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Research Progress of Ubiquitin/26S Proteasome Pathway Regulating Crop Seed Size CUI Chao, ZHAO Ahui, LI Fang, GAO Xiang, XING Lingling , DONG Jian, ZHAO Wanchun, YANG Mingming, Journal of Agricultural Science and Technology    2021, 23 (9): 19-29.   DOI: 10.13304/j.nykjdb.2021.0053 Abstract （351）      PDF （3329KB）（2538）       Knowledge map    Save Ubiquitin/26S proteasome system (UPS) is an essential pathway of protein ubiquitination. As a post-translational modification process, UPS plays an important role in all crop growth and development stages. Many studies have shown that ubiquitin receptor protein,  E3 ubiquitin ligase, and deubiquitinase in UPS could coordinate with each other. By connecting or removing different amounts of ubiquitin on the target protein, they could mediate the degradation of the target protein, change the subcellular localization and protein activity and regulate the seed size. This paper reviewed the research progress of ubiquitin/26S proteasome system regulating seed size in different crops. Its future development was prospected to provide a reference for the study of seed size regulation mechanism and breeding improvement. Related Articles | Metrics

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Principles of Microbial Electrochemical Technology and Its Application in the Recycling of Livestock and Poultry Wastes Kunhong JIANG, Zhenying XU, Zhenzhen GUO, Lin BAI, Xiaoxia HAO, Dongmei JIANG, Shixiu QIU Journal of Agricultural Science and Technology    2024, 26 (7): 210-222.   DOI: 10.13304/j.nykjdb.2022.1053 Abstract （273）   HTML （3）    PDF （1655KB）（1608）       Knowledge map    Save The environment has been under great pressure as a consequence of the livestock waste discharged in the course of intensive production of livestock and poultry farming. By studying the elemental theory of respiratory metabolism， comprised of small molecule acid metabolism of Geobacter sulfurreducens， the aerobic and anaerobic metabolism of Shewanella oneidensis， as well as extracellular electron transfer directly contacted and mediated by electrically conductive pili and electron shuttle substances， the central carbon metabolism pathway， basic extracellular electron transport process and main regulatory mechanisms of model electroactive microorganisms were examined. Owing to insights into the respiration and metabolism of electroactive bacteria， a variety of microbial electrochemical systems （MES） mainly based on microbial fuel cell， microbial electrolytic cell and electric-field-assisted aerobic compost had been developed and optimized. Not only MES were employed to reduce contents of hazardous substances including chemical oxygen demand， greenhouse gases， antibiotics and resistance genes， but they were also used to improve power generation efficiency， cathode high value-added products and humus contents of compost. The research progress of microbial electrochemical theory and thoroughly demonstrates the application of microbial electrochemical technology in the recycling of livestock and poultry waste were reviewed， so as to provide reference and theoretical foundation for the study of livestock waste utilization. Table and Figures | Reference | Related Articles | Metrics

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Research Progress of Plant microRNAs in Drought Stress Response ZHANG Haoyang, JIN Yinan, SUN Yanxin, LI Ziwei, GUO Xiaoheng, XU Zicheng* Journal of Agricultural Science and Technology    2021, 23 (4): 27-36.   DOI: 10.13304/j.nykjdb.2020.0354 Abstract （289）      PDF （3927KB）（1543）       Knowledge map    Save Drought is a common and recurring climate feature that seriously affects crop production. microRNAs (miRNAs) are a class of small molecular non-coding RNAs with the length of 18~24 nt. Transcribed miRNAs regulate gene expression and participate in plant growth and development. This paper focused on the discovery, synthesis and mechanism of miRNAs, the species and target genes of miRNAs in response to drought stress, and the mechanism of miRNAs in response to drought stress. It was pointed out that microRNAs were species-dependent and tissue-specific in plant response to drought stress, and were affected by drought stress conditions. It was also found that the current plant microRNAs in drought stress response of the study was the mechanism of action of miRNAs in drought stress and its target gene regulatory network was unclear. The research prospects for the future, such as exploring miRNAs regulate gene regulation of cis component characteristics, and the target genes of plant drought stress response function and network of the interaction between the key factors, and the construction of plant drought resistance microRNAs repository was discussed, in order to promote the application of miRNAs in  plant resistance to drought stress. Related Articles | Metrics

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Research Advances on Plant Root Exudates in Response to Cadmium Stress Xiang WU, Juan LI, Yan CAO, Yanrong CHENG, Xuyu YAN, Ling LI Journal of Agricultural Science and Technology    2023, 25 (7): 12-20.   DOI: 10.13304/j.nykjdb.2022.0619 Abstract （464）   HTML （5）    PDF （530KB）（1056）       Knowledge map    Save With the rapid development of industry and agriculture and the the casual discharge of waste， heavy metal pollution has been serious in farmland soil. Cadmium （Cd） pollution is more serious in heavy metal pollution. The technology of in situ remediation by hyperaccumulative plants is the main means to remediate cadmium and other heavy metal pollution. Root is the first part of plants to contact with heavy metals such as Cd. As an important carrier， root exudates can conduct material exchange and energy transfer between plants， soil and microorganisms， and it can effectively regulate the rhizosphere microenvironment， affect the behavior of heavy metals in the rhizosphere environment， ultimately affect the absorption and transport of heavy metals by plants， and then affect the growth and development of plants themselves. This paper briefly described the effects of Cd stress on plant growth and development， analyzed the response of different kinds of root exudates under Cd stress， as well as the effects of root exudates on soil physical and chemical properties， rhizosphere microorganisms， the accumulation and transport of Cd，and analyzed the expression of genes pathways related to cadmium stress. In addition， regarding heavy metal pollution， this paper looked forward to the research trend of root exudates in order to explore the response mechanism of plant root exudates to cadmium stress in the future. Reference | Related Articles | Metrics

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Physiochemical Properties and Microbial Community Structure in Rhizosphere Soil of Dracocephalum tanguticum Erhao ZHANG, Panpan LIU, Ping HE, Yue JIAN, Yuting XU, Chengxin CHEN, Yazhou LU, Xiaozhong LAN, Sangmu SUOLANG Journal of Agricultural Science and Technology    2024, 26 (3): 201-213.   DOI: 10.13304/j.nykjdb.2022.0741 Abstract （237）   HTML （11）    PDF （4097KB）（696）       Knowledge map    Save In order to study the physiochemical properties and microbial community structure in rhizosphere soil of Dracocephalum tanguticum， the microbial communities in rhizosphere soil from Gongbujiangda （GB）， Kanuo （KR） and Luolong （LL） in Tibet were as materials. The microbial community in rhizosphere soil of D. tanguticum was analyzed by illumine high-throughput sequencing， and the physiochemical properties were determined and their correlation with core microbial communities were studied. The results showed that there were significant differences among different regions in the physiochemical properties. A total of 3 900 bacterial OTUs and 1 990 fungal OTUs were obtained in rhizosphere soil of D. tanguticum from 3 regions. The microbial diversity index in the rhizosphere soil of D. tanguticum grown in different regions was significant difference. Actinobacteria was the dominant bacterial phyla in all samples of D. tanguticum. Basidiomycota was the dominant fungal phyla in GB sample， Ascomycota was the dominant fungal phyla in KR and LL samples. The dominant genus was difference among different samples. Principal component analysis showed that the compositions of bacterial and fungal community were different among different samples. The analysis of core microbial communities showed that there were 257 core bacterial genera and 102 fungal genera. The correlation analysis showed that the changes of microbial community in rhizosphere soil were correlated with the physiochemical properties， and the contents of total potassium， available potassium， total phosphorus， total nitrogen and available nitrogen were the key determinants affecting the composition of microbial community in rhizosphere soil of D. tanguticum. Overall， the microbial community structure in rhizosphere soil of D. tanguticum grown in the different regions were significant differences， and the microbial community structure of rhizosphere soil was strongly linked to the physiochemical properties of rhizosphere soil. Above results provided theoretical bases for artificial cultivation and screening beneficial microorganisms of D. tanguticum. Table and Figures | Reference | Related Articles | Metrics

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Biological Function Insights into the Ubiquitin/26S Proteasome Pathway in Rice XU Dandan1,2, SUN Fan2, WANG Yinxiao2, SHI Yingyao1*, WANG Wensheng2*, FU Binying2 Journal of Agricultural Science and Technology    2018, 20 (1): 25-33.   DOI: 10.13304/j.nykjdb.2017.0144 Abstract （381）      PDF （2267KB）（1704）       Knowledge map    Save There are two different protein degradation patterns in vivo, one pattern is energy-dependent and another is energy-independent. Ubiquitin/26S proteasome pathway (UPP) is an exceedingly high-efficient, specific and ATP-dependent route for protein removal. In eukaryote, ubiquitin/26S proteasome pathway is involved in 80%~85% protein degradation. In plant species, the ubiquitin/26S proteasome pathway regulates fundamental processes of growth and development, and it is one of the most important and fine regulation mechanisms for protein efficient and specific degradation in plants. This paper summarized the ubiquitin/26S proteasome pathway, and emphasized on the protein structure of E2 and E3 and their biological function and mechanism in rice growth and development, hormone signaling, biotic and abiotic stress response. The paper also prospected the further study, which would be helpful for revealing the fine control process of ubiquitin/26S proteasome pathway during rice growth and development, thus to provide guidance and reference for rice stress resistance breeding. Related Articles | Metrics

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Analysis on miRs Expression Profiles of Alfalfa and Screening of Trans-border Potential miRs Jingying JIA, Yahui LI, Bingzhe FU, Yun MA, Xiaoyan CAI Journal of Agricultural Science and Technology    2023, 25 (7): 43-53.   DOI: 10.13304/j.nykjdb.2021.1090 Abstract （211）   HTML （0）    PDF （1938KB）（945）       Knowledge map    Save To explore miRNA expression profile of ‘Xinyan 52’ （XY52）， a new drought tolerant alfalfa line cultivated in Ningxia， and screen microRNA （miR） with cross-border research value， ‘Zhongmu 1’ （ZM1） was as the reference. ZM1 and XY52 were sequenced and analyzed by high-throughput miRs （RNA-seq）； the bioinformatics technology was used to screen differential expressed miRs and predict target genes， and the predicted target genes were enriched and analyzed by GO and KEGG； then 10 miRs were detected and analyzed by RT-qPCR. The results were as follows： ① the miRs expression profiles of 2 kinds of alfalfa were successfully constructed， and 656 and 703 miRs were detected in ZM1 and XY52， which the number of newly predicted miRs were 233 and the known miRs were 433 and 480； ② a total of 21 differential expressed miRs were detected in the two alfalfa varieties， among which 3 miRs including novel-miR54， miR156f and miR166a were expressed higher， and the expression of novel-miR54 in XY52 was significantly higher than that in ZM1 （P<0.01）， and the expression of miR156f in ZM1 was significantly higher than that in XY52 （P<0.01）； ③ among the five miRs which had cross-border regulatory functions， miR166a had the most expressive level in ZM1 and XY52， while the expression of miR166a in XY52 was significantly higher than that in ZM1 （P<0.01）； ④ a total of 623 target genes were predicted by the KEGG pathway and GO function enrichment analysis of 21 miRs with differential expression， which were mainly related to signaling pathways such as RNA transport， ABC transporter and ubiquitin-mediated proteolysis. These results laid a preliminary foundation for the analysis of miRs in differences of alfalfa and the regulation of genes in dairy cows. Table and Figures | Reference | Related Articles | Metrics

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Analysis of Meat Quality， Nutritional Components and Expression Characteristics of Meat Quality-related Genes in Tibetan Sheep at Different Altitudes Liangwei YAO, Yuzhu SHA, Xinyu GUO, Xiaoning PU, Ying XU, Jiqing WANG, Shaobin LI, Zhiyun HAO, Xiu LIU Journal of Agricultural Science and Technology    2024, 26 (3): 66-75.   DOI: 10.13304/j.nykjdb.2022.0385 Abstract （360）   HTML （11）    PDF （1113KB）（1150）       Knowledge map    Save In order to study the difference of meat quality and the expression characteristics of meat quality-related genes in Tibetan sheep at different altitudes， the meat quality and nutritional components of longissimus dorsi， triceps brachii and biceps femoris of Tibetan sheep at altitude 2 500， 3 500 and 4 500 m were determined， and the expression levels of meat-related genes （H-FABP， LPL， MC4R and CAST） were determined and their correlations were analyzed. The results showed that the Tibetan sheep meat of low altitude had lower shearing force， lower water loss rate， higher tenderness and better taste， especially longissimus dorsi was better than the other 2 parts. The Tibetan sheep meat of high altitude had higher cooked meat rate and higher meat yield. The contents of mineral and crude protein in high altitude Tibetan sheep meat were higher， while the low altitude Tibetan sheep meat was more succulent. Compared with the two leg muscles， the longissimus dorsi had better taste. The expression levels of genes related to meat quality were differences among different altitudes. Among them， H-FABP had the highest expression levels in different muscles at mid-altitude， and LPL， MC4R and CAST had the highest expression levels in biceps femoris of Tibetan sheep at low altitude， and was higher in the longissimus dorsi of Tibetan sheep at middle and high altitude. The correlation analysis showed that the expression levels of H-FABP， LPL， MC4R and CAST genes were significantly correlated with cooked meat rate， shear stress， water loss rate， ash， crude fat， crude protein and dry matter in Tibetan sheep. It showed that the meat quality and nutritional components of Tibetan sheep at different altitudes were different， and the expression levels of meat-related genes in different parts were also different， which affected the meat quality of Tibetan sheep. Above results provided basis for meat selection and genetic improvement of Tibetan sheep at different altitudes. Table and Figures | Reference | Related Articles | Metrics

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Prospects for Commercialization of Biotech Breeding Technology of Important Crops in China Jian ZHANG Journal of Agricultural Science and Technology    2022, 24 (12): 15-24.   DOI: 10.13304/j.nykjdb.2022.0697 Abstract （1267）   HTML （12）    PDF （538KB）（690）       Knowledge map    Save China has more population in the world but with limited arable land and water resources. Scientific innovation becomes a unique solution to promote the crop productions for national food security. Commercialization of biotech breeding technology in maize， soybean， oil rape and cotton has played a critical role in seed industry developmentin these major crop production countries including US， Brazil and Argentina. After over 20 years’ scientific innovation of biotech crop research and development （R&D） in China， the biotechnology crops for maize and soybean with resistance to insect and herbicide tolerant traits have been ready， these biotech crops would not only reduce the inputs of crop production， but also increase the yield and farmers’ incomes significantly. Due to the commercialization of biotech breeding technology involves in multiple aspects of research and development of scientific innovation， regulatory appraisal of biosafety and stewardship requirements， international trade， agricultural production and public acceptance etc.， which is a large and complex system engineer. Therefore， only those of the larger seed enterprises with capabilities can lead the whole processes by integrating R&D resources of scientific， academic and seed industrial units to create an innovation consortium for collaborations across the whole R&D chain and commercial chain together. Such an innovation consortium will be capable to continuously launch new varieties with better-yielding， nutritious， less inputs and environmental-friendly products should steadily support the commercialization of biotech breeding technology of important crops towards a sustainable and high-quality development of seed industry in China. Biotech breeding technology is the core of seed innovation， so establishing an innovative system for modern breeding and strengthening the deep mine of germplasm resources plus breaking through the key technologies of cutting-edge breeding for strategic new varieties， becomes the solution for germplasm improvement and a key for winning the seed industry as well as the fundamental support for firmly grasping the initiative of food security. This paper summarized the application of biotech breeding， and proposed the developmental strategies of modern seed industry. Biotech breeding technology will become the important approach to solve the germplasm resource shortage and environmental constrains faced by China’s agricultural development while driving the development of China’s modern seed industry and the continuous improvement of international competitiveness， and realizing the leap from a large seed industry to a strong seed country. Table and Figures | Reference | Related Articles | Metrics

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Research Progress on Structure Constitution, Biological Function and Separation Methods of Plant Cuticle GAO Sen, WANG Yahong, SHAO Huifang, XU Zicheng, NIU Lulu,CHEN Zheng, ZHANG Haicong, HUANG Wuxing* Journal of Agricultural Science and Technology    2018, 20 (3): 46-54.   DOI: 10.13304/j.nykjdb.2017.0209 Abstract （566）      PDF （1135KB）（1397）       Knowledge map    Save The cuticle membrane consists of cutin and wax. It is a layer of hydrophobic lipid material covering the upper parts of plant, like flower, leaf and non-woody stem organs. It has the functions of limiting water plant excessive loss, resisting ultraviolet radiation, preventing pest invasion, and plays protective roles in the process of plant growth and development, and adaptation to biotic and abiotic stresses. It is very important to study cuticle structure and chemical composition, which are the main reasons influencing its biological function. The paper reviewed the structure composition, biological function and commonly used methods for its separation; discussed problems existing in research, hoping to provide theoretical references for studying its physiological and biological functions in the future. Related Articles | Metrics

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Development Status and Prospects of Rice Industry in Heilongjiang Province Yingnan GU, Xin LIU, Jingyuan WANG, Xinyu DUAN, Ying HUANG, Qingjuan LIN, Yanxia LIU, Hongwen BI Journal of Agricultural Science and Technology    2023, 25 (12): 17-25.   DOI: 10.13304/j.nykjdb.2022.1005 Abstract （694）   HTML （17）    PDF （1755KB）（882）       Knowledge map    Save In recent years， the rice industry in Heilongjiang province has developed well in planting， production and marketing， but there are still some problems such as quality degradation and low efficiency of processing enterprises. In order to promote the development of high-quality rice industry in Heilongjiang province， and improve productivity and efficiency，based on the statistical yearbook data of Heilongjiang province， field survey information and literature data， this paper analyzed the change characteristics of rice variety breeding， production and planting， quality， processing and sales of japonica rice in Heilongjiang province from 2016 to 2021， put forward suggestions to accelerate the development of rice industry in Heilongjiang province， including the construction of research and innovation center of seed industry， the construction of green ecological demonstration area and the strengthening of rice processing industry， which provided a variety of feasible ideas for the development of rice industry in Heilongjiang province. Table and Figures | Reference | Related Articles | Metrics

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Research Review on Modeling and Simulation for Pesticide Spraying System Jiaqiang ZHENG, Huichun ZHANG, Youlin XU, Hongping ZHOU Journal of Agricultural Science and Technology    2024, 26 (3): 76-90.   DOI: 10.13304/j.nykjdb.2022.0776 Abstract （293）   HTML （13）    PDF （2797KB）（1120）       Knowledge map    Save The effect of pesticide application is closely related to the pesticide spraying process. The modeling and simulation of pesticide spraying process can solve the difficulties in field experimental research caused by the difference of plant growth cycle， the different occurrence of pests and diseases， and the uncontrollable natural field environments. According to the resistance， resurgence， residue （3R）/efficacy， efficiency， eco-environment （3E）/method， model， measurement （3M） of the pesticide applications， the modeling and simulation researches on the pesticide spraying process， such as atomization， transportation and deposition， were summarized and analyzed. The semi-physical simulation system of pesticide spraying was put forward and analyzed based on the development of simulation technology. Finally， several research suggestions were proposed to promote research on innovative precision pesticide spraying technology and R&D of high-quality plant protection machinery， such as establishing atomization model for carrying out the atomization mechanism of new nozzles， the multi-phase flow field simulation of mass pesticide droplets， the spraying target customization and target recognition model， the comprehensive pesticide droplet drift model， and the coupling between plant growth model and pesticide spraying system. Table and Figures | Reference | Related Articles | Metrics

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Research Advance on Drought Stress Response Mechanism in Plants WANG Kaiyue, CHEN Fangquan, HUANG Wuxing* Journal of Agricultural Science and Technology    2019, 21 (2): 19-25.   DOI: 10.13304/j.nykjdb.2018.0115 Abstract （1316）      PDF （1029KB）（1022）       Knowledge map    Save Drought stress is one of the major limitations to plant growth and development. Drought can lead to osmotic imbalance, damage of membrane system, decrease of respiration rate and photosynthesis rate, etc. adverse reaction. It not only hinders plant growth and metabolism at different stages, but also affects crops to achieve good quality and high yield. In the interaction between plants and external environment, plants will build drought response, such as changing the structure of plant root system and leaf blades, composition of metabolites and expression of drought-resistant genes to resist drought stress. The paper reviewed the research progress in the mechanism of plant response to drought stress from phenotypic level, physiological level and molecular level. The response of drought stress in phenotypic mainly included the structure change of root system and leaf. The response of drought stress to physiological was mainly reflected in photosynthesis, osmotic regulation, antioxidant metabolism and hormone, etc.. The paper elaborated in detail the molecular mechanism of plant drought stress response and regulatory and functional genes involved in drought stress, discussed the existing problems and look forward the research prospect. Related Articles | Metrics

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Codon Bias and Evolution Analysis of CqGAI in Chenopodium quinoa Yang FENG, Fenggen GUO, Shiyu WANG, Zhengjie LIU, Wenhong LONG Journal of Agricultural Science and Technology    2024, 26 (4): 27-36.   DOI: 10.13304/j.nykjdb.2023.0125 Abstract （208）   HTML （4）    PDF （4328KB）（894）       Knowledge map    Save To clarify the codon usage characteristics of CqGAI gene， the sequence of CqGAI gene was cloned. The codon usage preference of CqGAI gene was analyzed using CodonW， SPSS software and EMBOSS online program， and neutral mapping， ENC analysis and parity preference bias analysis were performed with GAI genes of 25 plants. The results showed that the length of coding sequence （CDS） of CqGAI gene was 1 782 bp， which encoded 593 amino acids， and contained the unique structural domains of DELLA gene family such as DELLA， TVHYNP， NLS， VHIID， LHR and RVER. The CqGAI gene could rapidly responded to gibberellines （GA），whichplayed a key role in the GA signaling pathway. Codon bias analysis showed that ENC， CAI and GC content of CqGAI gene were 54.14， 0.21 and 46.18%， respectively， with weak codon bias， preference ending with A/T and 27 high frequency codons. The clustering analyses showed that the CqGAI gene had the closest preference to Caryophyllales. The base composition and correlation analysis revealed that the codon preference of CqGAI gene was influenced by selection effect and base mutation. The frequency of codon usage indicated that both Escherichia coli and yeast were suitable for heterologous expression of CqGAI gene， and Arabidopsis thaliana， Nicotiana tabacum and Beta vulgaris were suitable for genetic transformation recipients for functional analysis of CqGAI gene. Above results provided an important reference for further study the function and heterologous expression of CqGAI gene. Table and Figures | Reference | Related Articles | Metrics

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Study on Leaf Traits and Adaptation Strategies of Sophora japonica at Different Ages Rongrong CHU, Guoqing FENG, Zhongyi ZHANG, Huijiao LIU, Jiaxin DONG, Zhangzhen WEN, Xiangbin GAO, Xiaoman XIE, Dan LIU Journal of Agricultural Science and Technology    2024, 26 (3): 48-56.   DOI: 10.13304/j.nykjdb.2023.0438 Abstract （250）   HTML （3）    PDF （1666KB）（771）       Knowledge map    Save The variation and correlation of leaf traits can reflect the resource utilization and adaptive survival strategies of plants. In order to explore the traits and variation rules of the leaves of Sophora japonica of different ages， taking the leaves of Sophora japonica of different ages in Liaocheng city as the research object， 13 indicators including the leaf area （LA）， leaf fresh weight （FW）， leaf dry weight （DW）， leaf length （LL）， leaf width （LW）， petiole length （PL）， leaf thickness （LT）， rachis length （RL）， leaf shape index （LI）， specific leaf area （SLA）， leaf dry matter content （LDMC） ， leaf tissue density （LTD）， and specific leaf weight （SLW） were measured， and one-way analysis of variance and coefficient variation analysis were used to explore the characteristics of leaf traits at different tree ages. Principal component analysis and correlation analysis were used to study the adaptation rules of Sophora japonica leaves at different tree ages. The results showed that the DW， LL and PL of reserve resources were significantly higher than those of other tree ages （P<0.01）. The total coefficient variations of 13 leaf traits of Sophora japonica were from 8.57% to 81.48%； among leaf traits of different tree ages， the coefficient variation of the reserve resource LTD was the largest which was 92.86%， and the coefficient variation of the secondary ancient tree LDMC was the smallest which was 5.84%. LA， FW， DW， LL and LW were extremely significantly positively correlated with each other （P<0.01）； SLA was significantly negatively correlated with FW， DW， LTD and SLW （P<0.01）， and positively correlated with LT（P<0.01）； LDMC was significantly positively correlated with FW， DW， LTD and SLW （P< 0.01）. The leaf traits of reserve resources had the characteristics of high LDMC and SLW， low SLA， and belong to the survival strategy of “quick investment-income type”； the secondary ancient trees and the first grade ancient trees showed high SLA， low LDMC and SLW leaf character combinations， and adopted a “slow investment-benefit” and “conservative” strategy. Above results provided a scientific basis for the formulation of maintenance and management strategies for different age classes of Sophora japonica. Table and Figures | Reference | Related Articles | Metrics

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Cloning and Expression Analysis of Wheat TaCOBL- 5 Genes Xinyue BAO, Hongmin CHEN, Weiwei WANG, Yimiao TANG, Zhaofeng FANG, Jinxiu MA, Dezhou WANG, Jinghong ZUO, Zhanjun YAO Journal of Agricultural Science and Technology    2024, 26 (6): 11-21.   DOI: 10.13304/j.nykjdb.2024.0172 Abstract （291）   HTML （22）    PDF （3595KB）（628）       Knowledge map    Save Wheat yield directly impacts food security in China， but various abiotic stresses such as drought， low temperature， salt and high temperature severely constrain wheat production. In previous analysis， transcriptomic data revealed differential expression of wheat TaCOBL-5D under multiple abiotic stresses. TaCOBL-5D and its homologous genes TaCOBL-5A and TaCOBL-5B were cloned and obtained， and the comprehensive bioinformatics and expression pattern were analyzed. The results showed that TaCOBL-5 genes exhibited significant conservation in gene structure， protein tertiary structure， conserved domains， and promoter regulatory elements with COBL genes from other species. TaCOBL-5 genes exhibited the highest expression level in roots and responded differently to various abiotic stresses， especially significantly down-regulated under drought stress， indicating its importance under drought stress； it also showed different responses to low temperature， high temperature， and salt stress. In addition， the expression level of the TaCOBL-5D gene varied significantly among different drought-resistant and high-temperature-resistant materials， further suggesting its important role in stress resistance. These findings laid the foundation for further understanding of the function of COBL genes in wheat and provided scientific support for wheat breeding efforts aimed at enhancing stress tolerance. Table and Figures | Reference | Related Articles | Metrics

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Whole Genome Sequencing of Multi-drug Resistant Escherichia coli and Its Drug Resistance Analysis Haili LI, Yindi XU, Zhifang WANG, Wenhao ZHU, Lixian ZHANG, Chunjiang MA Journal of Agricultural Science and Technology    2024, 26 (6): 113-121.   DOI: 10.13304/j.nykjdb.2023.0169 Abstract （496）   HTML （4）    PDF （4555KB）（895）       Knowledge map    Save In order to understand colistin resistance genes carried by Escherichia coli， screen sensitive plant drugs， and solve the dilemma of multiple drug resistance and no drug option in animal clinic， the resistance genes of Escherichia coli were identified by 16S rRNA sequencing and PCR. The antimicrobial susceptibility of 78 antibiotics were detected， and the bacteriostatic and bactericidal effects of 4 kinds of natural plant extracts （palmatine， berberine， baicalin and macleaya cordata） were tested. The results showed that 145 strains of E.coli were isolated and identified from intestinal tract of swine clinical diarrhea cases in 2021 （from January to December） and 2022 （from January to June）， and a clinical strain carrying colistin resistance genes （mcr-4，mcr-5） and β-lactamases blaTEM and AmpC was identified， which named HN2149. The antimicrobial susceptibility of 78 antibiotics showed that the HN2149 strains was sensitive to cefepime， cefodizime， fosfomycin， cefixime， meropenem， cefoxitin， cefazolin， cefoperazone， cefotaxime， ceftazidime， cefuroxime， ceftriaxone， aztreonam， piperacillin-tazobactam， ticacillin/clavulanic acid， cefoperazone sulbactam， ceftazidime/clavulanic acid， cefotaxime/clavulanic acid， ceftizoxime， cefmetazole， cefetamet， and was resistant to 57 antibiotics. The drug sensitivity of 4 plant extracts showed that the macleaya cordata had the best bacteriostatic and bactericidal effect on HN2149 strain， while the other 3 extracts had no effects on HN2149 strain. Above results provided reference for the prevention and control of swine colibacillosis. Table and Figures | Reference | Related Articles | Metrics

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Simulation and Optimization of Pneumatic Conveying System for Hybrid Rice Pollen Collection Device Fenfang XIAO, Conghe ZHANG, Hui WANG, Yafeng YE, Daolin ZHANG, Heting WANG, Bo LI, Yuejin WU, Binmei LIU Journal of Agricultural Science and Technology    2023, 25 (4): 110-122.   DOI: 10.13304/j.nykjdb.2022.0048 Abstract （201）   HTML （3）    PDF （4205KB）（815）       Knowledge map    Save In order to solve the problem of mechanized and efficient collection of paternal pollen of hybrid rice， a hybrid rice pollen collection device was designed and the pneumatic conveying system was simulated and optimized. Firstly， the computational fluid dynamics-discrete phase model （CFD-DPM） was established for pneumatic conveying system. Furthermore， the CFD-DPM and the response surface method were combined to optimize and verify the system，which took the inner diameter of the tube， the length and width of the inlet as factors，and the air flow uniformity and total pressure difference as indexes. The results showed that the inner diameter， the length of the inlet，the width of the inlet， the interaction of inner diameter and length， and the interaction between length and width had significant effects on the airflow uniformity and total pressure difference in the system.The two indexes increased with the increase of the inner diameter， the uniformity of powder absorption first increased and then decreased with the increase of length and width， and the total pressure difference increased with the increase of length and width. The optimal parameter combination of pneumatic conveying system was 200.00 mm inner diameter， 564.40 mm length and 192.48 mm width. Simulation of the optimized system structure showed that the variable velocity and total pressure difference of airflow velocity were 16.03% and 238.37 Pa respectively. The relative errors were 4.91% and 3.39%， respectively. Compared with the initial structure， the two indexes were reduced by 56.29% and 31.57% respectively， indicating that the optimization effect was obvious. This study provided a method for rapid optimization design of pneumatic conveying system of hybrid rice pollen collection unit， and the results could provide reference for optimization design of pneumatic conveying system of hybrid rice pollen collection unit. Table and Figures | Reference | Related Articles | Metrics

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Preparation and Application of Natural Polymer Flocculants Yangyang CAI, Xiuping TAO, Tong LI, Bin SHANG, Jianchao SONG, Lu LIU Journal of Agricultural Science and Technology    2023, 25 (10): 165-172.   DOI: 10.13304/j.nykjdb.2022.0419 Abstract （283）   HTML （2）    PDF （524KB）（820）       Knowledge map    Save Natural polymer flocculant is the focus of current research. The mechanism， type and characteristics of natural polymer flocculants were detailed introducted， and the progress of preparation technology， the application status of natural polymer flocculants， especially their application in the field of water treatment were summarized. In view of the current problems of the new flocculant， the future research focus and development direction were looked forward， which provided a reference for the in-depth research and practical application of the new flocculant. Reference | Related Articles | Metrics

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Cloning and Expression Analysis of GbWRKY53 in G. barbadense LI Jing1§, LIU Simin1§, CAI Lijing2, WANG Zhaoyu1, DONG Lijun1, Journal of Agricultural Science and Technology    2017, 19 (11): 15-21.   DOI: 10.13304/j.nykjdb.2017.0200 Abstract （308）      PDF （2061KB）（732）       Knowledge map    Save Verticillium wilt is known as cotton cancer. Identifying of disease resistance gene is the basis for cotton verticillium wilt resistant molecular breeding. WRKY transcription factors play important roles in regulating plant responses to various abiotic and biotic stresses. In this study, a WRKY transcription factor GbWRKY53 was cloned from sea island cotton Pima 90-53 with high resistance to verticillium wilt. Its open reading frame (ORF) was 999 bp, and encoded a putative WRKY group Ⅲ protein with 332 amino acids and contained one conserved WRKY domains and one HXC zinc finger structure. The gene structure analysis showed that GbWRKY53 contained 3 exons and 2 introns. Phylogenetic analysis showed that GbWRKY53 closed to GrWRKY53. The expression of GbWRKY53 gene increased firstly and then decreased, and the expression of 12 h was the highest after Verticillium dahliae treatment. The expression of GbWRKY53 increased significantly after SA induction for 8 h, and maintained at a high level to 24 h. After the induction of methyl jasmonate (MeJA), the expression of GbWRKY53 reached the maximum at 12 h and then decreased. The expression level of GbWRKY53 was significantly lower than that of salicylic acid at the same time. The expression of GbWRKY53 gene was only slightly increased after the induction of ACC. It could be concluded that GbWRKY53 gene involved in the complex plant signaling pathway, and played an important role in cotton stress response to Verticillium dahliae. Related Articles | Metrics

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Analysis of Bacterial Communities in Rhizosphere Soil of Continuous Cropping Flue-cured Tobacco Using 16S rDNA-PCR-DGGE GONG Zhixiang1, MA Xiaohan1, REN Zhiguang1, ZHU Jinfeng2,HUANG Yuanjiong3, WANG Mengmeng1, CHEN Zheng1, XU Zicheng1* Journal of Agricultural Science and Technology    2018, 20 (2): 39-47.   DOI: 10.13304/j.nykjdb.2017.0231 Abstract （521）      PDF （2939KB）（647）       Knowledge map    Save The bacterial colonies of soil samples were analyzed by PCR-DGGE technique in order to provide theoretical basis for controlling obstacles of tobacco continuous cropping. The results showed that soil bacterial community was rich in flue-cured tobacco mid-late growing period. There were differences in the structure of bacterial community in field soil by different continuous tobacco cropping, most of the bacterial types were common, and there were few unique bacterial types. The change of bacterial abundance in continuous cropping soil was very stable, and the continuous cropping increased the abundance of soil bacteria, and showed a tendency of firstly increasing and then decreasing. The dominant populations of rotation bacteria were stable in the field period, while the bacterial flora in continuous cropping soil had greater changes. The activities of bacteria in warm-curvae, acid bacillus door and corynebacteriaceae had strong impact on soil nutritional metabolism, the pathogens were increased, which was unfavorable for the growth and development of flue-cured tobacco. Different continuous cropping years had greater impacts on the soil bacterial population structure in flue-cured tobacco. The changes in bacterial population structure of flue-cured tobacco after continuous cropping could be one of the main reasons causing obstacles in flue-cured tobacco continuous cropping. Related Articles | Metrics

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Active Ingredients and Action Mechanism of Agricultural Plant Jiaosu Bing LI, Xiumin ZHU, Dai LI, Junxia DU Journal of Agricultural Science and Technology    2024, 26 (7): 156-165.   DOI: 10.13304/j.nykjdb.2023.0660 Abstract （344）   HTML （2）    PDF （618KB）（752）       Knowledge map    Save Agricultural plant Jiaosu is a product containing specific bioactive ingredients which is derived primarily from plants through microbial fermentation. It could be applied in agriculture， animal husbandry and soil improvement. Agricultural plant Jiaosu plays significant roles in enhancing crop yields， soil quality and pest resistance， making it a key player in the establishment of green ecological agriculture. In this paper， the classification， characteristics and various effective components of agricultural plant Jiaosu were briefly introduced； the positive effects on crop yield increase， antibacterial properties， soil enhancement and environmental protection of agricultural plant Jiaosu were summarized； the mechanisms were analyzed， the existing issues were identified， and the future development of agricultural plant Jiaosu was discussed. Reference | Related Articles | Metrics

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Research Progress on Endoplasmic Reticulum Stress/Unfolded Protein Response Caused by Herpesvirus Haiqing CAI, Wei WANG, Maoqin ZENG, Wenwen BI, Li CHEN, Qiandong ZHANG, Yang YUAN, Ming WEN Journal of Agricultural Science and Technology    2023, 25 (9): 131-139.   DOI: 10.13304/j.nykjdb.2022.0538 Abstract （635）   HTML （11）    PDF （1481KB）（1112）       Knowledge map    Save Endoplasmic reticulum is the main site of protein folding and post-translational modification in eukaryotic cells. It also participates in the regulation of Ca2+ and lipid storage and synthesis， and has important physiological functions. Herpesviruses is a class of enveloped DNA viruses. The synthesis and processing of its surface glycosylated envelope proteins depends on the endoplasmic reticulum. During virus replication， a large number of synthesized glycosylated envelope proteins are excessive in the endoplasmic reticulum. Accumulation causes endoplasmic reticulum stress （ERS）， which in turn leads to unfolded protein response （UPR）. Some herpesviruses may have evolved mechanisms to regulate the UPR to create an optimal egoistic environment for the replication process. When they replicate in host cells， they will cause related endoplasmic reticulum UPR signaling cascades， such as cell damage， inflammation， apoptosis， etc. In this paper， the mechanism of endoplasmic reticulum stress/unfolded protein response （ERS/UPR） response to viruses was reviewed， and the molecular mechanism and related signaling pathways of ERS caused by herpes simplex virus type Ⅰ， pseudorabies virus， marek virus， duck enteritis virus and other herpes viruses were expounded， which provided theoretical basis for the research and development of herpes virus-related vaccines and drug targets. Table and Figures | Reference | Related Articles | Metrics

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Effects of Melatonin on Seed Germination and Seedling Growth of Chaotian Pepper Under Drought Stress Qianya WEI, Xinqi LIN, Lamei LIANG, Zhongwei QIN, Yingzhi LI Journal of Agricultural Science and Technology    2024, 26 (4): 46-57.   DOI: 10.13304/j.nykjdb.2022.0893 Abstract （218）   HTML （5）    PDF （8331KB）（311）       Knowledge map    Save In order to improve the seed germination and seedling growth of Chaotian pepper under drought stress， 1， 5， 25， 50， 75， 100， 125， 150 μmol·L-1 of melatonin solution were used to initiate the treatment of Chaotian pepper seeds， and 10% PEG solution was used to simulate water stress， and the seed germination， seedling growth and physiological changes of Chaotian pepper were analyzed. The results showed that 100 μmol·L-1 melatonin solution significantly increased the germination potential， germination rate， germination index and vigor index of the seeds under drought stress， which were increased by 425.01%， 122.73%， 178.55% and 796.93%， respectively， compared with the seeds without initiation. 100 μmol·L-1 melatonin solution could significantly increase the plant length， root length， above ground height， fresh weight， root fresh weight， above ground fresh weight and plant dry weight of Chaotian pepper seedlings under drought stress，which were increased by 146.70%， 221.74%， 70.00%， 48.88%， 121.66%， 39.38% and 285.71%， respectively，compared with the seeds without initiation. Physiological analysis showed that the catalase （CAT） activity， ascorbate peroxidase （APX） activity， and soluble sugar（SS） content of seeds induced by 100 μmol·L-1 melatonin solution were the highest， while malondialdehyde （MDA） and hydrogen peroxide （H2O2） contents were the lowest. After germination of seeds induced by 100 μmol·L-1 melatonin under drought stress， the highest levels of peroxidase （POD） activity， CAT activity， APX activity， SS， soluble protein （SP）， and proline （Pro） contents were observed in the seedlings； MDA and reactive oxygen species （ROS） had the lowest content. Above results indicated that using 100 μmol·L-1 melatonin solution could induce the germination and growth of Chaotian pepper seeds under drought stress， which provided reference for drought resistant cultivation and breeding of Chaotian pepper. Table and Figures | Reference | Related Articles | Metrics

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Studies |of Mevalonate Pathway Influence on Biosynthesis of Terpenoids in Basidiomycota LI Liang1,2, SHANG Xiao\|dong1, TAN Qi1*    2014, 16 (3): 53-61.   DOI: 10.13304/j.nykjdb.2013.536 Abstract （595）      PDF （1488KB）（1428）       Knowledge map    Save There are numerous active terpenoids in Basidiomycota cellular. These active substances have important influence on human nutrition and health. Mevalonate pathway, which can govern biosynthesis of some kinds of terpenoids, is an essential path in regulating secondary metabolism in Basidiomycota cells. However, the production of terpenoids in the cell is very low, and the chemical and biological synthesis methods of active terpenoids are with low efficiency and high cost. Therefore, in order to increase the output of terpenoids substances, this paper introduced some key substances, Acetyl\|CoA, HMG\|CoA, MVK, and their influences on biosynthesis of terpenoids, aiming at improving target terpenoids production by adjusting and controlling these substances. Related Articles | Metrics

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Development and Verification of Prediction Model for Grape Downy Mildew Based on Machine Learning Fengxia BIAN, Kaige LIU, Xinmin RONG Journal of Agricultural Science and Technology    2023, 25 (8): 126-137.   DOI: 10.13304/j.nykjdb.2022.0866 Abstract （324）   HTML （8）    PDF （3217KB）（567）       Knowledge map    Save Grape downy mildew is one of the major diseases on grapes， which can occur from seedling to fruit maturity， often causing destructive losses in rainy years. To accurately predict the occurrence of grape downy mildew and minimize the hazards of grape downy mildew， based on the agrometeorological data and disease occurrence data during grape growth in 2020， a prediction model for the occurrence of grape downy mildew was developed by 4 machine learning algorithms （binary logistic regression， support vector machine， decision tree and K-nearest neighbors）， and the models were verified using the data in 2021. The results showed that the decision tree model had the best evaluation indicators in the disease prediction model， which the accuracy was 94%， and the precision， recall and F1-score was 91%， 90% and 91%， respectively. The decision tree model’s performance was still better than the other models using validation data. Therefore， the decision tree model could be further used to develop early warning systems for grape downy mildew， which should provide technical support and decision-making guidance for controlling it in production. Table and Figures | Reference | Related Articles | Metrics

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Research Progress on Frass After Organic Waste Transformation by Black Soldier Fly Jingwen QIANG, Wanqing WANG, Manyu TANG, Shuang WU, Wei HUA, Xinyue ZHU, Yanling CHENG Journal of Agricultural Science and Technology    2023, 25 (5): 158-167.   DOI: 10.13304/j.nykjdb.2022.0931 Abstract （496）   HTML （14）    PDF （862KB）（1281）       Knowledge map    Save At present， the annual production of organic waste in our country is about 4.5 to 5.0 billion tons， if its improper treatment will have a negative effect on the atmosphere， water body， soil and other aspects， thus causing secondary pollution for the environment. Black soldier fly larvae can effectively decompose organic solid wastes and convert them into marketable products in line with the concept of circular economy， and the frass produced in this process can be used as organic agricultural fertilizers， thus promoting the transition from traditional economic development to ecological circular economic model. However， the nutrient of frass， the composition of microorganisms and bioactive compounds， the post-treatment requirements to improve the biostability of frass， and the mechanism of frass in soil and plant metabolism are still unclear. Therefore， in order to improve the resource utilization of organic waste and promote sustainable agricultural development， this paper emphasized the potential of organic waste transformation by the black soldier fly， summarized the characteristics of frass and its effects on plant growth， and focused on the current application of frass as plant fertilizer. The promoting effect of this product on the development of modern ecological agriculture was pointed out， and put forward some research problems to be solved in the future. Table and Figures | Reference | Related Articles | Metrics

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Analysis of Differential Seed Metabolites Before and After Stratification of Heracleum moellendorffii Hance Yongfang ZHANG, Shiyan DONG, Jiaxuan WANG, Xuhu GUO, Chang ZHANG, Yanxing WANG, Yuye WANG, Jingfeng WU, Tianfang BAO, Hongfa ZHANG, Ping YU, Fuheng LI Journal of Agricultural Science and Technology    2024, 26 (7): 37-49.   DOI: 10.13304/j.nykjdb.2023.0183 Abstract （205）   HTML （4）    PDF （4918KB）（554）       Knowledge map    Save In order to deeply explore the seed dormancy mechanism of Heracleum moellendorffii Hance， the different metabolites of non-lamellarized seeds （NS） and germination seeds after lamellarization （GS） were analyzed by GC-TOF/MS （gas chromatography-time of flight mass spectrometry）. The results showed that a total of 995 metabolites were detected， and there was a clear separation between NS and GS. There were 126 differential metabolites， among which 75 were extremely significant differential metabolites including 35 up-regulated and 40 down-regulated expressions. The metabolic pathways of the extremely significant differential metabolites were analysed and 10 key metabolic pathways were identified. The results of the chord diagram analysis showed that the lipids （including lipid-like molecules） was extremely significantly positive correlaed with benzenoids， while the benzenepropanoids （including polyketides） was extremely significantly negative correlation with organoxides. Above results provided theoretical basis of metabolomics for exploring the post-maturation germination of Heracleum moellendorffii Hance seeds， and researching the post-maturation and dormancy mechanisms of Heracleum moellendorffii Hance seeds. Table and Figures | Reference | Related Articles | Metrics

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Effects of Manure Application on Soybean Yield and Soil Nutrients in China Chenyang ZHANG, Minggang XU, Fei WANG, Ran LI, Nan SUN Journal of Agricultural Science and Technology    2023, 25 (8): 148-156.   DOI: 10.13304/j.nykjdb.2022.0077 Abstract （388）   HTML （10）    PDF （1441KB）（644）       Knowledge map    Save Application of manure can increase soybean yield and soil fertility. There are significant differences in soybean yield and soil fertility in China due to the influence of region， application rate of manure， type of manure etc. However， the reasons for these differences are still not clear. In order to find out the effect of manure fertilizer application on soybean yield and soil fertility in different regions and management measures in China， and the main factors of yield increase effect， this study collected data on a national scale for integrated analysis. According to the searching criteria， 37 literatures including 119 groups of data on the effect of manure application on soybean yield and 11 literatures including 148 groups of data on the effects of manure application on soil nutrients were obtained. The enhanced boosted regression tree （BRT） model was used to quantify the importance of climate factors， soil properties and manure application measures on soybean yield increase. The average soybean yield increased by 12.9% after application of manure in different regions， with the highest yield in south China （18.7%） and followed by North China （14.8%）， Northwest China （13.6%） and Northeast China （12.0%）. When the application rate of manure was more than 5 000 kg·hm-2， the increase of soybean yield was 18.5%. Soybean yield increased by 24.9% after the application of cow manure， followed by the application of pig manure （17.6%）， commercial manure （15.3%）， chicken manure （12.7%） and manure （8.8%）. The average soybean yield was 2 224 kg·hm-2 with no fertilizer， whereas it increased by 20.4% to the amount 2 518 kg·hm-2 with applying manure alone. The average soybean yield was 2 259 kg·hm-2 under the application of chemical fertilizer， whereas it increased by 9.1% to the amount 2 558 kg·hm-2 under the combined application of manure and chemical fertilizer. Manure application significantly increased soil available P （43.5%）， total P （13.3%） and organic matter （11.0%）， but had no significant effect on soil available K （9.4%）， alkali hydrolyzable nitrogen （3.4%）， pH （2.1%） and total K （1.2%）. Based on the BRT results， the BRT model explained 52.83% of soybean yield differences in China. Among them， the application rate of manure had the greatest impact on soybean yield， accounting for 47.0% of the variation， followed by soil properties （41.0%） and climate factors （12.0%）. In general， the application of manure （including the single application of manure and combined application of manure and chemical fertilizer） could significantly increase soybean yield， with the largest increase in South China and with the highest increasing production benefit under the application of cow manure. Soybean yield was mostly affected by the application rate of manure. Additionally， the available P， total P and organic matter contents in soybean soil significantly increased under the application of manure. Table and Figures | Reference | Related Articles | Metrics

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Soil Nutrient Characteristics of Ulmus pumila L. Forest at Different Ages in Daqingshan Yuexin ZHANG, Yunxia MA, Xiuzhi MA, Jinwang ZHANG, Yuelin WANG, Haisheng YU Journal of Agricultural Science and Technology    2023, 25 (12): 168-176.   DOI: 10.13304/j.nykjdb.2022.0737 Abstract （140）   HTML （2）    PDF （651KB）（458）       Knowledge map    Save In order to reveal the change trend and law of soil enzyme activity and soil nutrients with forest age in Daqingshan Nature Reserve， 3 different forest ages （10， 25 and 40 a） at Ulmus pumila L. forest in Daqingshan were selected as the research objects， and a total of 8 indicators of soil pH， available nitrogen， available phosphorus， available potassium， organic matter， sucrose， catalase and polyphenol oxidase in the soil layer of 0—10，10—20，20—30 and 30—40 cm were measured. The characteristics and interrelationships of enzyme activity and nutrient content in soil of Ulmus pumila L. with different forest ages were analyzed. The results showed that with the increase of forest age， the content of soil organic matter and available potassium in soil of Ulmus pumila L. forests showed an upward trend； available nitrogen and available phosphorus were raised first and then decreased， and the soil pH was gradually reduced. With the deepening of soil depth， the contents of soil organic matter， available nitrogen， available phosphorus and available potassium all showed obvious surface aggregation. Peroxidase activity gradually decreased with the increase of forest age； the activities of sucrase and urease showed a tendency of increasing first and then decreasing， and the enzyme activity gradually decreased with the depth of the soil layer. There was a certain correlation between soil nutrients and enzyme activity， and there was a significant positive correlation between available nitrogen and available phosphorus and sucrase and urease （P<0.05）； there was a significant negative phase between available potassium and organic matter and catalase （P<0.05）. According to the principal component analysis results， the soil fertility of the soil layer of 0—10 cm in the 25 a forest age was the highest. The results of the study could provide scientifsic basis for sustainable management of Ulmus pumila L. forests and soil fertility enhancement. Table and Figures | Reference | Related Articles | Metrics

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Effect of Mixed Saline-alkali Stress on Leaf Structure and Photosynthetic Fluorescence Properties of Jujube Min YAN, Yan WANG, Chengcheng WANG, Songchao GUO, Dengyang LU, Cuiyun WU Journal of Agricultural Science and Technology    2024, 26 (3): 57-65.   DOI: 10.13304/j.nykjdb.2022.0865 Abstract （207）   HTML （6）    PDF （4292KB）（411）       Knowledge map    Save To further investigate the physiological response mechanisms of jujube to mixed saline-alkali stress， the experiment was conducted to simulate soil salinity stress by different concentrations of NaCl and NaHCO3 at full fruit period of Junzao， including 0， 60， 120， 180， 240 and 300 mmol·L-1. The changes of microstructure， ultrastructure， photosynthesis and fluorescence parameters of Junzao leaves under different stress levels were analyzed. The results showed that， with the increase of salt concentration， the leaf thickness， cuticle thickness， epidermal thickness and fenestrated tissue thickness of jujube showed a trend of increasing and then decreasing， and the thickness of spongy tissue and cell structure laxity gradually decreased. When salt concentrations was higher than 180 mmol·L-1， the number of osmiophilic particles in chloroplasts increased significantly， their size became larger， and the structure of stromal lamellae was loosened. Meanwhile， with the increase of stress level， net photosynthetic rate， stomatal conductance and transpiration rate gradually decreased， intercellular CO2 concentration increased， which indicated photosynthetic limitation was dominated by non-stomatal factors. Under high level treatments of 240 and 300 mmol·L-1， F0 significantly increased， while Fm， Fv/Fm， Fv/F0 significantly decreased， ABS/RC， TRo/RC and DIo/RC showed an overall trend of first decrease and then increase， and ETo/RC showed a continuous decreasing trend. In conclusion， higher saline-alkali stress could cause significant changes in the ultrastructure of Junzao leaves， inhibite the photosynthetic capacity， increase the size and number of osmiophilic vesicles， and appear the starch grains， which provided a theoretical basis for the in-depth study of the salt tolerance mechanism of jujube. Table and Figures | Reference | Related Articles | Metrics

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Optimization of Compound Enzymolysis Process of Dried Figs by Plackett-Burman Design and Response Surface Methodology DAI Yangjun1, HU Jian1,2, ZHOU Ying2, ZUO Bo1, SHI Yixue1 Journal of Agricultural Science and Technology    2018, 20 (7): 146-153.   DOI: 10.13304/j.nykjdb.2017.0888 Abstract （281）      PDF （5834KB）（743）       Knowledge map    Save In order to explore the optimum technology parameters for composite enzymatic hydrolysis of dried figs, this paper evaluated 7 factors affecting composite enzymatic hydrolysis of dried figs by Plackett-Burman design based on single factor experiment. And 3 significant factors including pectinase additive amount, cellulase additive amount and acid protease additive amount were screened out. Then, the paper further optimized by Box-Behnken design the optimal parameter level of main influencing factors. The results showed that the optimal composite enzymatic hydrolysis for dried figs was 0.66‰ complex phosphosesterasum additive amount including 0.25‰ pectinase, 0.25‰ cellulase and 0.16‰ acid protease, with solid-liquid ratio 1∶20, enzymolysis pH 4.0, enzymolysis temperature 50℃, and 40 min enzymolysis time. Under these technology conditions, the content of soluble solids in enzymatic hydrolysate was 7.73°Bx. The efficiency of enzymatic hydrolysis was significantly improved. Related Articles | Metrics

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2003, 5 (6): 40-43.   Abstract （702）      PDF （202KB）（2128）       Knowledge map    Save Related Articles | Metrics

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Identification and Characterization of IPT Gene Family in Brassica rapa L. Bo LIU, Wangtian WANG, Li MA, Junyan WU, Yuanyuan PU, Lijun LIU, Yan FANG, Wancang SUN, Yan ZHANG, Ruimin LIU, Xiucun ZENG Journal of Agricultural Science and Technology    2024, 26 (2): 56-66.   DOI: 10.13304/j.nykjdb.2022.0373 Abstract （215）   HTML （5）    PDF （4158KB）（469）       Knowledge map    Save Isopentenyltransferase （IPT） is the first limiting enzyme for cytokinin biosynthesis， so to analyze the function of the IPT gene family in Brassica rapa L.， a total of 13 BrIPT genes were identified from the genome of Brassica rapa L. by bioinformatics， which were heterogeneously distributed on 7 chromosomes. These BrIPT genes were divided into 4 substrates and each BrIPT gene included 8~10 conserved motifs and 1~2 UTR regions. The promoter regions of BrIPT genes contained numerous responsive elements. The BrIPT genes were regulated by environmental factors， biohormones， defense and stress. The qRT-PCR results showed that the tRNA-IPT genes BrIPT4， BrIPT6 and BrIPT9 were expressed in various parts of Brassica rapa L.. The expressions of IPT genes in Brassica rapa L. were higher at the mature stage than those at the seedling stage. The above results provided some basis for subsequent in-depth studies on the physiological and biochemical functions of IPT gene family members. Table and Figures | Reference | Related Articles | Metrics

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Research Progress on Nutritional and Health-care Functions and Molecular Mechanism of Royal Jelly SHEN Li-rong, ZHANG Li-wen, DING Mei-hui, et al.    2009, 11 (4): 41-47.   Abstract （1336）      PDF （691KB）（1514）       Knowledge map    Save Royal jelly, an important honeybee product, is not only nutritional food regulating the development and case differentiation of honeybee, but also a health-care product with very effective activities for animal and human health. This paper introduces the active components, total composition and nutritional and healthy functions of main active components, such as 10-hydroxy-2-decanoic acid, proteins and peptides of royal jelly. It also introduces the research progress made in molecular mechanism related to lifespan and fertility. According to the internal and external new research trends, it puts forward related suggestions as paying attention to basic research on royal jelly, developing deep process and biological engineering industry of royal jelly. Related Articles | Metrics

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Status of Development and Countermeasures on Utilization Technology of Antarctic Krill Resources in China YUE Dong-dong, WANG Lu-min*, HUANG Hong-liang, ZHENG Han-feng, FENG Chun-lei, ZH    2015, 17 (3): 159-166.   DOI: 10.13304/j.nykjdb.2015.041 Abstract （497）      PDF （1153KB）（987）       Knowledge map    Save Development and utilization of Antarctic krill resources are gaining international concern with each passing day. With gradually matured Antarctic krill fishing and processing technology, changes in development strategies of Antarctic krill resources at different countries have taken place. This paper analyzed the technical bottleneck existing in the development and utilization of Antarctic krill resources, and briefly reviewed the progress made in independent design, R & D of krill fishing equipment, and preparation of krill meal and krill oil. By analyzing Antarctic krill patent application information, it was believed that at present the domestic R & D major bodies had paid much attention to the preparation and production processes of krill oil and feed, while the international world had transferred their R & D and patent application focuses to pharmaceutical field. Facing the strategic demand of developing marine living resources, we shoud accelerate the process of design and construction of specialized vessels for Antarctic krill fishing and processing, and at the same time improve the processing technology and patent layout of Antarctic krill, so as to provide technical support and assurance for taking over and exploiting krill consumer market. Related Articles | Metrics

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Progress on Pullulanase Gene Engineering LV Jin-zhi1,2, TIAN Jian2, WU Ning-feng2, CHU Xiao-yu2*, ZHANG Feng-ying1*    2015, 17 (4): 85-91.   DOI: 10.13304/j.nykjdb.2015.090 Abstract （409）      PDF （1511KB）（614）       Knowledge map    Save As a starch debranching enzyme, pullulanase can specifically hydrolyze α-1,6 glucosidic linkages in polysaccharide and change amylopectin into amylose.  Combinating with other amylases, pullulanase is mainly used in food processing industry taking starch as raw material. It can improve starch utilization rate and production efficiency by a large scale. At present,  pullulanases have been expressed in E. coli, Bacillus sp. and Pichia pastoris expression system. However, these expression levels are hard to satisfy the requirement of industry production. This paper summarized the latest research progress made in recent years from the aspects of  heterologous expression, optimization of pullulanase, and molecular modification of enzym protein, so as to lay a solid foundation for searching more effective way to improve  pullulanase expression quantity. Related Articles | Metrics

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Present Status and Future Prospect for Potato Industry in China YANG Yalun, GUO Yanzhi, SUN Junmao* Journal of Agricultural Science and Technology    2017, 19 (1): 29-36.   DOI: 10.13304/j.nykjdb.2016.202 Abstract （714）      PDF （1130KB）（1390）       Knowledge map    Save With the development of taking potato as staple food strategy, potato has been one the of the 4 staple grain crops in China. Potato industry is playing an important role in ensuring food security, preserving ecological environment, etc.. This paper summarized the current development of potato industry in production, consuming and processing; analyzed the existing bottleneck issues in seed industry and processing industry and mechanization, etc.; prospected the future development of potato industry in China combining the development experience of international potato industries. In the future, the demand quantity for potato, and the proportion between yield and processing would definately increase and also the processing industry degree of aggregation will increase. Related Articles | Metrics

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Extracting Method of Hemochrome and Its Application in Meat Products LUO Zhang, ZHENG Li-hong    2006, 8 (1): 40-42.   Abstract （713）      PDF （153KB）（1800）       Knowledge map    Save In this paper, chemical structure, physical and chemical property, extracting method and application of hemochrome in meat products were summarized, and nutritional value of hemochrome was also disccussed. Related Articles | Metrics

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Temporal and Spatial Variation of Xinjiang Natural Grassland and Their Responses to Climate Factors Weikang ZHAO, Changqing JING, Chen CHEN Journal of Agricultural Science and Technology    2023, 25 (7): 197-206.   DOI: 10.13304/j.nykjdb.2021.0931 Abstract （180）   HTML （5）    PDF （4986KB）（436）       Knowledge map    Save Based on remote sensing data such as net primary productivity （NPP）， normal difference vegetation index （NDVI） and climate factors （temperature and precipitation）， the temporal and spatial variation of grassland NPP and grassland NDVI in Xinjiang and their responses to climate factors were analyzed by the unary linear regression model， correlation analysis and other methods. The results showed that the annual average values of grassland NPP and NDVI both showed an upward trend. The spatial distribution of grassland NPP over the years showed a trend of high in the north and low in the south， and the spatial distribution of grassland NDVI showed a trend of gradually decreasing from northwest to southeast. From 1985 to 2015， the average annual temperature and precipitation both showed an upward trend. Overall， the average annual temperature in the basin was higher than that in the mountainous area， and the average annual precipitation in the mountainous area was more than that in the basin. From the perspective of spatial correlation， whether it was grassland NPP or grassland NDVI， the area of grassland positively correlated with precipitation was larger than that of grassland positively correlated with temperature， and the correlation coefficient with precipitation was higher than that with temperature. It showed that precipitation was the main influencing factor of grassland vegetation in Xinjiang， which deepened the understanding of Xinjiang grassland’s response to climate factors and provided data support for the response to climate change. Table and Figures | Reference | Related Articles | Metrics