To evaluate the cold resistance of newly released ‘Zhongzhe’ (ZZ) cultivars (‘ZZ 9’, ‘ZZ 14’, ‘ZG 1’ and ‘ZZFN 14-1854’), measurements were taken on sugarcane, and the physiological indices of leaves were analyzed following exposure to low temperatures. The results indicated that significant differences existed in the photosynthetic physiological indices of the four sugarcane varieties after low-temperature chilling. ‘ZZ 14’ exhibited relatively higher values in multiple parameters, namely Fv/Fm, Fv/Fo, net photosynthetic rate, photosynthetic pigment content, SPAD values (chlorophyll content), anthocyanin content, and superoxide dismutase (SOD) activity. In contrast, ‘ZG 1’ manifested lower values across these indicators, implying weaker cold tolerance. The other two cultivars demonstrated intermediate performance. It is indicated that ‘ZZ 14’ improves its cold resistance by increasing anthocyanin levels and SOD activity, thereby exhibiting superior cold tolerance. Conversely, ‘ZG 1’ presents relatively inferior cold resistance. The ranking of the cold resistance of the varieties from highest to lowest was ‘ZZ 14’> ‘ZZ 9’> ‘ZZFN 14-1854’> ‘ZG 1’.
In order to explore the suitable harvest period of industrial hemp and improve yield and quality, the effects of ‘Hanma 7’ and ‘Saima 1’ were used as experimental materials to analyze the impact of different harvest periods on the yield, yield traits and CBD (cannabidiol), CBG (cannabigerol) and THC (tetrahydrocannabinol) content of industrial hemp. The results showed that 90-111d after transplanting, the flower and leaf yields, plant height, stem diameter, first branch height, number of branches, dry weight of flower and leaf per plant and dry weight of stem per plant showed a significant increase trend with the extension of harvest time, and the yield and related traits of ‘Hanma 7’ performed better than ‘Saima 1’. The total CBD content, THC content and CBG content of the two varieties increased with the harvest time, and the total CBD content, THC content and CBG content of ‘Hanma 7’ were slightly higher than that of ‘Saima 1’. Correlation analysis showed that the flower and leaf yields and yield traits, main cannabinoid content of the two varieties were positively correlated with harvest time. The study has shown that appropriate delayed harvest period can effectively increase the yield and main cannabinoid content of industrial hemp.
Bacillus velenzensis GDND-2 could effectively control tobacco Fusarium root rot. In order to elucidate its growth-promoting effects on tobacco, specific primers were used to amplify relevant growth-promoting genes. The capabilities for indole-3-acetic acid (IAA) production, siderophore secretion, and ACC deaminase activity were tested by Sackowski colorimetry, CAS agar plate assays, and sole nitrogen source methods respectively. The phosphorus and potassium solubilization capacities were detected by transparent circle method. Defense enzyme activities in tobacco after GDND-2 treatment were measured by assay kits. The growth-promoting effects of GDND-2 on tobacco were verified by potting experiment. Results revealed that GDND-2 possessed the growth-promoting gene ysnE and exhibited strong IAA production capacity, reaching 24.16 mg/L after fermentation for 36 h. The strain demonstrated solubilization of organic phosphorus, inorganic phosphorus, and potassium. GDND-2 fermentation broth significantly enhanced peroxidase (POD) activity in tobacco leaves, showing a 707.88% increase in POD activity after 96 h of treatment. The strain displayed remarkable growth-promoting effect on tobacco seedlings, increasing fresh weight by over 87.21% and root length by more than 75.61%. So Bacillus velezensis GDND-2 demonstrated excellent IAA secretion capacity and significantly promoted tobacco seedling growth, establishing itself as a high-quality biocontrol strain with superior characteristics.
To advance molecular marker-assisted breeding of high yellow pigment (YP) wheat, this study validated the effectiveness of molecular markers associated with key enzymes (PSY, PDS, ZDS, and LCYE) in the YP biosynthesis pathway and oxidative enzymes (LOX, POD) responsible for flour bleaching. This was achieved by measuring flour YP content in 46 wheat varieties (lines). Functional markers YP7A and YP7B2 at the Psy-A1 and Psy-B1 loci, as well as dominant complementary functional markers LOX16 and LOX18 at the Lox-B1 locus, detected distinct allelic variations across the 46 wheat varieties (lines). The differences in mean flour YP content between these allelic variants reached highly significant levels (P<0.01). However, codominant functional markers YP4B1 and YP4B2 at the Pds-B1 locus showed no significant correlation (P=0.063) between allelic variations and flour YP content. Similarly, codominant functional markers POD3A1 and POD3A2 at the Pod-A1 locus revealed no significant differences in YP content between allelic variants, though Pod-A1a materials (low POD activity) exhibited slightly higher mean YP content compared to Pod-A1b materials (high POD activity). Functional markers YP7A, YP7B2, LOX16, and LOX18 are recommended for molecular marker-assisted breeding of high-yellow pigment wheat, whereas codominant markers YP4B1, YP4B2, POD3A1, and POD3A2 should be applied cautiously in such breeding programs.
The growth, physiological and photosynthetic characteristics of Brassica pekinensis seedlings under different temperature conditions were analyzed to determine the optimal temperature range for their growth. Taking B. pekinensis ‘Cold-resistant Golden Empress’ as test material, a completely randomized block design was used to set up eight temperature treatments of 0, 5, 10, 15, 20, 25 (control), 30 and 35℃. The plant height, root diameter, chlorophyll content, superoxide dismutase (SOD) activity, peroxidase (POD) activity, malondialdehyde (MDA) content, net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), intercellular CO2 concentration (Ci) were measured. The results showed that the seedlings began to die at 0℃. The plant height and root collar diameter increased slowly at 5-15℃ and 30-35℃. At 20℃, the plant height and root collar diameter were the largest, and the growth was good. The chlorophyll content, SOD activity and POD activity in the plant showed a trend of increasing first and then decreasing, and the MDA activity showed a trend of decreasing first and then increasing. With the change of time, Tr, Gs, Pn and Ci of B. pekinensis showed an upward trend. The Pn reached the maximum at 20℃, and the Gs, Tr and Ci of B. pekinensis seedlings were the largest at 35℃. Temperature lower than 20℃ or higher than 25℃ would affect the growth of B. pekinensis seedlings, resulting in a decrease in leaf enzyme activity and photosynthetic capacity. The optimum temperature range for the growth of B. pekinensis seedlings was 20-25℃, and the plant morphogenesis, physiological metabolism and photosynthetic performance were the best in this range.
In order to select high photosynthetic efficiency combinations of Capsicum annuum var. conoides varieties, the net photosynthetic rate (Pn), intercellular carbon dioxide concentration (Ci), stomatal conductance (Gs), water use efficiency (WUE), transpiration rate (Tr) and chlorophyll content of different C. annuum var. conoides varieties and their hybrid combinations at seedling stage were compared, and the correlation between heterosis and photosynthetic indexes was analyzed. The results showed that the four hybrid C. annuum var. conoides had significant heterosis at seedling stage, and the net photosynthetic rate, stomatal conductance and transpiration rate showed significant high parental heterosis, and the net photosynthetic rate was positively correlated with transpiration rate. Among them, the high parental dominance of net photosynthetic rate and stomatal conductance of ‘206’× ‘Tianyu’ were 42.99% and 63.52%, respectively, while the high parental dominance of transpiration rate was 92.16%, which had strong photosynthetic capacity and was a combination with potential development value.
In order to explore the effects of exogenous strigolactones (rac-GR24) on Cosmos bipinnatus seed germination, the seeds were treated with different concentrations (0, 0.1, 0.5, 1, 2, 5 μmol/L) of rac-GR24, and the effects of treatments on seed germination, morphological indicators and physiological characteristics were determined and analyzed. The results showed that compared with the control (0 μmol/L), the germination rates increased first and decreased afterward with different concentrations of rac-GR24 every day in the first three days, and reached the highest points in 1 μmol/L rac-GR24 treatment, and had no significantly difference on the 4th and 5th day. With the increase of rac-GR24 concentrations, fresh weight of aboveground parts in each treatment showed a decreasing trend, while fresh weight of underground parts and dry weight of aboveground parts both showed a trend of decreasing first and increasing afterward, however, dry weight of underground parts had no significantly difference, the length of aboveground and underground parts both showed a decreasing trend. The activities of α-amylase and β-amylase, contents of soluble starch and total soluble sugar were significantly increased at 18 h under applying exogenous 1 μmol/L rac-GR24 treatment, meanwhile ABA content was decreased, cZR content and GA29 content were increased, however IAA content had no significant change. The results indicated that exogenous SLs (rac-GR24) could stimulate the seeds germination of C. bipinnatus, and provided a theoretical basis for the mechanism and application of plant growth regulators in regulation of seed germination.
In order to accelerate propagation of elite variety of Arundo donax ‘Hangyu No.1’, and establish an efficient regeneration system, the stem segments of 3-year-old plants were used as explants to systematically explore the effects of sampling time and plant growth regulator combinations on the regeneration system. The results revealed that the best sampling time was in July and August, and the field plants were in a rapid growth period. The explant sterilization used 75% ethanol for 30 seconds and then 0.1% HgCl2 for 15-20 min, resulting in a survival rate of 90% approximately. The medium for axillary bud induction was MS+ 6-BA 4 mg/L+ IBA 1 mg/L, 92.66% buds developed obviously. Bud proliferation medium was MS+ 6-BA 7 mg/L+IBA 1 mg/L, resulting in a proliferation coefficient of 3.51. The rooting medium was 1/2MS+ NAA 0.2 mg/L, and the rooting rate reached 97.36%. The best time for plant transfer to ex vitro conditions was 7-10 days after rooting. The survival rate was 92.22% in all the transferred plants. The plants were further moved to the field at the end of April and then under the standard field management. In November of the same year, the plant grew up to 3-3.5 m high with 30-50 tillers. This research provides solid technical support for large-scale production of ‘Hangyu No.1’.
Highly heat-tolerant Lilium Asiatic hybrids can be used as breeding materials to improve heat tolerance and ornamental properties of L. davidii var. unicolor. L. davidii var. unicolor and 23 Lilium Asiatic hybrids were subjected to long-term natural heat stress in summer, and the heat damage index for each organ of the lilies was calculated. 10 lilies with different levels of heat tolerance were subjected to short-term heat stress at 42℃ for 18 h during the budding stage, and changes in the physiological indicators of leaves and buds were measured to comprehensively evaluate their heat tolerance. Under long-term natural heat stress, the heat damage index of each organ was analyzed using membership function and cluster analysis to select nine highly heat-tolerant germplasm: ‘Easy Whisper’, ‘Trendy San Fransico’, ‘Sugar Love’, ‘Tiny Double Dutch’, ‘Trendy Havana’, ‘Heart Strings’, ‘Corsage’, ‘Landini’ and ‘Tiny Double You’; 11 moderately heat-tolerant germplasm: ‘Tiny Diamond’, ‘Secret Kiss’, ‘Red Twin’, ‘Tiny Icon’, ‘Orange Cocotte’, ‘Golden Matrix’, ‘Tiny Rocket’, ‘Tiny Moon’, ‘Matrix’, ‘Tiny Ghost’ and ‘Trendy Dakota’; and four lowly heat-tolerant germplasm: L. davidii var. unicolor, ‘Tiny Ink’, ‘Trendy Savannah’ and ‘Tiny Comfort’. Under short-term heat stress during the budding stage, the leaves and buds of highly heat-tolerant germplasm showed relatively large increase in proline content and antioxidant enzyme (superoxide dismutase, peroxidase, catalase) activities, relatively small increase in hydrogen peroxide content, and varying extent of increase in relative electrical conductivity. The short-term simulated high-temperature heat tolerance evaluation based on the results of principal component analysis, membership function, and cluster analysis was basically consistent with the results of long-term heat stress evaluation. Comparisons indicated that the long-term natural high-temperature heat tolerance evaluation was relatively comprehensive and accurate and was in line with production practice. The short-term simulated high-temperature evaluation reflected the stress response of plant when exposed to high temperatures and partially reflected their true heat tolerance.
This article aims to study the differences in cold resistance among different germplasms of Euonymus and comprehensively evaluate their cold resistance, with the hope of screening out germplasm resources with strong cold resistance. Using one-year-old dormant branches from 10 different species and 11 different regions of Euonymus, the electrolyte leakage rate under low temperature stress was determined using the electrical conductivity method. Combined with the Logistic equation, the semi-lethal temperature LT50 was calculated to study the cold resistance of above 21 Euonymus plant materials. The results indicated that under low temperature treatment, the electrolyte leakage rate of the selected Euonymus plants exhibited an S-curve, but there were differences in the rate of increase among different genotypes. The semi-lethal temperature range was between -22.55 and -34.30℃. The order of cold resistance strength among 10 different species was: Euonymus maackii> Euonymus hamiltonianus> Euonymus porphyreus> Euonymus fengchengensis> Euonymus verrucosus> Euonymus macropterus> Euonymus nanus> Euonymus phellomanus> Euonymus schensianus> Euonymus nanus. The order of cold resistance ability in different regions was Montreal, Canada; Taigu of Shanxi, China; McGill, Canada; Ningxia, China; Chengde of Hebei, China; Phuket, Japan; Shenyang of Liaoning, China; Changchun of Jilin, China; Yuci of Shanxi, China; Nanyang of Henan, China; Handan of Hebei, China. Euonymus maackii, Euonymus bungeanus, and Euonymus macropterus are relatively more resistant to cold stress compared to other varieties.
The paper aims to explore the optimization of planting structure in gravel-mulched land in Ningxia. Lonicera ‘Four Seasons’, Lonicera gaponice, Lonicera ‘Beihua 1’, Lonicera ‘Pingyi’ and Lonicera ‘Jiufeng1’ were used as the main research materials, the leaf anatomical structures of five Lonicera japonica were observed and compared using scanning electron microscopy, anatomical structure and drought resistance of five honeysuckle varieties were studied. The results showed that: (1) the upper epidermis thickness, lower epidermis thickness and cuticle thickness of Lonicera ‘Beihua 1’ were 38.30, 15.90 and 6.60 μm, respectively, which were significantly higher than those of other varieties. (2) The stomatal density and length and width of five kinds of honeysuckle from high to low were Lonicera ‘Beihua 1’, Lonicera ‘Four Seasons’, Lonicera gaponice, Lonicera ‘Pingyi’ and Lonicera ‘Jiufeng 1’. Lonicera ‘Beihua 1’ was significantly higher than other varieties. (3) The leaf vein density of Lonicera ‘Beihua 1’ was the smallest, and the main vein thickness was the largest, which was significantly different from other varieties. (4) The mesophyll thickness and sponge tissue thickness of Lonicera ‘Beihua 1’ were the highest of 222.6 and 107.7 μm, which were 1.26 and 1.16 times of Lonicera ‘Four Seasons’, 1.22 and 1.32 times of Lonicera gaponice, 1.34 and 1.63 times of Lonicera ‘Pingyi’, 1.6 and 1.69 times of Lonicera ‘Jiufeng1’, respectively. In summary, Lonicera ‘Beihua 1’ has the strongest drought resistance, and the drought resistance of Lonicera ‘Pingyi’ and Lonicera ‘Jiufeng 1’ is relatively weak. When introducing honeysuckle varieties in Ningxia gravel-mulched land, priority should be given to Lonicera ‘Beihua 1’.
To investigate the varietal differences in cadmium (Cd) absorption and accumulation among different rice varieties, a field experiment was conducted with 10 rice varieties in slightly Cd-contaminated farmland. The variations in Cd absorption and accumulation capacities were compared. The results demonstrated that grain yields of different rice varieties ranged from 7.60 to 10.77 t/hm2, with the highest yield observed in the cultivar ‘Liangyou 5078’, which was significantly higher than other varieties (P<0.05). The Cd content in brown rice of different varieties ranged from 0.177 to 0.503 mg/kg, with the Cd concentration in ‘Zhennuo 29’ being lower than the national limit standard (0.20 mg/kg). The enrichment factors of brown rice for total soil cadmium (Cd) in different rice varieties ranged from 0.281 to 0.858, all below 1. The enrichment factor of ‘Zhennuo 29’ was significantly lower than other varieties (P<0.05). Rhizosphere Soil pH values at the maturity stage varied between 5.49 and 6.93 across varieties, with a mean value of 6.27. The total Cd and available Cd contents in soil ranged from 0.407 to 0.827 mg/kg and 0.180 to 0.293 mg/kg, respectively, with average values of 0.634 mg/kg and 0.252 mg/kg. Through input-output ratio analysis of different rice varieties, the ratio for ‘Zhennuo 29’ reached 1.81, which was significantly higher than other varieties (P<0.05). The study demonstrates that ‘Zhennuo 29’ can be cultivated as a low-Cd-accumulating rice variety in safe utilization farmland in the region with high economic value.
The study aimed to optimize the preparation process of ginger straw modified biochar through the response surface method to enhance its adsorption performance of ammonia nitrogen, so as to provide a new material for solving the problem of agricultural nitrogen pollution. The adsorption performance of modified biochar on ammonia nitrogen was evaluated by adsorption experiments. Initially, single-factor experiments were conducted with factors such as carbonization temperature, carbonization time, concentration of phosphoric acid solution and liquid-solid ratio, and then response surface experiments were performed based on above findings. The results indicated that the optimal process condition was as followed: carbonization temperature of 615℃, carbonization time of 1.5 h, phosphoric acid concentration of 25%, liquid-solid ratio of 15 mL/g. Under this condition, the adsorption value of modified biochar to ammonia nitrogen was very close to the predicted value. This study effectively applied the response surface method to optimize the modification technology of biochar, and provided a new solution for managing nitrogen pollution in practical agricultural practices.
In recent years, reactive nitrogen emissions have risen dramatically due to the rapid development of industrialization and agricultural intensification. Nitrogen deposition has become one of the critical driving factors of global change, which has a profound impact on forest ecosystems, especially the structure and diversity of soil microbial communities. Nitrogen deposition affects the structure and diversity of microbial communities directly or indirectly. In simulated atmospheric nitrogen deposition experiments, different nitrogen addition types and methods have varying effects on soil microbial communities. Furthermore, the interaction of nitrogen deposition with other environmental factors further complicates its effects on microbial communities. This paper synthesized the latest research progress on the effects of nitrogen deposition on soil microbial communities in temperate (including cold -temperate) forest ecosystems to enhance the understanding of the mechanisms of nitrogen deposition affecting soil microbes, and pay attention to the impacts of microbial community shifts on ecosystem functions, and provide scientific theoretical support for addressing the challenges posed by global climate change.
Medicinal plants are affected by various factors during the cultivation process, among which rhizosphere microorganisms exhibit a close relationship with medicinal plants, with both interacting and influencing each other. In this paper, the research progress of the interaction between medicinal plants and rhizosphere microorganisms in recent years is summarized, focusing on the effects of rhizosphere microorganisms on growth, secondary metabolic products, disease resistance and continuous cropping obstacles of medicinal plants, as well as the effects of medicinal plant types (or varieties), production area, growth period, planting age and planting pattern on rhizosphere microorganisms. In addition, the paper also identifies the current problems in this research field and proposes directions for future investigations. This review aims to provide theoretical insights and methodological references for rationally utilizing the interaction between medicinal plants and rhizosphere microorganisms to enhance plant growth, resist pathogen invasion, alleviate continuous cropping obstacles, increase yield and improve the quality of medicinal materials.
To gain a deeper understanding of the research foci, development status, and hotspots in the field of apple tree fertilization, and to provide reference for the future research directions of apple tree fertilization practices, this paper conducted a retrieval of relevant literature from 2000 to 2023 based on the core paper databases of CNKI and Web of Science. Using analysis tools such as VOSviewer and CiteSpace, we performed a visual analysis of the publication volume, publishing institutions, authors of the 761 collected papers, as well as keyword co-occurrence, clustering, and emergence, and constructed a knowledge map in the field of apple tree fertilization. The results indicate that significant progress has been made in apple tree fertilization research in recent years, improving fruit quality, optimizing fertilization strategies, and reducing environmental pollution have become research hotspots. The annual publication volume generally shows an upward trend, with the formation of large-scale research teams and institutions. Keywords such as yield, quality, and soil nutrients remain current and future research hotspots. It is predicted that green manure, sustainable development, soil improvement, and precision fertilization may become hot research directions in the field of apple tree fertilization.
Water scarcity and substantial carbon emissions in farmlands are critical factors restricting the high-quality development of agriculture in China. How to improve water use efficiency and reduce carbon emissions in agriculture production while ensuring output is the focus of current research. In order to understand the source and generation mechanism of carbon emissions in farmland and the impact mechanism of drip irrigation technology on carbon emissions, this paper reviewed the current research status of drip irrigation affecting carbon emissions in farmland at home and abroad and summarized the main achievements, existing problems and future developments trends of current research. Analysis results showed that tillage and residue dispose, the production and use of agricultural materials, and farmland management were the three main sources of carbon emissions. Meanwhile, it was found that carbon emissions in farmland could be affected by drip irrigation through reducing the energies consumption in agricultural irrigation, improving utilization efficiency of resources, and improving soil environment. The research results are helpful to improve the technical system of drip irrigation systems, promote farmland water conservation and emission reduction, and provide a theoretical basis for achieving ‘dual carbon’ goals in China.
The study aims to screen and obtain highly efficient biocontrol strains against tobacco root rot disease, providing germplasm resources for the biological control of tobacco root rot disease. Root rot fungi from diseased tobacco was isolated and purified by tissue separation method. The types of pathogenic bacteria were determined by morphological and molecular biological methods, and the biocontrol bacteria with good antagonistic effect against pathogenic bacteria were screened from tobacco planting soil, and their species were identified by molecular biological methods. The effect on tobacco root rot disease control and tobacco growth index was evaluated by plate confrontation and indoor pot test. The results showed that among the 6 fungi isolated and purified from diseased tobacco roots, only strain L1 could infect tobacco, exhibiting symptoms consistent with field infections and strong pathogenicity. It was identified as Fusarium oxysporum. 6 functional strains were screened via the plate confrontation method, among which bacterial strain B10 showed the highest inhibition rate (57.66%) against F. oxysporum and was identified as Bacillus velezensis B10. Pot experiments demonstrated that B10 effectively reduced the incidence of tobacco root rot, achieving a control efficacy of 63.63%, outperforming the chemical agent carbendazim (27.27%). Additionally, strain B10 promoted tobacco growth: compared to the control (CK), it significantly increased maximum root length, plant height, stem base diameter, aboveground fresh weight, and root fresh weight by 17.32%-37.67%. The B. velezensis B10 strain screened in this study effectively inhibits F. oxysporum, reduces the incidence and severity of tobacco root rot, and significantly promotes tobacco growth, demonstrating promising biocontrol potential.
The study aims to explore the effect of β-glucanase on the activity of defense enzymes in pepper plants and its biological control effect on common pepper soil borne diseases, providing new reference directions for the biological control of pepper soil borne diseases. Pepper seedlings were treated with β-glucanase solution purified by agarose gel chromatography. The activities of SOD, POD, PPO, PAL, CAT, APX and GR in the leaves of pepper seedlings were measured at the seedling stage, the first flowering stage and the fruit setting stage, respectively, and the content of MDA was measured simultaneously. Artificial inoculation was used to investigate the biocontrol effects of different concentrations of β-glucanase treatment on pepper blight, pepper wilt, and pepper anthracnose during the seedling and fruit setting stages. The research results showed that β-glucanase treatment had no effect on GR activity, but promoted the activities of SOD, POD, PPO, PAL, CAT, and APX to varying degrees in peppers, and β-glucanase treatment also had a significant inhibitory effect on MDA content. The control effects of β-glucanase diluted 10-100 times on pepper blight, pepper anthracnose, and pepper wilt were 47.08%-82.23%, 42.35%-70.25%, and 44.21%-65.92%, respectively. β-glucanase can increase the activity of pepper defense enzymes, enhance plant resistance, and has significant biocontrol effects on pepper blight, pepper anthracnose, and pepper wilt. As a biocontrol agent, β-glucanase is environmentally friendly and does not cause insect resistance, making it a promising new biopesticide for controlling pepper soil borne diseases.
The paper aims to scientifically evaluate the safety of nine fungicides on lychees. A method of the simultaneous detection for 9 fungicides in lychee was established by a high-performance liquid chromatography-tandem quadrupole-time of flight-mass spectrometry (HPLC-Q-TOF/MS). The QuEChERS pre-treatment salt package were firstly added in homogenized samples, and then extracted with acetonitrile. The automated QuEChERS sample processing platform was shaken for 10 minutes to remove impurities of lychee. The data were collected by HPLC-Q-TOF/MS. The calibration curves of 9 fungicides showed good linearity in a concentration range of 0.001-0.1 mg/L (R2>0.99). The average recoveries were 76.6%-114.8% at three spiked levels (0.005, 0.05, 0.1 mg/kg), while the relative standard deviations (RSD) were 1.4%-16.4%. The limits of detection and limits of quantification were 1 μg/kg and 3 μg/kg, respectively. The residue samples were analyzed by using the established detection method. The results showed that the residues of pyrazoxystrobin, azoxystrobin, difenoconazole, and metalaxyl in the whole lychee were all below the maximum residue limit values (MRLs) set by China. The established analytical method is reliable, simple and fast, and suitable for batch samples detection.
To analyze the nutritional component characteristics of Albas goat meat, and provide a reference for evaluating its nutritional quality, 39 Albas goats aged 1.5-4 years were selected as experimental subjects. Fatty acids, amino acids, conventional nutrients, and mineral elements of the goat meat were analyzed using Chinese National Standard methods. The ratios of essential amino acids (EAA) to non-essential amino acids (NEAA) were 67.4% and 70.1%, respectively, with EAA/total amino acids (TAA) values approximately 40% in the biceps femoris and longissimus dorsi muscles. Glutamic acid, aspartic acid, lysine, and leucine were the most abundant amino acids. Cholesterol content was low, while palmitic acid and stearic acid levels were significantly lower than those in other goat breeds. Calcium, iron, manganese, and zinc contents were notably higher compared to other breeds. Significant differences (P<0.05) were observed between the biceps femoris and longissimus dorsi in moisture, fat, palmitic acid, and palmitoleic acid content. Specifically, fat and oleic acid levels were markedly higher in the longissimus dorsi. No significant inter-muscle differences were detected in other nutritional components. Albas goat meat exhibits distinct amino acid composition compared to other breeds, with a balanced amino acid profile indicating high-quality protein. It is characterized by the highest oleic acid content, low cholesterol, low palmitic and stearic acids, and high content of calcium, iron, manganese, and zinc. There are significant differences in moisture, fat, palmitic acid, and palmitoleic acid content between muscles, but there are no significant differences in amino acid and mineral element contents. The experimental results on these nutritional characteristics may support nutritional quality assessment, authenticity verification, and traceability studies of Albas goat meat products.
The paper aims to investigate the effect of exogenous glycine betaine on seed germination, especially the respiration during germination, under low temperature stress. This study used the Sorghum bicolor× S. sudanense variety ‘Youmu 2’ as the experimental material to investigate the effects of glycine betaine (GB) on respiratory electron transfer during seed germination and seedling growth under low temperature stress. The results indicated that: 15 mmol/L GB treatment significantly increased the germination potential, germination index, germination rate, shoot length, and root length of Sorghum bicolor× S. sudanense seeds during low-temperature germination. It also significantly increased the total respiration rate, COX respiration rate, AOX respiration rate, and the proportion of COX in the total respiration of Sorghum bicolor× S. sudanense seeds during low-temperature germination. However, it had no significant effect on the proportion of AOX in the total respiration. Its effect on the proportion of COX respiration and AOX respiration in total respiration gradually decreased with increasing temperature, significantly increasing the SOD activity, POD activity, and CAT activity of Sorghum bicolor× S. sudanense seeds during low-temperature germination, and significantly reducing their H2O2 content. It significantly improved the SOD activity, POD activity, and CAT activity of Sorghum bicolor× S. sudanense seeds during low-temperature germination, and significantly reducing their H2O2 content. The germination rate, germination potential, germination index, shoot length, and root length of Sorghum bicolor× S. sudanense seeds under low temperature germination with 15 mmol/L GB treatment showed a highly significant or significant positive correlation with AOX respiration rate, COX respiration rate, and total respiration rate, and a highly significant or significant negative correlation with CAT activity, SOD activity, POD activity, and H2O2 content. The plant height, root length, stem length, and leaf length of Sorghum bicolor× S. sudanense seedlings grown at low temperatures under 15 mmol/L GB treatment showed a highly significant or significant positive correlation with total fresh mass, aboveground fresh mass, and underground fresh mass, and a highly significant or significant negative correlation with H2O2 content. Therefore, GB could increase the respiration rate of COX and AOX in seeds, enhance the antioxidant enzyme activity of seeds and seedlings, reduce the production of reactive oxygen species, effectively alleviate the oxidative damage to seeds and seedlings under low temperature stress, promote the germination of Sorghum bicolor× S. sudanense seeds and the growth and development of its seedlings under low temperature stress.
