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- Abstract：In order to analyze the genetic rule of maize doubled haploid(DH)population, the ‘Xianyu 335' DH population was used for genotyping with the Maize6H-60K array, and the molecular markers were screened and corrected with a developed accurate strategy. The results showed that: 1)A total of 18 947 clustered SNP markers covering the whole genome of maize were obtained by eliminating monomorphic, heterozygous and the missing data with the accurate genotyping strategy. 2)The average recombinant frequency of ten chromosomes was 1. 84-1. 03 in the ‘Xianyu 335' DH population. The recombination frequency in the satellite region of chromosome 6 was significantly reduced. 3)There was obvious segregation distortion on chromosome 1, 2, 3 and 8 in this population; through higher recombinant frequency and denser in the telomere regions of each chromosome, an tendency of returning to 50% of the theoretical segregation coefficient was discovered. The obtained recombination exchange and separation rules can be used to improve the accuracy of screening prospective breeding materials from DH population.Keywords：SNP gene array;double haploid population;genotyping;recombination exchange;segregation distortion19|12|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to explore the vertical distribution characteristics and remote sensing inversion of nitrogen content in maize leaves under different film mulching and irrigation levels, a field experiment was carried out at the National Field Scientific National Field Scientific Observation and Research Station on Efficient Water Use of Oasis Agriculture in Wuwei of Gansu Province in 2020. A total of three irrigation levels(100%(W100), 70%(W70)and 40%(W40))of spring maize irrigation requirement and three mulching treatments(non-mulching(M0), ordinary plastic film(M1)and degradable film(M2))were designed. The vertical distribution of leaf nitrogen content, canopy reflectance and leaf nitrogen content of spring maize under different irrigation and film mulching conditions were measured by Kjeldahl method and hand-held ground object spectrometer. The results showed that: Under different mulching treatments, the nitrogen content in maize canopy leaves of non-mulching treatment was in the order of non-mulching treatment(M0)>biodegradable film(M2)>ordinary plastic film(M1). Under the same mulching condition, the more irrigation amount, the higher leaf nitrogen content. Under the same treatment, nitrogen content in different vertical parts of maize canopy decreased from top to bottom. Under the same mulching condition, canopy reflectance decreased with the increase of irrigation amount in the range of visible light band. Within the near infrared band range, canopy reflectance increases with the increase of irrigation amount. The estimation model of leaf nitrogen content in different vertical parts of spring maize based on random forest was consistent with the actual measurement. The estimation accuracy of nitrogen content in the upper leaves were the highest, followed by the middle leaves, and the lowest in the lower leaves.Keywords：leaf nitrogen content;vertical distribution;random forest;spring maize;hyperspectral24|16|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to optimize the cultivation space of cassava maize intercropping system, a total of five different modes, including equidistant row sole cassava(MS1), wide-narrow row sole cassava(MS2), equidistant row cassava intercropping 1 row maize(MI1), wide-narrow row cassava intercropping 1 row maize(MI2), wide-narrow row cassava intercropping 2 rows maize(MI3)were set up. Then the aboveground agronomic traits and the yield of cassava and maize were measured, the storage root configuration(SRC), flesh quality of cassava root, and the soil physicochemical properties were investigated. The results showed that: Compared with MI1 and MI2, MI3 increased maize plant height by 9. 5% to 11. 5%, stem diameter by 14. 4% to 18. 1%, the maize total ear number by 45. 1% to 59. 7% and the fresh ear yield by 70. 9% to 76. 4%. Compared with cassava monoculture, a “competition-recovery-transcendence” phenomenon was existed in cassava-maize-intercropping(C-M-I)system, and C-M-I also increased the cassava yield of fresh storage root(FSR)by 31. 4% to 56. 2%, dry storage root by 34. 7% to 58. 4%, starch by 37. 5% to 60. 1%, as well as significantly increased the harvest index(HI)by 35. 1% to 40. 5%. The increase of the MI3 treatment was the largest. The half width along the ridge direction and across the ridge direction or depth of SRC were 30. 2-36. 2 cm, 20. 6-26. 4 cm, 22. 5-24. 7 cm, respectively. Furthermore, about 95. 1%-98. 5% of the number of storage root(NSR)and 98. 1%-99. 8% of the weight of storage root(WSR)were distributed within 0-40 cm along the ridge direction, ≥86. 9% NSR and ≥97. 2% WSR were distributed within 0-30 cm across the ridge direction, and 93. 7%-99. 2% NSR and 97. 6%-99. 9% WSR were distributed under 0-25 cm soil. SRC of MI3 displayed the widest and deepest distribution. There was no significant difference among all treatments with the flesh quality and taste of cassava root. The soil physicochemical properties after cassava harvest showed that C-M-I was better than cassava monoculture, wide-narrow row was better than equal spacing and among them MI3 was the best. Overall, MI3 has the greatest advantages in the above-ground growth, SRC, yield and soil physicochemical properties, so it is recommended to be popularized and applied in cassava production of Hainan.Keywords：cassava;maize;intercropping;storage root configuration;interaction20|17|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To investigate the effect of arbuscular mycorrhizal fungi(AMF)on the growth of wheat(Triticum aestivum L. ), a total of 6 main wheat varieties planted in Hebei Province from 1977 to 2011 were selected. The experiment was carried out in low phosphorus(P)soil(Olsen-P 4. 5 mg/kg), and the soil was treated with benomyl(+B)and without benomyl(CK). The field experiment with two-factor(6 varieties×2 benomyl levels)was set up. After harvest, the root mycorrhizal colonization rate in wheat was determined. The agronomic traits and physicochemical indexes of above- and below-ground parts of wheat were also measured. The results showed that: Under low P stress in the field, the mycorrhizal colonization, P content and leaf area of 6 wheat varieties were significantly changed by 17. 33%-83. 85%, -5. 36%-18. 02% and -5. 74%-30. 39% under +B treatment compared with those in CK, respectively; The shoot dry biomass of 6 wheat varieties was significantly changed by-26. 78%-16. 27% under +B treatment compared with that in CK. In addition, the root traits of wheat such as root length, root-shoot ratio and A-Pase activity were changed by 4. 36%-27. 23%, -4. 50%-45. 75% and 10. 14%-21. 49% under +B treatment compared with those in CK, respectively. Under low P stress in the field, the whole analysis of 6 wheat varieties showed that eight groups of below-ground traits were significantly correlated in CK, and 12 groups of below-ground traits were significantly correlated in +B treatment. The correlation of below-ground traits in +B treatment was increased by 50% compared with that in CK. In conclusion, under low P stress, the AMF colonization of 6 varieties wheat seedlings without benomyl(CK)was significantly higher than that in treatment with benomyl(+B), and the A-Pase activity of wheat root was significantly higher than that in +B treatment. The P content in shoot of other 5 varieties wheat except ‘Beijing 13' was higher than that in +B treatment. The root length of wheat in +B treatment was lower than that in CK, and root-shoot ratio of other 5 varieties wheat except ‘Shimai 15' was lower than that in CK, and the correlation of wheat below-ground traits was significantly increased. In conclusion, under low P stress in field condition, the mycorrhizal colonization of wheat roots increases, leading to the increase of the A-Pase activity of rhizosphere soil, the root length and root-shoot ratio, and thereby the increase of shoot P content, which is conducive for the growth of wheat at seedling stage.Keywords：low phosphorus stress;wheat varieties;benomyl;arbuscular mycorrhizal fungi;root traits17|15|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to clarify the molecular mechanism of microRNA(miRNA)and its target genes regulating plant root growth and development, related literature published in PubMed, Web of Science and CNKI from 1993 to 2021 with “miRNA”, “plant” and “root” as keywords were retrieved. Data obtained was sorted and summarized to analyzed regulation mechanism of miRNA and its target genes in plant root. The results showed that: 1)Many miRNAs and their target genes were involved in the regulation of root growth and development, which was a complex and highly ordered biological process. 2)MiRNA can cut target gene transcription or inhibits its translation through complementary pairing. It regulates the genes expression related to root growth and development at post-transcriptional level. 3)MiRNA-mediated regulation play an important regulatory effect in primary root growth, lateral root formation, adventitious root development, root structure, vascular bundle morphology, plant hormone induction, biotic and abiotic stress response on root growth and development.Keywords：miRNA;target genes;plant;regulation;root17|18|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To identify CsYABBYs family in cucumber and explore the biological function of CsYAB1a gene preliminarily, CsYABBYs genes were identified by BLASTp homology comparison. Analysis on gene and protein sequence and chromosomal localization also was performed, then their spatio-temporal expression patterns were detected by RT-qPCR and in situ hybridization. CsYAB1a gene was overexpressed in Arabidopsis, and transgenic lines' expression level and phenotype were analyzed. The expression level of CsYAB1a gene was measured after treated with different kinds of hormones. The results were as follows: 1) CsYABBYs family consists of 8 members, all of which contain the C2C2 zinc finger and YABBY domain; Most of the YABBYs genes were expressed in reproductive organs, CsYAB1a gene was mainly enriched in petal primordium and ovary exocarp and showed the polar pattern of distal expression. 2)In Arabidopsis, heterologous overexpression of CsYAB1a gene resulted in phenotypes including malformed pistils and stamens, shorter siliques and elongated distal curling leaves; CsYAB1a gene regulates the development of fruits and leaves and affects the expression levels of fruit development genes AtSPL, AtIND, and AtHEC and leaf polarity genes AtAS1 and AtKANs. 3)The promoter of the CsYABBYs gens contains five hormone response elements, and both CsYAB1a and CsCRC genes responded to exogenous abscisic acid and auxin spraying treatments. In conclusion, CsYABBYs family might play essential roles in the vegetative and reproductive growth of cucumbers, and CsYAB1a gene may involve fruit and leaf development.126|35|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to comprehensively understand the nutritional value of passiflora, this paper started from the current research and development status of the nutritional quality of passiflora. The research results on nutrition composition, bioactive substances, and their application to passionflower are sorted. This review focuses on the influencing factors of quality and the composition of quality in passionflower summarizes. The synthesis and metabolic processes of secondary metabolites are summarized, the effects of planting varieties cultivation environment, nutrient regulation, harvesting time, storage conditions and the processing methods on the nutrient quality of passionflower are analyzed. The passionflower application in ornamental value, environmental restoration, food processing, and medical value development are also summarized. It is found that the passionflower is rich in nutrition and medicinal value, which has great development and utilization value in the fields of food, medicine and cosmetics. It is suggested to vigorously promote the development of passionflower and scientific research investment in the whole industry chain.Keywords：passionflower;nutritional component;bioactive compound;functional component27|26|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To clarify the color traits of Royal Horticultural Society Color Chart(RHSCC), a commonly used tool in plant color testing, and its scientific application in determination of flower colors, this study focused on the 884 colors of RHSCC and flower colors of 150 potted carnation varieties, and conducted the color testing with the aid of colorimeter-mediated digital measurement and RHSCC-mediated visual measurement, and completed the color analysis taking advantage of statistics and color difference formula. Our results showed that: the 884 colors of RHSCC mainly distribute in the color spaces with high lightness, redness and yellowness; two-dimensional distribution of a* and b* concentrate in quadrant I and II; minimum values of color difference of 60 colors(between two colors)are 0. 50-1. 50, among which, 4 colors belong to different UPOV(International union for the protection of new varieties of plants)color groups. Results of RHSCC-mediated visual measurements indicated that, among the 150 potted carnation varieties, flower colors of 47 varieties were difficult to be matched with suitable RHSCC colors(values of color difference between flower colors and its similar RHSCC colors>6. 00); flower colors of some varieties can be matched with 2 RHSCC colors(values of color difference between the matched 2 RHSCC colors<3. 00). Results of variety grouping in view of RHSCC-mediated visual measurements illustrated that, color interval of pink group was too large, while white and dark purple group had small intervals; groups of yellowish green, yellow and green were difficult to be distinguished in terms of their color threshold values; outlier colors were common in most color groups. In conclusion, defections of RHSCC in flower color testing need to be considered, including color differences between several colors are too small to be distinguished for human eyes; Measurement accuracy is low due its color coverage is limited; Visual measurements are difficult to apply in effective variety grouping.Keywords：RHSCC;potted carnation varieties;flower color testing and grouping;color space;value of color difference23|15|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to understand the process of metabonomics in ruminant nutrition and metabolism research in recent years, and provide reference for the wide application of metabonomics in the research field, this paper summarized the literature and based on the introduction, classification and application scope of metabolomics. The application of metabolomics in rumen, blood and animal products of ruminants in recent five years was introduced to elucidate more mechanisms of nutrient metabolism in the body by taking advantage of the research advantages of metabolomics. The results showed that: 1)Metabonomics can comprehensively explore the process of nutrition utilization and transformation from a more basic level, which greatly promotes the development of ruminant nutrition. 2)Rumen metabolomics has developed rapidly. At present, the main research focuses on rumen acidosis, efficient utilization of nutrients and the regulatory mechanism affecting production performance. 3)Blood metabolomics is mainly used to discover biomarkers that reflect nutritional metabolism status and affect production performance. 4)Metabolomics provides a more comprehensive reference for improving milk and meat yield and quality. In view of the above research status, the limitations and future development direction of the current application of metabonomics are proposed as follows: A single detection method may not be able to obtain a very comprehensive metabolite information; Qualitative and functional database standards are unified; The combination of un-targeted and targeted metabolomics may be more reliable; Complex data need to be fully analyzed by bioinformatics etc. The integration and mutual complementation of multiple omics techniques is a new trend in nutrient metabolism research.Keywords：metabolomics;ruminants;nutrition;rumen;bleed;research progress24|18|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to compare the differences in the nutrient composition characteristics of donkey milk, horse milk, human milk, cow milk and goat milk, and understand the current development status of donkey milk, this paper collated relevant literature and made a summary and analysis. The results show that: 1)Donkey milk is the closest to human milk. Compared with cow and goat milk, donkey milk has the characteristics of high lactose, low protein, low fat, balanced calcium to phosphorus ratio, rich VC and VD. High lysozyme content is the greatest feature of donkey milk. Donkey milk has a high proportion of whey protein and it is rich in n3-PUFA and n6-PUFA, which are beneficial to the human body. Donkey milk is similar to horse milk, however, donkey milk has lower protein content and is closer to human milk. Compared with human milk, donkey milk has a lower fat content. 2)Donkey milk has biological activities such as antibacterial, anti-inflammatory, antioxidant, anti-tumor, prevention and treatment of cardiovascular diseases, etc. At the same time, it has good processing characteristics and is widely used in the history of various countries. Donkey milk has broad application value and market potential. However, there are still deficiencies in the technology, scale and market of donkey milk development, and there is a wide space for development. Realizing the scale of the industry, expanding the feeding volume, increasing the milk production and establishing and improving the industry standards as soon as possible are the problems that need to be considered and solved to realize the potential of the donkey milk market. To sum up, donkey milk has high nutritional value and rich biological activity. Its market potential is huge but its development is relatively lagging behind, and its research, development and promotion need to be strengthened.Keywords：donkey milk;nutritional components;biological activity;development prospects10|14|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to study the effect of amphiregulin(AREG)on glucose metabolism of sheep cumulus cells(CCs), cumulus-oocyte complexes(COCs)from medium and small antral follicles were collected. The fluorescent quantitative PCR was used to detect the expression of genes related to glucose metabolism in cumulus cells. AREG was added for in vitro culture of cumulus cells and in vitro maturation(IVM)of oocytes. The proliferation of cumulus cells was detected. The contents of glucose, lactic acid, NADPH and ATP in culture medium or cells were determined. The results showed that 1)The mRNA expression of G6PDH, PFKL and PFKM and the cell proliferation ability of cumulus cells derived from small antral follicles were significantly lower than those of cumulus cells from medium antral follicles(P<0. 05). 2)Lower concentration(10 ng/mL)AREG significantly increased the proliferation of cumulus cells from medium antral follicles(P<0. 05)but had no effect on cumulus cells from small antral follicles(P>0. 05). Under the synergistic effect of growth differentiation factor 9(GDF9)and bone morphogenetic protein 15(BMP15), 10 ng/mL AREG significantly increased the proliferation of both(P<0. 05), and there was no significant difference between them(P>0. 05). 3)AREG+GDF9+BMP15 significantly increased glucose consumption, lactate production, NADPH production in cumulus cell culture medium and ATP content of cumulus cells from different diameter antral follicles(P<0. 05). 4)The addition of AREG+GDF9+BMP15 added to the IVM medium of small antral follicular oocytes significantly increased the glucose consumption and lactic acid production in the culture medium and ATP content in cumulus cells(P<0. 05), and it was significantly higher than that of medium antral follicles(P<0. 05). The NADPH production and ATP content of oocytes were significantly increased(P<0. 05)and there was no significant differences compared with the medium antral follicular oocytes(P>0. 05). In summary, under the synergistic effect of GDF9 and BMP15, AREG can enhance the glucose metabolism of sheep cumulus cells. Also for IVM, adding the combination of AREG, GDF9 and BMP15 to the COCs culture medium of small antral follicles can make their glucose metabolism reach the same level of medium antral follicles.Keywords：cumulus cells;AREG;glucose metabolism;sheep;small antral follicles8|15|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aims of this study were to analyze the differentially expressed miRNAs and regulatory networks of Haemonchus contortus albendazole-resistant strains before and after albendazole administration by miRNA sequencing technology, to obtain the full miRNA expression profiles and drug resistance-related differentially expressed genes and miRNAs, and to explore the differences of DE miRNAs before and after Albendazole administration in H. contortus resistant strains. Small RNA-seq sequencing was performed on the Illumina Hiseq2000 platform for the pre- and post-administration of albendazole-resistant strains of H. contortus. The raw data were compared and analyzed with the reference genome and miRBase database. The miRNA target genes were predicted, and the miRNAs with significant differences in expression before and after administration of the transthyretin nematode resistant strains were screened and validated by stem-loop qRT-PCR. The miRNA-mRNA regulatory relationships with significant differences were visualized and analyzed using Cytoscape software. The target genes were mapped to KEGG and GO authoritative databases to predict and analyze the functional annotation of target genes and the pathways involved in regulation. The results showed that: 1)A total of 188 miRNAs with significantly differentially expression were screened before and after administration of albendazole-resistant strains of C. twistedus, of which 125 were up-regulated and 63 were down-regulated. The qRT-PCR results were consistent with that of transcriptome sequencing. 2)The 144 miRNAs significantly differentially expression were associated with 353 miRNA-mRNA negative regulatory relationships. Forty-six GO functions items and 327 pathways such as metabolism, transportation and degradation were annotated. 3)The screened candidate genes were mainly enriched in ABC transporter protein, HIF-1 signaling pathway, cGMP-PKG signaling pathway and P450 drug metabolism pathway, which confirmed the involvement of Haematobium twisted spear nematodes in drug resistance regulation mainly through metabolism and transport under the influence of drug stress. This study provides a reference for the screening of molecular markers for drug resistance diagnosis and the influencing factors and mechanisms of drug resistance regulation in H. contortus.Keywords：Haemonchus contortus;albendazole;drug resistance;transcriptome;miRNA4|15|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to develop fermenting agents with both decay promotion and nitrogen retention functions, the effects of different ratios of agents on the decay of rabbit manure and sesame oil cake compost and the conversion and loss of carbon and nitrogen were investigated. In this experiment, two kinds of self-made bacterial agents, cellulose degradation composite bacterial agent and functional bacterial agent, were used as the research objects. Closed aerobic composting experiment was carried out, and six treatments were set up: no bacterial agent(CK), EM commercial microbial agent(EM), only self-made cellulose degradation composite bacterial agent(CR), V (functional bacterial agent)∶V(self-made composite bacterial agent)=1∶1 ratio(CAR1), V(functional bacterial agent)∶V(self-made composite bacterial agent)=1∶2 ratio(CAR2)and V(functional bacterial agent)∶V(self-made composite bacterial agent)=1∶3 ratio(CAR3). The effects of the treatments on the fermentation parameters, carbon and nitrogen losses, nutrient content, maturity and other related indicators of the piles were investigated during the decomposition process. The results showed that during the start-up of composting, the temperature of CAR3 pile heated up quickly and the pH level was suitable, which was beneficial to aerobic fermentation. At the end of composting, the degradation rate of organic matter of CAR3 was as high as 34. 17%. However, the CO2 emission of CAR3 was 13. 43% lower than that of CR. In addition, the total humic acid production of CAR3 reached 15. 52%, which was 11. 92% higher than that of CR. The total nitrogen content in the pile was significantly increased, and the ammonia volatilization was 10. 28% lower than that of CK. At the same time, the organic nitrogen content of CAR3 was significantly increased by 19. 74% compared with CK, which was beneficial to nitrogen retention. In conclusion, when the ratio of V (functional bacterial agent)∶V (self-made composite bacterial agent)=1∶3(CAR3), it can significantly improve the maturity of compost, promote carbon conversion and reduce nitrogen loss. This study can provide a basis for the research and development of efficient spoilage and nutrient loss reduction fermentation agents for rabbit manure composting.Keywords：rabbit manure composting;carbon emission;ammonia emission;maturity;compound bacterium agent;ammonia assimilation16|15|10<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aims of this study were to investigate the effect of the artificial combination of composite strains in degrading lignocellulose and the characteristics of microbial community changes during the degradation process. A natural composite strains PLC-8 was firstly isolated and purified, and then five bacteria strains and two fungi strains were combined to construct three simplified composite strains, which were F1, F2, and F3, respectively. Straw degradation experiment was designed to determine the characteristics of microbial community changes in the process of cellulose decomposition by using DGGE method and related physicochemical analysis. The results showed that: The artificial combination of complex strain F3 had the strongest ability to decompose lignocellulose, and the average weight loss of straw was 39. 80%, hemicellulose decreased by 52. 64%, cellulose decreased by 25. 8%, and lignin decreased by 6. 26% within 30 d of decomposing lignocellulose. The activities of cellulose endonuclease, cellulose exonuclease, filter paper activity, β-glucosidase and xylanase reached the highest values for the whole decomposition process on day 15, which were 0. 09 U/mL, 0. 08 U/mL, 0. 09 U/mL, 0. 07 U/mL, and 0. 11 U/mL, respectively. The complex strains F3 was able to self-regulate pH, thus it could change the pH of the solution from weak acidity to weak alkalinity. Therefore, the microbial community of F3 showed a stable coexistence of fungi-bacteria and was able to maintain stability for a long time. In conclusion, the artificial combination of complex strains F3 is a stable and efficient lignocellulose-degrading complex microbial system.Keywords：lignocellulose;complex strain system;artificial combination;biodegradation8|12|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To investigate the effects of cotton straw returning and organic fertilizer application on the soil chemical properties and microbial quantity of continuous cropping cotton field, four treatments, e. g. , nitrogen and phosphorus fertilizer+straw stubble removal(NP), nitrogen and phosphorus fertilizer+straw returning(NPS), nitrogen and phosphorus fertilizer+organic fertilizer(NPM), nitrogen and phosphorus fertilizer+straw returning+organic fertilizer(NPSM), were set up by using the method of long-term positioning test. The effects of different treatments on soil chemical properties and microbial quantity at different growth stages of cotton in 2021 and the relationship between them were investigated. The results showed that: Returning cotton straw and applying organic fertilizer could reduce soil pH, and NPSM significantly reduced NP by 3. 41%, 1. 86%, 3. 19% and 2. 60% at each growth stage; Returning cotton straw to the field and applying organic fertilizer can improve the nutrient content of soil. Compared with NP, NPSM significantly increased the content of alkali hydrolyzable nitrogen, available potassium, available phosphorus and organic matter by 140. 63%-229. 17%, 35. 86%-60. 54%, 146. 92%-483. 34% and 28. 06%-63. 07% respectively. Compared with the nitrogen fixing bacteria and ammonia fixing fungi in soil, the number of bacteria and ammonia fixing fungi in soil increased by 21. 77% at different stages of straw fertilization; The number of fungi increased by 156. 64%-233. 42%; The number of actinomycetes increased by 107. 40%-158. 66%; The number of nitrogen fixing bacteria increased by 95. 23%-155. 53%; The number of ammonifying bacteria increased by 279. 39%-357. 29%(P<0. 05). Therefore, straw returning combined with organic fertilizer can significantly improve soil properties, increase soil nutrient content and microbial quantity, so as to optimize soil structure and improve soil fertility.Keywords：straw returning;organic fertilizer;continuous cropping cotton field;chemical properties of soil;microorganism18|11|23<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In view of the problem that the flexible disc can not meet the agronomic requirements of horizontal planting in cultivation of sweet potato naked seedlings at present, according to the agronomic requirements, the kinematics analysis was used to investigate the planting process of sweet potato naked seedlings clamped by flexible discs. A mathematical model of sweet potato naked seedlings bending and root movement was constructed. The influencing factors of sweet potato naked seedlings bending orientation were verified by using the method of bench and EDEM software simulation test and the movement track of sweet potato naked seedlings root after touching the ground were studied. The results showed that: 1)The theoretical bending orientation of sweet potato naked seedlings is determined by the height from the rotating center of the disc to the ground, the forward speed of the machine and the rotating speed of the disc. The root of sweet potato naked seedlings moves forward for a certain distance after touching the ground; 2)When the machine speed is 0. 25 m/s, the actual bending orientation of sweet potato naked seedlings is related to the disc speed. When the disc speed is 1. 4 rad/s, the coincidence rate between the actual bending orientation and the theoretical orientation of sweet potato naked seedlings reaches 98%. When the rotational speed of the disc was greater than 1. 2 rad/s, the distance of the root of the sweet potato naked seedlings moving forward is less than 10 mm after touching the ground. In conclusion, under the condition of the machine speed of 0. 25 m/s and the disc speed of 1. 4 rad/s, the sweet potato naked seedlings is planted horizontally, the qualified rate of planting depth is 95. 6%, and the qualified rate of planting posture reaches 87. 8%.Keywords：sweet potato naked seedling;similar horizontal planting;flexible disc;motion posture3|9|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To improve the accuracy of non-destructive estimation of lettuce fresh weight at different growth stages in facility production and to better guide production, based on transfer learning technology and convolution neural network, a new estimating method by using canopy image as input was proposed. The results were compared and analyzed after transfer learning on AlexNet, VGG-16, GoogLeNet, and ResNet-18 models. At the same time, the effects of using different transfer learning methods on the performance of the model were also compared. The training speed and parameters of the model were improved by freezing the convolution layers and reducing the number of full connection layers. The results showed that: 1)AlexNet and VGG-16 models were better to estimate the fresh weight. The determination coefficient R2 of the AlexNet model was 0. 928 0, the standard root mean square error NRMSE was 19. 08%, while the R2 of the VGG-16 transfer learning model was 0. 938 0, and the NRMSE was 17. 71%, respectively. However, the VGG-16 model had the problems that it needed a large number of parameters and was slow to be trained. Therefore, the AlexNet model was selected as the fresh weight estimation model after transfer learning; 2)Compared with the new learning methods, transfer learning based on the pre-trained model could significantly improve the training speed and accuracy; 3)Freezing the convolutional layers could significantly accelerate the training speed of the model and reduce the training time by 18% and reducing the fully connected layers could significantly reduce the number of parameters of the AlexNet model. In summary, the convolution neural network model based on transfer learning can be used for faster estimation of the fresh weight for lettuce, and the method can also be extended and applied to the fresh weight estimation of other leafy vegetables.Keywords：lettuce;fresh weight estimation;convolutional neural network;transfer learning7|9|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To find out the influence of design parameters of hot air duct heating system on the uniformity of root zone temperature distribution, a single substrate cultivation tank was taken as the research objects. The root zone heating system model of hot air duct in solar greenhouse was constructed by using computational fluid dynamics(CFD)method. The root zone temperature distribution law under different inlet temperature, inlet air velocity and the number of air supply duct openings were explored. Orthogonal experiments were designed and numerical simulations were carried out to determine the influence of various factors on the uniformity of root zone temperature distribution. The results show that: The average relative error between the measured and simulated values of root zone temperature is 0. 89% and the root mean square error is 0. 02. The results indicate that the model is reliable. With the increase of air inlet temperature, wind speed and number of openings, the temperature unevenness and maximum temperature in the root zone increase significantly, while the average temperature and minimum temperature do not change significantly. The effect of each parameter on the uniformity of temperature distribution in the root zone in descending order is the number of openings > inlet temperature > inlet wind speed. In conclusion, when the air inlet temperature is 20 ℃, the air inlet speed is 7. 5 m/s and the number of openings is 20, the temperature uniformity in the root zone is the best.Keywords：solar greenhouse;root zone temperature;hot air heating;numerical simulation;inlet temperature7|9|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aim of this study is to explore the active components and antioxidant capacity of different storage times(3, 5, 8, 15, and 20 years)of Danxi Hongqu rice wines. The alcohol content, total acid, pH, total sugar, and non-sugar solidity were determined according to the method of GB/T 13662—2018 “Yellow Rice Wine”. The reducing sugars was measured by 3, 5-dinitrosalicylic acid colorimetric method. The contents of total polyphenols and total flavonoids were determined by Folin-Ciocalteu method. The antioxidant capacities of Hongqu rice wines in vitro were evaluated by 1, 1-diphenyl-2-picrylhydrazyl(DPPH)radical scavenging capacity and oxygen radical absorption capacity(ORAC)tests. The lovastatin content in Hongqu rice wines was measured by HPLC. The results showed as follows: 1)With the increase of storage time, the total sugar content was firstly reduced and then enhanced. The mass concentrations of total sugar and reducing sugar in Hongqu rice wines stored for 20 years were the highest, which were 46. 92 and 22. 35 g/L, respectively. With the growth of storage time, the non-sugar solidity level was firstly increased and then decreased. The mass concentration of non-sugar solidity in Hongqu rice wines stored for 8 years was the highest, which was 33. 95 g/L. 2)The contents of total polyphenols and total flavonoids were firstly elevated slightly and then decreased along with the storage time prolong. The mass concentrations of total polyphenols and total flavonoids in Hongqu rice wines stored for 5 years were the highest, which were 6. 49 and 4. 23 mg/mL, respectively. 3)Different storage times of Hongqu rice wines had strong antioxidant capacity. The Hongqu rice wines stored for 3 years had the strongest DPPH radicals scavenging ability, and the Hongqu rice wines stored for 8 years had the highest ORAC value. 4)The lovastatin level in different storage times of Hongqu rice wines was stable. With the storage time increasing, the total polyphenols content in Hongqu rice wines was increased, the ORAC ability was improved, and the lovastatin level was reduced.Keywords：Hongqu rice wine;polyphenols;antioxidant activity;lovastatin5|8|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Considering the uncertainty of agricultural system and the dynamics of surface water inflow in irrigation area, this study formulates an interval multi-stage double-sided stochastic joint-probabilistic chance-constrained programming model by combining the techniques of interval multi-stage stochastic programming, double-sided stochastic chance-constrained programming and joint-probabilistic programming. This model is applied to Hongyashan irrigation area in Minqin County. The results showed that: 1)The model not only solved the interval uncertainty of the model and random uncertainties in the double-sided constraints, but also reflected the dynamic variations of the system. 2)This study set the individual violation probability that reflected the violation risk of constraint conditions and the joint violation probability that reflects the sum of individual violation probability. Through the given three levels of joint constraint violations and three kinds of individual probability scenarios before solving the developed model, optimal solutions of irrigation schemes, irrigation area and irrigation targets under nine scenarios were obtained. 3)With the increased constraint-violation probability levels, the irrigation benefit of the system gradually increases. When the joint violation probability is raised from 0. 01 to 0. 1, the upper bound value increased by 531 million Yuan and the lower bound value increased by 655 million Yuan. Under different scenarios, the planting area of economic crops such as fruits in the irrigation area was the largest, followed by grain crops, and the planting area of vegetables was the smallest. In conclusion, this research can provide different irrigation schemes for decision makers and a reference for water resources management department to formulate the allocation scheme of main crop irrigation area.Keywords：Hongyashan irrigation area;interval multi-stage stochastic programming;chance-constrained programming;double-sided randomness;dynamic1|9|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aims of this study are to understand the spatial pattern of China Organic Agriculture Certification Center and the type characteristics of the comprehensive influence of the core area(Beijing)under the increasingly complex network structure and production organization of modern organic agriculture, the ArcGIS spatial analysis method, the natural interval grading method, and the comprehensive evaluation method are adopted. Based on the certification data of organic agricultural enterprises, the development and evolution, regional pattern and comprehensive influence of Organic Agricultural Certification Centers in Beijing are investigated. The result shows that: 1)In the past 10 years, the development of Organic Agriculture Certification Centers has shown a trend of steady growth in the initial stage, and its typical characteristics of regional layout are uneven spatial distribution, significant regional polarization, regional agglomeration and gradual regional expansion of the market hinterland. 2)The internal distribution pattern of the three major areas of the Organic Agriculture Certification Centers is divided into 10 types including high-high, medium-medium, and low-low. 3)The number of organic certified products and number of organic production enterprises in the core area of Beijing are unevenly distributed. 4)The impact evaluation of Beijing Organic Agriculture Certification Center can be divided into four categories, Comprehensive, Balanced, Growing and Start-up organic agriculture certification centers, with different functional characteristics and market structures. The spatial layout, spatial connection and organizational effectiveness of the China Organic Agriculture Certification Center, effective organic certification financial subsidy system should be established by the government. The regional Organic Agriculture Certification Centers in the central and western regions should be cultivated. Countermeasures such as developing Balanced and Comprehensive organic agriculture certification center used for reference, building its own brand, exploring foreign markets for comprehensive organic agriculture certification, promoting integration of China's organic certification industry with the international market, accelerating China's organic certified products to expand exports and improve its competitiveness and so on should be taken in future regional development.Keywords：organic agriculture certification center;spatiotemporal evolution;regional pattern;influence of core area;comprehensive evaluation2|8|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Based on a questionnaire survey of 1 994 farmers' in Henan Province, the impact of trust pattern and service outsourcing on farmers' adoption of agricultural green production technology and its transmission mechanism are investigated by using a structural equation model. The results show that: 1)The trust of farmers is composed of special trust and general trust, among which strengthening the trust between farmers and village collectives, township and county governments can significantly improve the level of special trust of farmers, and display the positive promoting characteristics of special trust to the adoption of agricultural green production technology, while the general trust of farmers is not validated; 2)The service outsourcing of farmers has a direct positive effect on the adoption of green production technology, and under the mechanism of service outsourcing, the positive effect of special trust on the adoption of green production technology is strengthened. However, the intermediary effect of service outsourcing is not shown in the general trust of farmers; 3)The results of multigroup analysis of different types of farmers also show that the effect of farmers' special trust on the adoption of green production technology is different due to whether they are engaged in the part-time employment or not. But once they choose service outsourcing, the effect of adopting green production technology by “circuitous” increases significantly, regardless of whether the farmers are engaged in the part-time employment or not, and regardless of their trust relationship and level. Therefore, in order to promote the adoption of agricultural green production technology, we should speed up the construction of community environment with high trust, improve the social trust level of farmers, cultivate the agricultural productive service market, and perfect the extension model of agricultural technology.Keywords：special trust;general trust;service outsourcing;adoption of green production technology in agriculture8|9|7<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to explore the mechanism of the integration of three industries on the performance of farmers' cooperatives, based on the survey data of 254 farmers' cooperatives in Heilongjiang Province, governance mechanism, benefit mechanism, technological progress and policy supply were adopt as mediating variables. A structural equation model with multiple mediating effects was constructed. The results show that: Firstly, the direct effect of the integration of the three industries on improving the performance of cooperatives is significant. Secondly, two intermediary paths, by taking the internal governance mechanism of cooperatives and technological progress as intermediary variables are established. Thirdly, the three-industry integration of farmers' cooperatives promots the improvement of the internal interest mechanism and obtaining government policy supply, but the intermediary effect of interest mechanism and government policy is not significant. Therefore, it is helpful to further improve the performance of farmers' cooperatives by giving full play to the important role of governance mechanisms and technological progress, handling the interests of the three industries in the process of integration properly and avoiding inadequate implementation of policy supply.Keywords：tertiary industry integration;cooperative performance;mediation effect;structural equation model3|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to explore the effective path of fecal pollution control in scale pig breeding, this study empirically analyzes the decision-making factors of manure pollution treatment behavior of farmers of different scales farms from the perspective of small, medium and large-scale comparison based on 1 124 sample data investigated in Jilin and Liaoning. The results show that: Breeding income is still an important factor affecting farmers' manure pollution treatment decisions. Government subsidies play a more significant role in promoting manure pollution treatment of small and large-scale farmers, and strengthening manure pollution treatment publicity and training is more beneficial to medium-scale farmershould be taken as the main development direction, implemented by classification and promoted in a coordinated manner. It is also necessary to promote farmers from internal fecal sewage treatment to independent behavior by carrying out fecal sewage treatment publicity and training, and implementing incentive measures such as supervision and subsidies.Keywords：scale pig breeding;manure pollution treatment;behavioral decision;heterogeneity;green development1|9|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aim of this study is to explore the economic and environmental effects of the policy of prohibiting livestock and poultry production. Based on the data of 31 provinces in China(the data do not include those of Hong Kong, Macao and Taiwan regions), this study analyzes the impact of the policy implementation on livestock and poultry breeding quantity, breed structure, scale structure and spatial layout, and calculates the production of livestock and poultry manure, nitrogen and phosphorus pollution and the load of cultivated land using the excretion coefficient method. The equal standard pollution loading method is used to evaluate the water pollution. The results indicate that: 1)The total livestock and poultry production decrease rapidly, the individual investors withdraw gradually, and the industrial production capacity is concentrated in large households. The breeding of pig and cattle is greatly impacted by the policy, and the livestock and poultry farming has a tendency to shift to some areas. 2)The direct reduction of the breeding quantity caused by the implementation of the policy helps to slightly alleviate the cultivated land pollution and water pollution pressure caused by livestock production, but there are still large risks of environmental pollution and pollution transfer. In most areas of China, the manure load of livestock and poultry exceeds the carrying capacity of local arable land, and the areas with a large amount of manure show a trend of agglomeration, and the N and P pollution in some areas still exceed the standard. A few areas are still at high risk of water pollution. Therefore, it is necessary for the government to further strengthen the planning and layout of overall and local breeding areas, improve the resource treatment capacity of livestock and poultry manure in breeding farms, actively popularize the integrated agricultural production mode of planting and breeding, promote the conversion of manure and organic manure from livestock and poultry and improve the pollution emission standards of livestock and poultry breeding.Keywords：policy of prohibiting livestock and poultry production;livestock manure;load of cultivated land;equal standard pollution loading10|8|6<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aim of this study was to explore the path for high quality regional coordinated development of agricultural economy in China. Based on the provincial panel data from 2000 to 2019, Dagum Gini coefficient, Kernel density estimation, δ convergence and β convergence methods were used to empirically investigate the regional disparity, spatial disequilibrium and convergence of high quality development of agricultural economy in three regions and all over China. The results show that: 1)The overall disparity of high quality development of agricultural economy in China and the disparity between regions are diminishing, but the regional disparity is still prominent, and the inter-regional disparity is the main source of the overall disparity. 2)At the national or regional level, the spatial disequilibrium of high quality development of agricultural economy is diminishing gradually. However, there are still significant spatial disequilibrium distribution and regional polarization, indicating obvious spatial distribution pattern of the east, the middle and the west ladder decline. 3)There are significant δ convergence characteristics, absolute β convergence and conditional β convergence trend in the high quality development of agricultural economy in China, and the three regions have obvious catch-up effect. Among them, the convergence rate is the fastest in the western region, followed by the central region and the slowest in the eastern region. Finally, three policy enlightenments are put forward to optimize the spatial disequilibrium pattern of high quality development of agricultural economy by following the comparative advantage, promoting regional coordinated development and facilitating transition and upgrading.Keywords：high quality development of agricultural economy;spatial disequilibrium;Kernel density estimation;δ;β;convergence3|9|10<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：As the modern world is undergoing tremendous changes unseen in a century, the internal and external conditions of China's development are changing profoundly. The agricultural higher education system needs to make timely and responsive changes. Based on the current situation and problems of the agricultural higher education system, this study focuses on the theme of the development path of the agricultural higher education system in the new era. Profound analysis on the opportunities and challenges faced is preformed to put forward the conceptual framework of agricultural higher education system in the new era. This framework explains the ideas of constructing the agricultural higher education system in the new era from five perspectives of reaching a consensus concept, focusing on the two cores, following the three logical lines, sticking to the four targets, and constructing a new system of “five in one”, which will provide ideas and references for the transformation and development of world-class agricultural universities.Keywords：new era;agricultural higher education system;conceptual framwork;university transformation;development path2|9|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
