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

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

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

【Objective】China is a significant wheat producer and consumer in the world. It is very important for our food security to making sure the stable wheat production. Wheat powdery mildew is an important leaf disease to affect the global wheat yield. Breeding resistant wheat varieties is one of the most economically and environmentally effective way to manage this disease. Identification of new adult plant resistant loci is very important for breeders to develop durable powdery mildew-resistant wheat varieties. 【Method】The CIMMYT-derived common wheat (Triticum aestivum L.) Arableu#1, showed susceptibility to powdery mildew at the seedling stage, but exhibited a high level of resistance to this disease at the adult plant stage in the field. In order to understand the genetic basis of powdery mildew resistance in this line, we made an F₅ recombinant inbred line (RIL) population between Arableu#1 and the susceptible line Apav#1 and genotyped by genotyping-by-sequencing (GBS) platform. We obtained 4 298 polymorphic molecular markers between the parents and analyze the 142 RILs. Joinmap 4.1 and IciMapping 4.1 were respectively used to construct the linage maps and identify the powdery mildew resistance QTL in this study. 【Result】Four adult plant resistance loci from Arableu#1 were identified on wheat chromosome arms 1BL, 5BL, 6BS and 7BL, while two loci from Apav#1 on chromosomes 2DS and 4BL, which can explain the powdery mildew disease severity variation from 3.1% to 28.5%. The MFDS of RIL reached the lowest level when it carried all six detected resistance loci, while RILs combing QPm.hzau-1BL, QPm.hzau-4BL, QPm.hzau-5BL, and QPm.hzau-7BL also showed lower disease severity over multiple environments. 【Conclusion】KASP markers KASP-5B-1 and KASP-7B-2 for QPm.hzau-5BL and QPm.hzau-7BL, respectively, were developed in the present study. The two loci showed varying degrees of resistance to powdery mildew when present individually or in combination based on the genotype and phenotype of 570 wheat germplasm collections. Additionally, the frequency of these two loci in Chinese wheat materials is lower compared to CIMMYT's wheat germplasm. A line combining 6 QTLs was found and it showed near-immune resistance to powdery mildew in the field. This material will be an important germplasm resource for breeders to develop powdery mildew-resistant wheat varieties.

【Objective】The aim of this study was to analyze the effects of different planting densities and row spacing configurations on stem carbohydrate accumulation and lodging resistance of wheat under ridge-furrow rainfall harvesting planting mode, and to clarify the reasonable density and row spacing of wheat under ridge-furrow rainfall harvesting planting mode, so as to provide a theoretical basis for further stabilizing and increasing wheat yield. 【Method】Xinong 979 was the main wheat cultivar in the arid area of north China, which was used as the experimental material. In 2019-2021, two planting densities (low density: 1.8 million plants per hm²; high density: 2.25 million plants per hm²) and two row spacing (equal row spacing: 20 cm; non-equal spacing: 12.5 cm:35 cm:12.5 cm) treatments were set in the rainfall harvesting planting mode. The effects of different densities and row spacing on photosynthetic rate of middle and lower leaves in wheat plants, content of stem non-structural carbohydrates and structural carbohydrates, stem breaking moment and lodging index, and grain yield were analyzed. 【Result】The net photosynthetic rate (Pn) of the middle and lower leaves (the third leaf, the fourth leaf and the fifth leaf) in wheat plants, the content of non-structural carbohydrates (glucose, fructose, sucrose) and structural carbohydrates (hemicellulose, cellulose) in the second internode at the base of stem, and the stem breaking moment were significantly decreased with the increase of planting density in the rainfall harvesting planting mode, but the stem lodging index increased significantly. However, under high-density planting condition, non-equal row spacing treatment could significantly change all plant indexes. Compared with high planting density + equal spacing treatment, the Pn of the third leaf, the fourth leaf and the fifth leaf in plants increased significantly, with increases of 7.7%-16.5%, 5.3%-37.7% and 11.9%-24.9%, respectively; the content of glucose, fructose and sucrose in stems increased by 9.8%-15.0%, 8.8%-27.4% and 8.2%-41.1%, respectively; the content of hemicellulose and cellulose increased by 4.5%-19.8%, 5.9%-31.2%, respectively; the stem breaking moment increased by 4.8%-17.3%, the stem lodging index decreased by 10.9%-25.9%, while wheat yield was significantly increased by 13.5%-15.2%. Correlation analysis showed that, the content of glucose, fructose and sucrose in the basal internode of wheat stem were positively correlated with the content of hemicellulose and cellulose. Non-structural carbohydrates and structural carbohydrates in wheat stem were positively correlated with Pn of middle and lower leaves as well as stem breaking moment, however, they were negatively correlated with lodging index. 【Conclusion】Under the rainfall harvesting planting mode, adjusting population spatial distribution by non-equal row spacing could effectively increase photosynthetic rate of middle and lower leaves of wheat plants, promote the synthesis and accumulation of sugar substances in stems, and enhance the lodging resistance of wheat stem, furthermore, reduce the lodging incidence of wheat and improve grain yield.

【Objective】The leaf area index (LAI) is a vital indicator for evaluating crop growth, photosynthesis, and transpiration. The objective of this study is to explore the cotton LAI estimation models based on multi-spectral data from drones at different growth stages and multiple growth stages, clarify the variation patterns of cotton LAI estimation models during different growth stages, and to provide a basis for real-time understanding of cotton growth and scientific field management tailored to local conditions. 【Method】The DJI Elf 4 multi-spectral UAV was used to acquire multi-spectral images and RGB images of cotton at budding stage, initial flowering stage, boll setting and open-boll stages. Five multi-spectral indices, namely normalized difference vegetation index (NDVI), normalized green difference vegetation index (GNDVI), normalized difference red-edge index (NDRE), leaf chlorophyll index (LCI), optimized soil adjusted vegetation index (OSAVI), and five color indices, namely modified green-red vegetation index (MGRVI), green-red vegetation index (GRVI), green leaf algorithm (GLA), excess red index (EXR), and visible atmospherically resistant vegetation index (VARI), were selected to build a data set for each growth stage of cotton and multiple growth stages of cotton growth, respectively. Combined with the punching method to obtain actual ground LAI data, the machine learning algorithms of partial least squares regression (PLSR), ridge regression (RR), random forest (RF), support vector machine (SVM) and back propagation (BP) were used to construct a cotton LAI prediction model. 【Result】The LAI of cotton exhibited an increasing and then decreasing pattern during the growth stage. Notably, the mean LAI values of cotton at the inner side of the budding stage, initial flowering stage, and boll setting stage were significantly greater than those at the lateral side (P<0.05). The selected indices exhibited significant correlations with each other across the periods (P<0.05). In general, the correlation between multi-spectral index and color index showed a decreasing trend as the growth stage progressed, and the selected indices were significantly correlated with cotton LAI in all stages (P<0.05), the correlation coefficients of multi-spectral index ranged from 0.35 to 0.85, and the correlation coefficients of color index ranged from 0.49 to 0.71, and those with a larger absolute value of the correlation coefficients were mostly multi-spectral indices, while those of the correlation coefficients of color index and cotton LAI were smaller. The estimated model performance results showed that the multi-spectral index was better than the color index in the cotton growth models, the predictive performance of the index models showed certain regularity with the change of growth, and NDVI was the optimal index for predicting cotton LAI. From the model results, the RF model and BP model obtained higher estimation accuracy under each growth stage. The LAI inversion model at the initial flowering stage had the highest accuracy, with the optimal model validation set R² of 0.809, MAE of 0.288, and NRMSE of 0.120. The optimal model validation set for the multiple growth stages had the R² of 0.386, MAE of 0.700, and NRMSE of 0.198. 【Conclusion】There are significant differences in LAI between the inner and lateral sides of cotton during the budding stage, initial flowering stage, and boll setting stage. NDVI emerged as the optimal index for predicting cotton LAI at all growth stages, with the RF and BP models demonstrating superior performance. The effectiveness of the multiple growth stages model was notably lower compared to that of the single-growth model, with the optimal index identified as GNDVI and the optimal model as BP. The initial flowering stage appeared to be the optimal window for predicting cotton LAI. These findings can provide theoretical basis and technical support for utilizing UAV remote sensing to monitor cotton LAI.

Bt toxin is a macromolecular protein derived from Bacillus thuringiensis with special insecticidal function. Its preparation and transgenic crops have been widely used in pest control, and have produced huge economic and social ecological benefits. Exploiting and improving the application value of Bt toxin is a hot spot of continuous research. In particular, as the structure and function of Bt toxin and its mechanism of action appear clearer, it has created conditions for its functional modification and innovative application. As a result, the related research has flourished and achieved remarkable results. A large number of studies have shown that strategies such as site directed mutagenesis, domain replacement or fusion, and anti-idiotype antibody simulation are effective means to rationally design novel insecticidal proteins with higher activity, greater stability, wider insecticidal spectrum and higher non-target biosecurity. Those novel insecticidal proteins are different from parent Bt toxins, of which are mutants, structural heterozygotes and even functional effector antibodies. In addition, it is also an important approach to promote the application value of Bt toxin by use of innovative synergistic strategies such as catalytic toxin activation, driving toxin-targeted receptor binding, promoting toxin expression and the synergistic effect of combination or co-expression of homologous or heterologous insecticidal materials. This paper summarizes the structure and function of Bt toxin and its mechanism of action. It also reviews the research progress in rational design of novel insecticidal proteins such as mutants, structural heterozygotes and functional effector antibodies based on Bt toxin function modification, and innovative application strategies based on Bt toxin function enhancement. The future development trend and potential shortcut of rational design and innovative application strategy for insecticidal protein based on Bt toxin were discussed. Furthermore, the author’s team combined it with the latest achievements in targeting design and development of the insecticidal function effector antibodies simulating Bt toxin. This paper is expected to provide more comprehensive and valuable literature information and enlighten ideas for the related research based on Bt toxin.

【Objective】The passivation effect of passivator and compound microbial fertilizer on cadmium (Cd) activity in slightly Cd-polluted weak alkaline farmland soil in northern Henan Province was studied, and their effects on Cd accumulation and translocation in different organs and yield of winter wheat were investigated too. The purpose of this study was to explore soil remediation materials for efficient remediation of Cd-contaminated soil, to reduce Cd content in winter wheat grains, and to screen wheat varieties with low Cd accumulation, so as to provide the technical support for the safe and efficient production of wheat in lightly polluted weak alkaline farmland in northern Henan Province. 【Method】In two consecutive winter wheat growing seasons of 2020-2022, two-factor split field comparison experiments of four different soil remediation materials (CK, no soil remediation treatment; CMF, single application of compound microbial fertilizer; GP, single application of soil passivator; CMF+GP, combination of compound microbial fertilizer and soil passivator) and six winter wheat varieties (Xinhuamai818, Luomai 163, Zhengmai 9023, Xinmai 296, Zhengmai 136, and Zhengmai 7698) in northern Henan Province were set up and used in the weakly Cd-polluted alkaline farmland. The changes of available Cd in soil, Cd contents in aboveground organs of wheat plants, enrichment coefficient (BCF), transport coefficient (TF), their correlations, and winter wheat yields and its components were analyzed. 【Result】(1) In two winter wheat growing seasons (2020-2021 and 2021-2022), compared with CK, single application and equal combination application of passivation agent and compound microbial fertilizer could remarkably reduce the content of available Cd in soil. CMF+GP treatment had the best effect, which significantly and effectively reduced the available Cd content by 17.6%-22.4% in the surface soil of the roots among the six varieties. The decreased available Cd in soil was related to the changes of Cd content in the aboveground organs of winter wheat plants, and there were also some differences between the same organs of different varieties. (2) Single application of soil passivator and compound microbial fertilizer, as well as equal combined application of soil passivator and compound microbial fertilizer, could make Xinhuamai 818, Luomai 163 and Zhengmai 9023 decrease TF_{Stem sheath-leaf}, TF_{Stem sheath-grain}, increase TF_{Stem sheath-(Spike shaft+chaff)}, TF_{Leaf-(Spike shaft+chaff)}, reduce BCF_{Stem sheath} and BCF_Leaf, and make wheat body in order to reduce BCF _Grain, the content of Cd in it shifted to panicle axis + glume. In contrast, they did not reduce TF_{Stem sheath-Leaf} and BCF _{Stem sheath} of Xinmai 296, whereas increased BCF _{Stem sheath} of Zhengmai 136 and Zhengmai 7698. (3) Application of passivating agents and compound microbial fertilizers in soil could comprehensively regulate the number of ears, grains per ear and 1000-kernel weight of winter wheat plants, and improve the grain yields of winter wheat. However, variance analysis on soil remediation treatment and varieties showed that the increased grain yields in their interactions was mainly due to the increased ear numbers. Under CMF+GP treatment, the grain yield of Zhengmai 136 variety was the highest among all treatments, which was 7 317.17 kg·hm^-2 and 10 485.32 kg·hm^-2 in two consecutive 2020-2021 and 2021-2022 winter wheat growing seasons, respectively. 【Conclusion】The application of compound microbial fertilizer and soil passivator could effectively reduce the available Cd content in the rhizosphere soil with weak alkaline and mild Cd pollution in northern Henan Province, and regulate the enrichment coefficient and transport coefficient of soil Cd in various organs of winter wheat plants. The combination treatment of compound microbial fertilizer and soil passivator with the same applied amounts was better than single treatment, which could also reduce the Cd content of winter wheat grains to the maximum extent, and significantly improve the yield of winter wheat varieties. In addition, the combination of planting modes combined with the low Cd accumulation and high yield variety Zhengmai 136 screened out, could achieve the high grain yields and safe production of winter wheat in the farmland with weak alkaline Cd pollution in northern Henan Province.

Organosiloxane-based adjuvant (or organosilicon adjuvant), one of the silicone-fluide products, is polysiloxane, predominantly composed of covalently bonded silicon and oxygen atoms. Organosiloxane-based adjuvants are widely used as additives for daily chemicals and textile products, but also as agrochemical adjuvants in agriculture due to their super spreading and penetrating abilities. At present, China’s production and sales of silicone products have reached above 2 million tons, accounting for more than 50% of the world’s total amount. China has become the world’s largest producer, consumer and net exporter of raw materials of silicone, and the production capacity of polysiloxane has reached more than 60% of the world’s total. As organosiloxane residues detected in environment (especially in water, sludge/soil and other environmental samples, aquatic food chain, as well as human tissues), their impacts on agricultural ecological environment are increasingly exposed due to the widely application of organosiloxane-based adjuvants, while the environmental risks from silicone-based agrochemical adjuvants, including ecotoxicity and environmental safety risks, have also attracted great concern. In recent years, volatile cyclomethylcyclosiloxanes (such as D4 (octamethylcyclotetrasiloxane), D5 (decamethylcyclopentasiloxane) and D6 (dodecylcyclohexasiloxane)) have been recognized as emerging organic pollutants, or listed as priority controlled chemicals by EU and other countries, because of their environmental persistence, bioaccumulation and potential toxicity. Based on the relevant scientific research literatures published since 1991 on the environmental residues of organosiloxane-based adjuvants and the ecological environmental safety risks in the use of organosiloxane-based adjuvant (including organosiloxane-based agrochemical adjuvants), this paper reviewed and analyzed the environmental residues of organosiloxane-based adjuvants, and their impacts directly or indirectly on agricultural ecological environmental safety. This review mainly focused on the following two aspects: (1) the organosiloxane residues in environment and their impacts on the agricultural ecological environment safety, including organosiloxane residues and fates in the process of wastewater treatment, aquatic food chain pollution risks from organosiloxane residues in water, soil ecological pollution risks from organosiloxane residues in sludge, and human health risks from organosiloxane residues in food; (2) the current situation and environmental safety risks for the use of organosiloxane-based agrochemical adjuvants, including organosiloxane residues and ecotoxicity risks from siloxane-based agrochemical adjuvants, and the management for the use of organosiloxane-based agrochemical adjuvants. This paper also discussed the management status and problems associated with siloxane-based products. For organosiloxane as agrochemical adjuvants, organosiloxane-based adjuvants were largely assumed to be “biologically inert”, and usually no risk assessment (such as ecotoxicity test and environmental monitoring) was required. Also, the adjuvant inert ingredients were generally protected as “trade-secrets” or confidential business information, and the inert ingredients were rarely identified on product labels. At present, there are no regulatory requirements for the use of organosilicone-based adjuvants in fertilizer products as agrochemical adjuvants (such as foliar fertilizer additives) in China, posing potential environmental safety risks. This paper discussed that over-addition with organosiloxane-based agrochemical adjuvants might increase their residues in soil-crop-water systems, and their ecotoxicity risks, as well as potential threats to food safety and human health. It is suggested that relevant management and research units need to pay more attention to environmental monitoring for organosiloxane residues and fates in the application process of organosiloxane-based adjuvants, and especially strengthen the research on the impacts of organosiloxane residues from organosiloxane-based agrochemical adjuvants on water, soil, animal and plant growth, as well as human health.

【Objective】Arbuscular mycorrhizal (AM) fungi play a significant role in enhancing plant growth and improving resistance to environmental stress. The aim of this study was to screen AM fungi that can withstand drought stress in pear seedlings, so as to establish a theoretical foundation and technical approach for pear mycorrhizal cultivation. 【Method】In this study, a pot experiment and high-throughput sequencing technology were employed to investigate the effects of single and mixed inoculation with indigenous AM fungi, including Claroideoglomus lamellosum (Cl), the exogenous fungus Funneliformis mosseae (Fm), Rhizophagus intraradices (Ri), and Acaulospora mellea (Am), on the growth of Pyrus betulaefolia seedlings under normal and drought conditions. The changes in the AM fungal community in the roots and rhizosphere soil of P. betulaefolia seedlings were analyzed under mixed inoculation (Mix) after 0, 3, and 6 weeks of drought treatment. 【Result】 Under normal and drought conditions, the single inoculation with Cl, Ri, and Mix significantly increased the plant height, stem diameter, leaf area, and relative water content of the leaves of pear seedlings, resulting in a dry weight increase of 35.26% to 52.20%. Additionally, the uptake of phosphorus, potassium, calcium, and magnesium in the aboveground part of the seedlings was enhanced, especially phosphorus uptake, with a mycorrhizal phosphorus uptake effect of up to 1.0. The exogenous fungus Am showed less effectiveness, while Fm inhibited the growth of P. betulaefolia seedlings under normal water supply conditions. Regression analysis indicated that the growth and element absorption effects of mycorrhizal fungi increased with the degree of infection. Under drought stress, AM fungal inoculation significantly reduced the MDA (malondialdehyde) content in the leaves of P. betulaefolia seedlings and increased the activity of antioxidant enzymes and the content of proline to varying degrees. Sequencing results demonstrated that the structure of the AM fungal community in the roots and rhizosphere soil of P. betulaefolia seedlings changed significantly under drought stress compared with normal water conditions. The exogenous fungus Ri dominated the community, followed by Cl and Am, while Fm was the least abundant. The abundance of Ri in the roots significantly increased with the degree of drought stress. 【Conclusion】In conclusion, the different AM fungi had varying effects on the growth of P. betulaefolia seedlings, with the indigenous strain Cl and the exogenous strain Ri showing strong growth-promoting effect and drought resistance. The increase in Ri abundance in the AM fungal community was an important adaptation mechanism for P. betulaefolia seedlings to withstand drought stress.

【Objective】The aim of this study was to establish a comprehensive evaluation system for early flowering garden chrysanthemums, and to select plant lines with flowering periods from mid-September to mid-October, of which flower colors were close to pure red or yellow with novel flower type, round plant shape and excellent comprehensive performance to enrich ornamentals for early autumn festivals in Northen China, so as to provide breeding materials and selection methods for further breeding of early flowering garden chrysanthemum. 【Method】Using 3 early-flowering parents and 1 high double-flowering parent with bright color of small flowered chrysanthemum and 25 asexual hybrid progenies as test materials, 30 original traits were observed from 5 aspects, including flower color, flowering period, flower type, plant type, and leaf type. The selected 18 key traits were used as evaluation factors, and then a comprehensive evaluation system was established using Analytic Hierarchy Process and K-Means clustering analysis to conduct the comprehensive screening of hybrid lines. 【Result】The weight values of each trait of analytic hierarchy process were determined with the breeding objectives of early flowering, round flower type, and stable red and yellow flower color. Among them, the weight value of the initial flowering time (0.1817) was the largest, followed by the flower color stability (0.1695), the number of flowers per plant in the full flowering period (0.1383), the flowering duration (0.1301), the flower color suitability (0.0565), the flower uniformity in the full flowering period (0.0565 ), the inflorescence diameter (0.0539), and the number of ligulate flowers (0.0574). The 29 materials were divided into 3 grades by K-Means clustering analysis: 10 in grade I, 11 in grade II, and 8 in grade III, accounting for 34.38%, 37.93% and 27.59%, respectively. The traits of the hybrid progeny were widely separated, and the flower color, flower type, and plant type all showed transgressive traits, but the flowering period was still the earliest in the two early flowering parents, which was in line with the previous studies that the flowering period was a quantitative trait controlled by multiple genes. Therefore, the early flowering breeding still needs to screen parents and increase the resources of open-field small chrysanthemums that can be used in early autumn. 【Conclusion】 This evaluation method integrated the advantages of various evaluation systems, characterized the traits observed in the field with quantitative results, and conducted hierarchical analysis and evaluation guided by breeding objectives, which provided a quantitative method for comprehensive evaluation and screening of excellent varieties of early flowering garden chrysanthemum. The data analysis results indicated that the evaluation system established in this study could effectively evaluate and screen early flowering garden chrysanthemums, providing a reliable method for the breeding of new varieties of early flowering garden chrysanthemums, and helping to improve the efficiency of selecting excellent germplasm for future breeding project. Finally, 10 early flowering garden chrysanthemum strains with excellent ornamental traits were selected, which could be used as new varieties or strains and also as further breeding materials.

【Objective】The aim of this study was to investigate the effects of mannitol on production characteristics and reactive oxygen species (ROS) scavenging ability of Volvariella volvacea subcultured strains, and to explore a simple and effective method for the rejuvenation of V. volvacea degenerated strains. 【Method】The tissue isolation subcultured strains T6, T12 and T19 were obtained by previous study of our research group, and T6 was obtained after 6 successive subculture, while T12 and T19 was obtained after 12 and 19 successive subculture, respectively. The original strain (T0), referred to as V844, was a strain used in commercial agricultural cultivation. The glucose in the traditional potato dextrose agar (PDA) was replaced by mannitol of the same mass, then physiological traits were determined in mycelia. The agronomic characters of fruiting body were measured by adding mannitol to the culture medium. ROS accumulation was reflected using nitrotetrazolium blue chloride (NBT) staining of V. volvacea mycelia, superoxide anion ($\mathrm{O}_{2}^{\bar{.}}$) and hydrogen peroxide (H₂O₂) content. The expression levels of antioxidant enzyme genes were detected by real-time quantitative PCR (RT-qPCR). The activity of antioxidant enzymes was measured by the kit. The number of nuclei and mitochondrial membrane potential were determined by mycelium staining. The energy indexes were determined by high performance liquid chromatography (HPLC). 【Result】Mannitol treatment had no significant effect on non-degraded strains T0 and T6, but could effectively restore the production characteristics and ROS scavenging ability of degraded strains T12 and T19. After mannitol treatment, the mycelial growth rate of T12 and T19 was increased by 31.46% and 20.99%, respectively, and the mycelial biomass was increased by 97.33% and 76.36%, respectively. The mannitol treatment shortened the production cycle of T12 by 12.24% and increased the biological efficiency by 17.97%, thus restoring it to T0 level. In addition, the mannitol treatment caused T19 to regrow its fruiting body, which had been severely degraded and lost its ability to produce fruiting bodies. Meanwhile, mannitol treatment increased the relative expression of Cu/Zn superoxide dismutase (Cu/Zn-sod) gene in T12 and T19 by 24.64% and 61.54%, respectively, and the relative expression of Mn-sod2 gene by 19.76% and 267.09%, respectively. Similarly, the relative expression of glutathione peroxidase (gpx) gene was up-regulated by 25.67% and 55.82%, respectively. More importantly, the activity of SOD in T12 and T19 increased by 10.79% and 72.32%, and the activity of GPX increased by 16.98% and 103.85%, respectively. The accumulation of ROS in T12 and T19 was significantly reduced by mannitol treatment, in which the $\mathrm{O}_{2}^{\bar{.}}$ content in T12 and T19 decreased by 35.96% and 41.62%, while the H₂O₂ content decreased by 14.44% and 18.26%, respectively. Furthermore, the mannitol treatment significantly increased the number of nuclei and mitochondrial membrane potential in T12 and T19. Mannitol treatment could increase ATP content in T12 and T19 by 17.08% and 14.55%, and EC value by 4.52% and 0.92%, respectively. 【Conclusion】Mannitol treatment could significantly improve the antioxidant capacity and mitochondrial function of the degenerated strains T12 and T19, and effectively restore their production traits.

【Objective】 The study aimed to identify important candidate genes and signaling pathways associated with dry feather traits by comparing the morphological and gene expression differences between the feather follicles of dry and undried feathers. 【Method】 Three samples of skin tissue were selected from each of the undried and dried feathers. The histological examinations were used to compare the morphological differences between the feather follicles of dried and undried feathers. RNA-seq technology was employed to compare the differentially expressed genes (DEGs) between the two groups of skin samples. The accuracy of transcriptome results was validated by using the fluorescent quantitative PCR technique (RT-qPCR). 【Result】 By histological H.E staining, it was confirmed that the feather follicles of the undried feathers were in the growth phase, while the feather follicles of the dried feathers were in the resting phase. The feather follicle skin samples at the growth stage were used as controls, 942 DEGs were identified in resting feather follicle samples (|fold-change|>2 and P<0.05), including 384 significantly down-regulated DEGs and 558 upregulated DEGs. Gene ontology (Go) analysis suggested that the DEGs were significantly enriched in cell division, cycle regulation, and other related biological processes. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway results showed that the DEGs were related to MAPK, TGF-β, p53, and cell cycle-related signaling pathways. Protein-protein interaction (PPI) network was constructed and six hub genes were obtained by CytoHubba analysis, including CDK1, MAD2L1, BUB1, CCNB2, PLK1, and BUB1B. Gene Set Enrichment Analysis (GSEA) results indicated that the signaling pathways related to the tight junction, insulin, MAPK, TGF-β, and cell cycle-related pathways were significantly associated with the growth cycle of chicken feather follicles. The expression patterns of 8 DEGs detected by RT-qPCR were consistent with the RNA-seq results. 【Conclusion】 In summary, the dry feather traits of chickens were related to the development of feather follicle cycles. Signaling pathways such as MAPK and TGF-β might play important roles in feather growth and development by regulating the expression of cell cycle-related genes. The study provided clues for understanding the molecular regulatory mechanisms for dry feather traits in yellow-feathered broiler chickens.

【Background】Mycoplasma hyopneumoniae (Mhp) invades the body through respiratory mucosa, then it destroys the inflammatory balance and causes inflammatory damage. Short palate lung and nasal epithelial clone1 (SPLUNC1) is a protein secreted by respiratory mucosa with important antibacterial and anti-inflammatory functions, it is considered to be a “signal sensor” for respiratory mucosa in the face of danger signals. 【Objective】This study focused on the interaction between Mhp and SPLUNC1, and analyzed the influence of Mhp on the expression of SPLUNC1 and the regulatory effect of SPLUNC1 on the inflammatory response caused by Mhp. This study also revealed a new mechanism of inflammatory damage caused by Mhp, and it was of great significance to resolve the problem of persistent infection of Mhp. 【Method】Quantitative PCR, indirect immunofluorescence and Western-blotting methods were used to detect the effects of Mhp on SPLUNC1 transcription and expression in PBECs and piglets. Porcine SPLUNC1 gene was cloned and amplified from the PBECs, and the eukaryotic and prokaryotic expression recombinant plasmids pCDNA3.1- SPLUNC1 and pET28a-SPLUNC1 were constructed successfully. Meanwhile, siRNA interference sequence targeting SPLUNC1 were also designed. The effect of SPLUNC1 on the growth of Mhp was clarified by in vitro incubation experiment and SPLUNC1 blocking experiment in mice. After over-expressing or siRNA interfering of SPLUNC1, Western-blotting, IFA and ELISA were used to detect the effects of SPLUNC1 on the Mhp adhesion, CXCL8 expression and the activation of MAPK pathway. 【Result】Mhp infection induced inflammatory damage, accompanied by CXCL8, TNFα and IL-1β expression in the lung. Meanwhile, the transcription and protein expression of SPLUNC1 was also inhibited in vivo and PBECs after Mhp infection. The above studies indicated that Mhp induced pulmonary inflammatory response and inhibited the expression of SPLUNC1. Over-expression of SPLUNC1 in PBECs significantly decreased CXCL8 expression, on the contrary, the knockdown of SPLUNC1 by siRNA interference significantly increased CXCL8 expression. The result showed that SPLUNC1 negatively regulated CXCL8 expression caused by Mhp infection. The growth of Mhp in vivo and vitro was not significantly inhibited by SPLUNC1. Over-expression or siRNA interference of SPLUNC1 also had no significant effect on the adhesion of Mhp. The over-expression of SPLUNC1 inhibited the activation of pERK and IκBα, whereas siRNA interference of SPLUNC1 upregulated the activation of pERK and IκBα. SPLUNC1 inhibited CXCL8 expression by inhibiting the activation of MAPK-ERK pathway. 【Conclusion】The respiratory mucosa regulated the expression of CXCL8 through SPLUNC1 to maintain the inflammatory balance of the host. However, in the process of infection, Mhp destroyed the inflammatory balance by inhibiting SPLUNC1 expression, thus causing inflammatory damage. Finally, this study provided an important basis for understanding the mechanism of infection and injury of Mhp.

【Objective】 Analyzing the evolutionary patterns of genetic diversity of wheat germplasm resources, providing richer and more diverse original parental materials for parental selection and variety selection in wheat breeding in Shanxi Province.【Method】 Using 323 landraces and 105 cultivated varieties as natural populations, a 55K SNP chip was used to perform whole genome scanning on 428 natural populations, analyzing genetic diversity, genetic structure, principal components, genetic clustering, and phylogenetic relationships among varieties. 【Result】 The distribution of SNP loci on 21 chromosomes ranged from 329 to 1 639, with an average of 1 152. The distribution range of 7 partially homologous groups is 2 154-3 852, with an average of approximately 3 456. The distribution pattern of the genome is: B genome>A genome>D genome. Genomic annotation polymorphism markers have the highest distribution among gene regions, accounting for about 50%. Analysis shows that SNP loci cover 21 chromosomes, 7 homologous groups and 3 genomes, but their distribution varies, with a polymorphism rate of 45.60%. The average observed heterozygosity of the entire population (0.0185) was lower than the expected heterozygosity (0.4992). The changes in the average shannon wiener index and polymorphism information content of the entire natural population were not significant. Comparing the diversity parameters of natural populations, it was found that the genetic diversity of the population is not high, the genetic diversity of cultivated varieties is slightly higher than that landraces. The population structure analysis of natural populations divides the population into two major groups. Group I has 307 materials, mainly landraces. Group Ⅱ has 121 materials, mainly cultivated varieties. The natural groups were divided into five groups by both principal component and cluster analysis. The average genetic distance between the varieties in group I is 0.21831, with a range of 0.00127-0.72461. The average genetic distance between varieties in group Ⅱ is 0.14619, with a range of 0.00038-0.76489. The varieties in group Ⅲ the average genetic distance between the varieties of group Ⅳ is 0.16521, with a range of 0.00049-0.43033. The average genetic distance between varieties of group Ⅳ is 0.17643, with a range of 0.00118-0.60496. The average genetic distance between varieties of group V is 0.12039, with a range of 0.00042-0.37032. It can be seen that the variation of genetic distance between wheat varieties is large in Shanxi Province. However, the average genetic distance value is low, the clustering classification differentiation is obvious. The genetic relationship between varieties in the middle of the group is relatively close. Comparison shows that the average genetic distance of group I and group Ⅳ is higher than that of group Ⅱ, group Ⅲ and group V. The genetic distance variation of group I and group Ⅳ is higher than that of group Ⅲ and group V. It can be seen that the genetic distance of cultivated varieties is generally greater than that of landraces.【Conclusion】 The 55K SNP chip was used to analyze the genetic diversity of Shanxi winter wheat germplasm resources, clarifying the distribution characteristics of genetic diversity at the genomic level between Shanxi wheat cultivated varieties and landraces. The introduction of exogenous genes into cultivated varieties is beneficial for improving genetic diversity, while the genetic diversity of landraces is relatively low. At the same time, the genetic relationships of very few varieties are polarized, so it should be rationally used differently in subsequent utilization.

【Objective】 In order to provide theoretical basis for molecular breeding of soybean drought resistance, the different evaluation indexes of drought resistance were comprehensively used to screen soybean germplasm with drought-resistance, and the candidate drought-tolerant genes were identified. 【Method】 In 2018, 2019, 2020 and 2021, a total of 188 soybean germplasm were used to determine pod number per plant, biomass per plant and yield per plant under well-watered and drought stressed conditions. Drought resistance index (DI), improved drought resistance index (IDI), weighted drought resistance coefficient (WDC) and weighted drought resistance index (WDI) were used to identify drought resistance of soybean germplasm. The single nucleotide polymorphisms (SNP) loci significantly associated with these parameters were detected by genome-wide association study (GWAS), and the candidate genes for drought resistance were screened by RNA-seq and qRT-PCR analysis of soybean seedling leaves under drought stress. 【Result】 The DI, IDI, WDC and WDI of 188 soybean germplasm varied widely, and five classification criteria for each drought resistance parameter were determined by hierarchical classification method. Among them, Liaodou 15, Liaodou 69, Liaodou 14, Jinzhangzi Huangdou, Zhonghuang 606, Kexin 3 and Koreane 4 were identified as first-grade drought resistant by all evaluation methods. By using GWAS for DI, IDI, WDC and WDI, a total of 15 significantly SNP loci were detected under multiple environments, and the contribution rate of these loci to phenotypic variation ranged from 12.46% to 25.60%. There are 226 annotated genes within 200 kb intervals of upstream and downstream for the significant SNP loci. According to RNA-seq and qRT-PCR analysis of drought-resistant cultivar Liaodou 14 and drought-sensitive cultivar Liaodou 21 under drought stress, a total of 32 annotated genes were significantly differentially expressed by drought stress. Among them, eight genes including Glyma.02G182900, Glyma.04G012400, Glyma.06G258900, Glyma.15G100900, Glyma.01G172600, Glyma.04G012300, Glyma.01G172200 and Glyma.04G010300, encodes calcium-dependent protein kinase, universal stress protein A-like protein, G-type lectin S-receptor-like serine/threonine-protein kinase, protein phosphatase 2C, isoflavone reductase, isoflavone reductase homolog, auxin-like protein, and bZIP transcription factor, respectively. 【Conclusion】 Seven germplasm were identified from 188 soybean germplasm by comprehensive application of different drought tolerance parameters. A total of 15 SNP loci significantly associated with drought tolerance parameters were identified by GWAS, and eight candidate genes were identified.

【Objective】 Wild Arachis species containing many elite disease and insect resistant genes are an important gene pool for the improvement of cultivated peanut A. hypogaea L., so the introduction of chromatin from wild species into cultivated peanut remains an important task for distant hybridization of peanut. Unfortunately, only a few wild species have been successfully involved in the development of interspecific hybrids, despite the existence of a huge amount of wild germplasm resource. The wild species A. sp. 30119 contains multiple disease resistance. However, no interspecific hybrid between it and the cultivated peanut has been reported.【Method】 After crossing allotetraploid peanut cultivar Baitu 131 with diploid wild species A. sp. 30119 and followed by the embryo rescue, the interspecific hybrid F₁ (W1212) was obtained. However, interspecific hybrid F₁ did not produce seed when selfed. In order to reveal the reason for infertility and continue the generation, the chromosome number of root tip cells was counted and chromosome pairing in pollen mother cells during meiosis of W1212 observed. The chromosome of W1212 was doubled through colchicine treatment during the in vitro culture W1212 plantlet. Finally, we harvested four one-seeded pods from the established W1212 plants; one of the pods undergone in vitro cultured and a number of plants were established from the culture and named as Am1212. The chromosome composition of Am1212 was analyzed by sequential GISH/FISH and SSR marker. Additionally, phenotypic characteristics of Am1212 were investigated. The metaphase chromosome numbers of 8 randomly selected F₃ plants were analyzed by rDNA FISH to evaluate the genetic stability of Am1212.【Result】 The average chromosome configuration during meiosis of pollen mother cells of W1212 was 1Ⅲ+6Ⅱ+15Ⅰ, and the abnormalities in chromosome pairings lead to the high sterility of F₁ plants. The pollen viability of peg-setting branches of W1212 was significantly improved after chromosome doubling treatment. Sequential GISH / FISH of Baitu 131, A. sp. 30119 and Am1212 indicated that A. sp. 30119 may be a diploid with A genome. Am1212 has 60 chromosomes consisting of all chromosomes of both Baitu 131 and A. sp. 30119, which confirmed its nature of a hexaploid hybrid, but 37.5% F₃ plants derived from Am1212 exhibited chromosome number variation. After conducting the screening of SSR molecular markers and phenotypic investigation, we obtained 17 dominant or co-dominant markers for specifically tracking wild species chromosomes and clarified the genetic characteristics of Am1212.【Conclusion】 In this study, we successfully created a new hexaploid peanut Am1212 which incorporated A. sp. 30119 chromatin. However, Am1212 exhibited instability in chromosome numbers and inherited unacceptable agronomic traits from wild species, such as small pods. Therefore, it is necessary to develop more accurate and efficient chromosome manipulation techniques to minimize the unfavorable gene linkage and generate alien chromosomal lines that possess compensatory effects and favorable traits for future breeding purposes.

【Objective】 The aim of this study was to develop functional-structural models of maize-soybean intercropping with different planting patterns and row orientations, so as to provide the support for analyzing the yield advantages, growth and developmental patterns, and the effects of planting patterns and row orientations on light interception, light distribution, and radiation use efficiency.【Method】 In this study, one year maize-soybean field experiment with two planting patterns (sole crop and 2:2 MS) and three row orientations (North-South orientation, East-West orientation and Control orientation (Lishu original planting orientation: south-west 40)) was conducted to analyze the effects of planting pattern and row orientation on the performance of biomass, yield and plant architecture. The three-dimensional functional-structural plant (FSP) model was used to simulate crop growth, development, structure and light interception in different planting patterns and row orientations, and to quantify the effects of planting patterns and row orientations on light interception and radiation use efficiency. Row orientation with high light interception was also explored using the FSP model.【Result】 The grain yield land equivalent ratio (LER) under 2:2 MS was the highest in NS orientation (1.20±0.07) and the lowest in EW orientation (1.16±0.09). The FSP model well simulated the growth and development of maize and soybean in different planting patterns and row orientations. Compared with the measured values in the maize field experiment and the simulated values, the root mean square error (RMSE) was 0.09-0.14 m for plant height, 0.04-0.08 m²·plant^-1 for leaf area per plant and 0.07-0.12 for the fraction of light interception; for soybean, the RMSE was 0.07-0.09 m for plant height, 0.02-0.04 m²·plant^-1 for leaf area per plant and 0.09-0.10 for the fraction of light interception. The accumulated light interception for 2:2 MS in Control orientation was the highest, which was (758.48±1.00) MJ·m^-2. Compared with the Control orientation, the radiation use efficiency reduced 7.18% for NS orientation and 10.57% for EW orientation.【Conclusion】 Intercropping increased maize biomass and yield, but reduced soybean biomass and yield. Row orientation had a significant effect in maize-soybean intercropping system. Soybean adapted to the shading by changing morphological characteristics, such as leaf size, internode length, and petiole inclination, to increase the amount of light and optimize the photosynthetic efficiency, which was ultimately converted into an increase in yield. The planting row orientation had a great effect on the light interception, the radiation use efficiency and light interception of the intercropping system showed that the control orientation was better than NS orientation and EW orientation. The results of this study would help to optimize field management and provide the data and technical support for explaining the rational interception and distribution for maize-soybean intercropping in different row orientations.

【Objective】 This study aimed to clarify the response of maize growth and yield with different nitrogen application rates to intercropped green manure, so as to provide the basis for establishing maize production pattern with nitrogen fertilizer saving via green manure in arid irrigation area.【Method】 A split plot experiment design was adopted, and two planting patterns of maize intercropping with common vetch (MV) and sole maize (SM) were set up in the main plot. Five nitrogen application rates were set up in the split plot: the recommended nitrogen application rates were N360: 360 kg N·hm^-2, application rates reduced with 25% (N270): 270 kg N·hm^-2, and that reduced with 50% (N180): 180 kg N·hm^-2, reduced with 75% (N90): 90 kg N·hm^-2, and no nitrogen application (N0). Leaf area index (LAI), daily leaf volume (LAD), light energy utilization rate, dry matter accumulation and yield of maize were investigated.【Result】 In 75-150 days after maize emergence, the LAI, total LAD and light use efficiency of maize with reduced nitrogen application rate (N270, N180, N90, N0) were increased by intercropped green manure. The maize LAI, total LAD and light use efficiency under M||V with N270, N180, N90, and N0 were significantly increased by 9.8%, 8.2% and 4.6% than that under SM, respectively. The maize LAI, total LAD and light use efficiency under M||V with N270 was not different with that with N360, in 75-150 days after maize emergence, and which was greater than that of other treatments. Somehow, the maize LAI, total LAD and light use efficiency of SM was decreased with reduced nitrogen application rate. The dry matter accumulation of maize under N270, N180, N90, and N0 was significantly increased by intercropped with green manure than that of sole maize, in 90-150 d days after maize emergence, which was increased by 4.6%. In 75-130 days after maize emergence, the growth rate of maize under M||V was significantly increased by 5.9% compared that with SM. With the same reduced nitrogen application rate (N270, N180, N90, and N0), the maize grain yield under M||V was significantly increased by 8.5% than that under SM. The grain yield of intercropped maize under N270 was significantly higher than that of sole maize under N360. Compared with SM, the kernel number per ear and 1000-grain weight of maize under M||V were significantly increased by 6.0% and 6.3%, respectively. The results of the fitting curve showed that the greatest grain yield of maize intercropped with green manure was 14 876.4 kg·hm^-2 with nitrogen application rate 261.4 kg·hm^-2. While the greatest grain yield of sole maize was 14 012.5 kg·hm^-2 with nitrogen application rate of 348.6 kg·hm^-2. The effect of reducing nitrogen application on the fresh yield and nitrogen accumulation of green manure was significant. The fresh yield of green manure under M||VN270 was significantly higher than that under M||VN360, M||VN90 and M||VN0 by 3.8%, 4.6%, and 9.7%, respectively, while the nitrogen accumulation with M||VN 270 was significantly higher than that with M||VN90 and M||VN0 by 5.3% and 11.9 %, respectively. The total dry matter accumulation of maize with reduced nitrogen applied rate was increased by intercropped green manure, and then the number of grains per ear and thousand grains weight of maize was increased. Therefore, the intercropped maize could obtain a greater level of grain yield with the condition of reduced nitrogen application rate.【Conclusion】 The treatment of 25% reduced nitrogen rate with intercropped green manure could make maize obtain higher yield than sole maize with the recommended nitrogen application rate. This pattern could be used as a recommended production method for chemical nitrogen fertilizer reduced application of maize in the research region and even similar ecological region.

【Objective】 5-Oxoprolinase (OXP) is one of the six core enzymes in the γ-glutamine cycle. The objective of this study is to characterize the OXP gene of Fusarium oxysporum, clarify its relationship with the pathogenicity of F. oxysporum, and to provide a theoretical basis for the analysis of the molecular mechanism of F. oxysporum pathogenicity and the prevention and control of cotton wilt.【Method】 Bioinformatics methods were used to identify the FoOXPs from the genome of F. oxysporum and analyze their gene structure, domains of the encoded proteins, chromosomal localization and evolutionary relationships. The phenotypes of F. oxysporum after FoOXP2 mutation were analyzed by using knockout mutant and complementary strain and the pathogenicity differences between the mutant and wild-type strains on cotton seedlings were detected. Furthermore, the disease grade rate and disease index on cotton were investigated by using host-induced gene silencing (HIGS) technology. The fungal biomass in cotton and expression of FoOXP2 in cotton stems transformed with interfering fragments of the FoOXP2 were examined by real-time quantitative PCR (qRT-PCR).【Result】 A total of two FoOXPs (FoOXP1 and FoOXP2) were identified in the F. oxysporum genome with coding sequence lengths of 4 080 and 3 921 bp, encoding 1 359 and 1 306 amino acids, respectively. Their protein molecular weights are 14.90 and 14.07 kDa, and theoretical isoelectric points are 5.73 and 5.30, respectively. The FoOXP1 protein is located in the mitochondria and the FoOXP2 protein is located in the cytoskeleton. FoOXP1 and FoOXP2 locate on chromosome JH657921 and chromosome JH657938, do not form gene clusters, with a sequence similarity of 52.00%. Phylogenetic analysis revealed that FoOXP1 and FoOXP2 belonged to two subgroups. Compared with the wild-type strain, the FoOXP2 knockout mutant strain showed significantly lower spore production and spore germination, loss of penetration ability, and increased tolerance to CR and sorbitol, but was more sensitive to cell wall stress (SDS and CFW), oxidative stress (H₂O₂), and osmotic stress (NaCl and KCl). Moreover, the pathogenicity on cotton was significantly reduced. The results of the HIGS assay illuminated that after 14 and 21 d of inoculation, the incidence of FoOXP2 silenced cotton plants was significantly reduced, whose disease indexes (17.3 and 40.2) were significantly lower than those of the control (28.2 and 77.1). The expression of FoOXP2 and fungal biomass were significantly lower than those of the control.【Conclusion】 The FoOXP2 positively regulates the pathogenicity of F. oxysporum and may play an important role in host-pathogen interactions.

【Background】MicroRNA-like RNAs (milRNAs) are a class of regulatory factors commonly found in fungi with similar generation and action mechanism as plant and animal microRNAs, which are widely involved in their growth and development, as well as in life activities such as infection and pathogenesis of plant pathogenic fungi. The apple Valsa canker caused by Valsa mali is the most destructive disease affecting apple production.【Objective】 The research aims to explore the function and mechanism of Vm-milRN7 in regulating the pathogenicity of V. mali, and to provide a theoretical basis for targeted disease resistance breeding of apple Valsa canker.【Method】 Vm-milRN7 precursor overexpression vector was constructed by amplifying Vm-milRN7 precursor sequence using genomic DNA of strain 03-8 as a template; upstream and downstream sequences of Vm-milRN7 precursor were amplified and Vm-milRN7 precursor knockout mutants were constructed by using Double-joint PCR technique. The Vm-milRN7 precursor overexpression strains and knockout mutants were constructed by PEG-mediated protoplast transformation. The vegetative growth rate of Vm-milRN7 precursor overexpression strains and knockout mutants was determined by cultivation on PDA medium, and the pathogenicity of these strains was verified by inoculation on apple twigs and leaves. The regulatory relationship between Vm-milRN7 and its potential target gene Vm-09496 was identified by qRT-PCR and co-infiltration experiment in Nicotiana benthamiana leaves; protein sequence characterization and phylogenetic analysis of Vm-09496 were performed using bioinformatics software. In order to analyze its function, Vm-09496 knockout mutants and complement strains were created and their phenotypes were characterized.【Result】 PEG-mediated genetic transformation was used to create Vm-milRN7 overexpression strains and knockout mutants. Vm-milRN7 overexpression strains showed no apparent alteration in vegetative growth rate compared with that of the wild-type strains, whereas the knockout mutants had a significantly lower vegetative growth rate. Compared with the wild-type strains, the overexpression strains showed a significant increase in the pathogenicity of V. mali on apple leaves, while the knockout mutants showed a significant decrease in the pathogenicity of V. mali on apple leaves and twigs. Further, qRT-PCR and co-infiltration in N. benthamiana leaves assay showed that Vm-milRN7 inhibited the expression of its potential target gene Vm-09496. Bioinformatics analysis revealed that the gene encodes an imaginary protein and is evolutionarily most closely related to VP1G_09956 in V. pyri. In order to analyze its function, the Vm-09496 knockout mutants and complement strains were created, and the pathogenicity of the knockout mutants on both twigs and leaves was significantly increased compared with that of the wild-type strain, while the vegetative growth rate and pathogenicity of the complement strains recovered to the wild-type level.【Conclusion】 Vm-milRN7 may be involved in the pathogenity of V. mali by regulating the expression of the target gene Vm-09496. The target gene Vm-09496 is an important endogenous gene affecting V. mali infection and negatively regulates V. mali pathogenicity.

【Objective】 Conservation tillage is an important measure for restoring and enhancing soil fertility, and soil organic carbon (SOC) plays a crucial role in maintaining soil fertility, supporting crop growth, and protecting soil environment. However, there is currently a lack of long-term monitoring platforms for conservation tillage in China, so using modeling methods can help study SOC dynamics under long-term conservation tillage. 【Method】 A long-term tillage experiment was established in the black soil region in 2001 with three treatments: no-tillage (NT), moldboard plow (MP), and ridge-tillage (RT). The structures and parameters of process-based models (RothC, AMG model) and statistical models (MLPNN model) were optimized. The changes in SOC under long-term conservation tillage were simulated and compared. The effectiveness of different models in simulating and predicting the SOC dynamics under conservation tillage was evaluated, and the long-term response and influencing factors of SOC in black soil in Northeast China to conservation tillage were revealed. 【Result】 After optimizing parameters for carbon pool allocation, errors of the RothC and AMG models were significantly reduced. During the first 11 years (2001-2012) of conservation tillage, there was no significant difference in the simulation of SOC between RothC and AMG models, indicating that the structural complexity of process models does not have significant impacts on the simulation results for relatively short term. The simulation results of the statistical model MLPNN were similar to process models, proving the application of statistical models in small-scale regions. Over the next 100 years, RothC and AMG models predicted similar trends in SOC changes, but AMG model significantly overestimated the increase in SOC stocks, which may be attributed to SOC saturation and the influence of tillage practices. Both RothC and AMG models showed high sensitivity to carbon input, but they responded differently to climate and soil factor changes. 【Conclusion】 It is necessary to choose appropriate models based on local conditions while using models to simulate SOC in long-term conservation tillage. For short-term prediction of SOC under conservation tillage, a relatively simple AMG modelcan be used, while for long-term prediction, a more complex RothC model can be used. Under specific conditions, statistical models show similar effects to process models in simulating soil organic carbon at a small-scale regions, such as plots and fields.

【Objective】 The aim of this study was to explore and analyze the differences in yield, panicle differentiation and degeneration, soil microbial activity, and response of soil alkali-hydrolysable nitrogen to simplified panicle fertilization among different rice varieties under the condition of wheat straw return (SR). 【Method】 As test materials, two cultivars were selected, including late maturing medium japonica rice Nanjing 9108 (NJ 9108) and indica rice Yangdao 6 (YD6). Rice yield, spikelet differentiation, and degeneration were evaluated under the interactive conditions of SR and simplified panicle fertilization (0﹕0, no panicle fertilization; 2﹕0, full application of spikelet-promoting fertilizer; 1﹕1, equal application of spikelet-promoting and protecting fertilizers; 0﹕2, full application of spikelet-protection fertilizer). The nutritional basis of rice spikelet differentiation and degeneration was analyzed in terms of nutrient release from straw decomposition, alterations in soil microbial communities and enzyme activity, and soil alkaline nitrogen content. 【Result】 (1) After SR, the average yield of NJ 9108 and YD 6 increased by 4.2% and 3.2%, respectively. Under panicle fertilization treatments, the highest yield for NJ9108 and YD6 was achieved under the 2﹕0 and 1﹕1 treatment, respectively. After no wheat straw return treatment (NR), the yield of both varieties was highest under the 1﹕1 treatment. The yield trend of panicle fertilization treatments was consistent within the range of 180-360 kg N·hm^-2. (2) After SR, the initial 0-30 days were a period of rapid decomposition, with the rapid release of carbon and nitrogen from the straw. At 30 days, the average number of bacteria, fungi, and actinomycetes in the soil increased by 179.2%, and the average activity of urease, acid phosphatase, and sucrase increased by 88.8%. During the period of 40 to 60 days, the straw's decomposition and carbon-nitrogen release rates diminished, and the number of microorganisms and enzyme activities decreased significantly. Decomposition and carbon-nitrogen release of straw essentially stalled between 60 and 90 days, while the number of microorganisms and enzyme activities decreased gradually. From 10 to 40 days after SR, the soil's alkali-hydrolysable nitrogen content decreased by an average of 4.8%, while it increased by an average of 5.2% between 50 and 90 days. (3) After SR, the increase in soil alkali-hydrolysable nitrogen caused an increase of 1.4% in the average number of spikelets differentiation, a decrease of 12.3% in the average number of spikelets degeneration, but an increase of 4.4% in the average number of surviving spikelets. Rice harvest increased primarily due to an increase in the number of spikelets per panicle (the number of surviving spikelets per panicle). After SR, the 2﹕0 treatment reduced the rate of spikelet degeneration in NJ9108 and YD6 relative to NR by 23.5% and 7.6%, respectively. The number of spikelet differentiation and degeneration of NJ9108 increased by 8.9 and 5.7 spikelets per panicle under the 2﹕0 treatment relative to the 1﹕1 treatment, whereas Yangdao 6 increased by 6.8 and 11.6 spikelets per panicle, respectively. As the increase in the number of spikelets differentiation was greater than the increase in the number of spikelets degeneration, NJ9108 had the highest number of surviving spikelets under the 2﹕0 treatment, while YD6 had the highest number under the 1﹕1 treatment. 【Conclusion】 Wheat straw return increased rice yield, with NJ 9108 achieving the highest yield under the full application of spikelet-promoting fertilizer and Yangdao 6 achieving the highest yield under the equal application of spikelet-promoting and protecting fertilizers. Those factors that contributed to the increase in yield were mainly due to a significant reduction in the rate and number of spikelets degeneration and an increase in the number of spikelets per panicle. The decrease in the rate of spikelets degeneration for NJ 9108 was greater than that for YD6, which was the main reason for the difference in their response to different panicle fertilization treatments in terms of the number of surviving spikelets.

【Objective】 Crop yield increases and soil organic matter decreases when double rice cropping system shifted to wet and dry rotation cropping system, but little information is known that the effects of chemical fertilizer nitrogen combined with different organic materials on crop yield, nitrogen use efficiencies and organic matter content under the wet and dry cropping system.【Method】 The maize and rice rotation was regarded as object, five treatments were set up, including no nitrogen fertilizer applied (CK), only chemical fertilizer applied (NPK), NPK plus straw return (NPKS), NPK plus manure (NPKM) and NPK plus biochar (NPKB) in purple clayey soil and reddish clayey soil in Dongting lake plain from 2015 to 2021. The changes of yield, nutrient use efficiency, soil carbon and nitrogen content as well as carbon and nitrogen balance under different fertilization treatments were explored. 【Result】 The average maize yield, rice yield and total annual yield in the six-year in purple clayey soil and reddish clayey soil were 5.7, 7.3 and 12.9 t·hm^-2, respectively. Moreover, the three yields above in purple clayey soil were slightly higher than that reddish clayey soil, though the differences in both soils were not significant. Compared with the NPK treatment, NPKM treatment significantly (P<0.05) increased the average yields in maize season or rice season in the two soils (P<0.05) by 10.6% and 4.20%, respectively. Among all the treatments, NPKM treatment had the maximum yield in the maize season, and the value was 6.0 t·hm^-2; and NPKB treatment had the maximum yield in the rice season, and the value was 7.5 t·hm^-2. The six-year average annual total yield under NPKM and NPKB treatments was significantly higher (P<0.05) than that under other treatments, respectively, but the difference between NPKM and NPKB treatments was not significant. Compared with the other treatments, NPKM treatment significantly (P<0.05) improved the chemical fertilizer nitrogen recovery efficiency, agronomic efficiency and partial productivity in maize, rice, the six-year average values of maize season were 66.3%, 39.5 kg·kg^-1 and 56.0 kg·kg^-1, respectively, and the six-year average of rice season was 53.8%, 21.9 kg·kg^-1 and 68.6 kg·kg^-1, respectively. NPKB treatment had significant higher chemical fertilizer N agronomy efficiency and partial productivity than the NPKS and NPK treatments in maize and rice seasons, and compared with NPK treatment, the nitrogen recovery rate of maize was also significantly improved. Soil organic carbon and total nitrogen content decreased significantly from the fourth years (the year of 2019). Compared with the soil organic carbon and nitrogen content between the beginning of the experiment (2015) and 2021, the annual average soil organic carbon in all the N applied treatments in purple clayey soil and reddish clayey soil decreased by 1.8 and 0.7 g·kg^-1, and total nitrogen content decreased by 0.4 and 0.1 g·kg^-1; the NPKM treatment in both the soils had the lowest decrease of soil organic carbon and total nitrogen, and the NPKB treatment was the second. The loss of soil organic carbon and total nitrogen in the NPKM treatments were the lowest, which were 0.48 t C·hm^-2·a^-1 and 94.7 kg N·hm^-2·a^-1, respectively.【Conclusion】 After the double rice cropping system shifted to wet and dry rotation cropping system, the chemical fertilizer nitrogen combined with manure and biochar could increase crop yield and hold back the decrease of soil organic matter, NPKM treatment had the maximum average maize yield and NPKB treatment had the maximum average rice yield during the experimental period.

【Background】 The number of branches on an apple tree plays a pivotal role in its environmental adaptability, growth, survival, and resource competition. In production practice, the apple cultivars with more branches can better meet the needs of pruning and shaping, not only do they facilitate timely adjustments to the tree's structure based on local conditions, but also they ensure a uniform distribution of fruit-bearing branches, thereby guaranteeing both fruit quantity and quality. 【Objective】 In this study, by using the top buds and lateral buds of more-branched cultivar Huaxing and fewer-branched cultivar Huashuo at the same developmental stage, the transcriptome sequencing was carried out to identify key genes regulating the ability of branching, as well as to elucidate the potential mechanism underlying branching phenotype, and finally to provide the theoretical basis for improving the branching ability and yield of apple. 【Method】 The lateral and terminal buds of Huashuo and Huaxing were sampled for RNA-seq. By differential expressed gene (DEG) and analysis and weighted gene co-expression network (WGCNA) analysis, the core candidate genes that were responsible for branch number difference were identified and further demonstrated their function by Arabidopsis transformation.【Result】 A total of 2 920 DEGs were identified from the comparison between the terminal buds, while 5 127 DEGs were screened out from the comparison between the lateral buds. DEGs were mainly enriched in phytohormone signaling pathway. Notably, the auxin signaling pathway, and strigolactone signaling pathway seemed to have the closest connection with the branching ability of apple with the related genes encoding MdIAA3, MAX2, TCP, and JAZ, which showed significant differences between lateral buds. Furthermore, DEGs annotated to cell cycle and cell wall modification families, such as CYC (Cyclins), CDK (Cyclin-dependent kinase), and EXPA (Expansin), also demonstrated a positive correlation with apple branching ability. In addition, those candidate genes obtained from WGCNA analysis also showed high possibility of getting involved in branch number regulation. Heterologous transformation of Arabidopsis with MdIAA3 could significantly enhance the overall growth, increased pod number and branching number of Arabidopsis. 【Conclusion】 Through comprehensive research, 13 candidate regulatory genes were identified that potentially played a crucial role in transcriptional regulation for branch number. MdIAA3 was ectopically expressed in Arabidopsis, which significantly promoted plant growth and branching ability. It was plausible that these genes regulated branching through processes, such as cell differentiation and development, cell wall modification, auxin, and strigolactone signaling pathway.

【Objective】 Fruit sensory quality is the most important factor in determining the competitive edge in the fruit market. The aim of this study was to establish a comprehensive sensory quality evaluation method for citrus fruits by analyzing Orah mandarin (Citrus reticulata Orah) fruits produced in nine different regions and showing quality differences. In addition, this study was aimed to identify sensory quality differences, consumer preference, and metabolites closely linked to citrus sensory attributes in Orah mandarin from different regions. This study could provide the theoretical support and digital method for citrus breeding, practical production and marketing. 【Method】 Firstly, evaluators assessed each sensory attribute and weight of fruit samples, and the fuzzy mathematics was used to derive the weight ranking of different sensory attributes. The samples were then ranked and grouped based on comprehensive sensory evaluation. Furthermore, the physical and chemical indexes were measured, and metabolites related to fruit flavor were analyzed by using GC-MS and HPLC, including soluble sugars, organic acids, amino acids, and flavonoids. OPLS-DA was used to analyze the main differential metabolites between samples from different groups. The relationship between sensory attributes and metabolites was determined by using Pearson correlation analysis. Finally, the important biomarkers reflecting the flavor quality of Orah mandarin were identifued. 【Result】 The sensory attribute weights of Orah mandarin were determined as pulp sweetness>pulp acidity>pulp mastication>fruit color>fruit aroma>fruit shape. Conventional solid-acid ratio was not suitable for accurate classification of the intrinsic quality of Orah mandarin samples. Therefore, based on comprehensive sensory quality, the nine Orah mandarin samples were divided into a high sensory quality group with a score larger than 60 and a low sensory quality group with a score smaller than 60. The OPLS-DA analysis revealed three key compounds (L-glutamic acid, hesperidin, and L-valine) distinguishing high and low sensory quality groups. Futhermore, the pearson correlation analysis indicated that the levels of α-ketoglutaric acid, L-glutamic acid and hesperidin were negatively correlated with sensory quality, sweetness and acidity. 【Conclusion】 Fuzzy mathematics was effectively used to evaluate the comprehensive quality of Orah mandarin. The results indicated that consumers were more concerned in pulp sweetness and acidity; L-glutamic acid and hesperidin might be trait components reflecting the flavor quality of Orah mandarin.

【Objective】 In oilseeds, lipids are mainly stored in the organelles called oil bodies. Tree nuts, such as walnut and hazelnut, were important oilseed crops. Among the 5 selected tree nuts, the differences in morphology, structure and stability of their oil bodies were evaluated and discussed, which could provide the new ideas for the utilization of the nut oils.【Method】 5 tree nuts were used as materials, including walnut, almond, hazelnut, pecan, and pine nut. The morphology and size of the oil bodies inside the cells of different nut seeds were observed and compared by employing transmission electron microscope. The oil body membrane proteins were separated by SDS-PAGE, followed by the LC-MS/MS identification of the protein bands. The oil body membrane phospholipids, as well as the intrinsic triacylglycerols, were also analyzed through lipidomics. The stability of oil bodies was evaluated by analyzing their changes in morphology peroxide values and thiobarbituric acid values during storage under room temperature.【Result】 The cells of the nut seeds were occupied by the oil bodies and proteosomes. The asymmetric spheroid-shaped oil bodies were covered by intact membranes. The pecan oil body had the largest average diameter (2.34±0.48) μm, while the almond oil body had the minimum (1.21±0.19) μm. For all nut samples, oleosin was the most important oil body membrane protein, accounting for 72.76%-84.15% of the total amount of membrane proteins. Oleosin had a narrow molecular weight distribution of 14.7-18.8 kDa, yet the numbers of oleosin isomers were quite different. Caleosin accounted for 14.34%-4.96% of the total amount of membrane proteins, and its molecular weight in different nuts was approximately 26.5-27.1 kDa. No caleosin isomer was found in each nut sample. Steroleosin, accounted for 8.95%-12.89% of the total amount of membrane proteins, was identified only in walnut, pecan and pine nut oil bodies. The oil bodies of the 5 tree nuts had different triacylglycerol compositions but similar membrane phospholipid compositions. Phospholipidine (PS) and phosphatidylcholine (PC) were the most important oil body membrane phospholipids, accounting for 67.91%-75.06% of the total amount of membrane phospholipids. The proportion of unsaturated fatty acyl chains in membrane phospholipids was 69.64%-74.52%, while 38.64%-45.15% of the fatty acyl groups were oleoyls. The hazelnut oil body showed the highest stability at room temperature. During storage, the oil bodies aggregated and fused gradually, accompanied by an increasing degree of lipid oxidation. Eventually the phase separation phenomenon in oil body emulsions was observed.【Conclusion】 Among the oil bodies from 5 tree nuts, the pecan oil body was the largest in size, while the hazelnut oil body was the most stable. The different tree nut oil bodies had similar constituents of membrane proteins and membrane phospholipids, but there were significant differences in the number of oleosin isomers, triacylglycerol compositions and constituent proportions. The ratio of lipid content to oleosin, as well as the ratio of oil body membrane phospholipids to oil body membrane proteins, might have important influences on the size and stability of the oil bodies.

【Objective】 This study aimed to measure the enzymatic hydrolysate gross energy (EHGE) of chicken for wheat, paddy, and brown rice ingredients using a monogastric simulated digestion system, and it also aimed to correlate these measurements with the chemical composition of these ingredients. Moreover, the study sought to establish predictive equations for chicken metabolizable energy values based on the EHGE values and the grain ingredients’ chemical compositions. The findings would provide a reference for the rapid prediction of the metabolizable energy value of grain ingredients for chickens. 【Method】 The EHGE values of nine samples from three sources of wheat, paddy, and brown rice ingredients were measured. Five replicates were set for each grain sample, with one digestion tube per replicate. The apparent metabolizable energy values (AME) and true metabolizable energy values (TME) of the same batch of ingredients were also measured by the free feeding method (FF) and the tube-feeding method (TF). A linear regression model was then used to establish predictive equations for AME and TME based on chemical composition and EHGE values. 【Result】 (1) Based on dry matter basis, the EHGE values of wheat, paddy, and brown rice from the three sources were 14.46, 14.63, and 14.80 MJ·kg^-1; 12.52, 13.59, 13.40 MJ·kg^-1, and 14.74, 15.10, 15.23 MJ·kg^-1, respectively. (2) Ash and neutral detergent fiber exhibited a negative correlation with AME (AME_FF and TME_FF) and TME (AME_TF and TME_TF) measured by both FF and TF methods (P<0.01). EHGE exhibited a significant positive correlation with AME_FF, TME_FF, AME_TF, and TME_T measured by both methods (P<0.01), with correlation coefficients of 0.801, 0.864, 0.807, and 0.866, respectively. (3) Compared with the metabolizable energy prediction equations established by EHGE, the prediction equations based on chemical composition had higher coefficients of determination (R²) and lower residual standard deviations (RSD). For AME_FF and TME_FF, Ash was the best predictor, with prediction equations: AME_FF = 16.728-0.842 × Ash (R²= 0.809, RSD = 0.826, P = 0.001), and TME_FF = 16.812-0.842 × Ash (R²= 0.816, RSD = 0.806, P = 0.001). On the other hand, for the AME_TF and TME_TF variables, NDF was identified as the best predictor. The prediction equations for AME_TF and TME_TF were AME_TF=16.106-0.157×NDF (R²=0.907, RSD=0.523, P<0.001), and TME_TF=17.654-0.157×NDF (R²=0.903, RSD= 0.534, P<0.001), respectively. 【Conclusion】 The EHGE of wheat and brown rice was higher than that of paddy, and there was a good correlation between the EHGE values of the three grain ingredients and the metabolizable energy values measured by the in vivo method. The prediction model for the AME and TME of grains based on chemical composition was superior to the prediction model based on EHGE.

【Objective】 Body size traits are the primary indicators for evaluating avian growth characteristics. By selecting molecular markers and candidate genes related to body size traits in Wenchang chickens, this study could provide the theoretical support for deciphering the genetic mechanisms and molecular breeding of body size traits. 【Method】 Three generations of Wenchang chicken lines in Hainan Province (n=2 024) were used in this study. Five body size traits were measured on each chicken at market age, including shank length, shank girth, body slope length, keel length, and chest width. Blood samples were collected for DNA extraction, followed by sequencing and genotyping using the "Jingxin No.1" 55 K chip. Genome-wide association analysis was conducted using GEMMA and PLINK software to identify SNP loci and important candidate genes associated with body size traits. LD analysis was performed to identify haplotypes significantly associated with body size traits. 【Result】 Phenotypic data showed that, at 113 days of age, Wenchang cockerels had average shank length of 8.64 cm, shank girth of 0.46 cm, body slope length of 19.73 cm, keel length of 12.32 cm, and chest width of 6.81 cm. Wenchang hens had average shank length of 6.98 cm, shank girth of 0.40 cm, body slope length of 17.79 cm, keel length of 10.45 cm, and chest width of 6.24 cm. After quality control, 42 206 SNPs and 2 024 individuals were retained for further analysis. PCA analysis using PLINK software revealed some dispersion among the three generations, prompting the inclusion of the top three principal components as covariates in the GWAS analysis to correct for population structure effects. The GWAS results identified 19 SNPs significantly or suggestively associated with shank length (P value=2.17789E-06/4.35578E-05), 23 SNPs associated with shank girth, 7 SNPs associated with body slope length, and 2 SNPs associated with keel length. No SNPs significantly associated with chest width were identified. Annotation of significant loci identified 16 candidate genes related to body size traits, including LDB2, NCAPG, FAM184B, and KCNIP4. LD haplotype analysis revealed 3 significant haplotypes in GGA4, with candidate genes LDB2 and NCAPG annotated in significant block loci. Regarding the shank length trait, two loci, including rs316943436 and rs313978573, were situated within the haplotype block. For shank girth, five loci, namely rs313196946AA, rs316242963, rs315796839, rs313978573, and rs734365522, were located within the haplotype block. In the case of body slope length, only one locus (rs313978573) resides within the haplotype block. 【Conclusion】 Through the GWAS method, those potential candidate genes for shank length, including SEPSECS, LGI2, DHX15, KCNIP4, NCAPG, FAM184B, LDB2, and CC2D2A, were identified. For shank girth, potential candidate genes encompassed FH, TBC1D1, DTHD1, SEPSECS, LGI2, SOD3, PPARGC1A, KCNIP4, NCAPG, FAM184B, CLRN2, LDB2, TAPT1, and CC2D2A. KCNIP4, LDB2, TAPT1, and NRXN3 were identified as potential candidate genes for body slope length, while FAM184B emerged as a potential candidate gene for keel length. In summary, this study established LDB2, NCAPG, and FAM184B as potential functional genes associated with various body size traits, providing the theoretical support for molecular marker-assisted selection in enhancing body performance in Wenchang chickens.

【Objective】Hardness, a structural feature of seed physical dormancy, is an important trait in soybean domestication. Although hardness is beneficial for seeds to survive in unfavorable environments, it will seriously reduce the emergence rate of soybean in the field, and detrimental to yield and processing quality. Analyzing the QTL and candidate genes using bulked segregant analysis sequencing (BSA-Seq), can provide a theoretical reference for understanding the molecular mechanism of hard seededness in soybean.【Method】The hard seed mutant M_zp661 was obtained from the seeds of Zhongpin 661 induced by ethyl methane sulfonate (EMS), and was crossed with cultivated soybean Zhonghuang 13 (male parent) to construct recombinant inbred line (RIL) population. The progeny lines were investigated for seed hardness, water absorption capacity and anatomical structure of seed coats. Two types of extreme lines in the RIL population, with hard seeds or with imbibed seeds, were selected to construct DNA mixed pools respectively, and then BSA-Seq technology was used to detect genotype differences in extreme-mixed pools and parents. Euclidean distance (ED), delta SNP-index, and delta InDel-index methods were applied to associate hard seed genetic loci of soybean. Combining with bioinformatics analysis, transcriptome data of different soybean tissues and gene annotation information, candidate genes within significant association regions were predicted.【Result】In the progenies of M_zp661, all areas of imbibitive seeds had the penetration ability, and the seed volume increased continuously with the soaking time. However, no changes were observed for hard seeds over 36 hours. With the prolonged of soaking time, the seed coat of hard seeds began to shrink locally and gradually spread to other parts, and finally cotyledons recovered their imbibition ability. The hard seed not only has smooth and compact seed coat, but also has regular network structure of cuticle and thicker palisade layer, while numbers of stomata and loose structures, tiny cracks and thinner palisade layer were existed in the imbibed seeds. These results suggest that the seed hardness of M_zp661 may be caused by the impermeability of the seed coat. ED, delta SNP-index and delta InDel-index association analysis methods not only identified the reported seed physical dormancy locus qHS1, but also simultaneously detected the candidate region Chr.06: 45897227-47746047, which contains a total of 189 genes. Further, transcriptome data and gene annotation predicted that Glyma.06G275300, which is specifically and highly expressed in seeds, might be the candidate gene for this associated region to regulate soybean seed hardness.【Conclusion】Seed hardness of soybean mutant M_zp661 was caused by the impermeability of the seed coat, and Glyma.06G275300 was predicted as a candidate gene affecting the structure of seed coat using BSA-Seq.

【Objective】Soluble sugar content is one of the important quality traits of vegetable soybean. The genetic variation and genetic mechanism of soluble sugar content in fresh soybean seeds were studied to provide a basis for germplasm innovation and quality breeding of vegetable soybean.【Method】Using 133 soybean landraces from the Northeast region, the North region, the Huanghuaihai region and the South region, the soluble sugar content of fresh seeds was determined in the three environments of Lianjiang in spring, Fuqing in spring and autumn, in 2021. In combination with 82 187 high-quality SNP markers, the whole genome association analysis of soluble sugar content was conducted based on the mixed linear model MLM (Q+K), and the SNP loci with significantly related to soluble sugar content were identified. The candidate intervals were selected by the significant SNP loci and the extension of 119.07 kb linkage disequilibrium decay distance at both ends. The candidate genes were predicted according to the annotation and tissue expression information of the genes in the candidate intervals.【Result】The variation range of soluble sugar content in fresh seeds under three environments was 3.37-33.84 mg·g^-1, the genetic variation coefficient was 24.59%-32.69%, and the heritability of soluble sugar content was 68.14%. 6, 8 and 22 SNPs were significantly associated with the soluble sugar content of fresh seeds were detected in Lianjiang in spring, Fuqing in spring and autumn, respectively, and phenotypic variation was 12.43%-29.27%. A total of 86 genes were obtained in the candidate regions of 9 significant SNP loci with higher interpretation rate of phenotypic variation, and 9 candidate genes were further screened by gene annotation and tissue expression information. These candidate genes are mainly involved in biological processes such as transcription factors, glycoprotein families and carbohydrate synthesis and transport. Among them, Glyma.01g016500, Glyma.13g042100, Glyma.16g131800 and Glyma.16g155300 were more highly expressed in soybean seeds and pods, which can be used as the most potential candidate genes for soluble sugar in fresh soybean seeds.【Conclusion】Through genome-wide association analysis, 36 SNPs significantly associated with soluble sugar content in fresh seeds were detected, and 9 candidate genes were further screened out, which may be involved in the regulation of soluble sugar content in fresh soybean seeds. Among them, Glyma.01g016500, Glyma.13g042100, Glyma.16g131800 and Glyma.16g155300 can be the key candidate genes for regulating soluble sugar content in fresh soybean seeds.

【Objective】An accurate and rapid indoor evaluation system was established by using soybeans with different resistance levels to Phomopsis seed decay as test materials. And then 170 soybean germplasm accessions were employed to screened out disease-resistant varieties, so as to provide methods and material basis for high-throughput assessment of Phomopsis seed decay in soybean and cultivation of resistant varieties.【Method】In terms of establishing a reliable evaluation method for Phomopsis seed decay, Qihuang 34, Williams, Zhongzuo 09-560, z13-631-2, ZDD26268, Chenxiqingpidou 1 and Tongxianhuangdou were selected as experimental materials. For each soybean accession, the seeds with uniform size and undamaged seed coat were germinated in the dark after disinfection. At different germination stages, the pathogen of Phomopsis seed decay was inoculated for 24 h, 48 h, 72 h and 96 h. The mycelium coverage rate and seed decay rate of seed surface under different infection time were counted to determine the optimal identification period for evaluating Phomopsis seed decay in soybean. Then, the resistance of 170 different soybean germplasms in natural population was identified by using the coverage rate of mycelium on the surface of seeds and the decay rate of seeds as evaluation indexes. The high disease resistance varieties were screened based on 5 disease resistance levels.【Result】The soybean accessions showed the most significant differences in disease resistance levels after 96 h of germination when mycelium coverage rate and seed decay rate of soybean surface were used as evaluation indexes. Further comparison of the incidence of 24 h, 48 h, 72 h and 96 h after infection showed that the difference in disease resistance between different varieties after infection for 72 h was the most obvious. Therefore, it was the most suitable period, 72 h of infection at the bud stage after 96 h of germination, for evaluating the resistance level of different soybean varieties to Phomopsis seed decay. The resistance of 170 soybean varieties to Phomopsis seed decay was identified and classified into five disease resistance grades, namely, high resistance, medium resistance, medium susceptibility, susceptibility and high susceptibility. Among them, there were 30 varieties of grade I (high resistance to disease), 51 varieties of grade Ⅱ (medium resistance to disease), 71 varieties of grade Ⅲ (medium disease susceptibility), 4 varieties of grade Ⅳ (disease susceptibility) and 14 varieties of grade V (high disease susceptibility), idicating that there are extensive variations in the resistance to Phomopsis seed decay of soybean germplasm resources in China.【Conclusion】In this study, the most optimum stage of disease identification was considered as soybean seeds after 96 h germination to infect the Phomopsis longicolla for 72 h. After that, the mycelium coverage rate and seed decay rate of soybean surface were counted as evaluation parameters. The evaluation system has high accuracy and reliability, which can provide an effective method for high-throughput identification of different varieties in the laboratory. And 30 highly resistant varieties were further screened to provide a material basis for the breeding of resistant varieties.

【Objective】Exploring efficient nodulation soybean germplasm adapted to the ecological conditions of the Bashang area, identifying genetic loci and candidate genes regulating soybean-rhizobium symbiotic nodulation, and improving soybean symbiotic nitrogen fixation efficiency.【Method】This study utilized a natural population of 260 soybean germplasms as the research object, rhizobium strain USDA110 was inoculated under outdoor potted conditions in the Bashang of Hebei Province. The single plant nodule number and single plant nodule dry weight data were used as phenotypic values. Combined with genotype data of the 260 germplasms, a genome-wide association analysis was conducted to explore genes related to soybean-rhizobium symbiotic nodulation.【Result】A total of 18 SNPs significantly associated with soybean nodule number were detected, located on chromosomes 2, 7, 8, 13, 18, and 19. Among them, the significant associated locus BARC_2.01_Chr02_43161654_A_G on chromosome 2 was identified as the main locus controlling soybean nodule number (LOD=3.89). Linkage disequilibrium analysis within the 200 kb interval upstream and downstream of this locus containing BARC_2.01_Chr02_43161654_A_G identified 10 candidate genes regulating soybean nodule number. There was a significant difference in the number of nodules among the materials corresponding to different haplotypes of Glyma.02G243200 (P<0.05), the expression pattern of this gene was queried in the SoyBase database, and it was expressed in root hairs, indicating that Glyma.02G243200 may be a key gene influencing soybean nodule number. Additionally, six SNPs significantly associated with soybean nodule dry weight were identified, located on chromosomes 6, 18, and 20. Among them, the significant associated loci BARC_2.01_Chr06_6069381_G_A and BARC_2.01_Chr06_6192925_T_C on chromosome 6 were identified as the main loci controlling soybean nodule dry weight (LOD=3.49 and LOD=3.35, respectively). Linkage disequilibrium analysis within the 100 kb interval upstream of BARC_2.01_ Chr06_6069381_G_A and downstream of BARC_2.01_Chr06_6192925_T_C identified 14 candidate genes regulating soybean nodule dry weight. Haplotype analysis revealed significant differences in nodule dry weight for the genes Glyma.06G079600 and Glyma.06G079900 between different haplotype materials (P<0.01, P<0.001), the expression pattern of this gene was queried in the SoyBase database, and they were expressed in roots, indicating that these two genes may be key genes influencing soybean nodule dry weight.【Conclusion】This study identified a candidate gene significantly associated with nodule number on chromosome 2 and two candidate genes significantly associated with nodule dry weight on chromosome 6, providing new genetic resources and references for genetic improvement of soybean nodulation traits.

【Objective】The aim of the study was to evaluate the differences between rice yield and its components, as well as quality of double cropping early japonica rice which was selected from various accumulated temperature zones in cold region to plant in the lower reaches of the Yangtze River, so as to provide a theoretical basis to select the proper japonica varieties as the double cropping early season rice in this area.【Method】Field experiments were carried out at Taizhou (121°13′ E, 28°78′ N) and Hangzhou (119°94′ E, 30°08′ N) of Zhejiang province in 2018, 2021 and 2022. Six (2018), thirteen (2021) and forty-one (2022) japonica varieties were selected from different accumulated temperature zones in Heilongjiang province, respectively, and the early indica rice Zhongzao 39 was picked out as a control in 2018 and 2022. The differences of productive panicle number, spikelets number per panicle, percentage of filled grain, thousand grains weight, number of spikelets unit area, yield, and harvest index were analyzed among double-cropping early japonica and indica rice; the quality indexes were compared among this two types rice too, such as head rice rate, diaphaneity, gel consistency, amylose content, chalkiness degree, and chalky grain rate.【Result】The harvest dates of early japonica rice with beforehand sowing were about 0-15 days earlier than that of local double-season early indica rice. The total mean yield of early japonica rice was 6 637.77 kg·hm^-2 in 2018; and the yield of Kongyu 131 were the highest with 7 724.70 kg·hm^-2. Moreover, the field production verification in 2022 suggested that the yield of Kongyu 131 could reach 7 194.77 kg·hm^-2. The averages of chalkiness degree, diaphaneity, gel consistency and amylose content in all varieties met the quality of second-class edible rice variety criterion, but the head rice rate was low. The total mean yield early japonica rice was 6 630.45 kg·hm^-2 in 2022, in order as follows: Longken 257 (8 324.99 kg·hm^-2), Longken 263 (8 170.94 kg·hm^-2), and Liandao 1 (8 108.34 kg·hm^-2). Compared with Zhongzao 39, the productive panicle number in early japonica rice were higher, however, the spikelets number per panicle, percentage of filled grain, thousand grains weight were lower than the control, which induced the yield decrease of 54.75%-93.28%. The average yield of the third accumulated zone was higher than that of other accumulated zones due to the relative superior percentage of filled grain. The correlation analysis within yield and its components of different japonica cultivars showed that, the yield had significantly positive correlation with productive panicle number (P<0.05) and number of spikelets unit area (P<0.01).【Conclusion】It was practicable to plant double cropping early japonica rice varieties in the Yangtze River area selected from different accumulated temperature zones in Heilongjiang province, confirmed by appropriate performances on growth duration, yield and quality. It was suggested that Kongyu 131, Longken 257, Longken 263, and Liandao 1 could be selected as double cropping early japonica rice for the next large-scale demonstration planting.

【Objective】In order to explore the effects of fertilization on soil nutrients and wheat (Triticum aestivum L.) root growth, and to shape a good root architecture, so as to provide a theoretical basis for scientific fertilization and high-yield and high-efficiency production of wheat field.【Method】The experiment was conducted in Yuanyang Scientific and Educational Park of Henan Agricultural University from 2021 to 2023. The pool planting positioning experiment is adopted. And three fertilization treatments (F₀: no fertilization; F₁: shallow application of N, P, K fertilizer; F₂: 1/3 shallow application plus 2/3 deep application of N, P, K fertilizer) and three irrigation treatments (W₁: prior to sowing irrigation; W₂: prior to sowing irrigation plus irrigation at jointing stage; W₃: prior to sowing irrigation plus irrigations both at jointing and anthesis). A total of 9 treatment combinations were used to determine concentration dynamics of soil nutrients and root morphological and physiological traits at different soil layers within 0-100 cm.【Result】Under different irrigation frequencies, the concentrations of available N, P, K nutrients were relatively high in top soil layer and decreased with the soil depth. In the soil layer of 0-60 cm, the trend of concentrations of available N, P, K nutrients under different treatments was as F₂>F₁>F₀. Especially, the nutrient concentrations were significantly increased in 20-40 cm soil layer in layered application treatment (F₂). Compared with those in shallow application (F₁), the concentrations of nitrate nitrogen, ammonium nitrogen, available phosphorus, and available potassium increased by 16.03%, 7.67%, 8.82%, and 6.32% under F₂ under different irrigation frequencies from anthesis to maturity, respectively. Also, under F₂ treatments, the concentrations of both nitrate nitrogen and total nitrogen increased in 80-100 cm soil layer, and irrigation enhanced the treating effects. The distribution of available potassium concentration in 0-100 cm soil layer exhibited an S-shaped curve, and K concentration increased at maturity stage suggesting the phenomenon of potassium excretion. The wheat roots were mainly located in the 0-40 cm soil layer. Morphological & quantitative traits and physiological function of roots were significantly improved under F₂ in the 20-40 cm soil layer: compared with those under F₁, the root length density, root surface area density, root volume ratio, root dry weight density, root vigor, and root physiological potential were increased by 38.42%, 16.93%, 25.65%, 43.07%, 33.12%, and 31.10%, respectively. The correlation analysis showed that concentrations of available N, P, K nutrients in 0-20 cm soil layer were significantly positively correlated with root morphological & quantitative traits (P<0.01). Root physiological potential in 0-60 cm soil layer was significantly positively correlated with soil nitrate nitrogen, ammonium nitrogen, available phosphorus, and available potassium, respectively.【Conclusion】The layered N, P, K fertilization combined with key irrigations at three stages achieved a high degree of coordination between root configuration, growth, physiological functions, and appropriate distribution of available N, P, K nutrients, and enhanced the root biomass in 20-40 cm soil layer, indicating more absorptions of nitrogen, phosphorus, and potassium from the soil and a higher grain yield.