low in other tissues, indicating it functions in multiple tissues. Subcellular localization assay showed that the MsMAX2 protein was localized in the nucleus. Complementation assay in Arabidopsis max2 mutant showed that the multi-branch phenotype was recovered by the ectopic expression of MsMAX2. Yeast two hybrid assay demonstrated that the interaction between MsMAX2 and hormone receptor D14 depended on the existence of strigolactones. 【Conclusion】 The MsMAX2 was obtained from alfalfa and it was highly expressed in the neck and the encoding MsMAX2 protein was localized in nucleus. When the MsMAX2 was over-expressed in the Arabidopsis max2 mutant, its multi-branch phenotype was recovered, indicating that MsMAX2 regulates branch development in alfalfa plant, and its function was conserved.]]> <![CDATA[Generation of ospin9 Mutants in Rice by CRISPR/Cas9 Genome Editing Technology]]> <![CDATA[Genome-Wide Association Study of Grain Quality Related Characteristics of Spring Wheat]]> <![CDATA[Creation of new maize variety with fragrant rice like flavor by editing BADH2-1 and BADH2-2 using CRISPR/Cas9]]> -1, respectively. On the contrary, no 2-AP was detected in JING724 wild type. 【Conclusion】With site specific mutations introduced into ZmBADH2-1 and ZmBADH2-2 simultaneously using CRISPR/Cas9, new maize variety with fragrant rice like flavor was created successfully.]]> <![CDATA[Gene Cloning and Functional Analysis of Yellow Green Leaf Mutant ygl3 in Rice]]> <![CDATA[Cloning of TaBG and analysis of its function in anther dehiscence in wheat]]> <![CDATA[Characteristics of Efficient Nitrogen Uptake and Transport of Rapeseed (<em>Brassica napus</em> L.) at Seedling Stage]]> -1) and N starvation (0.475 mmol·L-1) at three different growth stages (Phenological growth stages 12, 14 and 16) in hydroponic culture. At the same time, the 15N isotope tracer technique was applied to study the uptake and transport capacity of NO3? and NH4+. Additionally, the expression level of genes (BnNPFs, BnNRT2s and BnAMTs）related to N uptake and transport in rapeseed germplasms with contrasting N efficiency were further analyzed by real-time quantitative PCR (qRT-PCR).【Result】Rapeseed germplasm ‘498’ showed superior advantages in plant growth and root development under different N concentrations, and the root morphological indexes (main root length, total root length, root surface area, root volume and lateral root number), biomass, N accumulation and N uptake efficiency were all significantly greater than those of germplasm ‘428’. 15N isotope tracer test also showed that ‘498’ showed greater advantage in the uptake and accumulation of NO3- and NH4+, especially for NH4+, as indicated by the significant differences in the accumulation of 15NH4+ between two germplasms. qRT-PCR analysis further found that under normal N conditions, the relative expressions of BnNPF6.3a, BnNRT2.1e, BnNPF7.2a, BnNPF7.2c, BnNPF6.2c, BnAMT1;2a, BnAMT1;3c, BnAMT1;4a, BnAMT2;1a and BnAMT2;1b (involved in the uptake and transport of NO3- and NH4+) was Significantly higher in ‘498’ than that in ‘428’. While under N starvation stress, the relative expressions of BnNRT2.4a、BnNRT2.5a and BnNRT2.5b (involved in NO3- uptake and transport) was significantly lower in the root of ‘498’ than that of ‘428’, but the expression level of BnNPF7.3a and BnNPF6.2c (referred to NO3- transport and redistribution) was significantly higher in ‘498’ than that in ‘428’, as well as the expression level of BnAMT1;1a、BnAMT1;2a、BnAMT1;3c、BnAMT1;4a、BnAMT2;1a and BnAMT2;1b (involved in NH4+ uptake and transport).【Conclusion】Compared with N-inefficient germplasm ‘428’, N-efficient germplasm ‘498’ were superior in root length, root surface (volume) and lateral root number, additionally with greater ability in N (especially NH4+) uptake and accumulation. Under normal N conditions, the expression of genes involved in NO3- and NH4+ absorption and transport were relatively higher in ‘498’, while the relative expression of genes involved in the NO3- transport and redistribution as well as NH4+ absorption and transport were significantly higher in ‘498’ than that in ‘428’ under N deficiency stress, illustrating the relative higher N uptake efficiency of ‘498’ possibly link to the higher expressions of several BnNPFs sand BnAMTs.]]> <![CDATA[Effects and Mechanism of Humic Acid in Humic Acid Enhanced Phosphate Fertilizer on Fertilizer-Phosphorus Migration]]> 2+ and phosphate adsorption characteristics was systematacially compared to provide the theoretical basis for the study on high-efficiency mechanism of humic acid enhanced phosphate fertilizer.【Method】In this study, HA, HAP, and conventional phosphate fertilizer were prepared in the laboratory, and PHA was extracted by adjusting the pH of HAP’s solution based on the method of alkali-extraction acid-precipitation. Effects of HA and PHA applicated with phosphate fertilizer on the migration of fertilizer-phosphorus in soil was investigated. The addition of HA or PHA accounted for 0.5% and 5% of the application amount of phosphate fertilizer, and marked with 0.5HA+P, 0.5PHA+P, 5HA+P, and 5PHA+P, respectively. Only phosphate fertilizer application (P) and no fertilizer application (CK) were arranged at the same time. In addition, the adsorption characteristics of HA or PHA on Ca2+ and phosphate were studied to reveal the mechanism that HA and PHA showed different performance on phosphorus migration. 【Result】Both HA and PHA could promote the migration of fertilizer-phosphorus. Phosphorus could migrate to 42 mm vertical distance from the fertilizer layer under the treatment of P, while it could reach 46 mm and 50 mm away from the fertilizer layer, respectively, when phosphate fertilizers application combined with HA and PHA. This result resulted from the fact that HA or PHA had a higher adsorption capacity on soil Ca2+, and the application of HA or PHA reduced phosphorus fixation. The cumulative percentage of soil available P in total P application tended to be stable after 42 mm away from the fertilizer layer, and 0.5 HA+P ≈ 5PHA+P > 5HA+P > 0.5PHA + P > P. The promotion effect of PHA on fertilizer-phosphorus migration would be enhanced with the addition of PHA increase, while HA was the opposite. Which might be related to the stronger mobility and the weaker phosphate adsorption of PHA than that of HA. The adsorption of Ca2+ by HA and PHA was the result of membrane diffusion and intra-particle diffusion. However, the difficulty of Ca2+ diffusion to the surface of PHA particles was lower than that of HA, and the difficulty of Ca2+ diffusion in the interior of PHA particles was higher than that of HA. Langmuir isothermal adsorption model could well fit the isothermal adsorption curves of HA or PHA on Ca2+, and the theoretical maximum adsorption capacity of HA on Ca2+ was higher than that of PHA, but the adsorption of PHA on Ca2+ was mainly chemical adsorption.【Conclusion】Both raw humic acid (HA) and humic acid extracted from humic acid enhanced phosphate fertilizers (PHA) have certain ability to adsorb Ca2+, so they can promote the migration of fertilizer-phosphorus in the soil. However, the migration distance of fertilizer-phosphorus of PHA was longer than that of HA, when phosphate application was combined with HA or PHA. This may be one reason why PHA can improve the use efficiency of phosphate fertilizer.]]> <![CDATA[Phosphorus Fertilizer Replacement Value of Livestock Manure in Winter Wheat]]> <![CDATA[Cloning, Expression and Anti-Virus Function Analysis of <em>Solanum lycopersicum</em> SlN-like]]> Solanum lycopersicum is an important vegetable crop, and its growth is persecuted by various biological factors including pests, fungi, bacteria and viruses. Clarifying the antiviral function and mechanism of the S. lycopersicum resistance gene SlN-like provides a theoretical basis for the genetic breeding of antiviral tomatoes and the targeted development of the antiviral agents.【Method】The full length of S. lycopersicum SlN-like was obtained from the Solanaceae Genomics Network database and was divided into 4 segments, fusion PCR was used to amplify it; bioinformatics was used to analysis the evolutionary relationship, protein characteristics, conserved domains, subcellular location and interaction relationship of SlN-like; real-time fluorescent quantitative PCR was used to analysis the SlN-like expression in tomato roots, stems, leaves, flowers and fruits and its response after tobacco mosaic virus (TMV) infection; silencing tomato endogenous SlN-like using tobacco rattle virus (TRV)-mediated gene silencing technology, and the silent plants were inoculated with TMV-GFP to clarify the influence of SlN-like on virus infection. The expressions of abscisic acid (ABA), jasmonic acid (JA) and ethylene (ET) hormone-related genes in silenced plants, and the expression of SlN-like after application of ethephon for 3, 6, 12 and 24 h were analyzed by real-time fluorescence quantitative PCR to investigate the mechanism of tomato SlN-like regulatory hormone pathway in response to virus infection.【Result】Through molecular cloning and fusion PCR technology, a 3 444 bp tomato SlN-like gene was cloned from S. lycopersicum variety Micro-Tom, and uploaded to NCBI to obtain the sequence number MW792493. Through bioinformatics analysis, it was found that SlN-like contains TIR, NB-ARC and NACHT domains, and is closely related to Solanum tuberosum N-like (AAP44394.1). SlN-like expresses in all tissues of tomato, with the highest expression in stems, followed by roots, flowers, leaves and fruits. After TMV-GFP infection tomato at 5 and 7 day, the SlN-like expression was higher than that of PBS treatment, and TMV-GFP infection would cause the expression of SlN-like to increase continuously. TRV vector induced silencing of SlN-like genes in tomato, and found that silencing 87.3% of SlN-like did not affect tomato growth phenotype, but silencing SlN-like promoted the infection of TMV-GFP; real-time fluorescent quantitative PCR analysis found that the expression of ERF1 in SlN-like-silent plants was significantly reduced, only 12.5% of the control group; the expression of SlN-like increased after 3 h of external application of ethephon, and reached the highest peak at 12 h, which was 2.71 times that of the control group, and returned to normal at 24 h. 【Conclusion】S. lycopersicum SlN-like belongs to the NBS-LRR disease-resistant protein family, which contain TIR, NB-ARC and NACHT conserved domains, and expresses in all organs of tomato. The expression of SlN-like is induced by TMV-GFP infection. Silencing SlN-like can promote TMV-GFP infection, revealing that SlN-like acts as a positive regulator to inhibit virus infection. Silencing SlN-like reduced the expression of ET-related gene ERF1, while external application of ethephon resulted in the differential expression of SlN-like, revealing that S. lycopersicum SlN-like participates in tomato antiviral defense through the ethylene pathway.]]> <![CDATA[Cloning of <em>Nicotiana Benthamiana</em><em>NAC062</em> and Its Inhibitory Effect on Potato Virus Y Infection]]> <![CDATA[Analysis of resistance mechanism of CiNPR4 transgenic plants to citrus canker]]> <![CDATA[]]> <![CDATA[]]> <![CDATA[]]> <![CDATA[]]> <![CDATA[]]> <![CDATA[]]> <![CDATA[]]> <![CDATA[]]> <![CDATA[]]> <![CDATA[]]>