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  • TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY
    TIANLongBing, SHENZhaoYin, ZHAOXiaoTian, ZHANGFang, HOUWenFeng, GAOQiang, WANGYin
    Scientia Agricultura Sinica. 2024, 57(21): 4221-4237. https://doi.org/10.3864/j.issn.0578-1752.2024.21.005

    【Objective】Reasonably increasing planting density combined with appropriate nitrogen (N) application rate is an important technical approach for increasing maize yield and resource use efficiency. Understanding the interactive effects of planting density and N rate on maize growth, evapotranspiration (ET) and water use efficiency (WUE) during the growing season, could provide a basis for improving its use efficiency when increasing planting density and controlling N input in maize production. 【Method】Field experiments were conducted during 2022 to 2023 in Jilin Province. Two maize cultivars, Liangyu 99 (LY99) and Demeiya 3 (DMY3), were used in this study. Three planting densities of 50 000, 70 000 and 90 000 plants/hm2 and four N application rates of 0, 100, 200 and 300 kg N·hm-2 were designed to investigate the effects of planting density and N application rate on grain yield and water productivity of different maize cultivars, as well as the dry matter (DM), soil water content, ET and WUE at various growth stages. 【Result】Planting density significantly affected DM and grain yield of maize, but the response trends varied between cultivars. Grain yields of LY99 with 70 000 plants/hm2 was 11.1% and 18.3% higher than that with 50 000 and 90 000 plants/hm2, respectively. The average yield of DMY3 planted with 70 000 plants/hm2 and 90 000 plants/hm2 was 10.5% and 9.3% higher than that of 50 000 plants/hm2, respectively. Nitrogen fertilization significantly increased DM and grain yield of maize, and also showed significant interactive effects with cultivar or planting density. Compared with N0, grain yields of LY99 were increased by 38.0% to 60.7% under N1, and the yield increases for DMY3 were 24.4% to 38.2%. Notably, the yield responses to N rates were more pronounced for LY99 compared with DMY3. For both cultivars, the yield differences between low N rate and high N rate enlarged with increasing planting density, with LY99 showing a more distinct performance. The water consumption and utilization of maize plants were also significantly affected by planting density, N rate and their interaction. During the growing season, the total ET of DMY3 continually increased with increasing density, while that of LY99 showed the highest values with 70 000 plants/hm2 among different densities. In each density condition, the ET of both cultivars increased with increasing N application rates. The WUE of maize plants showed complex responses to planting density and N rate at different growth stages, due to the varied annual precipitation and distribution patterns. The average increase of water productivity of LY99 under planting 50 000 and 70 000 plants/hm2 was 8.6% and 10.4% compared with 90 000 plants/hm2 respectively. DMY3 had the highest water productivity when planting 70 000 plants/hm2, which increased by 5.8% and 5.3% compared with 50 000 and 90 000 plants/hm2, respectively. The water productivity showed different responses to N rate among the three densities. In general, the difference of nitrogen application under low density was small, but it increased significantly under medium and high density. Compared wtih DMY3, LY99 showed higher increases for water productivity when N fertilizer was applied under medium and high density conditions. The correlation analysis showed that interactive effects of planting density and N rate significantly affected maize yield and water productivity by influencing the water utilization at various growth stages. 【Conclusion】Planting density and N rate had significant interactive effects on maize yield and water utilization in the rain-fed region of Northeast China. The two maize cultivars used in this study could obtain high grain yield and water productivity under a moderately higher density of 70 000 plants/hm2 combined with 200 kg N·hm-2 rate.

  • SOIL & FERTILIZER·WATER-SAVING IRRIGATION·AGROECOLOGY & ENVIRONMENT
    TIANYun, WANGXiaoRui, YINMinHao, ZHANGHuiJie
    Scientia Agricultura Sinica. 2024, 57(22): 4507-4521. https://doi.org/10.3864/j.issn.0578-1752.2024.22.010

    【Objective】Based on the current “dual carbon” strategic goal, this study aimed to clarify the current characteristics, spatio-temporal pattern and influencing factors of agricultural net carbon sink, so as to provide the important support for accelerating agricultural sink increase and emission reduction.【Method】Based on the scientific reconstruction of the index system, the carbon sink/carbon emission factor method was used to measure and analyze the current situation of China’s agricultural net carbon sink. Then the spatial autocorrelation model was used to discuss the spatial dependence and spatial heterogeneity. Finally, the least-squares method was used to analyze the main factors affecting the change of its intensity. 【Result】From 2005 to 2022, the total amount of agricultural net carbon sink in China was in an obvious upward trend, although there were some interannual fluctuations, and its evolutionary characteristics could be roughly divided into four stages, namely, “continuous rise”, “fluctuating decline”, “rapid rise”, and “slow rise”; the intensity of agricultural net carbon sink was also in an obvious upward trend, with only a slight difference in the trajectory of the evolution, and the difference in its growth rate could be roughly categorized into four stages: “continuous rapid growth”, “slow growth”, “fluctuating ups and downs”, and “slow growth”. 2022, the amount of agricultural net carbon sink had a large interprovincial difference, with Inner Mongolia being the first and Shanghai being the last, and compared with the year of 2005, all the provinces had a significant increase. In 2022, the net carbon sink intensity of agriculture would be the highest in Henan and the lowest in Qinghai, with all provinces showing different degrees of increase compared with 2005. China’s provincial agricultural net carbon sink intensity as a whole showed obvious spatial dependence, but there was also a local spatial clustering phenomenon, more than 70% of the provinces showed obvious spatial clustering characteristics, and the number of provinces located in the high-high clustering and the low-low clustering was approaching. The structure of arable land use, urbanization level, rural residents' income level and the internal industrial structure of agriculture all had a significant impact on the intensity of agricultural net carbon sink; specifically, the higher the ratio of sown area of grain crops, or the higher the urbanization rate, or the higher the income level of rural residents, or the larger the ratio of plantation industry to animal husbandry, the higher the intensity of net carbon sink in agriculture.【Conclusion】The total amount and intensity of China’s agricultural net carbon sink were in a fluctuating upward trend and there were obvious inter-provincial differences. The intensity of China’s agricultural net carbon sink showed obvious spatial dependence and spatial heterogeneity. The intensity of the agricultural net carbon sink was affected by the structure of arable land use, the level of urbanization, the level of rural residents' income, and the structure of the internal industries of agriculture. The measures should be taken to promote the enhancement of sink and emission reductions and to promote the enhancement of agricultural net carbon sink in agriculture, such as establishing a sound policy support system for the development of low-carbon agriculture, strengthening inter-provincial exchanges and cooperation, and increasing financial support for agriculture.

  • SPECIAL FOCUS: MINING AND UTILIZATION OF CROP DISEASE RESISTANCE AND INSECT-RELATED GENES
    HE NiQing, LIN ShaoJun, CHENG ZhaoPing, YANG DeWei
    Scientia Agricultura Sinica. 2024, 57(23): 4589-4592. https://doi.org/10.3864/j.issn.0578-1752.2024.23.001
  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    LÜShuWei, TANGXuan, LIChen
    Scientia Agricultura Sinica. 2025, 58(1): 1-9. https://doi.org/10.3864/j.issn.0578-1752.2025.01.001

    Seed shattering is a major factor limiting rice production, and breeding new rice varieties with moderate seed shattering is a key challenge faced by rice breeders worldwide. Rice is the most important cereal crop in China, plays a vital role for national food security. Seed shattering is one of the most important traits during rice domestication, and the abscission zone is the important region to control seed shattering. Compared with wild rice, cultivar has eliminated the seed shattering with partially developed abscission layer. Seed shattering not only has a direct impact on the yield, but also affects the way of its mechanical harvest. In order to breed rice varieties with moderate seed shattering in agricultural production, it is necessary to mine and utilize important seed shattering genes and introduce them into excellent rice varieties for genetic improvement, so as to breed new rice varieties suitable for mechanical harvesting with moderate seed shattering. Several seed shattering genes had been identified by map-based cloning, such as SH4/SHA1, qSH1, OsSh1/ObSH3, and their functional mechanisms had been analyzed. At the same time, new rice materials with moderate seed shattering have been successfully developed through CRISPR/Cas9 gene editing technology, gamma ray mutagenesis technology and gene introduction methods. Seed shattering has an important effect on grain yield and rice harvesting methods, in this paper, we reviewed the methods, physiologic basis, the identification of seed shattering genes and genetic mechanism of seed shattering in rice. At the same time, it is proposed that by using the important genes in excellent rice germplasm resources, could provide reference for exploring the mechanism of rice seed shattering, and breed new rice varieties suitable for mechanical harvesting with moderate seed shattering.

  • TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY
    LIAOPing, WENGWenAn, GAOHui, ZHANGHongCheng
    Scientia Agricultura Sinica. 2024, 57(24): 4854-4870. https://doi.org/10.3864/j.issn.0578-1752.2024.24.003

    With the continuous improvement in rice cultivation techniques, China has maintained a high rice production level of about 210 million tons over the past decade. Direct-seeding rice cultivation technology, recognized for its efficiency and simplicity, has been favored by Chinese farmers. However, controversies persist regarding direct-seeding rice compared to transplanted rice in national-scale production. Thus, this study employed meta-analysis techniques to quantify disparities in grain yield, economic benefit, rice quality, lodging characteristic, and greenhouse gas emissions between direct-seeding rice and transplanted rice. Our results indicated that direct-seeding rice significantly reduced grain yield by an average of 6.3% relative to transplanted rice, which was main due to the reduced total spikelet (-3.8%) and filled-grain percentage (-1.8%). In different planting systems in China, the yield of direct-seeding rice had significantly decreased compared to transplanted rice, and the direct-seeding rice-induced reductions in yield of single rice (-10.9%) and late rice (-13.1%) were higher than those of middle rice (-4.8%) and early rice (-4.4%). The grain yield reductions for direct-seeding rice were from 10% to 20% in Jilin, Liaoning, Xinjiang, Ningxia, Shandong, Jiangsu, and Zhejiang provinces, meanwhile Heilongjiang and Jiangxi provinces saw reductions of 5% to 10%, but it had no significant effect in other provinces. Direct-seeding rice resulted in comparable net economic return relative to transplanted rice (p> 0.05). Direct-seeding rice reduced milled rice rate (-3.1%) and gel consistency (-3.5%), improved appearance quality (chalkiness percentage and chalkiness degree, which decreased by 25.3% and 22.5%, respectively), whereas no significant effects were observed on nutrition quality and taste value. Direct-seeding rice increased lodging index at base of the first (+12.4%) and third (+10.3%) internodes, but not at the second internode, indicating an increase in risk of lodging relative to transplanted rice. In terms of greenhouse gas emissions, direct-seeding rice fields showed reductions in methane emissions (-42.8%), global warming potential (-36.2%), and greenhouse gas intensity (-41.1%) compared to transplanted rice fields, while promoting nitrous oxide emissions (+29.1%). In addition, a review was recounted on nitrogen utilization and its loss, water and energy use efficiency, and weed incidence. Finally, the recommendations for the future advancement of direct-seeding rice were proposed, main focusing on rice variety breeding, rice cultivation technique optimization, rice planting area layout, as well as policies and services with the goal of technological innovation and regionalized application of direct-seeding rice cultivation technology in China.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    LIU YiHan, MU QingShan, HE Xiang, CHEN Min, HU Jin, GUAN YaJing
    Scientia Agricultura Sinica. 2024, 57(21): 4161-4174. https://doi.org/10.3864/j.issn.0578-1752.2024.21.001

    【Objective】FWL (Fruit Weight2.2-Like) gene is a negative regulator of cell proliferation, which not only regulates plant organogenesis and organ size, but also participates in the regulation of metal ion transport accumulation and signal transduction. Analyzing of the function of OsFWL3 gene is helpful to reveal the transport mechanism of trace metal elements in crops. It provides theoretical support for reducing heavy metal accumulation and improving crop quality. 【Method】The gene information, genome structure and phylogenetic tree of OsFWLs family were analyzed by bioinformatics method, and the expression profile of OsFWL3 gene was predicted. Two OsFWL3 knockout lines were obtained using CRISPR/Cas9 gene editing technology. Then wild type and Osfwl3 mutants were treated with ZnSO4 at seedling stage and filling stage, respectively. The phenotypes of plants and grains after treatment were analyzed, and the content variation of metal elements such as Zn was determined to explore the effects of OsFWL3 on the transport and accumulation of metal ions and seed quality. 【Result】The gene function of OsFWLs family is similar to some extent. OsFWL3 gene is highly expressed in anther and panicle, indicating that it is closely related to reproductive development of rice. The number of primary branches, grian length, grain thickness and 100-grain weight of Osfwl3 mutants are significantly larger than WT. OsFWL3 affects the content and distribution of Zn and other metal ions in rice seedlings and grains. The deletion of OsFWL3 gene affects the competitive transport of Zn, Cd and Mn from underground to above-ground, lower grain to central grain and husk to brown rice. 【Conclusion】OsFWL3 gene affects the distribution of Zn and other metal ions in rice grains and plants, and it plays an important role in regulating the growth and development of rice plants and grain size.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    HAN XuDong, YANG ChuanQi, ZHANG Qing, LI YaWei, YANG XiaXia, HE JiaTian, XUE JiQuan, ZHANG XingHua, XU ShuTu, LIU JianChao
    Scientia Agricultura Sinica. 2024, 57(21): 4175-4191. https://doi.org/10.3864/j.issn.0578-1752.2024.21.002

    【Objective】Genetic improvement for efficient utilization of maize nutrients represents a crucial method to ensure national food security. Exploring quantitative trait locus (QTL) and related candidate genes of nitrogen use efficiency can provide a theoretical basis for improving the efficiency of nitrogen fertilizer in maize and cultivating high-yield and high-efficiency maize varieties. 【Method】In this study, QTL mapping analysis in one recombinant inbred line (RIL) population constructed by KA105 and KB024 was performed for grain yield under two different nitrogen treatments, including the derived traits partial factor productivity from applied nitrogen (PFPN), low nitrogen tolerance coefficient (LNTC) and nitrogen agronomic efficiency (NAE). Concurrently, integrating the seedling transcriptome data of the parent KA105 under nitrogen treatment, differentially expressed genes were identified, and candidate genes associated with maize nitrogen use efficiency were mined through co-expression analysis. Subsequently, the selected candidate genes were validated using qRT-PCR. 【Result】Through mapping analysis, a total of 36 QTLs distributed across different chromosomes were detected, explaining 1.63% to 17.26% of the phenotypic variation. Among these, eight major QTLs with a phenotypic variation explanation rate exceeding 10% were identified, along with seven genetically stable QTLs commonly identified across different traits or environments. Notably, qNNGYP1 located on chromosome 1 has been repeatedly detected in previous studies, with a phenotypic explanation rate of up to 11.73%. Additionally, other QTLs (qNNGYP1, qPFPN1) co-located in this interval across different environments, suggesting it as a focal region for further investigation. Combining transcriptome data of seedlings under low nitrogen stress, 39 differentially expressed genes within these QTL intervals were identified, and 6 key genes were identified through co-expression network prediction. The result of qRT-PCR indicated that the expression trends of the candidate genes under both nitrogen treatments were consistent with the transcriptome data. Specifically, GRMZM2G366873 was involved in the regulation of auxin homeostasis and may participate in maize responses to low nitrogen stress, drought stress, and boron stress through auxin signal transduction, also regulating ear length. GRMZM2G414192 was involved in the response of the photosynthetic system to low nitrogen stress and was regulated by brassinosteroids. GRMZM2G414043 was associated with maize grain length and biomass, while GRMZM2G040642 may be involved in the long-distance signal transduction of nitrogen. 【Conclusion】In summary, a total of 36 QTLs were identified, distributed across chromosomes 1, 4, 5, 7, 8, and 9, including eight major QTLs (PVE>10%). The candidate genes GRMZM2G366873, GRMZM2G414192, GRMZM2G414043, and GRMZM2G040642 were identified as potential genes for maize nitrogen efficiency.

  • TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY
    LIWeiJing, WANGHongYuan, XUYang, LIHao, ZHAILiMei, LIUHongBin
    Scientia Agricultura Sinica. 2024, 57(18): 3551-3567. https://doi.org/10.3864/j.issn.0578-1752.2024.18.004

    【Objective】 The rice-crab co-culture is a predominant three-dimensional ecological cultivation model in northern Chinese rice fields. The water-soil interface is a key area for material cycling within this system. In this paper, studying the diversity and structure of microbial communities at this interface aimed to understand its evolution and support research on the ecological health of water and soil in rice-crab co-culture systems. 【Method】 Eight long-term rice monoculture systems and eight long-term rice-crab co-culture systems (>20 years) were selected in a typical rice-crab co-cultivation area in Panjin, Liaoning province. Based on measurements of physicochemical indicators of rice field water and soil, as well as high-throughput sequencing technology of the 16S rRNA gene, the study compared the effects of two rice cultivation systems on the properties and bacterial community structures of the water-soil interface in paddy fields. 【Result】 (1) The introduction of crabs significantly reduced the unique microbial communities at the water-soil interface. Specifically, the number of unique operational taxonomic units (OTUs) in surface water and interfacial soil decreased by 27.0% and 71.2%, respectively. However, the introduction of crabs had no significant effect on alpha diversity in surface water, but it reduced the richness of bacterial communities in interfacial soil. (2) The introduction of crabs significantly altered the structure and composition of the water-soil interface bacterial community. The introduction of crabs significantly increased the relative abundance of Proteobacteria (30.4%) and decreased the relative abundance of Acidobacteria (39.9%) in surface water. Simultaneously, it increased the relative abundance of Planctomycetes (21.1%) and decreased the relative abundance of Ignavibacteriae (15.1%) and Nitrospirae (21.7%) in interfacial soil. (3) Proteobacteria and Bacteroidetes were not only core species at the water-soil interface of rice field systems, but also key species in co-occurrence networks, playing important roles in stabilizing ecological networks. (4) The introduction of crabs into rice fields increased the complexity and stability of the bacterial co-occurrence network in the interface soil, but decreased it in the paddy field water. (5) Linear regression analysis showed that NO3-- N concentration in surface water and interface soil pH were the main driving factors influencing the diversity and stability of their respective bacterial community structures. 【Conclusion】 The introduction of crabs significantly altered the microbial community structure and diversity at the water-soil interface in rice fields. The increase in nutrient salts in the water posed a risk of reducing the stability of the aquatic microbial community. However, the rice-crab co-culture shaped a more stable bacterial community in the interface soil, which facilitated nutrient cycling and enhanced crop nutrient utilization efficiency.

  • ANIMAL SCIENCE·VETERINARY SCIENCE
    SUNYanYan, NIAiXin, YANGHanHan, YUANJingWei, CHENJiLan
    Scientia Agricultura Sinica. 2025, 58(5): 1017-1031. https://doi.org/10.3864/j.issn.0578-1752.2025.05.015

    Heterosis is a phenomenon where the offspring of genetically distinct populations exhibit superior vitality, reproductive capacity, and adaptability compared with the average of their parent populations, which is an important genetic resource. Heterosis plays a significant role in modern agriculture, contributing to increase yields and quality of livestock and crops, rapidly improve traits, accelerate the breeding of new varieties, and enhance genetic diversity, thereby efficiently boosting the production of animal husbandry and agriculture while reducing costs. Despite the discovery of heterosis is over a century ago, the elucidation of its genetic basis lags far behind its application in agricultural production. The study of the complex formation mechanism of heterosis is a classic and an active topic in the field of genetics and breeding, but the clear conclusions remain limited. In response to the characteristics of heterosis, scientists have successively proposed various hypotheses for its formation, such as the dominance hypothesis, overdominance hypothesis, and epistasis hypothesis, revealing that the genetic basis of heterosis was non-additive genetic effects. However, these hypotheses are based on the effects of single genes, which are overly idealized and simplistic. Explorations at different levels, such as DNA, RNA, and proteins, have successively discovered the coexistence of multiple genetic effects. Particularly in hybrid crops like rice and corn, the related researches have been continuously identified the loci of heterosis effects, enriched the understanding of the formation mechanism for heterosis in crops, and promoted the transformation of crop breeding technologies, such as precise molecular design breeding. Heterosis is also widely applied in the breeding of livestock and poultry. In developed countries with advanced animal husbandry, over 80% of commercial pork, chicken, and eggs are obtained from hybrid breeds. To efficiently apply heterosis in production for animal husbandry, it is necessary to predict heterosis in advance. New methods, such as the inter- and intra-group phenotypic variance ratio prediction, hybrid heritability prediction, and molecular marker prediction, have been developed to solve the long experimental cycle, environmental sensitivity, and high human and financial costs associated with traditional hybridization experiments for predicting heterosis. However, the accuracy of these prediction methods is limited. Heterosis involves in interaction of multiple levels, and because of the complex genetic background and long breeding cycle, it is still a big challenge for the study of the heterosis formation mechanism and accurate prediction methods. In recent years, the gradual application of sequencing technology has provided a new perspective for understanding the molecular regulatory network of heterosis in livestock and poultry. QTL mapping and genome-wide association study reveal the molecular mechanism of heterosis at the genomic level, and the identified molecular makers are applied in selection and breeding. Combined with multi-omics researches, such as transcriptomics and metabolomics, the key functional genes, variations, and metabolites affecting heterosis can be more precisely located, which facilitate hybrid improvement. This review elaborated the research progress in the formation mechanism and prediction methods for heterosis in the field of livestock and poultry. For looking forward to future, the researches will gradually clarify the complex mechanism of heterosis by integrating multi-omics sequencing data and bioinformatics analysis, in order to identify genes and molecular markers related to heterosis, and innovate new prediction methods, which will provide a more accurate direction for the utilization of heterosis.

  • TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY
    ZHANGSiJia, YANGJie, ZHAOShuai, LILiWei, WANGGuiYan
    Scientia Agricultura Sinica. 2025, 58(2): 238-251. https://doi.org/10.3864/j.issn.0578-1752.2025.02.003

    【Objective】Based on the long-term experiment in the North China Plain (NCP), the differences in soil nutrient and aggregate nutrient distribution between diversified crops and wheat-maize rotation systems were investigated. Additionally, it provided a comprehensive evaluation of soil quality indices (SQI), offering a scientific basis for enhancing soil quality and productivity in the NCP. 【Method】Four diversified crop rotation systems were evaluated, including spring sweet potato-winter wheat-summer maize (Psw-WM), spring peanut-winter wheat-summer maize (Pns-WM), spring sorghum-winter wheat-summer maize (Ps-WM), with winter wheat-summer maize (WM-WM) serving as the control. The soil samples from the 0-40 cm depth were collected during the second rotation in 2022, at the flowering and harvesting stages of winter wheat. The soil enzymes activities, aggregate stability, organic matter, and concentrations of nitrogen, phosphorus, and potassium in soil and aggregates of different sizes (>2.00 mm, 0.50-2.00 mm, 0.25-0.50 mm, and <0.25 mm) were assessed. The SQI for each crop rotation system was then comprehensively evaluated. 【Result】Compared with WM-WM, the three other crop rotations increased soil inorganic nitrogen content. Psw-WM significantly enhanced organic matter in the 0-20 cm layer, total nitrogen in soil aggregates (>2.00 mm, 0-10 cm), and organic matter in soil aggregates (>2.00 mm and 0.50-2.00 mm, 0-10 cm), which also increased cellulase, catalase, and alkaline protease activities. Pns-WM improved organic matter in the 20-40 cm layer and available potassium in soil aggregates (0.25-0.50 mm and >2.00 mm, 10-20 cm), as well as organic matter in soil aggregates (0-10 cm, >2.00 mm and 10-20 cm, >0.50 mm), which also increased sucrase, urease, and alkaline protease activities. Psw-WM improved the stability of 0-10 cm soil aggregates, while Pns-WM improved the stability of 0-30 cm soil aggregates. Both Pns-WM and Psw-WM significantly improved the SQI, with Pns-WM showing a higher improvement than Psw-WM. The path analysis revealed that the average weight diameter (MWD) of aggregates was a direct and significant affecting SQI. It also had a significant indirect positive effect on SQI by influencing inorganic nitrogen. Additionally, the increased organic matter led to a higher proportion of large aggregates, which significantly affected SQI indirectly. 【Conclusion】Legume (peanut) and root crop (sweet potato) rotations with wheat-maize rotations could significantly improve soil quality and enhance the soil nutrient supply capacity in the NCP.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    LUO JiangTao, ZHENG JianMin, DENG QingYan, LIU PeiXun, PU ZongJun
    Scientia Agricultura Sinica. 2024, 57(20): 3945-3956. https://doi.org/10.3864/j.issn.0578-1752.2024.20.001

    【Objective】Analyzing the yield and yield related traits of Sichuan wheat varieties from 2000 to 2020, providing reference for genetic improvement of yield in Sichuan wheat varieties. 【Method】From 2019 to 2022, a community trial design was used to measure the yield and related traits of 145 wheat varieties in Sichuan Province since 2001 to 2016, as well as 60 high-yield wheat varieties (Varieties with top yields in regional trials in Sichuan Province over the years) since 2000 to 2020. This data was used to analyze the trend of yield and yield related trait changes in Sichuan wheat cultivars cultivated from 2000 to 2020. 【Result】145 Sichuan wheat varieties from 2001 to 2016 have an average annual genetic gain of 37.20 kg·hm-2 or 0.66% in yield. Grain number per spike and effective spike number per unit area showed an increasing trend, while thousand grain weight and plant height showed a decreasing trend. Correlation analysis showed that effective spike number per unit area was positively correlated with yield. Path analysis showed that the continuous increase of effective spike number per unit area (annual increase 0.42×104/hm2 or 0.13%) was the main factor for the increase of yield potential of high-yielding varieties. The average annual yield genetic gain of 60 high-yield wheat varieties from 2000 to 2020 was 61.10 kg·hm-2 or 0.89%, the effective spike number per unit area showed an increasing trend, the plant height showed a decreasing trend, and the grain number per spike and thousand grain weight had almost no change. Correlation analysis shows that there was a significant positive correlation between yield and the number of effective ears per unit area. Path analysis showed that the continuous increase in effective spike number per unit area (with an average annual increase of 1.80×104/hm2 or 0.51%) was also a major factor in improving the yield potential of 60 high-yield wheat varieties in Sichuan from 2000 to 2020. 【Conclusion】The improvement and breeding of wheat yield heritage in Sichuan Province has made some progress, especially the improvement effect of high yield breeding is remarkable, and the yield level of wheat varieties in Sichuan Province is gradually increasing. The continuous increase in effective ears per unit area was the main factor for improving the yield potential of Sichuan wheat varieties. High grain number per spike and thousand grain weight are important foundations for high yield in Sichuan wheat, but their genetic improvement is in a bottleneck period. Increasing the effective spike number per unit area is the key to furtherly improve the yield of wheat in Sichuan.

  • SPECIAL FOCUS: OCCURRENCE AND CONTROL OF MIGRATORY PESTS
    TANGBin, LUOYanLin
    Scientia Agricultura Sinica. 2024, 57(20): 3986-3988. https://doi.org/10.3864/j.issn.0578-1752.2024.20.004
  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    DIAODengChao, LIYunLi, MENGXiangYu, JISongHan, SUNYuChen, MAXueHong, LIJie, FENGYongJia, LIChunLian, WUJianHui, ZENGQingDong, HANDeJun, $\boxed{\hbox{WANGChangFa}}$, ZHENGWeiJun
    Scientia Agricultura Sinica. 2025, 58(4): 617-634. https://doi.org/10.3864/j.issn.0578-1752.2025.04.001

    【Objective】The GRAS family constitutes a unique class of plant-specific transcription factors that play a pivotal role in plant development and stress response. To elucidate the function of GRAS family genes in wheat heat tolerance,which can provide genetic resources and theoretical foundation for wheat heat-resistant breeding.【Method】A potential heat stress-responsive transcription factor gene, TaGRAS34-5A, was identified through transcriptome analysis of TAM107 and Chinese spring wheat seedlings under high-temperature conditions. Subsequently, a bioinformatics analysis was performed on TaGRAS34-5A, and a phylogenetic tree was constructed to elucidate its molecular characteristics. The expression pattern of TaGRAS34-5A under various stresses, including high temperature, abscisic acid (ABA), ethylene (ETH), and salicylic acid (SA) treatments, were examined using real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) method. The subcellular localization of the TaGRAS34-5A protein was determined using wheat protoplast transient expression technique. Furthermore, the heat tolerance function of TaGRAS34-5A was validated using the heterologous expression system of Saccharomyces cerevisiae and the BSMV:VIGS (Barley stripe mosaic virus: Virus-Induced Gene Silencing) silencing technique. potential interacting proteins of TaGRAS34-5A were screened using yeast two-hybrid technology, and the heat tolerance function was verified, providing preliminary insights into its heat tolerance mechanism.【Result】TaGRAS34-5A, equipped with a characteristic GRAS domain and belongs to the GRAS transcription factor family, is localized to both the cell nucleus and cytoplasm. Bioinformatics analysis indicates that the TaGRAS34-5A promoter contains a large number of hormone response elements and light response elements, and it is most closely related to TaSCL14, OsGRAS23, and AtSCL14 in terms of phylogenetic relationships, suggesting its potential function in responding to oxidative stress. Its expression is upregulated under high-temperature, ethylene (ETH), abscisic acid (ABA), and salicylic acid (SA) treatments, peaking at 4, 6, 0.5, and 12 hours post-treatment, respectively, with the most significant induction observed under heat stress and SA. Functional assays in yeast demonstrated that heterologous expression of TaGRAS34-5A enhances the heat tolerance of the yeast. The results of BSMV:VIGS transient silencing experiment showed that after the 42 ℃ high-temperature treatment, TaGRAS34-5A silenced plants exhibited decreased chlorophyll content, reduced POD enzyme activity, increased cellular peroxidation, and decreased heat tolerance compared to the control. Preliminary studies on the heat tolerance mechanism suggest that TaGRAS34-5A exhibits strong transcriptional self-activation activity.it may modulate wheat heat tolerance by interacting with proteins such as the bZIP family transcription factor HBP-1b and the E3 ubiquitin ligase hel2, thereby regulating cellular redox homeostasis and detoxification processes, positively influencing the heat tolerance of wheat.【Conclusion】TaGRAS34-5A is induced by heat, ABA, ETH, and SA, and its encoded protein is located in the nucleus and cytoplasm. It exhibits transcriptional activation activity. Heterologous overexpression of TaGRAS34-5A enhances the heat tolerance of Saccharomyces cerevisiae. Silencing TaGRAS34-5A in wheat plants increases cellular peroxidation, decreases chlorophyll content, and reduces heat tolerance. TaGRAS34-5A may regulate the heat tolerance of wheat by modulating cellular redox state and detoxification processes.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    SHANGHang, CHENGYuKun, RENYi, GENGHongWei
    Scientia Agricultura Sinica. 2024, 57(18): 3507-3521. https://doi.org/10.3864/j.issn.0578-1752.2024.18.001

    【Objective】 Starch is the main component of wheat kernel and plays an important role in processing. The gelatinization characteristic of starch is an important index to evaluate its quality. The genetic variation of starch gelatinization was studied to provide basis for improving wheat quality. 【Method】 Seven starch gelatinization traits, including gelatinization temperature, peak time, peak viscosity, trough viscosity, final viscosity, decay value and recovery value, were phenotypically determined in 205 winter wheat varieties. Genome-wide association analysis was performed using 90K chip, and haplotype analysis was performed on the stable and significant sites found. 【Result】 The seven characteristics, such as pasting temperature, showed abundant variation in different environments, and the coefficient of variation of attenuation value was the largest (29.31%-31.14%). There were significant differences among genotype, environment and genotype × environment, and the generalized heritability was 0.69-0.86. Through genome-wide association analysis, we found 198 loci that showed significant associations with seven traits. It was distributed in 20 other linked groups except 6D chromosome. There were 58 sites that were stable in 2 or more environments, involving all 7 traits, such as pasting temperature (10), peak time (5), peak viscosity (12), trough viscosity (10), final viscosity (7), break down (4) and set back (10), which could explain 5.54%-22.21% of genetic variation, twenty-one new sites were identified. By haplotype analysis of multiple effector sites that exist in multiple environments and have high phenotypic contribution, Four haplotypes, Hap1 (66.84%), Hap2 (16.84%), Hap3 (9.70%) and Hap4 (6.63%), were found at Kukri_c17417_407 on chromosome 4A, which were significantly related to peak viscosity and break down. Where Hap2 is the peak viscosity and high break down. (P<0.0001). The distribution frequency of varieties (lines) containing haplotype Hap2 in different ecological regions was from high to low as Huanghuai winter wheat region>foreign varieties>Southwest winter wheat region>Middle and lower reaches of Yangtze River winter wheat region>Northern winter wheat region. There were 11 single cause multieffect sites, among which there were 3 multiple effect sites associated with final viscosity, set back, peak time and trough viscosity. Jagger_c4026_328 and other 11 stable genetic loci located on 1B, 2A, 3A, 3B, 4A, 4B, 5B and 6B were mined, and 11 candidate genes that might be related to wheat starch gelatinization traits were screened. 【Conclusion】 In this study, RVA parameters had high heritability, and the RVA parameters of wheat starch were different in different environments. In this study, RVA parameters had high heritability, and the RVA parameters of wheat starch were different in different environments. 58 stable loci were detected that were significantly associated with starch gelatinization traits, and 4 different haplotypes were identified on chromosome 4A that were significantly associated with peak viscosity and break down, and 11 candidate genes related to starch gelatinization were screened, which could provide help for marker-assisted high-quality wheat breeding.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    WANGWei, WUChuanLei, HUXiaoYu, LIJiaJia, BAIPengYu, WANGGuoJi, MIAOLong, WANGXiaoBo
    Scientia Agricultura Sinica. 2025, 58(1): 10-29. https://doi.org/10.3864/j.issn.0578-1752.2025.01.002

    【Objective】Based on whole genome identification and analysis of soybean LOX gene family members, to understand the taxonomic evolutionary relationships of each member, to study the expression specificity of each gene member in different tissues and their response to abiotic stress, which provided a theoretical basis for further research on the molecular characteristics, evolutionary process, and function of the LOX gene family. 【Method】Based on the LOX protein sequences of rice and Arabidopsis species in Ensembl database, BLASTP alignment of homologous LOX protein sequences in soybean whole genome database was performed, and MEGA X software was used to construct a phylogenetic tree; Using website MEME for protein conserved motif analysis; Using online software GSDS 2.0 to analyze gene structure; Using TBtools for chromosome localization drawing; Analyze soybean LOX family replication genes using McscanX; Using the PlantCARE website to predict the promoter elements of soybean LOX gene family; Draw gene expression heatmaps of soybean under different tissues and abiotic stress using TBtools, and develop molecular markers for the excellent allele variant GmLOX15A1-G/A significantly correlated with 100-seed weight.【Result】A total of 43 LOX genes were identified in soybean, unevenly distributed on 13 chromosomes. Collinearity analysis indicates that the GmLOX gene has undergone extensive replication during the evolutionary process. Meanwhile, 39 different types of cis regulatory elements were detected in the LOX gene promoter, indicating that they may be involved in different pathways such as growth and development, light response, stress response, and hormone induction. Expression pattern analysis revealed that the LOX gene has different levels of expression in different tissues of soybean, indicating that members of this family have tissue and spatiotemporal expression specificity. Under drought stress conditions, the GmLOX gene was significantly differentially expressed in soybean roots and leaves (P<0.05). Among them, GmLOX3A3, GmLOX7A1, GmLOX20B1, GmLOX13A1, and GmLOX20A2 were significantly upregulated or downregulated in roots and leaves, suggesting that the GmLOX gene may play an important role in response to stress. At the same time, it was found that GmLOX15A1 is highly expressed in grain tissue and there is an excellent G/A allele variation in the seventh exon of the gene coding region. Molecular markers were developed for this variant site, and the correlation between different haplotypes of GmLOX15A1 and 100-seed weight was analyzed using 1 200 soybean germplasm resources from different ecological regions over a period of 2 years. The results showed that compared to the GmLOX15A1-A genotype, the average 100-seed weight of soybean germplasm carrying the GmLOX15A1-G allele gene increased by 2.33 g (P<0.001). 【Conclusion】A total of 43 members of the LOX family were identified in soybeans, which can be divided into 3 subfamilies. The promoter region of the GmLOX gene contains a large number of cis acting elements that respond to hormones and stress, playing different roles in drought stress response. Among them, GmLOX15A1 is highly expressed in grain tissue and there is an excellent G/A allele variation in the seventh exon of the coding region of this gene. Compared with the GmLOX15A1-A genotype, the average 100-seed weight of soybean germplasm carrying the GmLOX15A1-G allele gene is significantly increased by 2.33 g. This locus can be used as an excellent haplotype for genetic improvement of soybean grain size.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    QIXiaoLei, WANGJun, LÜGuangDe, MUQiuHuan, MIYong, SUNYingYing, YINXunDong, QIANZhaoGuo, WANGRuiXia, WUKe
    Scientia Agricultura Sinica. 2024, 57(22): 4391-4401. https://doi.org/10.3864/j.issn.0578-1752.2024.22.001

    【Objective】Taikemai33, derived from a cross between Zhengmai366 and Huaiyin9908, is a new released wheat cultivar with high quality, high yield, and excellent disease resistance, which has a broad genetic base, and a high potential for application in wheat production. The objective of this study is to dissect the genetic composition of Taikemai33 to provide information for parental selection to use this cultivar to develop more new wheat cultivars. 【Method】Taikemai33 and its pedigree parents including Zhengmai366, Huaiyin9908, Yumai47, PH82-2-2, Yumai13, Yumai 2 hao, Bainong3217, Yanda24, Xiannong39, Fengchan 3 hao and Funo were screened using the 55K wheat SNP chip to dissect the genomic composition of Taikemai33 to evaluate the genetic contributions of each parental line to Taikemai33. 【Result】The similarity coefficient between Taikemai33 and its pedigree parents ranged from 0.72 to 0.93, and the genetic composition of Taikemai33 was highly similar to Zhengmai366, the pedigree mother parent, with a genetic similarity coefficient of 0.93. SNP marker analysis showed that the pedigree parents contributed different proportion to the genome of Taikemai33, with the pedigree mother contributed 66.57%, whereas the pedigree father contributed 33.43%, indicating that Taikemai 33 inherits more genetic materials from the maternal lineage. Furthermore, the pedigree mother contributed 71.0%, 85.0% and 49.4% to subgenome A, B and D of Taikeimai33, whereas those were 29.0%, 15.0% and 50.6% contributed by the pedigree father. For each chromosome, the pedigree mother contributed more on chromosome 1A, 2A, 3A, 4A, 7A, 1B to 7B, 1D and 2D, whereas the pedigree father contributed more on chromosome 5A, 4D, 6D and 7D. The contributions of the pedigree parents on 6A, 3D and 5D were equal. Taikemai33 genotype map showed that the contribution loci of the pedigree mother were distributed in clusters on chromosome 1A, 5A, 7A, 2B, 7B, 2D, with those from the pedigree father were on chromosome 4A, 5A, 6D, 7D. Interestingly, among the polymorphic SNP loci, between Zhenmai366 and Huaiyin9908, Taikemai33 showed 109 loci that were absent in both parents, distributing on 19 chromosomes except 1A and 6A. Chromosome 4A, 2B, 6B and 7D of Taikemai33 confer most of the polymorphic SNPs in clusters with cluster number of 10, 9, 11, and 9. 【Conclusion】We constructed the genotype map and dissected the genetic composition of Taikemai33, determined the loci contributed by the pedigree parents and identified that Taikemai33 inherited more genetic materials from the pedigree mother and conferring some specific loci different with the pedigree parents.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    XUYiHeng
    Scientia Agricultura Sinica. 2025, 58(5): 831-839. https://doi.org/10.3864/j.issn.0578-1752.2025.05.001

    Gene-edited crops, the product of the intersection between biotechnology and agricultural science, represent a crucial direction in the development of modern agriculture. With the rapid advancement of the CRISPR-Cas9 system, the scientific research and commercial development of crop trait improvement have gradually shifted towards a “technology-driven” path, which has not only overturned traditional crop cultivation methods but also fundamentally propelled humanity’s exploration of crop research. Nevertheless, the phenomenon of patenting fundamental research tools has sparked widespread controversy within academia and profoundly impacted the sharing and utilization of crop resources. Private entities patenting CRISPR-Cas9 technology restrict other researchers and farmers’ opportunities to explore and harness genetic resources. This practice not only hinders scientific progress but also violates the fundamental consensus that genetic resources should be shared by all humanity. The sharing and openness of crop resources are crucial for the sustainable development of global agriculture and ecological balance, serving as a necessary condition for safeguarding public interests. A key issue that the governance of biotechnology patents urgently needs to address is how to reasonably allocate benefits and risks among traditional communities, researchers, research investors, and the public. This is also essential for constructing a new scientific ethics framework and regulating emerging technologies. However, China’s policy responses in this area are still insufficient. To mitigate the negative effects stemming from the exclusivity of patents, it is imperative to reassess and reconstruct the framework of relevant systems. Firstly, we should adhere to the principle of moral utility, emphasizing the public nature of scientific research and its social responsibilities, while carefully considering the “harmful” nature of inventions to social morality. Secondly, implementing a mandatory disclosure system for biological genetic resources is a crucial step towards achieving transparency and fairness, with “applicants truthfully disclosing the actual origin of crop genes based on the principle of good faith” elevated to a mandatory norm. Lastly, the open licensing of fundamental patented technologies can draw inspiration from the experience of open-source software, encouraging more researchers to participate in the exploration of crop resources through the open sharing of research tools, thereby facilitating broader scientific collaboration and the transformation of research outcomes.

  • SPECIAL FOCUS: MINING AND UTILIZATION OF CROP DISEASE RESISTANCE AND INSECT-RELATED GENES
    XIONG ShangYe, ZHANG Xiang, LIANG BaoHui, YE YangDong, LI YuYang, ZHU Xiao, ZHU ZhiHong, GUAN HuaZhong, ZHANG Shuai, WU JianGuo, HU Jie
    Scientia Agricultura Sinica. 2024, 57(23): 4619-4631. https://doi.org/10.3864/j.issn.0578-1752.2024.23.004

    【Objective】 This study aims to discover new quantitative trait loci (QTLs) for resistance to the brown planthopper (BPH) in rice by utilizing a genetic population and to assess the pyramiding effects of these QTLs, thereby providing crucial genetic materials and resources for breeding insect-resistant rice. 【Method】 A recombinant inbred line (RIL) population derived from a cross between susceptible NPB and resistant Jiafuzhan was used, combined with seedling stage resistance evaluation and extreme mixed pool sequencing (BSA-seq) to map BPH resistance QTLs. Further, fine mapping, candidate gene identification, pyramiding effect analysis, and mixed-pool transcriptome sequencing (BSR-seq) were employed to elucidate the physiological and molecular mechanisms mediated by these QTLs. 【Result】 BSA-seq identified two major resistance QTLs on chromosomes 1 (30-32 Mb) and 4 (5-7 Mb), named QBPH1 and QBPH4, respectively. Interval-linked molecular markers confirmed the authenticity of these QTLs. QBPH4 coincides with previously cloned BPH3 and BPH15, while QBPH1 represents a newly discovered QTL. High-density markers and recombinant analysis further narrowed the QBPH1 region to 30.61-30.65 Mb. This analysis identified Os01g53294 and Os01g53330 as reliable candidate genes, which code for a respiratory burst oxidase protein B and an anthocyanin 5,3-O-glucosyltransferase, respectively. In evaluations of seedling resistance, brown planthopper honeydew area and weight, insect weight gain, lethality, and preference, comparisons between QBPH1 and QBPH4 single genes and their polymerized lines revealed no significant enhancement in resistance. Both QBPH1 and QBPH4 mediated antibiosis and antixenosis mechanisms with varying effects. BSR-seq analysis highlighted significant enrichment of differentially expressed genes (DEGs) involved in transcriptional regulation, protein phosphorylation, and redox processes among different QBPH1 alleles. Additionally, genes associated with jasmonic acid (JA) synthesis and signaling pathways were significantly upregulated in resistant materials, confirmed by RT-qPCR experiments. 【Conclusion】 A novel BPH resistance QTL, QBPH1, was successfully identified on chromosome 1 of rice. QBPH1 mediated both antibiosis and avoidance against BPH, though its aggregation effect with another QTL was not significant. QBPH1 may mediate defense mechanisms against BPH through involvement in the JA pathway. Based on this, Os01g53294 and Os01g53330 have been validated as reliable candidate genes for QBPH1.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    SUXiaoYu, TANZhengWei, LIChunMing, LILei, LUDanDan, YUYongLiang, DONGWei, ANSuFang, YANGQing, SUNYao, XULanJie, YANGHongQi, LIANGHuiZhen
    Scientia Agricultura Sinica. 2024, 57(24): 4825-4838. https://doi.org/10.3864/j.issn.0578-1752.2024.24.001

    【Objective】This study aimed to explore the differences in genome-wide DNA methylation patterns and their relationships with associated gene expression in different heat-tolerant sesame varieties under high temperature stress, in order to gain a deeper understanding of the regulatory mechanisms of DNA methylation in sesame's response to high temperature stress, and to provide a theoretical basis for heat tolerance breeding in sesame. 【Method】Two sesame varieties, Zhengtaizhi 3 (heat-tolerant) and Shandong White Sesame (heat-sensitive), were selected as experimental materials and cultivated under high temperature (41 ℃) and control (30 ℃) conditions for 10 days. Nanopore sequencing technology was used to conduct methylation sequencing of the genomic DNA of these two sesame varieties, and transcriptome sequencing was performed to analyze changes in the expression of associated genes. Minimap 2 software was utilized for reference genome sequence alignment, and Tombo software was employed to detect 5mC, CpG, and 6mA methylation sites. Differentially methylated regions (DMRs) were identified based on a genome segmentation approach. Finally, functional annotation and pathway analysis of DMR-associated differentially expressed genes (DMR-DEGs) were conducted using GO, COG, and KEGG databases. 【Result】Under high temperature stress, significant changes were observed in the genome-wide DNA methylation patterns of both Zhengtaizhi 3 and Shandong White Sesame. Specifically, the m6A and cytosine methylation (mC) contents of Zhengtaizhi 3 increased, while those of Shandong White Sesame decreased. A total of 621 DMRs (Zhengtaizhi 3) and 374 DMRs (Shandong White Sesame) were identified across the entire genome, mainly distributed in promoter and intergenic regions. Further analysis revealed that these DMRs were significantly associated with 113 DMR-DEGs (Zhengtaizhi 3) and 56 DMR-DEGs (Shandong White Sesame), respectively, and that demethylated DMRs were closely related to upregulated gene expression. Functional annotation results indicated that these DMR-DEGs were primarily involved in biological processes such as carbohydrate transport and metabolism, posttranslational modification, protein turnover, signal transduction, and secondary metabolite biosynthesis. 【Conclusion】This study revealed the differences in genome-wide DNA methylation patterns and their relationships with associated gene expression in different heat-tolerant sesame varieties under high temperature stress. Zhengtaizhi 3, a heat-tolerant sesame variety, regulated the expression of related genes by increasing DNA methylation levels under high temperature stress, while Shandong White Sesame, a heat-sensitive variety, exhibited a decreasing trend in methylation levels. In particular, the dynamic changes in CpG site methylation played a crucial role in regulating sesame's response to high temperature stress. These findings provide new insights and theoretical support for understanding the mechanisms of sesame heat tolerance and for heat tolerance breeding.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    MAIChunYan, LIUYiKe, LIUHongWei, LIHongJie, YANGLi, WUPeiPei, ZHOUYang, ZHANGHongJun
    Scientia Agricultura Sinica. 2024, 57(19): 3719-3729. https://doi.org/10.3864/j.issn.0578-1752.2024.19.001

    【Objective】To develop high-yielding and FHB-resistant wheat cultivars in the Yellow and Huai River Valley Winter Wheat Zone (YHWZ), simultaneously improving of yield and resistance was conducted in this study.【Method】Using the elite parent dwarf male sterile (DMS) wheat combined with double haploid (DH) technology and molecular marker assisted selection (MAS) of Fhb1 (DMS wheat molecular breeding strategy), DH lines were developed using Sumai 3 as a donor (FHB- resistant parent) and Zhoumai 16’s DMS wheat, Zhoumai 16, Lunxuan 136 and Lunxuan 6 as recipient parents. The agronomic traits (plant height, heading date, yield, etc.) and FHB resistance were evaluated for these DH lines.【Result】A total of 51 Fhb1-DH lines characterized by facultative growth habit, semi-dwarf and white grains were selected using this strategy. The average number of infected spikelets of 51 lines were 5.7 and 7.3 at the 2020Henan and 2020Beijing sites, respectively, and average disease severities were 27.7% and 35.2%, which is not different from moderately susceptible control Huaimai 20. There was no significant difference in grain yield per hm2 between the mean performance of the 51 lines and the control Zhoumai 18. DH116 (Lunxuan 20), a promising line from the 51 lines, was further evaluated for FHB resistance and agronomic traits in multiple environments. The resistance of Lunxuan 20 to FHB was significantly improved, and no significant difference was found in the number of infected spikelets or disease severity between Lunxuan 20 and moderately or highly resistant controls at four sites. Lunxuan 20 showed slightly greater grain yield per hm2, and significantly higher number of spikelets per spike and thousand grain weight (P<0.05), earlier heading date and shorter plant height (P<0.05) than the control Zhoumai 18 in two environments. The grain yield per hm2 of Lunxuan 20 was 4.6% and 1.7% higher than the control cultivar Bainong 207 in the two list trials of Henan Province, and 3.5% higher than Bainong 207 in the demonstration trial. Resistance of Lunxuan 20 to FHB ranged from moderate susceptibility to moderate resistance in two-year list tests using the single-floret injection and spray inoculation methods. Lunxuan 20 carries the semi-dwarfing gene Rht-D1b at the Rht-D1 locus, and the recessive alleles vrn-A1, vrn-B1 and vrn-D1 associated with the winter growth habit at the Vrn-A1, Vrn-B1 and Vrn-D1 loci. Based on the wheat 660K single nucleotide polymorphisms (SNPs), 64.7% of the SNPs were shared by Lunxuan 20 and its parents, and the direct genetic contributions of Zhoumai 16, Lunxuan 136, Lunxuan 6 and Sumai 3 to Lunxuan 20 were 69.8%, 12.6%, 6.1% and 11.5%, respectively.【Conclusion】A high-yielding and FHB-resistant wheat cultivar Lunxuan 20 was bred using the DMS wheat molecular breeding strategy.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    ZHUJunJie, ZHANGXinYue, PANMengYing, ZHANGJingWen, ZHENGQi, LIYuLing, DONGYongBin
    Scientia Agricultura Sinica. 2024, 57(18): 3522-3532. https://doi.org/10.3864/j.issn.0578-1752.2024.18.002

    【Objective】 Grain size and weight are the important factors affecting the yield of maize. The EIN3/EIL gene family is a sort of key transcription factors in the ethylene signaling transduction pathway, and the functions and regulatory mechanisms of the EIN3/EIL gene ZmEIL9 were analyzed in maize kernel development to elucidate its molecular mechanisms.【Method】 The expression patterns of ZmEIL9 in maize kernel at different developmental stages were analyzed by bioinformatics and RT-qPCR. The multiple sequence alignment of ZmEIL9 and its homologs from different species was performed, and the phylogenetic trees was constructed based on the neighbor-joining method. The sequence characteristics of ZmEIL9 protein were analyzed, and subcellular localization of ZmEIL9 was performed. The insertion mutants of Mu transposon and CRISPR/Cas9 knockout mutants of ZmEIL9 were screened, and the agronomic traits including grain filling rate, storage substances such as starch granule and protein content were analyzed. 【Result】 According to the members of EIN3/EIL family in maize, phylogenetic trees showed that ZmEIL9 was closely related to ZmEIL1 and SbEIL1. In the transcriptomic database of maize inbred line B73, the expression levels of ZmEIL9 were higher in the grain at early and late developmental stages. However, the expression levels were higher in inbred line N04 at the middle and late developmental stages. ZmEIL9 encoded 644 amino acids in the inbred lines Dan232 and N04, while its homolog in inbred line B73 has 642 amino acids. Subcellular localization analysis indicated that ZmEIL9 was localized in nucleus. The ZmEIL9 mutants with different Mu transposon insertion sites and CRISPR/Cas9 knockout mutants with amino acid frameshift mutations were obtained, respectively. The plant height, grain length, and 100-grain weight of Mu mutants and knockout mutants were significantly lower than those of its wild counterpart. The grain dry weights at different developmental stages were also analyzed, and the grain filling rates of Zmeil9 mutant were lower than those of the wild type. The starch granules of Zmeil9 mutant were significantly smaller and had an irregular shape based on scanning electron microscopy (SEM) observations. The contents of total starch and the concentration of zein protein in the Zmeil9 mutant were significantly lower than those in the control. 【Conclusion】ZmEIL9 plays an important regulatory role in the kernel development of maize.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    WUChuanLei, HUXiaoYu, WANGWei, MIAOLong, BAIPengYu, WANGGuoJi, LINa, SHUKuo, QIULiJuan, WANGXiaoBo
    Scientia Agricultura Sinica. 2024, 57(22): 4402-4415. https://doi.org/10.3864/j.issn.0578-1752.2024.22.002

    【Objective】Polymerizing soybean high oil genotypes aims at breeding varieties with higher oil content to improve economic efficiency and nutritional value. It is of great significance to increase agricultural output, reduce processing costs and meet global demand for vegetable oil growth.【Method】Glyma.18G027100 C2 gene family was identified by bioinformatic analysis method at the whole genome level. A total of 66 soybean C2 gene family members were identified, named GmC2-01.1-GmC2-20.2 according to chromosome position. Tissue pattern analysis revealed that 7 genes were highly expressed in grains among 66 C2 family genes (GmC2-03.6, GmC2-02.7, GmC2-07.2, GmC2-18.1, GmC2-18.4, GmC2-19.1 and GmC2-20.2). In order to analyze the effect sites of these genes on soybean oil content, SNP sites in the coding regions of these genes were obtained from SFGB database. Correlation analysis of oil content in two years showed that GmC2-18.1 has SNP loci that significantly affect oil content. The genetic diversity of GmC2-18.1 coding region was analyzed by 12 extreme materials. There was a G/A mutation at 2 038 273 bp in coding region of Wm82.a2.v1 version, which regulated seed oil content. It was preliminarily speculated that this gene played a role in seed development or nutrient accumulation. Then, SNP/InDel molecular markers were developed for GmC2-18.1-G/A gene combined with InDel natural allelic variation site 225 bp upstream of the start codon of GmSWEET39, T/C natural allelic variation site at 8 381 058 bp in coding region of GmST1, A/C natural allelic variation site at the third exon of 41 854 422 bp in coding region of GmMFT. 1 200 soybean germplasm resources from three ecological regions in China were identified by markers in 2 years.【Result】Analysis of variance showed that GmC2-18.1-G, GmSWEET39-Deletion, GmST1-T and GmMFT-A significantly increased oil content by 1.72, 1.95, 1.58 and 2.06 percentage points (P<0.01). The results showed that the average oil content of soybean seeds carrying GmC2-18.1-G, GmSWEET39-Deletion, GmST1-T and GmMFT-A high-oil allele type (PFAT-1) was 22.89%, which increased by about 4.5% compared with that carrying GmC2-18.1-A, GmSWEET39-Insertion, GmST1-C and GmMFT-C low-oil allele type (PFAT-14). 5 percentage points, the contribution rate to oil content is about 21.69%. 【Conclusion】Based on the markers developed above, 115 PFAT-1 high oil alleles were screened.

  • SPECIAL FOCUS: MINING AND UTILIZATION OF CROP DISEASE RESISTANCE AND INSECT-RELATED GENES
    DIAO ZhiJuan, CHEN LiZhe, WANG Xun, LU Ling, LIU Yan, ZHANG Jing, XIA Na, TANG DingZhong, LI ShengPing
    Scientia Agricultura Sinica. 2024, 57(23): 4593-4606. https://doi.org/10.3864/j.issn.0578-1752.2024.23.002

    【Objective】 Rice blast is one of the main diseases that threaten rice yield and quality. OsBSK1-2 has been found to be involved in rice blast resistance regulation. Previously, OsCBSX4, a cysteine sulfide-β-Synthase, was identified by screening the proteins that interact with OsBSK1-2. The purpose of this study was to verify the interaction between OsBSK1-2 and OsCBSX4, and clarify the function and molecular mechanism of OsCBSX4 in rice blast resistance, providing a theoretical basis for rice disease resistance breeding.【Method】 Co-immunoprecipitation, bimolecular fluorescence complementation and luciferase complementation assays were used to determine the interaction between OsBSK1-2 and OsCBSX4. Then, quantitative PCR and agrobacterium- mediated transient transformation in N. benthamiana were used to detect the gene expression pattern and protein localization of OsCBSX4. Subsequently, OsCBSX4-knockingout and OsCBSX4-overexpressing plants were generated via CRISPR/Cas9 technology and Agrobacterium-mediated genetic transformation, respectively, and their resistance to rice blast was determined by inoculation with M. oryzae. Moreover, the immune responses induced by chitin and M. oryzae in the oscbsx4 mutant were analyzed using ROS burst and DAB staining assays respectively. In the end, the interaction between OsCBSX4 and OsRbohB was verified via bimolecular fluorescence complementation and split-luciferase complementation imaging assays, and the impact of the metabolite of OsCBSX4 on rice blast resistance was determined using the detached leaf inoculation method. The studies above will reveal the immune function and molecular mechanism of OsCBSX4.【Result】 The interaction between OsCBSX4 and OsBSK1-2 was verified by CoIP, LCI and BiFC assays. Compared to the wild type, the oscbsx4 mutant showed more disease lesions after inoculation with M. oryzae by the spray method, as well as a larger lesion area and greater fungal growth after inoculation with M. oryzae by the punch method, suggesting that knocking out OsCBSX4 decreased rice blast resistance. Moreover, the expression of the pathogenesis-related genes, OsPR5 and OsPR10, and the H2O2 accumulation induced by M. oryzae infection and the ROS burst induced by chitin treatment were reduced in the oscbsx4 mutant. Compared with the wild type, OsCBSX4 overexpressing plants showed a smaller lesion area and less fungal growth after inoculation with M. oryzae by the punch method, suggesting that overexpression of OsCBSX4 increased rice blast resistance. In addition, we found that OsCBSX4 can interact with OsRbohB, a key regulator of rice ROS production and treating rice with L-cysteine, a metabolite of OsCBSX4, does not affect rice blast resistance. 【Conclusion】 OsCBSX4 is an important component of OsBSK1-2 signaling and positively regulates rice blast resistance. OsCBSX4 may mediate ROS production by interacting with OsRbohB, thereby regulating rice immunity.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    WANGXiaoJun, WANGJinLan, JUZeLiang, LIANGGuoLing, JIAZhiFeng, LIUWenHui, MAXiang, MAJinXiu, LIWen
    Scientia Agricultura Sinica. 2024, 57(19): 3730-3742. https://doi.org/10.3864/j.issn.0578-1752.2024.19.002

    【Objective】In order to explore the adaptability of 10 oat (Avena sativa) varieties in the Qinghai Lake area and screen out the high-yield and high-quality oat varieties suitable for planting in this area, so as to provide data support for high-yield and high-quality forage production in this area and similar areas. 【Method】In this study, 10 oat varieties (Avena sativa cv. Qinghai No.444, A. sativa cv. Baiyan No.7, A. sativa cv. Qingyan No.4, A. nuda cv. Qingyou No.3, A. sativa cv. Qingyin No.2, A. sativa cv. Qingyan No.3, A. sativa cv. Lena, A. sativa cv. Qinghai, A. sativa cv. Qingyan No.1 and A. sativa cv. Longyan No.1) commonly cultivated in Qinghai province were used. The experiment was established using a randomized complete block design. Three experimental blocks, located at least 3 m away from each other, were randomly chosen. Each block contained 10 different oat varieties plots, for a total of 30 plots. The area of each plot was 3 m × 5 m. The experiment was sown in strip. The row spacing was 25 cm and the sowing depth was 3-4 cm. According to the thousand seed weight, purity and germination rate of each variety, the seeding rate of each variety was calculated according to the seedling protection number of 6.75 million plants/hm2. Moreover, the diammonium phosphate (150 kg·hm-2) and urea (75 kg·hm-2) were used as base fertilizer. The seeds were sown on May 16, 2022 and May 19, 2023, and field observations and sample collection were conducted on September 23, 2022 and September 26, 2023, respectively. The production performance and nutritional quality of oat varieties were analyzed, and the piecewise structural equation model was used to explore how varieties, planting years and their interactions affected nutritional quality via agronomic traits and yield traits. Furthermore, the multi-criterion decision model-TOPSIS (Technique for order preference by similarity to an ideal) was used to comprehensively evaluate the various indexes of the tested oat varieties. 【Result】Our results demonstrated that A. sativa cv. Qingyan No.3 had the highest plant height (89.4-92.5 cm), and the lowest acid detergent fiber (34.8%-34.9%) and neutral detergent fiber (51.8%-53.4%). The A. sativa cv. Qingyan No.4 had the most tillers number (2.7-3.6/plant) and the lowest crude ash content (10.9%-11.3%). The highest of forage yield, crude protein, relative feeding value were found in A. sativa cv. Qingyan No.3 and A. sativa cv. Qingyan No.4. while the stem/leaf ratio of the A. sativa cv. Qingyan No.3 and A. sativa cv. Qingyan No.4 were significantly lower than that of other varieties. The highest crude fat was found in A. sativa cv. Qingyan No.1 (3.8%-3.9%). The Pearson correlation analysis showed that the oat yield was positively correlated with crude protein content and relative feeding value, but negatively correlated with acid detergent fiber and crude ash. The stem/leaf ratio was positively correlated with acid detergent fiber and neutral detergent fiber, but negatively correlated with crude protein and relative feeding value. The structural equation model analysis showed that the varieties, planting years and their interactions had direct effects on the oat nutritional quality, and indirectly affected the nutritional quality by affecting plant height, tillering number, stem/leaf ratio and hay yield. The total effect value of stem/leaf ratio was the highest, which was -0.37.【Conclusion】The comprehensive evaluation of TOPSIS model showed that A. sativa cv. Qingyan No.4 and A. sativa cv. Qingyan No.3 could not only maintain higher production performance, but also have higher nutritional quality, which are ideal oat varieties for planting in Qinghai Lake area.

  • SOIL & FERTILIZER·WATER-SAVING IRRIGATION·AGROECOLOGY & ENVIRONMENT
    ZHANGHaoXin, YUShengYue, LEIQiuLiang, DUXinZhong, ZHANGJizong, ANMiaoYing, FANBingQian, LUOJiaFa, LIUHongBin
    Scientia Agricultura Sinica. 2025, 58(8): 1564-1578. https://doi.org/10.3864/j.issn.0578-1752.2025.08.008

    【Objective】 This study explored the applicability of the RothC model for simulating soil organic carbon (SOC) dynamics in dryland and paddy fields in Northeast China and evaluated the impact of various calibration methods on simulation performance.【Method】 This study selected one typical dryland and one typical paddy field as long-term experimental sites. The dryland experiment was conducted at the Heilongjiang Agricultural Ecology Experimental Station of the Chinese Academy of Sciences (2004-2015), and the paddy field experiment utilized data from the 850 Farm (2010-2017). At each experimental site, two treatments were selected for model simulation validation and performance evaluation: one with fertilization only, without straw return (NPK), and the other with both fertilization and straw returning (NPKS). For the paddy field soil, in addition to the RothC model, two modified versions, including RothC_p and RothC_0.6, were also selected for suitability evaluation. Three different model calibration methods were employed: the equilibrium method, parameter optimization method, and transfer function method, to analyze the impact of these calibration methods on model simulation performance. Normalized root mean square error (nRMSE), mean difference (MD), and the index of agreement (d) were selected as model evaluation metrics. 【Result】At the Heilongjiang station, organic carbon input exhibited a significant fluctuating trend, with the average annual carbon input under NPK and NPKS treatments being 1.71 and 3.52 t·hm-⊃2;, respectively. In contrast, organic carbon input at the 850 Farm was relatively stable, with the average annual carbon input for NPK and NPKS treatments being 1.89 and 5.90 t·hm-⊃2;, respectively. The simulation validation results from the Heilongjiang station showed that, under different model calibration methods, the nRMSE was consistently below 5%, and the index of agreement (d) ranged from 0.60 to 0.74. This indicated that the model performance was excellent across all calibration methods, and RothC was able to accurately simulate the SOC stock changes for both NPK and NPKS treatments in the dryland. When using the M2 method, the nRMSE for NPK and NPKS was the smallest, at 3.46% and 3.09%, respectively. The simulation validation results for the 850 Farm showed that the MD for RothC and RothC_p ranged from -1.47 to -13.41, with nRMSE values between 2.90% and 26.48% and d-values all below 0.1. This indicated that both models significantly overestimated the increase in SOC stocks and were unable to accurately simulate the changes in SOC stocks in the paddy field. For the RothC_0.6 model under the NPK treatment, the MD ranged from -0.08 to 0.44, with nRMSE values between 0.24% and 0.85% and d-values ranging from 0.31 to 0.76. Under the NPKS treatment, the MD ranged from -5.71 to -6.22, with nRMSE values between 11.21% and 12.12% and d-values between 0.12 and 0.13. These results indicated that RothC_0.6 could accurately simulate the dynamic changes in SOC stocks under the NPK treatment but significantly overestimate the changes in SOC stocks under the NPKS treatment.【Conclusion】RothC and RothC_0.6 were suitable for studying the dynamic changes in SOC stocks under dryland and paddy field conditions without straw returning in the Northeast region, respectively, and could accurately simulate the trends in SOC stocks. The impact of different model calibration methods on simulation performance was not significant. However, the transfer function method was simpler to compute, saved model running time, and provided better simulation performance. Therefore, this study recommended prioritizing the use of the transfer function method for model calibration.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    LIYunLi, DIAODengChao, LIUYaRui, SUNYuChen, MENGXiangYu, WUChenFang, WANGYu, WUJianHui, LIChunLian, ZENGQingDong, HANDeJun, ZHENGWeiJun
    Scientia Agricultura Sinica. 2025, 58(9): 1663-1683. https://doi.org/10.3864/j.issn.0578-1752.2025.09.001

    【Objective】 Wheat is a cornerstone of global food security, with its production being pivotal in both China and the international community. With global climate change, the threat of high temperature has become increasingly prominent, posing a significant challenge to wheat cultivation. The strategic identification and selection of heat-tolerant germplasm, coupled with the exploration of genes associated with heat resistance, are crucial steps. These efforts are essential for broadening the genetic diversity of heat tolerance in wheat within China, providing prerequisites for breeding heat-tolerant wheat varieties and ultimately contributing to the safeguarding of our nation’s food security in the face of a warming climate. 【Method】 In this study, a natural population of 331 wheat accessions was utilized, and artificial climate chambers were employed to simulate high temperatures conditions. The heat tolerance of wheat seedlings was assessed by monitoring their survival rate under various durations of treatment, using heat resistance grade as the evaluative metric. Meanwhile, a genome-wide association study (GWAS) was conducted using the 55K SNP chip to identify genetic loci associated with heat tolerance. Expression data from multiple tissues, including roots, leaves under heat stress were analyzed, leading to the selection of genes related to heat tolerance. Subsequently, qPCR validation of candidate genes was performed using the extremely heat-tolerant accession Xinong 889 and the heat-sensitive accession Chinese Spring (CS) as materials. 【Result】 Under high-temperature stress, significant variations in survival rates were observed among different wheat accessions. The extremely heat-tolerant, moderately heat-tolerant, moderately heat-sensitive, and extremely heat-sensitive germplasm accounted for 110, 104, 110, and 7, respectively, representing 33.23%, 31.42%, 33.23%, and 2.12% of the total. Heat-tolerant germplasms, including Xinong 889, Zhengmai 7698, Zhongmai 895, Zhoumai 18, and Fengchan 3, were identified. Through GWAS, a total of 293 SNP loci significantly associated with the 12-hour survival rates (SR) and heat resistance grades (HRG) were detected, with the phenotypic variation explained ranging from 4.40% to 12.46%. Among these, 200 loci were related to the 12-hour survival rates, and 257 were related to the heat resistance grades, with 164 loci identified as the same heat-related loci. Based on significantly associated SNP markers, 313 heat-related genes were predicted. According to gene annotation information and expression data under heat stress, 23 heat tolerance candidates were selected, and after qPCR validation of differentially expressed candidate’s genes, 20 key heat tolerance candidate genes were identified. 【Conclusion】 At the seedling stage, 331 wheat germplasms were identified for heat tolerance. A rapid method was developed for determining the survival rate of wheat seedlings subjected to treatments of varying durations at 45 ℃ to assess their heat tolerance In total, 38 heat-tolerant germplasms and 293 loci significantly associated with seedling heat tolerance were screened. Also, TraesCS1A02G355900, TraesCS1A02G389500, TraesCS5A02G550700, TraesCS5D02G557100, TraesCS6D02G402500 and TraesCS7A02G232500 represented as candidate genes were filtered out.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    YUERunQing, LIWenLan, DINGZhaoHua, MENGZhaoDong
    Scientia Agricultura Sinica. 2025, 58(7): 1269-1283. https://doi.org/10.3864/j.issn.0578-1752.2025.07.002

    【Objective】To clarify the molecular characteristics and the effectiveness of target traits of transgenic maize LD05 with composite insect and herbicide resistance, and to provide data basis, technical support and product reserve for industrial application.【Method】Using biological information analysis, we designed and modified the proprietary insect-resistant fusion gene m2cryAb-vip3A, and selected BC4F3, BC4F4 and BC4F5 generations of the newly created transgenic hybrid insect-resistant and herbicide-tolerant maize LD05 to carry out experimental research. Specific PCR and Southern blot were used to analyze the stability of genomic integration. qRT-PCR and ELISA were used to analyze the expression stability. The resistance to target pests was evaluated by bioassay and field trials, and the herbicide tolerance was tested by field spraying of glufosinate. 【Result】A new insect-resistant fusion gene m2cryAb-vip3A with independent property right was discovered and designed, and a multivalent insect-resistant and herbicide resistant maize transformant LD05 was created. The exogenous T-DNA was integrated into the maize genome in the form of a single copy. The qRT-PCR results indicated that m2cryAb-vip3A and bar were both expressed in various tissues and organs across three generations, and the variation trend of expression quantities was largely consistent. Specifically, the expression level of m2cryAb-vip3A was the highest in the leaves at the seedling stage of the three consecutive generations, with an average expression quantity of 36.73, while the expression level was the lowest in the cob at the mature stage, with an average of merely 0.91. The expression pattern of bar was similar to that of m2cryAb-vip3A, with the highest expression level in the leaves at the seedling stage, averaging 7.35, and the expression level decreased after the jointing stage. The ELISA results demonstrated that M2CryAb-VIP3A could stably accumulate in different organs and at different periods in the three generations, and the protein accumulation amounts in different generations were similar. Among them, the accumulation amount was the highest in the leaves at the seedling stage of different generations, all exceeding 19.67 μg·g-1 fresh weight. The expression of the targeted protein at a relatively high level could be detected in different tissues of the PAT transgenic plants of three consecutive generations, and there was no significant difference in the expression quantity between different generations. Among them, the expression level was the highest in the leaves at the seedling stage of different generations, with an average content of 16.61 μg·g-1 fresh weight, while the accumulation amount was the lowest in the roots at the mature stage, with an average content of 0.30 μg·g-1 fresh weight. The bioassay result showed that the corrected mortality of Ostrinia furnacalis, Spodoptera fragiperda and Mythimna separata reached 100% after feeding on V5 maize leaf tissue of LD05 for 96 h, which was a high resistance level. The results of field trials showed that LD05 transformants had high resistance to Ostrinia furnacalis at V5 stage and silking stage, to Mythimna separata at V5 stage, and to Helicoverpa armigera at silking stage. The results of glufosinate tolerance test showed that transgenic maize LD05 could tolerate 4-fold glufosinate. Agronomic character investigation showed that there was no difference between transgenic maize LD05 and control maize Zheng 58.【Conclusion】A novel insect-resistant fusion gene m2cryAb-vip3A with independent property rights was developed, and a transgenic hybrid insect-resistant and herbicide-tolerant maize LD05 was created with clear molecular characteristics, genetic stability and outstanding functional traits.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    DENGLiCheng, LICheng, HELei, ANHongQiang, WANGCaiLin, ZHANGYaDong, ZHAOChangJiang, LUKai
    Scientia Agricultura Sinica. 2025, 58(12): 2275-2290. https://doi.org/10.3864/j.issn.0578-1752.2025.12.001

    【Objective】Salt stress is one of the main environmental stresses that restrict rice production. Studying the physiological characteristics under salt stress and analysis the allelic variation and expression of salt-tolerance genes provide key gene resources and genetic materials for breeding salt-tolerance rice varieties. 【Method】This study first evaluated the salt-tolerance ability of the Nangeng series high-quality rice varieties/lines during the seedling stage, using survival rate as an indicator for screening salt-tolerance varieties, which physiological changes under salt stress were analyzed, including chlorophyll, Na+, K+, MDA, H2O2 and soluble sugar. The variation types and expression levels of salt-tolerance genes in rice varieties with resistance to high salt concentration were also analyzed to explaining their molecular mechanisms in response to salt stress. 【Result】Under the condition of treating with 140 mmol·L-1 NaCl for 6 days, the survival rates of NG9108, NG5718, and NGY1 were greater than 60%, with the highest survival rate among the tested varieties. Compared with Nipponbare, the seedlings of NG9108, NG5718, and NGY1 under salt stress had higher chlorophyll content and lower MDA content, indicating that salt stress caused less cell damage to the three varieties. The Na+/K+ values in the roots of NG9108, NG5718, and NGY1 were significantly higher than those in Nipponbare, while the Na+/K+ values in the aerial parts were significantly lower than those in Nipponbare, implying that the three varieties absorb or store more Na+ in roots, but transport less Na+ upwards, which is beneficial for maintaining cell ion balance and causing less ion toxicity and osmotic stress in aerial parts of the seedlings. The three salt-tolerance varieties have 94 SNPs or InDel sites, distributing in exons, introns, 5′UTR, and 3′UTR of the 23 salt-tolerance genes. 24 variation sites of 11 genes occur in the exons, including 7 genes with frameshift mutations or missense mutations which distributed in Os02g0813500 (OsGR2), Os05g0343400 (OsWRKY53), Os06g0685700 (OsRST1), Os07g0685700 (OsEIL2), Os10g0431000 (OsPQT3), Os11g044600 (OsRSS3), Os12g0150200 (P450). Salt stress significantly induces expression of OsSKC1, OsBAG4, OsGPX1, OsCCX2, OsGR3, OsDREB2a, OsRAB21, OsP5CS, OsbZIP23, OsAPX37 and OsLEA3, which help to enhance salt tolerance and reduce the adverse effects of salt damage on rice growth. 【Conclusion】NG9108, NG5718 and NGY1 showed strong salt tolerance phenotype during the seedling growth stage, which is closely related to the balance of sodium and potassium ions under salt stress, allelic variations of multiple salt tolerance genes, and gene expression levels. NG9108, NG5718 and NGY1 have pyramided multiple salt tolerant and high-quality genes, which can be used as backbone parents for genetic improvement and breeding.

  • SOIL & FERTILIZER·WATER-SAVING IRRIGATION·AGROECOLOGY & ENVIRONMENT
    LUO YuHong, HUANG YuShu, ZHU Na, LI Le, CHENG YanBin, LIU JiaHui, ZHANG JingMin, BAO YuFan, XU Nuo, YAN YuChun
    Scientia Agricultura Sinica. 2024, 57(24): 4919-4932. https://doi.org/10.3864/j.issn.0578-1752.2024.24.008

    【Objective】This study aimed to explore the dynamic change of soil texture and nutrients resulting from 60 years of agricultural cultivation subsequent to the conversion of grassland to cropland in the typical steppe of Xilingol County. It also evaluated whether the 18 years cropland afforestation had effectively mitigated the negative impacts of long-term cultivation on soil particle size distribution and soil nutrients. The research sought to enhance understanding of soil quality evolution during ecological restoration processes in this region and provided a scientific basis for assessing the actual effectiveness of ecological restoration measures. 【Method】Five sites within 60 km2 of the study area as replicates were chosen to investigate the particle size distribution, bulk density, and nutrient characteristics within the 0-30 cm soil layer across four land use types, including grassland (GL), cropland (CL) and afforestation land with row spacing of 2 m (AL-2) and 5 m (AL-5). 【Result】(1) The soil particle composition across various land use types included sand (61%-82%), silt (16%-35%) and clay (less than 4%). Notably, the content of silt (2-50 μm) in cropland and afforestation land was significantly lower than that in grassland, whereas the proportion of sand (>50 μm) was markedly higher in comparison to grassland. Further, compared with natural grassland, the cultivation has resulted in a reduction of soil particles smaller than 120 μm and an increase in soil particles larger than 120 μm. However, the afforestation for 18 years has not alleviated the decrease in fine particles (≤120 μm) caused by cultivation. (2) In 0-30 cm soil layer, the composition of soil particle size in each land use type showed uniformity along the soil depth, which reflected poor sorting characteristics and a negative to extremely negative particle size distribution pattern and sharp kurtosis. Among them, the grassland had the smallest mean particle size and the highest fractal dimension. (3) The soil bulk density gradually increased with the increase in soil depth. Nutrient changes were primarily concentrated in the shallow soil layer of 0-10 cm, where cultivation activities led to significantly decrease in soil organic carbon (OC), total nitrogen (TN) and total phosphorus (TP) content. Compared with cropland, the shrubland formed after afforestation did not significantly alter the content of organic carbon and total nitrogen, but significantly reduced the total phosphorus content. (4) It A highly significant positive correlation between soil particle components smaller than 120 μm and soil organic carbon, total nitrogen and total phosphorus was found, which indicated that the decline in soil nutrients was closely linked to the loss of fine soil particles. 【Conclusion】In summary, the long-term conversion of grassland to cropland has led to the degradation of soil physical structure, with the loss of soil fine particles has affected the enrichment of nutrients. Moreover, the effects of afforestation after 18 years on improving soil texture and restoring nutrient levels were not significant.

  • SOIL & FERTILIZER·WATER-SAVING IRRIGATION·AGROECOLOGY & ENVIRONMENT
    HUDanDan, SONGHuiJie, DUANYingHua, WUYan, HUZhiHhua, XUXiaoLin, ZHANGWenJu, HEXiaoLin, LIUKaiLou, SUPeng, HUANGQunZhao
    Scientia Agricultura Sinica. 2024, 57(24): 4907-4918. https://doi.org/10.3864/j.issn.0578-1752.2024.24.007

    【Objective】The analysis of rice yield, nitrogen use efficiency and the quantitative relationship between apparent nitrogen balance and soil alkali-hydrolyzed nitrogen under different nitrogen fertilizer management conditions could provide a more comprehensive understanding of the effects of long-term fertilization on soil fertility, so as to provide the theoretical guidance for efficient production and scientific nitrogen management of red soil paddy fields. 【Method】Based on the red soil double cropping rice long-term fertilization positioning experiment (started in 1981, located in Jinxian County, Jiangxi Province), five treatments were selected: no fertilizer (CK), nitrogen and phosphorus fertilizer (NP), nitrogen and potassium fertilizer (NK), nitrogen, phosphorus and potassium fertilizer (NPK), nitrogen, phosphorus and organic fertilizer (NPKM), and then the grain and straw yield and nitrogen uptake of rice in each season were investigated and analyzed, and the soil alkali-hydrolyzed nitrogen content was analyzed after late rice. The nitrogen uptake, nitrogen utilization rate, nitrogen apparent balance and the changes of soil alkali-hydrolyzed nitrogen were calculated and analyzed on a 10-year basis. 【Result】During the 40 years of experiment (1981-2020), the rice yield and nitrogen uptake under NPKM treatment were the highest, increased by 65.9%-108.4% and 85.1%-132.5% compared with CK, respectively, and increased by 19.3%-92.1% and 19.4%-99.8% compared with fertilizer treatments (NPK, NK and NP), respectively, showing significant differences. With the increase of the experimental period, the nitrogen use efficiency of fertilizer treatment gradually decreased, and the NPKM treatment also showed a decreasing trend in the first 30 years (1981-2010), but the rate was slower than that of fertilizer treatment, and increased in the recent 10 years (2011-2020), and from the lowest in the first 10 years (1981-1990) to the highest in the recent 10 years, increased by 25.3%-271.2% compared with fertilizer treatment. The nitrogen surplus was the highest under NPKM treatment during the 40 years of experiment, with an increase of 137.1%-577.2% compared with fertilizer treatment, but in the last 30 years (1991-2020), the nitrogen surplus gradually decreased with the increase of the experimental period. The soil alkaline hydrolyzed nitrogen content was the highest under NPKM treatment during the 40 years of experiment, increased by 7.1%-24.4% compared with CK, but the difference was not significant in the first 10 years, and increased by 11.0%-35.2% compared with fertilizer treatment, while there was no significant difference between fertilizer treatment and CK. Correlation analysis showed that the nitrogen surplus was significantly positively correlated with the soil alkaline hydrolyzed nitrogen content in the last 20 years (2001-2020). 【Conclusion】In the red soil double-cropping rice system, with the increase of fertilization years, the combined application of organic and inorganic fertilizers had better effects on rice yield, nitrogen uptake, nitrogen uptake and utilization, and soil alkali-hydrolyzed nitrogen content. Meanwhile, the increase of nitrogen surplus caused by long-term fertilization also further increased the soil alkali-hydrolyzed nitrogen content in the topsoil. The contribution capacity of nitrogen surplus to soil alkali-hydrolyzed nitrogen increased gradually.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    WANGHui, DINGBaoPeng, LIYuXian, RENQuanRu, ZHOUHai, ZHAOJunLiang, HUHaiFei
    Scientia Agricultura Sinica. 2025, 58(11): 2045-2061. https://doi.org/10.3864/j.issn.0578-1752.2025.11.001

    The global population continues to rise and climate change imposes severe challenges on food supply, the issue of food security has become increasingly prominent. To meet the growing demand for food, enhancing crop yield and improving environmental adaptability have become critical goals in agriculture. Under this situation, genomics is regarded as an essential method for accelerating crop breeding, as it enables the in-depth exploration and utilization of superior functional genes to not only boost crop productivity but also strengthen stress tolerance and adaptability, thereby providing robust support for ensuring global food security and achieving sustainable agricultural development. Nonetheless, the traditional single-reference genome often fails to capture the entire spectrum of genomic variations accumulated during crop domestication and improvement, which constrains our understanding of functional genes and their regulatory networks. With the continual advancement of high-throughput sequencing technologies, genomics research has now entered the pangenomics era. By integrating multiple high-quality genomes into a comprehensive catalog of genomic content, researchers can precisely identify a variety of genetic variations, including single nucleotide polymorphisms (SNPs) and structural variations (SVs), thereby capturing the extensive genetic diversity present across different cultivars, subspecies, and wild relatives. Pangenomics framework greatly facilitates the exploration of superior functional genes. Moreover, by combining pangenomic data with other multi-omics datasets (e.g., transcriptomics, proteomics, and epigenomics), researchers can accurately identify superior functional genes, enabling the provision of more targeted and accurate genetic loci for molecular breeding. With emerging gene-editing tools such as CRISPR-Cas9, researchers can further modify essential genetic loci in a directed manner to remove undesirable traits or reinforce resistance to environmental stressors. This will lay a foundation for cultivating the next generation of crops that exhibit higher yield, improved quality, and enhanced resilience. This review summarizes recent developments in major pangenome construction methods and formats, and systematically reviews the progress made in crop pangenomes as well as their applications in crop breeding improvement. It also discusses the challenges pangenomics faces in future crop breeding, offering insights into leveraging pangenome resources for crop genetic improvement, and ultimately provides new perspectives and strategies for future molecular breeding.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    LIUDeLong, LIShiRu, WANGChuanXing, GUOShuQing, MAZhiXiu, WUYongJiang, HANHuiBing, LIYuJie, ZHANGPanPan, YANGPu
    Scientia Agricultura Sinica. 2024, 57(18): 3533-3550. https://doi.org/10.3864/j.issn.0578-1752.2024.18.003

    【Objective】 Plant height is a trait that plays an important role in the increase of foxtail millet yield. The dynamic changes of foxtail millet plant height at different growth stages were studied, and the QTL loci and effects controlling plant height were identified to provide a theoretical basis for plant type breeding of foxtail millet. 【Method】 In this study, a recombinant inbred line population YRRIL containing 215 lines were used as the research object, and the YRRIL population was planted in two environments, Yulin, Shaanxi and Mizhi, Shaanxi, in May 2023, respectively. The phenotypic values of plant height trait of each family were measured at five stages: seedling, elongation, booting, tasseling, and ripening period, respectively. Combined with the genetic linkage map of the YRRIL population, genetic analysis and dynamic QTL mapping of plant height trait at different growth stages of millet were carried out, and the unconditional QTL and conditional QTL controlling plant height of millet were identified. On this basis, candidate gene prediction for important QTL was carried out using Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis methods. 【Result】 In the entire growth period of the millet plant height growth trend was the “S” type curve, from the elongation stage to the booting stage, the growth rate of plant height was faster, which was the key stage of plant height development. In the two environments, plant height of each family line of the population showed continuous distribution at different periods. A total of 86 QTL related to plant height were detected at five periods in the two environments, which were distributed on all 9 chromosomes of the foxtail millet genome. It contained 48 unconditional QTL and 38 conditional QTL, and the phenotypic contribution rate of unconditional QTL was 1.13%-17.49%, of which 6 could be detected repeatedly at two growth periods, and the rest were detected only at one growth period. The phenotypic contribution rate of conditional QTL was 1.97%-14.69%, of which one could be detected repeatedly at two growth stages, and the rest were detected only at one growth stage. No QTL that can be detected in three or more periods were present in either unconditional QTL analysis or conditional QTL analysis. A total of 12 major QTL were detected by unconditional QTL and conditional QTL analysis in two environments, of which 6 QTL were newly identified as primary loci in this study. Based on the prediction and analysis of genes within the main effect QTL interval combined with functional annotation of homologous genes screened out 14 candidate genes that might be related to foxtail millet plant height, among which Seita.1G242300.1, Seita.6G110200.1, and Seita.7G143300.1 were all able to directly regulate plant height development. 【Conclusion】 In the two environments, a large number of QTL were detected to be involved in the phenotypic regulation of plant height trait during the whole growth and development of foxtail millet, with 79 (91.86%) played a role in one period and 7 (8.14%) played a role in two periods and there were no QTL detected in three or more periods, including 12 major QTL. The QTL detected by unconditional and conditional analysis methods accounted for 55.81% and 44.19%, respectively, and 16 (18.60%) were both unconditional and conditional QTL. The QTL effects controlling plant height development at different stages varied, with smaller effect in the seedling stage and generally larger effects from the elongation to the tasseling stage.

  • PLANT PROTECTION
    LIChuXin, SONGChenHu, ZHOUJinHuan, LIJiaXin, WANGXinLiang, TIANXuBin, SONGZhen
    Scientia Agricultura Sinica. 2024, 57(22): 4473-4482. https://doi.org/10.3864/j.issn.0578-1752.2024.22.007

    【Objective】Citrus yellow vein clearing virus (CYVCV) is a novel virus that poses a significant threat to the citrus industry. Currently, there is no effective therapeutic agent. The primary strategies for prevention and management involve utilizing virus-free seedlings and implementing stringent control measures against insect vectors. The objective of this study is to investigate the technology of virus-induced gene silencing (VIGS) as a means of developing antiviral “vaccines” for CYVCV, and to offer innovative approaches for the prevention and management of citrus viral diseases.【Method】Based on the previously constructed VIGS vector pCLBV201 in the laboratory, a series of recombinant vectors were designed and developed to target the conserved regions of the CYVCV genome, specifically open reading frame 1 (ORF1), open reading frame 6 (ORF6), coat protein (CP), and triple gene block (TGB). Agrobacterium-mediated vacuum infiltration was inoculated on Eureka lemon, followed by RT-PCR detection. After acquiring several positive plants including pCLBV201-ORF1, pCLBV201-ORF6, pCLBV201-CP, and pCLBV201-TGB, CYVCV infectious clones were inoculated via Agrobacterium-mediated injection, with plants infiltrated with the pCLBV201 empty vector serving as controls. Subsequent RT-qPCR, Western blot analysis, symptom observation, and disease index statistics were conducted to elucidate the preventive and control effects of the various VIGS recombinant vectors on CYVCV. 【Result】A series of recombinant vectors of pCLBV201 were constructed, and the results of RT-PCR following inoculation indicated that multiple positive plants for pCLBV201-ORF1, pCLBV201-ORF6, pCLBV201-CP, and pCLBV201-TGB were obtained, respectively. CYVCV infectious clones were inoculated by injection. The results of RT-qPCR at 7, 14, 28, 70, and 150 dpi (days post infection) showed that the relative expression of CYVCV in the pCLBV201-CP and pCLBV201-TGB treatment groups was significantly lower than that in the control group. Western blot analyses conducted at 70 and 150 dpi showed a significant decrease in the expression of CP protein in the pCLBV201-CP and pCLBV201-TGB treatment groups. Observational symptoms indicated that the control group exhibited typical manifestations of CYVCV infection, such as severe vein clearing and leaf distortion, whereas the pCLBV201-CP treatment group displayed mild symptoms, and the pCLBV201-TGB treatment group showed no apparent symptoms. The disease index statistics at 70 and 150 dpi demonstrated that the disease indices of pCLBV201-CP and pCLBV201-TGB were the lowest, recorded at 17.6, 41.2 and 15.6, 29.1, respectively, while the control group had indices of 52.1 and 80.0, showing obvious differences.【Conclusion】The VIGS-based technology for the prevention and control of CYVCV was developed, which clarified that pCLBV201-CP and pCLBV201-TGB could significantly reduce the virus titers and alleviate the symptoms caused by the virus. They have the potential to be used as “vaccines” for CYVCV prevention and control.

  • TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY
    FENGYingMing, NONGWei, CHENXingYun, HANHongXiang, ZHENGYuXin, TIANXiao, TANGJiao, GUOYiWei, HUANGChaoZheng, LIXueWen, SHILei, YUMin
    Scientia Agricultura Sinica. 2024, 57(24): 4871-4883. https://doi.org/10.3864/j.issn.0578-1752.2024.24.004

    【Objective】This study aimed to explore the physiological mechanism of silicon alleviating aluminum toxicity in plants, to study the effect of biomineralization structure constructed on rice root border cells and root tips on aluminum stress, so as to provide the theoretical and practical guidance for acid soil mineralization to alleviate aluminum toxicity of plants in southern China. 【Method】Employing rice (Oryza.Sativa L.) as the experimental materials, using root tips and root border cells as the research object, under 100 μmol·L-1 aluminum stress treatment, polyethylenimine induced nano silica to form biomineralization structure on the surface of root tips and root border cells. Four treatments are administered: bare cells without aluminum stress (-Si-Al), bare cells with aluminum stress (-Si+Al), silica-coated cells without aluminum stress (+Si-Al), and silica-coated cells with aluminum stress (+Si+Al). The study examined the cell viability, levels of active oxygen species, and localization of active aluminum in root border cells, as well as the relative elongation of the root tips, levels of active oxygen species, callose content and localization of active aluminum in the root tips. 【Result】Under aluminum stress, compared with non biomineralization, polyethylenimine induced nano silica deposition on the cell wall of root border cells, so the survival rate of root border cells increased by 21.04%, the level of reactive oxygen species decreased by 87.65%, and the relative fluorescence value increased by 77.09% after Morin staining, and then effectively improved cell survival rate, reduced ROS production, and slowed down the programmed cell death; after polyethylenimine induced nano silica deposition in root tip, the relative growth rate of root tip increased by 26.95%, the level of reactive oxygen species decreased by 27.73%, the content of callose increased by 55.29%, and the relative fluorescence value increased by 55.45% after Morin staining, hematoxylin staining also showed that more Al3+ was deposited in the meristematic and transitional zones of root tip, and this indicated that the biomineralization deposition could adsorb more Al3+ on the surface of root tip, prevent Al3+ from entering the root tip to protect, and then alleviate the toxic effect of aluminum on root tip. 【Conclusion】Polyethylenimine induced nano silica deposition on the cell wall endows rice root border cells and root tips with aluminum tolerance, and reduced aluminum accumulation in rice, thus ensuring food safety and human health.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    ZHAOYong, AIJing, WANGYuTong, ZHANGZhongFu, YANGHongQi, LIJiaQun, GUOZhaoJian, LIUHaiJun, QINWei, DENGJun, ZHANGYueBin
    Scientia Agricultura Sinica. 2024, 57(19): 3743-3757. https://doi.org/10.3864/j.issn.0578-1752.2024.19.003

    【Objective】The research focused on the production potential of sugarcane main varieties under the different planting modes in mountainous and hilly regions, in order to explore the relationship between the varieties and mechanical adaptation, screen the adaptable varieties for mechanical production, and clarify the main characteristics of the varieties, thus to provide the theory for promoting the completely mechanical production of sugarcane in mountainous and hilly regions.【Method】Two different ecological types of sugarcane production regions in mountainous regions of Yunnan were selected to study the production potential of four main planting varieties, including LC05-136, YZ05-49, YZ05-51, and YZ08-1609, under two different planting modes (the completely mechanical or manual production).【Result】The yield and sucrose content of sugarcane varied between the two factors of varieties and planting modes, and the yield was significantly affected. Under the mechanical production, the yield of YZ08-1609 was significantly higher than that with the treatment of artificial production (P<0.01), while YZ05-51 showed the opposite trend (P<0.01), under the mechanical production, the sucrose content of YZ08-1609 is slightly higher than that with the artificial production (P>0.05), while these of LC05-136 and YZ05-49 were slightly decreased (P>0.05). The planting density and the emergence rate of sugarcane varied with both varieties and production modes. The planting density under the machinery production was generally higher than that under the artificial production, while the emergence rate was generally lower than that with the treatment of the artificial production. The emergence rate of YZ05-51 under the machinery production significantly decreased (P<0.05), while the emergence rate of YZ08-1609 remained relatively stable (P>0.05). The main agronomic traits of sugarcanes varied with both varieties and the production modes. The millable stalks of YZ08-1609 under the machinery production were significantly higher than that under the artificial production (P<0.05); the industrial characteristics were mainly influenced by the variety. YZ08-1609 owned higher growth potential under the machinery production, with significantly higher yield and millable stalks compared with these under the artificial production, and slightly higher sucrose content; YZ05-51 owned higher growth potential under the artificial production with the performance of higher yield under the artificial production. 【Conclusion】Different sugarcane varieties owned the different adaptabilities to the machinery production, like some sugarcane varieties were suitable for the machinery production and some were suitable for the manual production. During pushing forward the progress of the application of mechanical production in sugarcane planting, the adaptability of varieties should be fully considered. Overall, sugarcane varieties suitable for the machinery production should own higher sugarcane yield and more millable stalks, and the sucrose content should be less affected or even slightly higher than that under the manual production.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    DUYanWei, YANXiaoGuang, ZHAOJinFeng, JIASuQing, WANGGaoHong, YUAiLi, ZHANGPeng
    Scientia Agricultura Sinica. 2024, 57(22): 4416-4430. https://doi.org/10.3864/j.issn.0578-1752.2024.22.003

    【Objective】The Ca2+-CBL-CIPK signaling pathway has important functions in plant response to abiotic stresses. By cloning the SiCIPK21 gene and studying its function under stress conditions, we provide a key candidate gene and theoretical basis for molecular breeding of foxtail millet with stress tolerance.【Method】Bioinformatics was used to analyze the cis-acting elements in the promoter region of this gene and predict the interactions between this protein and AtCBLs in Arabidopsis thaliana. SiCIPK21 was cloned by PCR, and a fusion expression vector was constructed for transient expression in tobacco to determine the subcellular localization. foxtail millet cv. Yugu 1 was used as material, and specifically amplified part of the SiCIPK21 gene fragment from Yugu 1 leaves, and recombinant vector VIGS-pTRV2-SiCIPK21 was constructed, using the phytoene desaturase gene (SiPDS) as the indicator gene, and seedlings of foxtail millet at the two-leaf stage were selected and infiltrated by cotyledon injection to investigate the role of SiCIPK21 under salt stress (250 mmol·L-1 NaCl) by using virus-induced gene silencing (VIGS) technology. T3 generation transgenic lines were obtained by overexpressing SiCIPK21 in Arabidopsis thaliana. Phenotypes at germination were analyzed under different concentrations of NaCl (150/175 mmol·L-1), mannitol (300/400 mmol·L-1) and ABA (0.25/0.5 μmol·L-1) treatments, and salt and drought tolerant phenotypes at seedling stage were also analyzed.【Result】Subcellular localization revealed that SiCIPK21 was located in the nucleus. The protein SiCIPK21 might interact with AtCBL2, AtCBL3, AtCBL4, AtCBL9, and AtCBL10 in Arabidopsis thaliana. The promoter region of SiCIPK21 contained adverse response elements, suggesting that SiCIPK21 may participate in the adverse responses. The VIGS gene silencing demonstrated that SiCIPK21-silenced foxtail millet plants had increased sensitivity to salt stress than the control plants. Three independent T3 generation Arabidopsis thaliana overexpression lines (2#, 3# and 6#) were obtained by genetic transformation. Overexpression lines showed significantly higher germination rate, germination speed, green cotyledon unfolding rate, root length and fresh weight than the wild-type plants (WT) at different concentrations of NaCl (150/175 mmol·L-1), mannitol (300/400 mmol·L-1) and ABA (0.25/0.5 μmol·L-1). Moreover, phenotypic analysis of salt and drought tolerance in Arabidopsis seedlings showed that overexpression lines had significantly higher survival rates and chlorophyll contents than WT.【Conclusion】SiCIPK21 is a positive regulator of plant response to salt and drought stresses, which makes it a candidate gene for improving stress tolerance by molecular breeding in foxtail millet.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    LÜTao, SUNGuoQing, GUODongCai, CHENQuanJia, CAIYongSheng, FANBiaoXing, QUYanYing, ZHENGKai
    Scientia Agricultura Sinica. 2025, 58(9): 1684-1701. https://doi.org/10.3864/j.issn.0578-1752.2025.09.002

    【Objective】 The objective of this study is to develop InDel molecular markers for Island cotton, which is characterized by its superior fiber quality, particularly the fiber tensile strength-a key indicator of cotton fiber quality. The study aims to validate these markers using RIL (Recombinant Inbred Line) populations and resource materials, thereby providing a theoretical foundation for breeding new varieties of Island cotton with enhanced fiber quality. 【Method】 Utilizing a previously established population of 213 Pima S-7 and 5917 F5:6 RILs, we conducted QTL (Quantitative Trait Locus) mapping to identify the locus regulating fiber strength in Island cotton, designated qFS-chr17-1. InDel markers were designed based on whole genome sequencing (WGS) data of the parental lines, followed by the identification of polymorphic markers. Preliminary validation of these markers was performed using 40 extreme family materials selected based on phenotypic data. Genotyping was carried out on both the 213 RIL population and the 213 Island cotton resource population, alongside multi-year fiber quality data to assess the markers' effectiveness. 【Result】 The genotyping of the RIL and Island cotton resource populations with the two developed InDel markers indicated a close linkage to fiber strength phenotypic data, with significant differences observed in fiber strength traits among the differentiated materials. The analysis of genotypic combinations revealed an upward trend in fiber strength across four combination types, with materials exhibiting the Hap3 (B/A) and Hap4 (B/B) genotypes demonstrating significantly greater fiber strength than those with Hap1 (A/A) and Hap2 (A/B). Furthermore, the InDel-3L2 marker showed significant correlations with fiber length, fiber uniformity, and spinning consistency index, consistent with the observed phenotypic trends. Analysis of multi-year fiber quality data from two experimental sites revealed environmental variability in fiber quality, while temperature data indicated that the developed molecular markers are minimally influenced by environmental factors. Clustering analysis of fiber quality data from 213 Island cotton resource materials, combined with molecular marker genotyping, identified eight materials exhibiting superior fiber quality. 【Conclusion】 This study successfully developed two InDel molecular markers closely linked to the fiber strength QTL (qFS-chr17-1), which maintain their effectiveness upon combination. The InDel-3L2 marker demonstrates significant correlations with fiber length, fiber uniformity, and spinning consistency index. These markers can efficiently and accurately identify high-strength fiber resources in Island cotton, contributing to the breeding of improved fiber quality. Additionally, eight materials with excellent fiber quality have been identified.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    XIONGJiaNi, LIZongYue, HUHengLiang, GUTianYu, GAOYan, PENGJiaShi
    Scientia Agricultura Sinica. 2025, 58(7): 1259-1268. https://doi.org/10.3864/j.issn.0578-1752.2025.07.001

    【Objective】Cadmium (Cd) is the predominant pollutant in China’s arable land, with rice cultivated on these contaminated soils being a significant dietary source of Cd for the population. This study aims to tissue-specifically express OsNRAMP5, a transporter responsible for the majority of Cd uptake in rice, to investigate strategies for developing low-Cd rice varieties and provide a reference for molecular design breeding to cope with Cd pollution. 【Method】To drive the expression of OsNRAMP5 in rice, we utilized a 2 500 bp sequence upstream of the OsLCT1 start codon as the promoter. The red fluorescent protein mRFP was fused to the C-terminus of OsNRAMP5 to visualize its tissue localization. After obtaining independent homozygous transgenic lines, the transcripts of the OsNRAMP5 were first detected using qRT-PCR, and its tissue localization in roots and nodes was observed via laser confocal microscopy. Subsequently, the accumulation and tolerance of Cd were evaluated in transgenic and wild-type rice under varying concentrations of Cd treatment. Furthermore, plants were grown in Cd-contaminated paddy soil, and the accumulation of Cd and other mineral elements in seeds and leaves, as well as related yield traits, were measured. 【Result】Under the drive of the OsLCT1 promoter, OsNRAMP5 was expressed mainly in the epidermis, exodermis and stele of roots, as well as in the phloem area of enlarged vascular bundles and diffuse vascular bundles in nodes, differing significantly from the native expression pattern of OsNRAMP5 in rice. Compared to wild-type rice, the transgenic lines exhibited increased Cd accumulation in roots, decreased Cd accumulation in shoots, and enhanced tolerance to Cd stress during the seedling stage. When cultivated in Cd-contaminated paddy soils, plant height and grain yield were unaffected by the ectopic expression of OsNRAMP5, while Cd accumulation in seeds and leaves significantly decreased in the transgenic lines. The Cd content in seeds decreased by over 80%, with a greater reduction ratio compared to that in leaves. Although the Mn content in seeds and leaves slightly decreased, the expression of OsNRAMP5 had little impact on the accumulation of other mineral elements such as Fe, Zn, and Cu. 【Conclusion】The expression of OsNRAMP5 driven by the OsLCT1 promoter greatly decreases the Cd migration toward rice seeds by reducing Cd transport to the aboveground parts from roots and increasing the Cd transporting to leaves at nodes. Therefore, the expression of OsNRAMP5 under the control of the OsLCT1 promoter is an effective strategy to reduce Cd accumulation in rice seeds.

  • CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS
    ZENGXiangCui, YANGYongNian, LIRuYue, JIANGXueQian, JIANGXu, XUYanRan, LIUZhongKuan, LONGRuiCai, KANGJunMei, YANGQingChuan, LIMingNa
    Scientia Agricultura Sinica. 2024, 57(24): 4839-4853. https://doi.org/10.3864/j.issn.0578-1752.2024.24.002

    【Objective】CEP (C-terminal encoded peptides) is a gene that encodes hormone-like peptides secreted by roots and serves as a key regulator of plant root growth and development. To provide a molecular theoretical basis for further elucidating the function of MsCEP genes in root growth and development, members of the Medicago sativa MsCEP gene family, basic characteristics, expression differences in different tissues, and their roles in root growth were identified and analyzed. 【Method】Based on the genomic information of the alfalfa cultivar Xinjiang Daye, the MsCEP gene family members of alfalfa were accurately identified using local Blast analysis in TBtools and feature domain by referring to MtCEP family protein of Medicago truncatula sequence. The fundamental genetic and protein characteristics and the phylogenetic relationship of the MsCEP genes were analyzed by bioinformatics methods. The expression patterns of alfalfa MsCEP gene family members in various tissues were assessed using transcriptome data and real-time fluorescence quantitative PCR. The functional roles of mature MsCEP peptides in root growth and development were analyzed by exogenous application experiments. 【Result】A total of 35 MsCEP family members were identified in the genome of alfalfa Xinjiang Daye, and these genes are distributed across 18 chromosomes, lack introns, and all possess an N-terminal signal peptide and one or two conserved domains of the CEP family. The MsCEP members displayed predicted amino acid length ranging from 59 to 150, with molecular weights spanning 6.7 to 16.2 kDa, the isoelectric points varying from 5.80 to 10.41, instability indices ranging from 30.63 to 89.93, aliphatic indices ranging from 54.41 to 134.88, and the grand average of hydropathicity ranging from -1.110 to 0.377. Subcellular localization predictions indicated that the MsCEP protein predominantly localizes to the nucleus, plasma membrane, chloroplast, and Golgi apparatus. Cluster analysis delineated three distinct branches within the family, aligning with counterparts from Arabidopsis thaliana and Medicago truncatula. The largest branch encompassed 48 CEP members. Collinearity analysis highlighted a collinear relationship between the MsCEP genes in alfalfa and those in Arabidopsis thaliana and Medicago truncatula. Tissue expression analysis revealed that members of the MsCEP family exhibit distinct tissue-specific expression patterns, with higher expression levels in roots and lower or no expression detected in leaves. Among them, 22 members exhibited higher expression levels in roots compared to other tissues. The exogenous application of synthetic mature MsCEP2 peptide suppressed the growth of primary and lateral roots, reduced the number of lateral roots, and decreased the density of lateral roots. 【Conclusion】In conclusion, our investigation identified a total of 35 MsCEP members from the alfalfa 'Xinjiangdaye' genome database, which are revealed to be highly conserved. The MsCEP genes are primarily expressed in roots, and the exogenous application of synthetic mature MsCEP peptides can regulate root morphology, indicating that MsCEP peptides play important roles in root growth and development of alfalfa.

  • PLANT PROTECTION
    CONGQiQi, ZHANGJingYi, MENGXiangLong, DAIPengBo, LIBo, HUTongLe, WANGShuTong, CAOKeQiang, WANGYaNan
    Scientia Agricultura Sinica. 2025, 58(3): 478-492. https://doi.org/10.3864/j.issn.0578-1752.2025.03.006

    【Objective】Apple ring rot is one of the serious fungal diseases in apple production caused by Botryosphaeria dothidea. The aim of this study is to obtain strains of B. dothidea with weak pathogenicity carrying dsRNA viruses, identify the types of viruses, and clarify the distribution of these viruses in China, so as to provide new biological control resources for the prevention and control of apple ring rot and new insights into the diversity and systematic evolution of fungal viruses. 【Method】Samples of branches with typical symptoms of apple ring rot were collected from across China, and pure cultures were obtained through tissue isolation and single-spore isolation. Virus-carrying strains were identified through dsRNA band analysis, and the types of dsRNA viruses carried by the virus-carrying strain WH-2L were identified using high-throughput sequencing and molecular cloning techniques. The presence of two types of dsRNA viruses in B. dothidea from six provinces (autonomous region) in China was determined by RT-PCR. Pathogenicity differences among representative strains carrying different viruses were clarified through pathogenicity tests. Finally, the transmission characteristics of the two viruses were revealed through analysis of vertical and horizontal transmission properties. 【Result】For the first time in apple-producing regions of China, strains of B. dothidea causing apple ring rot were found to be co-infected with two viruses: Botryosphaeria dothidea chrysovirus 1 (BdCV1), belonging to the family Chrysoviridae and genus Chrysovirus, and Botryosphaeria dothidea victorivirus 2 (BdVV2), belonging to the family Totiviridae and genus Victorivirus. It was clarified that BdCV1 and BdVV2 are widely distributed in B. dothidea causing apple ring rot in China. BdCV1 was detected in strains from Liaoning, Shandong, Henan, Hebei, Shaanxi, and Xinjiang, except for Yan’an in Shaanxi and Shijiazhuang in Hebei, with an average detection rate of 53.6%. BdVV2 occurred in Liaoning, Shandong, Henan, Hebei, and Shaanxi, but was not detected in Yan’an in Shaanxi, Shijiazhuang and Handan in Hebei, Aksu in Xinjiang, Taian and Qingdao in Shandong, with an average detection rate of 28.6%. It was clarified that the pathogenicity of strains with co-infection of the two viruses and single infection of BdCV1 on branches, apple fruits, and pear fruits was significantly reduced. The vertical transmission efficiency of BdCV1 and BdVV2 was 100%, and the horizontal transmission efficiency was 9% and 3%, respectively. 【Conclusion】The strain WH-2L of B. dothidea with weak pathogenicity carries two viruses, BdCV1 and BdVV2. The detection rates of BdCV1 and BdVV2 in B. dothidea causing apple ring rot in six apple-producing regions in China were 53.6% and 28.6%, respectively. Both viruses can cause reduced pathogenicity in their hosts, with high vertical transmission efficiency and certain horizontal transmission efficiency, and have potential for development as biological control resources for apple ring rot.