Scientia Agricultura Sinica

Research Progress on Seed Shattering of Rice

LÜ ShuWei, TANG Xuan, LI Chen

Scientia Agricultura Sinica. 2025, 58(1): 1-9. doi:10.3864/j.issn.0578-1752.2025.01.001

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

Genome-Wide Identification of Soybean LOX Gene Family and the Effect of GmLOX15A1 Gene Allele on 100-Seed Weight

WANG Wei, WU ChuanLei, HU XiaoYu, LI JiaJia, BAI PengYu, WANG GuoJi, MIAO Long, WANG XiaoBo

Scientia Agricultura Sinica. 2025, 58(1): 10-29. doi:10.3864/j.issn.0578-1752.2025.01.002

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

Comprehensive Evaluation for Soda Salinity and Alkalinity in Sorghum Seedling Stage and Selection of Indicators

QIAO ZhengYan, YU Miao, TANG YuJie, SHI GuiShan, LIU XinYu, LIU XiaoHan, WANG XinDing, LI Yang, WANG Nai, CHEN BingRu

Scientia Agricultura Sinica. 2025, 58(1): 30-42. doi:10.3864/j.issn.0578-1752.2025.01.003

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【Objective】This study was conducted to screen the concentration of soda saline-alkali stress solution and the determination index of saline-alkali tolerance, to establish the identification method of saline-alkali tolerance to large-scale identification of sorghum germplasms. The saline-alkali tolerance of the core germplasms of grain sorghum were comprehensively evaluated, and the saline-alkali tolerant germplasms were identified and selected to provide a germplasm basis for further breeding of saline-alkali tolerant parents and hybrids.【Method】The main components of saline-alkali soil of in The Songnen Plain are Na₂CO₃ and NaHCO₃. This experiment used 50 mmol·L^-1 NaHCO₃﹕Na₂CO₃=9﹕1 as a stress solution to simulate the moderate saline-alkali environment in Songnen Plain, the pH is 9.19, Salinity is 0.21%. Eight traits, including seedling height, root length, seedling fresh weight, root fresh weight, seeding dry weight, root dry weight, root-shoot ratio fresh weight and root-shoot ratio dry weight were used as measurement indexes and the saline-alkali tolerance characteristics of 285 sorghum core germplasms at seedling stage were identified. Principal component analysis was used to screen the salt-alkali tolerance identification indexes of grain sorghum at seedling stage and establish a mathematical model for salt-alkali tolerance evaluation at seedling stage. The saline-alkaline tolerance of 285 sorghum germplasms was classified by cluster analysis, and the germplasms with strong saline-alkaline tolerance were screened.【Result】50 mmol·L^-1saline-alkali stress showed inhibitory effects on 8 indexes of 285 sorghum germplasms, the average values of saline -alkali resistance coefficients are 0.794, 0.785, 0.565, 0.554, 0.802, 0.638, 0.978, and 0.841.Under saline alkali stress, 8 indexes showed significant positive correlations; the seedling height and root fresh weight could be used as the indexes for the identification and evaluation of soda saline-alkali stress in sorghum seedling stage by principal component analysis; The evaluation model of saline-alkali tolerance characteristics of sorghum seedlings was summarized by multiple linear regression analysis Y=0.097X4+0.171X2+0.201X6+0.157X1+0.105X3- 0.147, it can be used for comprehensive evaluation of multiple indicators. 285 grain sorghum core collections were divided into 5 grades by cluster analysis, strong saline-alkali tolerance, saline-alkali tolerance, intermediate type, sensitive type and extremely sensitive type, Among them, there were 8 strong salt-tolerant germplasms, 8 salt-tolerant germplasms, 112 intermediate germplasms, 134 sensitive germplasms and 23 extremely sensitive germplasms. The saline-alkali tolerant germplasm and extremely sensitive germplasm were planted in the moderate saline-alkali soil (pH 8.5-9.5, Salinity 0.3%) for verification in Zhenlai County of western Jilin Province. The average seedling emergence rate of strong saline-alkali tolerant germplasm was 45.4%, and the average seedling height was 23 cm. The average seedling emergence rate of salt-tolerant germplasm was 31.3%, and the average height was 20.9 cm. The average emergence rate of extremely sensitive germplasm was 20%, and the average seedling height was 12.3 cm.【Conclusion】8 strong soda saline-alkali tolerant germplasms and 8 saline-alkali tolerant germplasms were screened out from 285 sorghum germplasms resources with 50 mmol·L^-1 soda saline-alkali concentration (NaHCO₃﹕Na2CO₃=9﹕1). The seedling height and root fresh weight could be used as the preferred evaluation indexes for the identification of saline-alkali tolerance at seedling stage.

Effects of One-Off Irrigation and Nitrogen Fertilizer Management on Grain Yield and Quality in Dryland Wheat

WANG RongRong, XU NingLu, HUANG XiuLi, ZHAO KaiNan, HUANG Ming, WANG HeZheng, FU GuoZhan, WU JinZhi, LI YouJun

Scientia Agricultura Sinica. 2025, 58(1): 43-57. doi:10.3864/j.issn.0578-1752.2025.01.004

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【Objective】The objective of this study was to evaluate the effects of one-off irrigation and nitrogen (N) fertilizer management on grain yield and quality in dryland winter wheat (hereinafter referred to as wheat).【Method】From 2020 to 2022, the split-plot field experiment was conducted at the Mengjin, Yichuan and Luoning counties of Luoyang city in Henan province, China, in the typical dryland wheat production area at the intersection between Loess Plateau and Huang-Huai-Hai Plain. The two irrigation levels of no-irrigation during wheat growth period (I0) and soil-moisture-based one-off irrigation after regreening (I1, one-off supplemental irrigation was conducted to 85% of field capacity when the soil water content in the 0-40 cm soil layer after wheat regreening was lower than 60% of field capacity at the first time, there was only this irrigation during the whole growth stage) were assigned as the main plots; and the four N fertilizer managements of N0, N120, N180 and N240 were set as sub-plots, where N rates were 0, 120, 180 and 240 kg·hm^-2, respectively, and all of them were applied at sowing under I0 treatment, and 50% as basal, and 50% were applied along with the one-off irrigation under I1. The grain yield and protein yield, zinc content, protein and its components content, and main processing quality indicators of wheat were determined. 【Result】 Compared with I0, I1 significantly increased wheat grain yield and protein yield by 11.5%-73.0% and 9.1%-57.0%, respectively, in which the amplification enlarged with the increase of N rates, and that in the 2020-2021 was higher than that in the 2021-2022. However, I1 reduced the contents of zinc, and protein and its components in wheat grain, as well as the most indicators of processing quality compared with I0. Except for the globulin content at Yichuan in 2020-2021, compared with I0, I1 significantly decreased the content of zinc, protein and its components, and the processing quality of wheat grain. Among them, the content of zinc, albumin, globulin, gliadin, and glutenin were decreased by 5.0%-13.8%, 4.5%-14.1%, 6.4%-17.3%, 2.3%-24.8%, and 8.0%-13.9%, respectively, and the development time, stability time, wet gluten content, sedimentation value, extensibility, and maximum resistance were decreased by 5.3%-23.2%, 8.5%-51.1%, 2.0%-13.3%, 4.5%-18.1%, 4.6%-12.2% and 3.3%-10.6%, respectively. With the increase of N rate, wheat yield firstly increased and then decreased and wheat protein yield firstly increased and then stabilized under I0, while wheat yield firstly increased and then stabilized and wheat protein yield gradually increased under I1, however, the wheat quality indicators mostly tended to increase firstly and then stabilized under both I0 and I1. There were no significant differences between N240 and N180 for most quality indicators, but most of them were significantly higher than N120. The quality indicators of wheat grain under N120 were also significantly higher than that under N0. Considering the interaction effect, irrigation levels and N managements had significant interaction effects on yield and protein yield, but there was no interaction effect on most quality indicators. The grain yield under I1N180 did not change significantly but the protein yield was significantly decreased by 3.9%-4.9% compared with I1N240, however, both the grain yield and protein yield under I1N180 were significantly increased compared with other treatments. Although the content of protein and protein components and the processing quality in wheat grain under I1N180 were significantly lower than that under I0N180 and I0N240, these quality indicators were not significantly lower than that under I1N240. 【Conclusion】 The soil-moisture-based one-off irrigation after regreening combined with the N rate of 180 kg·hm^-2 and 50% N topdressing along with irrigation (I1N180) could synchronously improve the grain yield and stabilize the grain quality in dryland wheat. Therefore, I1N180 was suitable for wheat production in the dryland area, where one-off irrigation was guaranteed due to High-Standard Farmland Construction Program.

The Regional Distribution of Raw Cotton Quality in Xinjiang Based on Notarized Inspection Data for Cotton

LI PeiSong, LU YongDi, GUO Yu, ZHANG QiPeng, LIU TaoFen, WANG TianHe, YANG MingFeng, XIANG Dao, TIAN JingShan, ZHANG WangFeng

Scientia Agricultura Sinica. 2025, 58(1): 58-74. doi:10.3864/j.issn.0578-1752.2025.01.005

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【Objective】 Xinjiang cotton-growing area has the resource conditions for the formation of different cotton fibers quality types, due to its large spanning range, diverse climate and ecological types. It can provide theoretical bases for cotton-using enterprises to select multi-type, multi-grade and high-quality special cotton and optimize the cotton dominant production area, by studying the regional differences and distribution patterns and clarifying the climatic factors which affect the distribution of raw cotton quality in Xinjiang. 【Method】 Based on the quality certification inspection data of Chinese cotton from 2016 to 2020, the dataset encompassed fiber length, strength, Micronaire, and uniformity. The weighted average method was employed for analyzing the raw cotton quality across different cotton planting regions in Xinjiang. The linear trend slope method was utilized to determine the interannual variation trend of raw cotton quality in each individual county or city involved in cotton cultivation. Subsequently, a comprehensive evaluation of Xinjiang’s raw cotton quality was conducted based on the respective weights assigned to each index.【Result】The fiber length and strength of the northern region were significantly higher than those of the southern and eastern regions by 0.24-0.31 mm and 0.62-1.17 cN/tex. The quality of raw cotton in the Xinjiang Production and Construction Corps was noticeably superior to that of the Xinjiang Uygur Autonomous Region, and the fiber length and strength of raw cotton increased by 0.22 mm and 0.44 cN/tex, respectively. The fiber length ranging from 28.9 to 29.0 mm was predominantly concentrated in Huyanghe City of the Seventh Division (Chepaizi Reclamation Area), Shihezi City of the Eighth Division (Xiayedi Reclamation Area), and Beitun City of the Tenth Division (184 Corp) within the cotton producing region of northern Xinjiang. The strength in the northern region exhibited superior performance, with the strength between 28.4 and 29.9 cN/tex, while it was comparatively lower in the southern region. Micronaire A showed significant concentration in Wujiaqu City of the Sixth Division (Wujiaqu Reclamation Area), Beitun City of the Tenth Division (184 Corp), and Changji City within the cotton producing area of northern Xinjiang. The high-quality regions exhibited a consistent year-on-year growth trend, with fiber length increasing by 0.01-0.07 mm annually. The regions demonstrating this upward trend included Turfan Gaochang District in the eastern region of Xinjiang, Xinhe County, Magaiti County, Wensu County, Shache County, Shule County in the southern region of Xinjiang, and the Third Division of Tulushuk city (Xiaohaizi Reclamation Area). An average annual increase of fracture-specific strength ranging from 0.21 to 0.40 cN/tex primarily concentrated in Xinhe County, Wensu County and Tumushuk City of the Third Division (Xiaohaizi Reclamation Area) within the cotton-producing zone of Southern Xinjiang. Regions with better overall raw cotton quality were primarily concentrated in Manas County in Northern Xinjiang, Wujiaqu City in the Sixth Division (Wujiaqu Reclamation Area), Shihezi City in the Eighth Division (Xiayedi Reclamation Area, Anjihai Reclamation Area, Shihezi Reclamation Area, Mosuowan Reclamation Area), and Wensu County and Awati County in Southern Xinjiang, with fiber lengths ranging from 28.6 to 29.0 mm and strength from 28.4 to 29.9 cN/tex.【Conclusion】The quality of raw cotton in Xinjiang exhibited regional variations, which were influenced by the duration of days with temperatures over 35 ℃. Variety renewal and simplified cultivation were important ways to improve cotton quality and ensure the effective supply of high-quality raw cotton.

Integrating Transcriptomic and Metabolomic Analyses Reveals Maize Responses to Stalk Rot Caused by Fusarium proliferatum

CAO YanYong, CHENG ZeQiang, MA Juan, YANG WenBo, ZHU WeiHong, SUN XinYan, LI HuiMin, XIA LaiKun, DUAN CanXing

Scientia Agricultura Sinica. 2025, 58(1): 75-90. doi:10.3864/j.issn.0578-1752.2025.01.006

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【Objective】Stalk rot is a prevalent disease of maize (Zea mays) that severely affects maize yield and quality worldwide. The diseases are caused by several types of fungi and bacteria that are part of the complex of microorganisms. Among which, the ascomycete fungus Fusarium proliferatum has become one of the most aggressive causal agents of maize diseases in China in recent years. The study aims to provide a comprehensive analysis of multi-omics of maize stalks following F. proliferatum inoculation and valuable insights into the molecular basis of the response, including functional annotation and enrichment analyses of the major pathways enriched for differentially expressed genes (DEGs) and differentially expressed metabolites (DEMs) of maize conditioning F. proliferatum infection, and to lay theoretical foundation for maize breeding and disease management.【Method】Maize inbred lines ZC17 (ZhengC17, resistant) and CH72 (Chang72, susceptible), with different levels of resistance to F. proliferatum were used for sample collection. Seedlings at the nine-leaf stage with uniform performance were selected for artificial inoculation. Maize plants were inoculated by punching a hole in the stem at the second or third internode above the soil line using a sterile micropipette tip, followed by injection of 50 μL of freshly prepared F. proliferatum inoculum. A similar number of plants were inoculated with PDB as a mock treatment. The wounds were sealed with vaseline after inoculation. The upper and lower stem segments immediately adjacent to the inoculation segments were sampled at 7 dpi (days post inoculation), all individual samples were used for further transcriptome and nontargeted-metabolomics analysis. The inoculated internodes of the individual plants were split and symptoms were observed for evaluating of SRS_A (stalk rot score on average) and DSI (disease severity index). Multiple bioinformatics tools were used to conduct in-depth analysis of the transcriptome sequencing data and metabolomics data, and the DEGs were verified by real-time fluorescence quantitative PCR (RT-qPCR).【Result】Phenotypic and physiological characteristics indicated that the inoculated group of samples from the resistant inbred line ZC17 showed significantly lower lesion areas and symptoms than those of the sensitive inbred line CH72 after inoculation with F. proliferatum. The SRS_A and DSI of the ZC17 and CH72 stalks were consistent with the symptom phenotypes: the susceptible inbred CH72 had approximately 2.48-fold more SRSAs than the resistant inbred ZC17 line, and its DSI increased by 35.36% compared to that of ZC17. The results of the principal component analysis (PCA) showed a high reproducibility of the samples within the group. In PC1, ZC17 and CH72 were separated from each other. In PC2, FP group and MK group were separated from each other. The DEGs in the two comparison pairs (ZC17_FP vs. ZC17_MK, CH72_FP vs. CH72_MK) were analyzed. More DEGs were found in CH72 than those of ZC17 post inoculation, whereas nearly 50% of the DEGs share the same trend of expression between the two comparison pairs. Functional annotation and enrichment analysis found that DEGs and DEMs were enriched in pathways such as biosynthesis of plant secondary metabolites, phenylalanine metabolism, biosynthesis of plant hormones, and plant-pathogen interactions. Integrated analysis of transcriptomics and metabolomics data revealed that phenylalanine, tyrosine, and tryptophan biosynthesis and phenylalanine metabolism were significantly enriched in both the transcriptomic and metabolomic data for CH72 and ZC17. This result suggested that these pathways play a key role in the maize response to F. proliferatum. In addition, transcriptional factors of bHLH, MYB, NAC, and WRKY families were significantly activated after fungal inoculation, demonstrating the important role of transcription factors in the maize response to F. proliferatum infestation. To further confirm the reliability of the sequencing data, 11 genes were randomly selected for qPCR validation, which showed that the trends of the RNA-Seq and qPCR results were consistent in both CH72 and ZC17, Spearman rank correlation analysis also showed high concordance between the RNA-Seq and qPCR results (r=0.75, P=7.5e-05).【Conclusion】Phenylalanine metabolism-related pathways are crucial in maize response to F. proliferatum stalk rot. Key enzymes such as C4H, PAL, ADT, GOT and significantly up-regulated metabolites such as 2-coumaric acid, 3-hydroxycinnamic acid, indole, phenylalanine, tryptophan and tyrosine play an important role in plant disease resistance. The potential disease resistance-related transcription factors, genes and metabolites excavated in this study can provide an important basis for further analysis of the molecular response mechanism of maize to F. proliferatum stalk rot.

Analysis on Distribution and Change of Weed Community in Winter Wheat Field in Henan Province

GAO XingXiang, KONG Yuan, ZHANG YaoZhong, LI Mei, LI Jian, JIN Yan, ZHANG GuoFu, LIU ShuaiShuai, LIU MingPing, ZENG Yan, BAI LianYang

Scientia Agricultura Sinica. 2025, 58(1): 91-100. doi:10.3864/j.issn.0578-1752.2025.01.007

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【Objective】In the past 10 years, the weed communities in the winter wheat fields in Henan Province have changed significantly. The objective of this study is to clarify the succession of weed communities in the six major planting areas in Henan Province, analyze the reasons of weed succession, and to provide a theoretical basis for the establishment of accurate control strategy of weeds in winter wheat fields.【Method】A total of 378 plots in 17 cities of Henan Province were sampled from November to December in the 2023 to investigate the weed species and weed number in winter wheat fields, compared with the results of 2013, the weed community composition in six major planting areas of winter wheat fields in Henan Province was determined, and the weed community change law was analyzed.【Result】The characteristics of weed communities in winter wheat fields in Henan Province were: (1) Gramineous weeds developed rapidly, Aegilops tauschii, Lolium multiflorum, Bromus japonicas, and Alopecurus myosuroides gradually spread from the local area to the whole province, almost covering the whole province major planting areas at present. Among them, A. tauschii and B. japonicus mainly occurred in dry-stubble wheat fields. In 2013, 14th, 15th, 27th and 35th relative abundances of the four weeds were ranked, respectively, but relative abundances ranked 2nd, 5th, 8th and 15th, respectively, in 2023. (2) Galium aparine and Veronica persica had always been the dominant broad-leaved weeds in winter wheat fields in Henan Province, with relative abundance of 26.89% and 10.68% in 2023, respectively. In the past 10 years, two surveys showed that the comprehensive relative abundance of G. aparine ranked first, G. aparine caused great damage in both dry-stubble wheat field and rice-stubble wheat field, and V. persica had risen from 6th to 3rd. (3) G. aparine, A. tauschii, V. persica, and Descurainia sophia became the dominant weeds in winter wheat fields in Henan Province. In 2013, only G. aparine and Capsella bursa-pastoris had relative abundance of more than 10%, which was 17.38% and 10.92%, respectively, but in 2023, the relative abundance of G. aparine, A. tauschii, V. persica, and D. sophia exceeded 10%, which was 26.89%, 13.45%, 10.68%, and 10.65%, respectively. (4) The damage of regional dominant weeds was also serious, such as Lamium amplexicaule, Raphanus raphanistrum, Malachium aquaticum, Euphorbia helioscopia, Lithospermum arvense, and Geranium carolinianum. In addition, regional harmful weeds such as Lapsana apogonoides, Mazus japonicus, and Alopecurus aequalis were mainly distributed in rice-stubble wheat fields.【Conclusion】The changes of the weed communities in winter wheat fields in Henan Province are mainly caused by the changes of farming systems, the spread and invasion of malignant weeds and the development of weed resistance. Cross-regional operation of combine harvester and human unconscious carrying and spreading are also important factors to promote the change of weed community. Therefore, in the prevention and control of weeds in winter wheat fields in Henan Province, the integrated weed control strategies, such as combining chemical herbicides with agronomic measures, the precise selection of herbicides according to the field grass phase in different planting areas and using herbicides with different mechanisms, should be promoted.

The Interactive Effects of Organic Fertilizer Substituting Chemical Fertilizers and Arbuscular Mycorrhizal Fungi on Soil Nitrous Oxide Emission in Shajiang Black Soil and Fluvo-Aquic Soil

DU JiaQi, ZHANG ZiWei, WANG RuoFei, LI Xing, GUO HongYan, YANG Shuo, FENG Cheng, HE TangQing, Giri Bhoopander, ZHANG XueLin

Scientia Agricultura Sinica. 2025, 58(1): 101-116. doi:10.3864/j.issn.0578-1752.2025.01.008

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【Background】Organic fertilizer substitution (OF) is an effective chemical fertilizer reduction strategy, which can change the ratio of soil organic carbon to inorganic nitrogen (N), so as to regulate nitrous oxide (N₂O) emission. Similarly, arbuscular mycorrhizal fungi (AMF) forms a symbiotic strategy with most terrestrial plants, increases plant soil nutrient uptake, and affects soil N₂O emission. However, the interactive effects of both OF and AMF on soil N₂O emissions are poorly understood, especially in different agricultural soil environments, and the mechanism of their interaction is also unclear. 【Objective】 This study aimed to explore the mechanical effects of both OF and AMF on soil N₂O emissions during maize growth periods in different soil types, so as to provide the appropriate methods to reduce chemical fertilizer application for farmland management.【Method】Taking Shajiang black soil (SJ) and Fluvo-aquic soils (CT) as research object, a two factor experiment with organic fertilizers replacing chemical fertilizers (0%OF: only chemical N fertilizer; 25%OF: equal N organic fertilizer replacing 25% chemical N fertilizer; 50%OF: equal N organic fertilizer replacing 50% chemical N fertilizer) and AMF (M+, inoculation of arbuscular mycorrhizal fungi; M-, no inoculation of arbuscular mycorrhizal fungi) was carried out in 2020, with a non-fertilization control (CK). The maize biomass, N accumulation, grain yield, soil inorganic N, and soil N₂O emission flux were measured during maize growth period in both the soil types, and a relative abundance of denitrification functional genes, such as nirK and nirS, was investigated too. 【Result】There was no significant difference in maize grain yield among different OF treatments under the conditions of Shajiang black soil, while grain yield showed decreasing tendency with the OFS ratio increasing in Fluvo-aquic soils. Compared with 0%OF treatment, the cumulative N₂O emissions under 25%OF and 50%OF treatments in Shajiang black soil reduced by 17.6% and 18%, respectively, and by 13.5% and 3.9% in the Fluvo-aquic soil. Compared with non-AMF (M-treatment), the presence of AMF (M+ treatment) increased maize grain nitrate reductase, nitrite reductase, glutamine synthase, glutamate synthase, and maize grain yield, while reduced soil N₂O emissions. The reduction of cumulative N₂O emissions in Shajiang black soil was by 26.5%-28.2%, and by 2.7%-13.5% in Fluvo-aquic soil; the reduction in case of 25% OFM+ treatment was 34.6% and 22.5% in Shajiang black soil and Fluvo-aquic soils respectively, while the root total length, root surface area, root volume and root diameter per plant increased significantly. Correlation analysis showed that N₂O emissions were positively related with soil NH₄⁺and NO₃^- under both Shajiang black soil and Fluvo-aquic soil conditions, while negatively related with AMF infection rate in both Shajiang black and Fluvo-aquic soils; whereas, the emissions were positively related with the copy numbers of nirK and nirS genes under Shajiang black soil conditions.【Conclusion】The replacing chemical fertilizers with organic fertilizers and inoculation with AMF could reduce N₂O emissions under different soil types. This interactive effect might be the result of expanding root N absorption area through AMF colonization, and by regulating the expression of key functional microorganisms in soil denitrification. Therefore, the study recommends replacement of 25% chemical fertilizer (OF25%) with organic fertilizers and inoculation with AMF could be an ideal fertilizer management method to maintain maize production stable and reduce chemical fertilizer application rate and greenhouse gas emissions.

Litter Decomposition Characteristics of Steppe Ecosystems with Different Precipitation Gradients

LI AoGui, CHEN YaRu, PENG ZiYang, RU JingYi, LIU WeiXing

Scientia Agricultura Sinica. 2025, 58(1): 117-126. doi:10.3864/j.issn.0578-1752.2025.01.009

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【Objective】 This study aimed to explore the dynamics of litter decomposition under different environmental precipitation conditions, thereby facilitating understanding of the carbon (C) and nutrient cycling processes and ecosystem functions of steppe ecosystems. 【Method】In this study, soil monoliths selected from three types of temperate steppe along the natural precipitation gradient (i.e. desert, typical, and meadow steppes), and transplanted to conduct a two-year litter decomposition experiment of Cleistogenes squarrosa in typical steppe. We continuously monitored mass loss, the remaining rates of nitrogen (N) and phosphorus (P), as well as the activities of β-glucosidase (BG), leucine aminopeptidase (LAP), N-acetylglucosidase (NAG) and acid phosphatase (AP) during decomposition, to discover the influence of long-term historical precipitation on litter decomposition rate and the dynamic characteristics of decomposition process. 【Result】The litter decomposition rate was highest in the typical steppe with a decomposition constant (k value) of (0.32±0.01) a^-1, were no difference observed between the desert steppe and the meadow steppe. The remaining rate of N and P in litters after two years of decomposition were lowest in typical steppe, with values of (53.0±2.4) % and (58.6±3.9) %, respectively. The N element mainly showed a mineralization pattern during the decomposition stages, while the P was fixed from environment in early stages whereas mineralized in late stages, and microbial P accumulation in litters was greatest in desert steppe. The activities of all enzymes showed fluctuations depending on decomposition stages. Over the whole decomposition time, the activities of C-acquiring enzyme (BG) and N-acquiring enzyme (LAP and NAG) were highest in typical steppe, while the activities of P-acquiring enzyme (AP) were highest in meadow steppe. Combined with the results of enzyme stoichiometry, litter decomposition showed C-limitation in typical steppe, while it was P-limited in meadow steppe. The litter mass loss rate increased with the enhancement of litter BG and NAG activities across the three steppes. 【Conclusion】The mass loss rate, nutrient release rate and enzyme activities of steppe litter did not increase with the increase of precipitation gradient. The litter decomposition fixed more P from environment in water-limited steppe ecosystems. This study reveals the characteristics of litter decomposition process in response to different historical precipitation, advancing our understanding of plant-soil-microbe C and nutrient cycles.

Variation Characteristics and Key Influencing Factors of Near-Surface Ambient Ammonia Concentration in Typical Cropland Areas in Henan Province

LÜ JinLing, YOU Ke, WANG XiaoFei, XIAO Qiang, LI WenFeng, MA Jin, YANG Qing, ZHANG JinPing, KONG HaiJiang, CHANG YunHua

Scientia Agricultura Sinica. 2025, 58(1): 127-140. doi:10.3864/j.issn.0578-1752.2025.01.010

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【Objective】 Ammonia volatilization from cropland is one of the main sources of ammonium salts in atmospheric particulate matter, which has a close impact on urban and rural air quality. The temporal-spatial variation characteristics of near-surface atmospheric ammonia concentration and key influencing factors in a typical agricultural area of Henan Province was conducted systematically, so as to provide the scientific basis for targeted management of atmospheric particulate pollutants in cropland areas.【Method】10 typical cropland areas (wheat-maize rotation areas) in Henan Province were selected to conduct a two-year study on monitoring near-surface ammonia concentration by using the ammonia passive method and investigating its driving factors. 【Result】 In terms of time (seasonality), the highest average near-surface ammonia concentration value was found in summer, with an average of 12.0 μg N·m^-3, followed by spring and autumn, with an average of 10.8 and 8.9 μg N·m^-3, respectively, and the lowest value in winter, with an average of only 6.7 μg N·m^-3. From a spatial perspective, the highest ammonia concentration in the cropland area of Zhengzhou in east Henan was 14.7 μg N·m^-3 on average, followed by Xinxiang and Anyang in north Henan with annual average atmospheric ammonia concentrations of 12.5 and 11.0 μg N·m^-3, respectively. Zhengzhou in central Henan and Jiaozuo in north Henan had near-surface atmospheric ammonia concentrations of 10.9 and 10.6 μg N·m^-3, respectively, while the near-surface atmospheric ammonia concentrations in Luoyang, Pingdingshan, Xuchang, Luohe and Zhoukou in west Henan and south Henan were between 7.9 and 9.6 μg N·m^-3. From the perspective of soil types, among which fluvo-aquic soils had the highest near-surface ammonia concentration, with values ranging from 11.0 to 14.7 μg N·m^-3; the ammonia concentration values in the cinnamon soil and yellow cinnamon soil areas ranged from 9.0 to 9.6 μg N·m^-3; the ammonia concentration in lime concretion lime concretion black soil and yellow brown soil cropland was relatively low, with values ranging from 8.06 to 8.11 μg N·m^-3. The high and low near-surface ammonia concentrations in different regions were the result of multiple factors working together. Among them, there was a significant positive correlation between nitrogen fertilizer application rate and soil pH value and near-surface ammonia concentration, while there was a significant negative correlation between rainfall and near-surface ammonia concentration.【Conclusion】Based on the above research results, it was believed that reducing nitrogen application rate could help to systematically reduce the near-surface ammonia concentration in the cropland area of Henan Province, and the cropland area of northern and eastern Henan Province were the key areas of attention.

Aroma Quality Analysis of Guangdongxiangshui Lemon Based on Molecular Sensory Technology

ZHANG SiNing, ZHANG XingRui, WU DongXuan, KANG JingBo, CHEN XiaoLin, GENG LiJun, YIN GuangMin, CHEN JiaJing, GAO JunYan, CAI ZhongHu, LIU Yuan, XU Juan

Scientia Agricultura Sinica. 2025, 58(1): 141-155. doi:10.3864/j.issn.0578-1752.2025.01.011

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【Objective】Tea drinks made from Guangdongxiangshui lemon is popular among consumers, but its aroma profile, main aroma-active compounds and corresponding key biosynthesis genes still need to be analyzed. In this study, integrated molecular sensory technology including metabolomics and sensory evaluation was used to explore the material basis and corresponding key genes for the aroma quality of Guangdongxiangshui lemon, aiming at laying a foundation of the citrus aroma quality. 【Method】The volatiles of Guangdongxiangshui lemon from three areas, including Weishan, Yunfu and Wuzhou, were detected via GC-MS, and the aroma quality were evaluated by sensory evaluation panels. The aroma active compounds of Guangdongxiangshui lemon were identified by GC/O-MS combined with aroma extract dilution analysis (AEDA), aroma activity value (OAV) analysis and aroma recombination experiment, and then the characteristic aroma compounds were further identified. Based on gene family analysis, the genes related to aroma formation were illustrated. 【Result】A total of 40, 21 and 33 volatiles were identified in the flavedo, pulp and slices of Guangdongxiangshui lemon, respectively. The samples with the highest volatile content in flavedo and pulp tissues were from Weishan and Yunfu, respectively. In terms of aroma attributes, the aroma intensity of Guangdongxiangshui lemon slices from Weishan and Yunfu was significantly higher than that of Wuzhou. The whole fruit aroma quality of samples from Wuzhou was better than that of samples from other origins. Solvent-assisted flavor evaporation (SAFE) and other methods were used to extract the essential oil of Guangdongxiangshui lemon in Weishan, and 25 aroma active compounds were identified. Combined with OAV analysis and aroma recombination experiments, citronellal and citral were further identified as its characteristic aroma compounds, and the aroma flavor wheel was further constructed. Based on the conserved domain and Blast comparison, 52 terpene synthase (TPS) genes were identified in Guangdongxiangshui lemon genome, which might be involved in the aroma compounds synthesis. 【Conclusion】The volatile spectrum and sensory evaluation showed that the aroma quality of Guangdongxiangshui lemon slices from Weishan were outstanding. A total of 25 aroma active compounds were identified. Among them, citronellal and citral were the characteristic aroma compounds of Guangdongxiangshui lemon, while d-limonene provided a background aroma. Combined with quantitative descriptive analysis and odor note collected via GC/O-MS, the aroma wheel of Guangdongxiangshui lemon was constructed with 15 aroma descriptors in 6 categories, including ‘fruity’ ‘woody’ ‘medicinal’ ‘spicy’ ‘floral’ and ‘grassy’. Furthermore, 52 TPS genes were mined in Guangdongxiangshui lemon genome, which might participate in the aroma compounds synthesis.

Cloning and Functional Analysis of the Autophagy Gene ATG8f in the Grapevine

GE Yi, ZHENG QiuLing, CHEN MengXia, XIA JiaXin, FANG Xiang, TANG MeiLing, FANG JingGui, SHANGGUAN LingFei

Scientia Agricultura Sinica. 2025, 58(1): 156-169. doi:10.3864/j.issn.0578-1752.2025.01.012

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【Objective】This study aims to investigate the role of the grape autophagy gene ATG8f in regulating copper stress tolerance in plants, thereby laying the foundation for elucidating copper tolerance mechanisms and constructing regulatory networks. 【Method】Based on multi-omics sequencing analysis of Shine Muscat grapevine under copper stress, the autophagy gene VlATG8f was identified and its sequence characteristics were analyzed. The CDS sequence of VlATG8f was cloned and an overexpression vector was constructed. The subcellular localization of the VlATG8f protein was studied through transient expression in tobacco. Heterologous expression of VlATG8f in Arabidopsis was achieved using the floral dip method. Seed germination rate and root length were measured to compare the growth and development of wild-type and transgenic lines under copper stress. Real-time quantitative PCR was used to analyze the expression levels of related antioxidant genes, and yeast two-hybrid and bimolecular fluorescence complementation (BiFC) assays were used to preliminarily screen for VlATG8f- interacting proteins. 【Result】The CDS of VlATG8f was 393 bp, encoding 130 amino acids. Bioinformatics analysis revealed that the ATG8f protein sequences in Arabidopsis, tomato, apple, pear, peach, and grapevine were relatively conserved, all containing a Ubl_ATG8 conserved domain, indicating potential functional were conserved. Subcellular localization showed that the VlATG8f protein was located on both the nucleus and cell membrane. Under normal conditions, both wild-type and VlATG8f-overexpressing lines exhibited healthy growth with green leaves. Under copper stress, the transgenic lines were less stunted and exhibited milder symptoms of chlorosis, leaf curling, reduced root hair size, and increased lateral roots compared to wild-type plants. Overexpression of VlATG8f in Arabidopsis resulted in less growth inhibition under copper stress, higher seed germination rate, longer root, and lower accumulation of hydrogen peroxide (H₂O₂), indicating enhanced copper tolerance. Additionally, the expression of antioxidant genes AtCSD1 and AtCCS1 increased in VlATG8f-overexpressing plants under copper stress, while the expression of the key ROS synthesis gene RbohB decreased, promoting ROS scavenging. Yeast two-hybrid screening identified 23 potential interacting proteins with VlATG8f. BiFC further confirmed strong interactions between VlATG8f and proteins such as PYL8, MnSOD, AUX22D, bZIP17, and COT44. 【Conclusion】Overexpression of VlATG8f may enhance copper tolerance in transgenic lines by strengthening the antioxidant system, reducing ROS synthesis, and promoting the synthesis of plant hormones, thereby mitigating copper toxicity in plants.

Effects of Alcalase Hydrolysis on the Structure, Aggregation Behavior and Gelling Properties of Quinoa Protein Isolate

FENG Xiao, WEI JianFeng, FU LiXiao, WU ChaoSheng, YANG YuLing, TANG XiaoZhi

Scientia Agricultura Sinica. 2025, 58(1): 170-181. doi:10.3864/j.issn.0578-1752.2025.01.013

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【Objective】This research studied the effects of alcalase hydrolysis on the structure, physicochemical properties and aggregation behavior of quinoa protein isolate (QPI), and explored its effects on the gelling properties of QPI. 【Method】QPI was extracted by alkaline extraction and acid precipitation method at 4 ℃. Alcalase with different enzyme-substrate ratios was added to the QPI solution to hydrolyze the protein. Thereafter, the changes of the composition, particle size, Zeta potential, solubility, and surface hydrophobicity (S₀-ANS) of QPI were analyzed, and the correlation between these changes and the Th T fluorescence intensity and morphology of protein thermal aggregates were discussed. Furthermore, the concentration of QPI dispersion was elevated to form heat-induced QPI gels. The correlation among alcalase hydrolysis, aggregation behavior and gelling properties of QPI was discussed through the analysis of the microstructure, texture and protein secondary structure of QPI gels. Meanwhile, the reasons for the changes in the gelling properties of QPI induced by alcalase hydrolysis were revealed.【Result】With the increase of enzyme substrate ratio (E/S), the protein particle size of QPI dispersion (2%, w/v) gradually decreased, and its electronegativity increased first and then decreased. Meanwhile, the surface hydrophobicity of QPI gradually increased as the E/S increased. At the same time, the Th T fluorescence intensity of QPI aggregates showed an upward trend as E/S rose from 0 to 0.08%, and then declined when the E/S further increased to 0.14%. Through TEM observation, short fibrils (145-306 nm) and long fibrils (217-406 nm) were formed when E/S was 0.05% and 0.08%, respectively. However, with the further increase of E/S ratio, the length of fibrils became shorter, and more amorphous aggregates appeared. In addition, it was found that the aggregation behavior of QPI had a significant effect on its gelling properties (P<0.05). QPI gels showed enhanced hardness, higher storage modulus and a denser network structure, when fibrillar aggregation was dominant. Compared with short fibrils, long fibrils exerted a more significant effect to improve the gelling properties. Furthermore, alcalase showed a significant effect on the protein secondary structure of QPI gels, and the contents of β-sheet and random coil rose first and then decreased with the increase of E/S.【Conclusion】The limited alcalase hydrolysis promoted QPI to form ordered fibrillar aggregates, and further improved its gelling properties. When the E/S was 0.08%, QPI formed the longest fibrils, and QPI gels exhibited the highest hardness as well as the most favorable viscoelastic properties. Meanwhile, the protein secondary structure of QPI gels was ordered, and their microstructure was dense. However, the higher degree of hydrolysis was unfavorable to form fibrillar aggregates and failed to improve the gelling properties. Therefore, limited alcalase hydrolysis could significantly improve the weak gelling properties of QPI through fibrillation.

Immune Effect Evaluation of Combined Inactivated Vaccine Against Avian Influenza and Newcastle Disease

YU QingQing, ZHOU XiangYu, LI WenXin, LIU YanJing, WANG Yan, HE XinWen, HE Chen, DENG GuoHua, SHI JianZhong, TIAN GuoBin, BAO HongMei, ZENG XianYing, CHEN HuaLan

Scientia Agricultura Sinica. 2025, 58(1): 182-191. doi:10.3864/j.issn.0578-1752.2025.01.014

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【Background】 H5, H7 and H9 subtypes of avian influenza viruses (AIV) and Newcastle disease virus (NDV) are important pathogens that seriously jeopardize the avian industry, and vaccination with inactivated vaccines in the form of oil emulsions is the mainstay of prevention of avian influenza and Newcastle disease. At present, more than two vaccines are needed to prevent these infectious diseases in poultry farms, which leads to more times of vaccination and heavy immune burden on poultry. In addition, the mineral oil used to produce oil-emulsion inactivated vaccines is mainly dependent on imports, which has the risk of “neck sticking”. 【Objective】In order to reduce the number of vaccinations, lower the burden of immunization, and compare the effects of domestic and imported mineral oil adjuvants, this study developed and evaluated the inactivated vaccines, which could simultaneously prevent avian influenza (H5+H7+H9) and Newcastle disease by using different mineral oil adjuvants. This study expected to achieve the immunization effect of “one immunization preventing multiple diseases” and provide data support for the localization of mineral adjuvants for animal vaccines.【Method】A total of five vaccine strains of avian influenza H5-Re13, H5-Re14, H7-Re4, H9-GX11583 and Newcastle disease ND rLa-VII strains that have been constructed in the laboratory, which were inoculated into chicken embryos, harvested the allantoic fluid, concentrated and inactivated. Different mineral oil adjuvants (Total, Marcol 52 and HTM70) were added at a ratio of 1 part antigen to 3 parts of adjuvant. The mixture was then thoroughly mixed and emulsified to prepare the combined inactivated vaccine. Finally, the safety and efficacy of the vaccine were evaluated through intramuscular injection on three-week-old SPF chickens using doses of 2 mL and 0.5 mL, respectively.【Result】The results of the immunity efficacy test showed that the three kinds of mineral oil adjuvanted dichotomous multivalent inactivated vaccines had good safety for chickens; all three mineral oil adjuvanted vaccines could produce effective HI antibodies against H5-Re13, H5-Re14, H7-Re4, H9-GX11583 and ND rLa-VII strains after inoculation of chickens, and could obtain complete immune protection against the attack of the efficacy test strains. The results of HI antibody duration showed that all three mineral oil adjuvant inactivated vaccines could continuously induce high level of antibodies for more than half a year, compared with imported mineral oils (Total, Marcol 52), the level of HI antibody induced by domestic mineral oil HTM70 was close to that of imported mineral oil Total and higher than that of imported mineral oil Marcol 52, but the domestic mineral oil adjuvant HTM70 had no significant difference between batches.【Conclusion】The combined inactivated vaccine against avian influenza (H5+H7+H9) and Newcastle disease prepared in this study had a good immune efficacy on SPF chickens, and the domestic substitution of mineral oil adjuvant was expected.

Prevalence and Transmission of Salmonella Among Different Broiler Breeding Processes in Beijing-Tianjin-Hebei Region

LIU FangQin, CUI MingQuan, ZHANG Lu, CHEN Yu, WANG HeJia, ZHANG ChunPing

Scientia Agricultura Sinica. 2025, 58(1): 192-202. doi:10.3864/j.issn.0578-1752.2025.01.015

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【Background】Salmonella is an important zoonotic pathogen and foodborne pathogen, with over 2 600 identified so far. Different serotypes of Salmonella exhibits varying degrees of pathogenicity to animals and humans. Broiler is one of the important hosts of Salmonella epidemic transmission, and its contamination status is directly related to the healthy breeding of broilers and public health security. The broiler production chain is the main source of Salmonella infection in broilers, which mainly covers breeder farms, broiler hatcheries, and broiler farms, etc. The study of the prevalence and transmission of Salmonella in different production links of broilers is of great significance for the prevention and control of Salmonella in broilers and for public health and safety. It is important to study the prevalence and transmission of Salmonella in different links of broiler production for the prevention and control of Salmonella in broiler and public health safety.【Objective】 This study systematically investigated the prevalence, serotype distribution and molecular typing of Salmonella in different production chains of broilers, taking broiler breeder farms, broiler hatcheries and commercial broiler farms in the Beijing-Tianjin-Hebei region as an entry point, which provided data for the study of Salmonella epidemic and transmission in broiler production chain.【Method】A total of 2 572 samples were collected from 28 broiler farms in different production stages of broilers in the Beijing-Tianjin-Hebei region (including within a certain breeding group), of which 324, 747 and 1 501 samples were collected from broiler breeder farms, broiler hatcheries and commercial broiler farms, respectively. Firstly, the samples were cultured for the enrichment of Salmonella, and then the isolation and identification of Salmonella were carried out by color development medium and Polymerase Chain Reaction (PCR); secondly, the identified Salmonella were serotyped by Danish serum, and the identification of Salmonella was carried out by Pulsed Field Gel Electrophoresis (PFG), and the identification of Salmonella was carried out by PFG, and the identification of Salmonella was carried out by PFG. The results were analyzed by Pulsed Field Gel Electrophoresis (PFGE) method for molecular typing of Salmonella. Finally, the carrier status, serotype distribution and molecular typing results of broilers from different production farms were analyzed and compared.【Result】A total of 335 strains of Salmonella were isolated from different production segments of broilers, with an overall isolation rate of 13.0%, of which the isolation rates of Salmonella from broiler breeder farms, broiler hatcheries and commercial broiler farms were 3.4%, 30.3% and 6.5% respectively. A total of 32 Salmonella strains were isolated from different production segments within the same farming group, with an isolation rate of 8.6%, among which the isolation rates of Salmonella from broiler breeder farms, broiler hatcheries and commercial broiler farms were 2.0%, 14.0% and 9.2%, respectively. A total of 11 serotypes of Salmonella isolates were distributed, with the dominant serotype was S. enteritidis, followed by S. tennessee, S. gallinarum and S. javiana. There were differences in the dominant serovars of Salmonella in different production stages of broiler chickens, including S. enteritidis and S. nitra in broiler breeder farms; S. enteritidis, S. tennessee, and S. gallinarum in broiler hatcheries; and S. enteritidis, S. javiana, and S. gallinarum in commercial broiler farms. Except for five strains of S. eschweiler isolated from feed, all Salmonella serotypes isolated from different production segments within the same farming group were S. enteritidis. The PFGE typing results of Salmonella isolates from different production segments of broiler chickens showed that the PFGE homology of Salmonella from different serotypes was low; the PFGE band spectra of most S. enteritidis belonged to clustering group I, with a degree of similarity of 93.1%; and there were identical PFGE spectra of S. enteritidis isolated from different production segments in the same breeding group.【Conclusion】The isolation rate of Salmonella in various production segments of broiler in Beijing-Tianjin-Hebei region varies greatly, mainly dominated by the epidemic transmission of S. enteritidis, and there is vertical clonal transmission of S. enteritidis between different production links of broilers; breeders are an important source of Salmonella infection in broilers, the environment of the farms and feeds are also one of the sources of Salmonella infections in broilers.Therefore, it is necessary to strengthen the purification of Salmonella in breeder chickens, and at the same time to do a good job in the prevention and control of Salmonella in other production links, in order to guarantee the healthy breeding of broiler chickens and the security of public hygiene.

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