Scientia Agricultura Sinica

Analysis of the Breeding Utilization Effects of Loci Related to Wheat Flour Color

ZHAI ShengNan, LÜ YingYing, HE ZhongHu, XIA XianChun, MA RuiFeng, WANG Ying, LI FaJi, CAO XinYou, LI HaoSheng, HAN Ran, WANG XiaoLu, LI JiHu, LIU JianJun

Scientia Agricultura Sinica. 2026, 59(10): 2061-2074. doi:10.3864/j.issn.0578-1752.2026.10.001

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【Objective】The flour color is a crucial index for evaluating wheat quality. Identifying superior allelic variations at loci associated with flour color and clarifying their breeding utilization effects will provide a foundation for molecular marker-assisted breeding of wheat flour color.【Method】Using functional markers, molecular detection was conducted on 12 flour color-related loci in 166 wheat varieties (lines), including the Psy-A1, Pds-B1, Lcye-A1, Lcye-B1, Lox-B1, Ppo-A1, Ppo-B1, Ppo-D1, Pod-A1, Pod-D1, Pod-2D genes, and the 1B/1R translocation. Combined with the phenotypic measurements of flour color parameters (Yellow pigment content (YPC), L* value, a* value, b* value and whiteness), the influence of different allelic variations on flour color were analyzed to comprehensively and systematically evaluate the breeding utilization effects of each locus.【Result】The flour color of the tested materials exhibited a wide variation range. The average value of YPC was 1.18 μg·g^-1, with a range of 0.57-2.96 μg·g^-1; The average value of L* was 90.29, ranging from 87.12 to 92.16; the average a* value was -0.86, varying between -1.78 and -0.09; the average b* value was 8.83, with a range of 5.21-14.69; and the average whiteness was 86.78, spanning from 81.35 to 90.30. Environment, genotype, and the interaction between genotype and environment all significantly influenced flour color, with genotype exerting the strongest effect on the phenotypic variations. Psy-A1 and 1B/1R translocation significantly affected YPC, L* value, a* value, b* value and whiteness; Lcye-B1 significantly influenced YPC, a* value, b* value and whiteness; Pds-B1 and Lox-B1 significantly impacted L* value, b* value and whiteness; Pod-2D significantly influenced L* value and whiteness; Lcye-A1 significantly affected L* value; Ppo-A1 and Ppo-D1 significantly influenced a* value. These nine loci had substantial impacts on flour color and exhibited great potential for breeding applications. Wheat varieties (lines) containing Psy-A1b, Pds-B1b, Lcye-A1b, Lcye-B1b, Lox-B1a, Ppo-A1b, Ppo-D1a, Pod-2D-GG, Pod-2D-AG and non-1B/1R translocation exhibited high brightness and whiteness flour color. These genotypes were designated as superior alleles, with distribution frequencies of 34.94%, 20.48%, 97.59%, 66.27%, 26.38%, 50.91%, 57.23%, 48.80%, 15.06% and 51.20%, respectively. As the number of superior alleles increased, the L* value, a* value and whiteness gradually increased, while YPC and b* value gradually decreased. The materials pyramiding 7-8 superior genes exhibited the optimal flour color. There were significant differences in flour color and the allelic variation frequencies of related genes among wheat varieties (lines) from different regions. A total of 22 varieties, such as Zhengyin1, Zimai12 and Wanmai19, carried more than seven superior alleles and could be used as parental materials for breeding wheat varieties with high brightness and whiteness flour.【Conclusion】Psy-A1, Pds-B1, Lcye-A1, Lcye-B1, Lox-B1, Ppo-A1, Ppo-D1, Pod-2D and 1B/1R translocation significantly influence flour color and exhibit strong breeding practicability. Twenty-two wheat varieties, such as Zhengyin1, Zimai12 and Wanmai19, can be used as excellent parents for flour color improvement.

QTL Mapping and Genomic Selection of Stay-Green in Soybean (Glycine max L.)

LIU ZhiYu, CHEN YiJie, YU Huan, SHEN MaoTing, QIU LiJuan, WANG Jun

Scientia Agricultura Sinica. 2026, 59(10): 2075-2087. doi:10.3864/j.issn.0578-1752.2026.10.002

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【Objective】The “stay-green” trait can prolong the effective photosynthesis duration in soybeans and increase dry matter accumulation, thereby holding significant potential for improving yield. Mining stay-green related QTL and elucidating their molecular mechanisms can provide a theoretical basis and technical support for enhancing soybean yield.【Method】A soybean nested association mapping population was evaluated for stay-green traits across multiple environments. Genome-wide association study was conducted using genotyping data. Candidate genes were screened via SNP variation, tissue-specific expression, and functional annotation analyses, haplotype, promoter cis-acting elements, and protein structure prediction analyses were performed to characterize the candidate genes. Additionally, the application effect of genomic selection for the stay-green trait was evaluated.【Result】Six significant QTL intervals were co-localized on chromosomes 3, 4, 5, and 16. Among these, qSG5-1 (Chr.5: 41600128..42273303, 613.18 kb) was repeatedly mapped across multiple environments and represents a novel QTL for stay-green regulation in soybean. Linkage disequilibrium analysis allocated two significantly associated regions within qSG5-1: qSG5-1.1 (Chr.5: 41798499..41996276, 197.78 kb) and qSG5-1.2 (Chr.5: 41996989..42273303, 276.32 kb), containing 29 and 37 genes, respectively. SNP variation analysis identified 53 genes containing variants that cause nonsynonymous mutations, alternative splicing, stopgain, or stoploss. Of these, eight genes were transcriptionally active in stems and leaves. Functional annotation suggested that Glyma.05G245200 and Glyma.05G247900 were involved in protein folding and oxidative metabolism, respectively, which highlights they might regulate cell cycle, growth metabolism, and nutrient remobilization during senescence. Besides, two major haplotypes of these genes exhibited highly significant phenotypic differences as Glyma.05G245200 harbored nonsynonymous mutations which changed C617T into A206V and C44T into P15L, and caused subtle alterations in its protein structure. Likewise, Glyma.05G247900 also contained a nonsynonymous mutation which changed A275G into D92G that did not alter its protein conformation. Analysis of cis-acting elements revealed that the presence of light and abscisic acid (ABA)-responsive elements in their promoters hints they might regulate soybean growth, senescence, and the stay-green trait by participating in light and hormonal signaling. These genes may serve as candidate genes for soybean stay-green and the prediction accuracy of genome-wide selection for stay-green across different marker sets ranged from 0.27 to 0.36.【Conclusion】This study identified a novel QTL, qSG5-1, and two candidate genes, Glyma.05G245200 and Glyma.05G247900, associated with the stay-green trait in soybean.

Identification of the NF-Y Gene Family and Functional Analysis of PmNF-YA8 in Broomcorn Millet

SONG YuZhen, BHEEL Chander Kumar, ZHANG YingXing, WANG Yue, SANTRA Dipak Kumar, CAO XiaoNing, WANG RuiYun

Scientia Agricultura Sinica. 2026, 59(10): 2088-2108. doi:10.3864/j.issn.0578-1752.2026.10.003

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【Objective】Nuclear factor Y (NF-Y) transcription factors regulate the expression of target genes by specifically binding to the CCAAT element in the promoter region of target genes, and play a role in plant responses to abiotic stresses such as drought and salinity. Broomcorn millet exhibits strong tolerance to drought and barrenness, serving as an indispensable crop for saline-alkali and marginal lands. Systematic elucidation of the functions of the NF-Y gene family in broomcorn millet will provide a theoretical basis for enriching the genetic theory of crop stress tolerance and promoting drought-resistant breeding practices.【Method】Genome data of broomcorn millet and bioinformatics approaches were employed to identify NF-Y family members, physicochemical properties, gene structures, construct phylogenetic trees, and predict conserved domains as well as cis-acting elements in promoters. Reverse Transcription Quantitative PCR (RT-qPCR) was used to determine the expression of these genes in different plant tissues, and the expression characteristics of PmNF-YA8 under drought stress were verified through transgenic functional validation in Arabidopsis thaliana.【Result】Based on the proso millet reference genome, 33 PmNF-Y genes (including 11 PmNF-YA, 12 PmNF-YB, and 10 PmNF-YC) were identified, encoding proteins with lengths of 122-571 amino acids, isoelectric points of 4.74-10.19, and molecular weights of 13.58-59.17 kDa. Chromosomal localization analysis showed that these 33 genes (PmNF-YA1-PmNF-YA11, PmNF-YB1-PmNF-YB12, and PmNF-YC1-PmNF-YC10) were distributed across 15 chromosomes. Two types of drought stress-responsive elements were predicted in the promoter regions of PmNF-Y family members. A total of 3, 47, and 59 NF-Y orthologous gene pairs were identified between broomcorn millet and three other plant species (Arabidopsis thaliana, rice, and maize), respectively. RT-qPCR analysis revealed that PmNF-Y genes were widely expressed in tissues such as roots, stems, and leaves. The expression level of PmNF-YA8 was up-regulated in both XHS and NM9 varieties after drought stress. Transgenic Arabidopsis thaliana lines overexpressing PmNF-YA8 were generated, and phenotypic and physiological analyses showed that under 300 mmol·L^-1 mannitol stress, the average root length of transgenic plants (14.03 mm) was longer than that of wild-type (WT) plants (9.07 mm). Additionally, transgenic plants had a lower MDA increase range (55.23%-57.12%) compared with WT plants (100.78%), with SOD and POD activities increased by 24.28%-27.43% and 163.57%-341.33%, respectively, and Pro content (151.31-175.14 μg·g^-1) higher than that of WT plants (143.78 μg·g^-1).【Conclusion】A total of 33 NF-Y family members were identified in broomcorn millet. The PmNF-YA8 gene was cloned from broomcorn millet and heterologously transformed into Arabidopsis thaliana. Its heterologous expression enhanced the drought stress tolerance of Arabidopsis thaliana plants by regulating the expression of stress-related genes, thus making PmNF-YA8 a key candidate gene for modulating drought tolerance in broomcorn millet.

Progress and Prospects of Crop Cultivation and Farming System in China

ZENG ZhaoHai, ZHOU WenBin, CHAI Qiang, SUN ZhanXiang, ZHANG JiWang

Scientia Agricultura Sinica. 2026, 59(10): 2109-2122. doi:10.3864/j.issn.0578-1752.2026.10.004

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Global population growth and rising incomes are driving sustained increases in food demand, while climate change and resource constraints impose severe challenges on production capacity. As a core discipline of agricultural science, “crop cultivation and farming system” develops theories, technologies, and patterns that not only significantly increase yields, but also improve resource use efficiency, and promote sustainable agriculture, playing a pivotal role in balancing food security with ecological protection. This study synthesizes the system’s conceptual foundations, theoretical framework, and the evolutionary trajectory of its technical structure. It highlights major contributions to securing national food supplies, increasing yield potential, improving product quality and nutrition, stimulating varietal innovation, and promoting sustainable agricultural development. The system’s development is hindered by insufficient long-term institutional support, evaluation regimes that dilute disciplinary influence, acute talent shortages, underexploited distinctive strengths, low visibility of technological advances, and limited integration with frontier technologies. In response to climate change, China has opened unprecedented opportunities for the discipline by expanding grain capacity by more than 50 million metric tons, upgrading agricultural socialized service systems, and catalyzing cross-disciplinary innovation. To capitalize on these opportunities, a “Five-sphere Integrated Plan” development pathway is proposed: (1) Strengthen basic research via long-term, networked field observatories; (2) Integrate theory and technology to enrich disciplinary content; (3) Tackle mission-critical technologies aligned with national strategies; (4) Accelerate translation through productization and scaling to expand impact; (5) Build a sustainable talent-training system. This framework provides strategic guidance for the transformation and advancement of the crop cultivation and farming system.

Regulatory Mechanisms of Spring Nitrogen Topdressing on Yield Components and Photosynthetic Resource Utilization in Winter Wheat

WANG YuanYuan, WANG Qi, MU JunYi, MI DongMing, XIE XiaoTing, HA QiQi, ZHOU Peng, REN AiXia, SUN Min, GAO ZhiQiang

Scientia Agricultura Sinica. 2026, 59(10): 2123-2137. doi:10.3864/j.issn.0578-1752.2026.10.005

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【Objective】To clarify the precise management of water and fertilizer based on spring growth stages, and to reveal the mechanism of optimizing yield components through efficient light energy utilization, thereby contributing to the increase in grain yield of winter wheat.【Method】The field experiment was conducted at the TaiGu Winter Wheat Experimental Station in Jinzhong, Shanxi Province, from 2021 to 2023. A split-plot design was adopted, with two spring nitrogen top-dressing rates (90 kg·hm^-2, N90; 120 kg·hm^-2, N120) as main plots, and four top-dressing times after regreening (10 d, 20 d, 30 d, and 40 d) as sub-plots. Through systematic surveys of tillering dynamics and measurements of canopy photosynthetic active radiation interception, combined with the fitting of the grain-filling process using the Richards model, we systematically analyzed the effects of different nitrogen topdressing treatments on the winter wheat population structure, canopy light distribution, and grain-filling characteristics. Correlation analysis was conducted to clarify the intrinsic relationships among population photosynthetic performance, tillering dynamics, and yield components.【Result】Compared with other treatments, applying 120 kg·hm^-2 of nitrogen at 30 days after regreening reduced the peak tiller number, delayed the occurrence of the tillering peak, and decreased the tiller senescence rate by 28%-43%. It also decreased the number of ineffective tillers (50-70 days after regreening) by 15%-30%, thereby significantly increasing the tiller-to-spike ratio by 10%-23%. Significantly increased the canopy PAR interception rate and extinction coefficient during the anthesis and mid-grain-filling stages, while significantly reducing the decline rate of lower-layer PAR interception during the anthesis-to-grain-filling period. Significantly increased the theoretical maximum 1000-grain weight, initial filling potential, average and maximum grain-filling rates, the time to reach maximum grain-filling rate, the duration of the gradual-increasing phase, and the grain-filling rates during the rapid-increasing and slow-increasing phases; significantly increased spike length by 3%-10%, spike weight by 8%-14%, and seed setting rate by 2%-12%.Significantly increased the number of spikes by 4%-10%, the number of grains per spike by 3%-10%, and the 1000-grain weight by 5%-10%, resulting in an increase in grain yield of 7%-20%.The Population Photosynthetic Potential during the booting-anthesis period showed a significant positive correlation with the tiller number at 45-70 days after regreening; meanwhile, the tiller number at 45-70 days after regreening was significantly and positively correlated with the spike number at maturity.The radiation interception rate in the lower layer of the canopy at the mid-grain-filling stage showed a significant positive correlation with the tiller number at 50-55 days after regreening; meanwhile, the tiller number at 50-55 days after regreening was significantly and positively correlated with the number of grains per spike. The PAR interception rate in the canopy at anthesis and mid-grain-filling stages showed a positive correlation with the tiller number at 50-55 days after regreening; meanwhile, the population photosynthetic potential during the booting-anthesis period was significantly and positively correlated with the tiller number at 50-55 days after regreening, and the tiller number at 50-55 days after regreening was significantly and positively correlated with the 1000-grain weight.【Conclusion】Application of 120 kg·hm^-2 nitrogen topdressing 30 days after regreening achieved a synergistic improvement in the number of effective spikes, grains per spike, and 1000-grain weight, thereby significantly increasing grain yield. This was realized by suppressing and delaying the tillering peak, optimizing the post-anthesis canopy light distribution, and enhancing the grain-filling process. Furthermore, correlation analysis further confirmed that the population photosynthetic potential before anthesis and the canopy photosynthetic performance after anthesis, by influencing spikelet formation and grain filling, jointly determined the final grain yield. This study provides a critical nitrogen management strategy for achieving high-yield and efficient cultivation of winter wheat in the irrigation area of the Loess Plateau by improving the population photosynthetic efficiency through integrated water and fertilizer management.

Impacts of Climate Warming on the Spatiotemporal Dynamics of Agro-Climatic Boundaries

WANG ShengNan, GAO MaoSheng, HAN WanRui, FENG HaoWei, LIN Xiang, WANG Dong

Scientia Agricultura Sinica. 2026, 59(10): 2138-2153. doi:10.3864/j.issn.0578-1752.2026.10.006

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【Objective】This study aimed to elucidate the spatiotemporal evolution patterns of agroclimatic boundaries under climate warming and their impacts on grain yield, thereby providing a scientific basis for optimizing agricultural layouts and formulating climate change adaptation strategies.【Method】Using meteorological data from 495 national stations in China (1961-2020), the spatiotemporal changes of major agroclimatic boundaries before and after climate abrupt changes were explored, including the January 0 ℃ isotherm, ≥10 ℃ accumulated temperature isopleth of 4 500 ℃, and 200, 400, and 800 mm precipitation isopleths, via methods such as Mann-Kendall change-point detection and contribution rate analysis. Their migration patterns and quantified their contribution rates to grain yield per unit area were further characterized.【Result】(1) Abrupt changes were detected in the national average January temperature in 1987, the ≥10 ℃ accumulated temperature in 2002, and precipitation in 2015, with post-change increases of 0.96 ℃, 251.19 ℃, and 53.58 mm, respectively. (2) Following the abrupt change in January mean temperature, the 0 ℃ isotherm shifted northward overall. Its eastern segment (Shaanxi, Henan, Anhui, Jiangsu, and Shandong) exhibited significant fluctuations with a northward migration amplitude of 1.5° latitude. (3) After the abrupt change in ≥10 ℃ accumulated temperature, the 4 500 ℃ accumulated temperature isopleth expanded northward, with its eastern segment (Shaanxi, Hebei, and Shandong) showing pronounced northward migration. The northernmost boundary shifted from central Hebei Province (38.9 °N) pre-mutation to traversing the Beijing-Tianjin-Hebei region (39.7 °N) post-mutation, while the western segment (Xinjiang and Gansu) showed gentle changes. (4) Precipitation isohyets exhibited a northward and westward migration trend in some regions: the 200 mm precipitation isopleth extended westward by approximately 3.0° longitude in Inner Mongolia, shrinking arid areas; the 400 mm precipitation isopleth shifted northward by about 5.5° latitude in Inner Mongolia, expanding semi-humid regions northward; and the 800 mm precipitation isopleth moved northward by around 2.5° latitude in Sichuan Province, expanding humid regions northward. (5) The contribution rates of ≥10 ℃ accumulated temperature and precipitation to meteorological grain yield per unit area increased after the abrupt change, with precipitation showing the highest contribution rate of 27.10%, while the contribution rate of January mean temperature decreased post-mutation.【Conclusion】After the abrupt change driven by climate warming, China’s January 0 ℃ isotherm and the ≥10 ℃ accumulated temperature isopleth of 4 500 ℃ have shifted northward overall, with the segment east of Shaanxi Province being particularly pronounced. The 200 and 400 mm precipitation isohyets have shifted northward and westward in the Inner Mongolia region after the abrupt change. The 800 mm precipitation isohyet has moved southward in Nanyang (Henan) and Bozhou (Anhui), while the remaining segments have shifted northward, among which the segment in central Sichuan Province showed a significant northward migration (by approximately 2.5° latitude). In the fluctuation zones of agroclimatic boundaries, changes in hydrothermal conditions have promoted an increase in grain yield per unit area.

Exploration of Resistance Evaluation System to Fusarium Ear Rot Based on Fumonisin Content

SUN Hua, AN XiaoLing, ZHENG XiaoJuan, ZHANG Shuo, GUO Ning, SHI Jie, LIU ShuSen, ZHANG HaiJian, MA HongXia

Scientia Agricultura Sinica. 2026, 59(10): 2154-2164. doi:10.3864/j.issn.0578-1752.2026.10.007

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【Objective】Maize ear rot severely impacts maize yield and quality, cultivating and planting resistant varieties is the most economical and effective prevention measure. Currently, the breeding of resistant varieties for maize ear rot mainly focuses on the severity of disease occurrence, while the accumulation of toxins within the kernels after disease occurrence is easily overlooked. This study aims to establish a resistance evaluation system to Fusarium ear rot based on fumonisin content, and to provide a basis for the breeding of new maize varieties with resistance to toxin production.【Method】The F. verticillioides with GFP-labeled was inoculated into the ears of Zhengdan 958 using the acupuncture inoculation method, then the infection and toxin production of the pathogen on the ears were investigated. The F. verticillioides was inoculated into 36 main cultivated maize varieties, and their resistance was evaluated according to the current standard, the fumonisin content in kernels of each variety was determined by enzyme-linked immunosorbent assay (ELISA), the correlation between the fumonisin content and the average disease grade was analyzed, and a resistance evaluation system for maize varieties against Fusarium ear rot was constructed based on the fumonisin content ratio. Using this evaluation system and the current industry standard simultaneously, the resistance of 142 inbred lines to Fusarium ear rot was evaluated.【Result】After the maize ears were infected by F. verticillioides, in addition to the visibly moldy kernels, there were also kernels that were symptomless but still infected. These asymptomatic kernels not only affect the judgment of the severity of ear rot occurrence, but also increase the content of fumonisin in kernels. The fumonisin content in kernels was moderately correlated with the average disease grade (r=0.39), indicating that it is impossible to select resistant varieties against fumonisin production based solely on the average disease grade. Therefore, the resistance evaluation system for maize varieties to Fusarium ear rot was established based on the fumonisin content ratio in kernels: the fumonisin content ratio<0.45, highly resistant (HR); 0.45≤the fumonisin content ratio<0.65, resistant (R); 0.65≤the fumonisin content ratio<0.85, moderately resistant (MR); 0.85≤the fumonisin content ratio<1.25, susceptible (S); the fumonisin content ratio≥1.25, highly susceptible (HS). Among the 142 inbred lines, the concordance rate between the two evaluation methods was only 14.79%, but 37.32% of the inbred lines showed moderate or higher resistance in both evaluation methods.【Conclusion】Based on the fumonisin content ratio in kernels, a new system for evaluating the resistance of maize varieties to Fusarium ear rot was established. The concordance rate between this system and the current standard was only 14.79%. The combination of these two evaluation methods provides a new method for screening and cultivating “dual resistance” maize germplasm/varieties that possess both disease resistance and fumonisin production resistance.

Receptor-Like Kinase Gene PbeCRLK2 Positively Regulates the Pyrus betulaefolia Resistance to Pear Valsa Canker

YANG JingHua, SUN E, LIU XiaoHuan, ZHANG Pan, DAI YingBao, WANG WenHui, DONG Han, ZUO CunWu

Scientia Agricultura Sinica. 2026, 59(10): 2165-2180. doi:10.3864/j.issn.0578-1752.2026.10.008

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【Objective】CRLK (calcium/calmodulin-regulated receptor-like kinase) plays an important role in low-temperature stress and starch biosynthesis, but its function in plant immunity remains unclear. This study aimed to investigate the role of PbeCRLK2 in the immune response of Pyrus betulifolia to pear Valsa canker, and to provide theoretical basis and genetic resources for the breeding of pear trees resistant to Valsa canker.【Method】The basic characteristics of PbeCRLK2 were identified through bioinformatics and subcellular localization analysis. The role of PbeCRLK2 in disease resistance was verified using transient expression in fruits and stable expression in suspension cells. Downstream immune pathways were explored by measuring reactive oxygen species (ROS) and the expression of immune-related genes. To further investigate the mechanism by which PbeCRLK2 regulates resistance to pear Valsa canker, transcriptomic analysis and qRT-PCR verification were conducted on PbeCRLK2 overexpressing cells at different time points after treatment with metabolites of V. pyri.【Result】PbeCRLK2 was a conserved cytoplasmic receptor-like kinase localized to the cell membrane. Its expression was significantly induced by metabolites of V. pyri. Both transient and stable expression of PbeCRLK2 significantly inhibited V. pyri infection and enhanced the resistance of P. betulaefolia to pear Valsa canker. Transient expression for 72 h reduced lesion diameter by 11.59% and stable expression by 44.06% on average. PbeCRLK2 enhanced pattern-triggered immunity (PTI) responses by activating WRKY22 expression. It also induced ROS bursts and up-regulated the expression of RBOHD and OXI1. Meanwhile, the expression of the key salicylic acid pathway gene ChiV was significantly up-regulated. All of these phenomena contributed to enhanced P. betulaefolia defense capabilities. GO and KEGG enrichment analyses were conducted separately for up- and down-regulated DEGs from four groups (DC_vs_YC, DT1_vs_YT1, DT2_vs_YT2 and DT3_vs_YT3) in the transcriptome data. DEGs were mainly enriched in pathways such as protein dephosphorylation, chitin catabolic processes, lipid metabolism, secondary metabolite and terpenoid biosynthesis, etc. qRT-PCR results showed that the expression trends of the selected genes were consistent with the transcriptome data, validating the transcriptomic findings.【Conclusion】PbeCRLK2 may be involved in chitin signal transduction. PbeCRLK2 enhances the resistance of P. betulaefolia to Valsa canker through the coordinated activation of PTI responses, ROS burst, and the salicylic acid signaling pathway. At the same time, it may maintain cellular immune homeostasis by dynamically regulating the expression of dephosphorylation-related genes.

Characteristics of Soil Organic Carbon Mineralization and Its Influencing Factors Under Long-Term Conservation Tillage

YE MengXue, WANG YiLun, ZHANG Qian, ZENG Chong, WU XuePing, WU HuiJun, TIAN WenZhong, LÜ JunJie, LI JunHong, MIAO YuHong, ZHENG FengJun

Scientia Agricultura Sinica. 2026, 59(10): 2181-2193. doi:10.3864/j.issn.0578-1752.2026.10.009

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【Objective】This study aimed to investigate the characteristics of soil organic carbon (SOC) mineralization and its influencing factors under different tillage practices, clarify the stability of OC under conservation tillage, and reveal the transformation patterns of C, so as to provide a scientific basis for farmland management in arid areas.【Method】This study utilized a long-term conservation tillage field experiment established in 1999 in Luoyang, Henan Province. Three treatments were selected: conventional tillage with straw removal (CT), subsoiling with straw mulching and incorporation (SS), and no-till with straw mulching (NT). Soil samples were collected from the 0-10 cm, 10-20 cm, and 20-30 cm soil layers. Soil physicochemical properties and carbon mineralization were measured, and the characteristics of SOC mineralization and its influencing factors were analyzed.【Result】After 26 years of continuous contrasting tillage practices: (1) Compared with CT, NT significantly increased soil nutrients, soil water content (SWC), redox potential (Eh), and microbial biomass carbon (MBC) content in the 0-10 cm layer. SS significantly increased soil nutrients, SWC, and bulk density (BD) in the 10-20 cm and 20-30 cm soil layers, while significantly decreasing soil inorganic carbon (SIC) content in the 0-10 cm and 10-20 cm soil layers. (2) Compared with CT, SS significantly increased the content of SOC, particulate organic carbon (POC) and its fractions, and mineral-associated organic carbon (MAOC) across 0-30 cm soil layers. NT significantly increased the content of SOC, POC, fine particulate organic carbon (f-POC), and MAOC in the 0-20 cm layers by 10.8%-20.6% compared with CT. (3) Compared with CT, both SS and NT significantly increased SOC stocks across 0-30 cm soil layers by 10.2%-56.2%. The SOC sequestration rates under SS were significantly higher than under CT by 245.7% (1999-2015), 20.3% (1999-2019), and 35.8% (1999-2024). (4) Compared with CT, SS significantly reduced the initial and final cumulative SOC mineralization in the 0-10 cm and 20-30 cm layers. NT significantly reduced the initial and final cumulative SOC mineralization in the 10-20 cm soil layer. (5) Partial Least Squares Path Modeling (PLS-PM) analysis revealed that soil physical properties (pH, SWC and BD) had a direct negative effect on MBC (path coefficient =-0.82), and indirect positive effects on MAOC (0.11) and POC (0.33). MBC had an indirect positive effect on the SOC mineralization rate (0.27) and cumulative mineralization (0.28).【Conclusion】Continuous SS practice for 25 years reduced MBC content, decreased SOC mineralization, and promoted SOC accumulation and soil fertility enhancement. MBC and MAOC were key driving factors influencing SOC mineralization.

Impact of Cultivated Land Endowment on Crop Planting Structure in Hunan Province

DING XiaoYing, CAI YanRong, SONG Min, JIN DaWei, CAO ChunXia

Scientia Agricultura Sinica. 2026, 59(10): 2194-2213. doi:10.3864/j.issn.0578-1752.2026.10.010

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【Objective】This study aimed to reveal the spatio-temporal differentiation characteristics of cultivated land endowment and crop planting structure in Hunan Province, and analyze the influencing factors of planting structure based on cultivated endowment, so as to provide a scientific basis for optimizing agricultural layout and coordinating resource utilization and crop production.【Method】Based on the remote sensing images and statistical yearbook data at county level of Hunan Province from 2017 to 2021, an evaluation index system of cultivated land endowment was constructed from three dimensions: geographical conditions, cultivated land quality and cultivated land quantity, and the type of planting structure was determined by using the proportion of crop planting area. The Dagum Gini coefficient, spatial autocorrelation model and optimal parameter geodetector were used to analyze the impact of cultivated land endowment on planting structure in 121 counties of the four major geographical regions in the province.【Result】(1) From 2017 to 2021, the endowment of cultivated land in Hunan Province generally presented the characteristics of "east-west differentiation, plain advantage", and showed a gradient strengthening trend over time, with obvious regional gap. (2) The crop planting structure was showing a trend of diversified transformation. The number of counties with single-crop dominant planting structures has decreased by 21.0%, but its proportion in 2021 was 52.9%, and its absolute advantages remained obvious. The number of counties with dual-crop dominant planting structure was relatively small and changed stably. The types of multi-crop dominant planting structures have gradually become more diverse, and their scales have continued to expand. The proportion has increased from 30.6% in 2017 to 44.6% in 2021. (3) Surface roughness and cultivated land slope were important influencing factors affecting crop cultivation in Hunan Province; average slope of the county area, the proportion of cultivated land area, surface undulation, heat conditions and soil fertility were the secondary driving factors affecting crop cultivation in Hunan Province. (4) The cultivated land endowment in the Dongting Lake area was relatively favorable, and the specialization degree of double-cropping rice cultivation was high. However, in the face of the downward trend of soil fertility, the proportion of oil crop cultivation could be reasonably increased in the future. The Changsha-Zhuzhou- Xiangtan region was limited by the amount of cultivated land and was currently facing the adjustment of the planting structure from "double to single", which would to some extent intensify the contradiction of cultivated land utilization. Further adjustments are needed in the future. The crop types in the southern part of Hunan Province were rich. However, limited by the terrain, the advantages of water and heat resources have not been fully utilized. In the future, the adjustment direction should be the cultivation of cash crops. The Greater Western Hunan region was shifting from a single single rice type to a planting structure of single rice-vegetables-other crops, making full use of the vertical climate differences in the mountains to form three-dimensional agriculture. However, the road network in this area was sparse, and the planting areas were far from the consumer market, which was not conducive to the market transactions of agricultural products.【Conclusion】The adjustment of the planting structure in Hunan Province should take into account the resource endowment characteristics of each region. Different strategies such as stabilizing grain production and expanding oil production, responding to the "double to single", developing economic crops, and implementing multi-layered agriculture should be adopted respectively for the areas of Dongting Lake, Changsha-Zhuzhou- Xiangtan, Southern Hunan, and the Greater Western Hunan region.

Distribution of Glandular Trichome and Correlation with Volatile Compounds in Phalaenopsis Floral Organs

LIN ShiYun, MA Di, YE GuangYing, CHEN HeMing, XIAO WenFang, LÜ FuBing

Scientia Agricultura Sinica. 2026, 59(10): 2214-2228. doi:10.3864/j.issn.0578-1752.2026.10.011

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【Background】Phalaenopsis is the most commercialized ornamental orchid plant globally, with floral fragrance being one of its core ornamental traits. Glandular trichomes are key physiological structures for the synthesis and release of fragrant compounds. At present, the mechanism of floral fragrance synthesis in Phalaenopsis has been preliminarily explored, but the distribution of glandular trichomes and its association with volatile components are still unclear.【Objective】The objective of this study is to clarify the physiological structural basis of fragrance release in Phalaenopsis, analyze the correlation between glandular trichome distribution and volatile components, and to provide theoretical support for understanding fragrance release mechanisms and fragrant varieties breeding.【Method】The strongly fragrant ‘Frigdaas Huang Chan’, moderately fragrant ‘Brother Sara Gold’, lightly fragrant ‘Frigdaas Hongyi’, and non-fragrant ‘Frigdaas Peach’ were used as experimental materials. Neutral red staining, scanning electron microscopy, histochemical staining and headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) were used to systematically analyze the glandular trichome morphology, distribution, cellular reserve accumulation characteristics, and differences in volatile components. Correlation analysis was conducted to clarify the relationships between glandular trichome density and volatile content, as well as odor activity values (OAVs).【Result】Glandular trichomes in Phalaenopsis were primarily distributed on the adaxial side of sepals and petals, predominantly as capitate trichomes, with minimal distribution on the abaxial side. Higher fragrance intensity was associated with greater glandular trichome density, following the order: strongly fragrant>moderately fragrant>lightly fragrant>non-fragrant. Floral organs of fragrant varieties accumulated both starch and lipids, while the non-fragrant ‘Frigdaas Peach’ accumulated only starch. The extent of lipid accumulation was closely related to fragrance intensity. Sepals were identified as the main sites of fragrance release, with representative volatile compounds including linalool, eucalyptol, myrcene, and α-pinene. The density of glandular trichomes on the adaxial side of the dorsal and lateral sepals showed a highly significant positive correlation (P<0.01) with both total volatile compound contents and total OAVs.【Conclusion】Glandular trichomes in Phalaenopsis floral organs are predominantly located on the adaxial side of sepals and are mainly capitate in type. The distribution density is positively correlated with the content of representative volatile compounds and OAVs. Additionally, lipid accumulation in floral organ cells is a significant material characteristic of fragrant Phalaenopsis varieties. This study clarifies the structural and material basis of fragrance release in Phalaenopsis, which can provide a basis for understanding the mechanisms of floral fragrance release and the selection and breeding of fragrant varieties.

Identification of Volatile Compounds and Key Aroma Components in Ornamental Crabapple Flowers

LEI Meng, LI JiaHui, LIU WeiChao, ZHANG TengXun

Scientia Agricultura Sinica. 2026, 59(10): 2229-2248. doi:10.3864/j.issn.0578-1752.2026.10.012

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【Objective】Floral fragrance is an important trait of ornamental plants. Identifying the chemical basis underlying floral scents among different ornamental crabapples can provide foundations for the fragrance breeding of ornamental crabapple and the development of aromatic products.【Method】The flowers at the full-bloom stage of six ornamental crabapples in landscape applications, namely Malus hupehensis, Malus micromalus, Malus Strawberry Parfait, Malus Kelsey, Malus Radiant and Malus Royalty, were used as plant materials. The composition and content of their volatile compounds were analyzed using headspace-solid-phase microextraction (HS-SPME) coupled with comprehensive two-dimensional gas chromatography-time of flight mass spectrometry (GC×GC-TOF MS). The key aroma compounds of each ornamental crabapple were identified through orthogonal partial least squares-discriminant analysis (OPLS-DA) coupled with odor activity value (OAV) and relative odor activity value (ROAV), and the similarities and differences in the aroma characteristics among different ornamental crabapples were further analyzed through hierarchical clustering analysis (HCA).【Result】A total of 154 volatile compounds were identified, comprising 36 terpenes and derivatives, 50 benzenoids/phenylpropanoids, 65 fatty acid derivatives, and 3 amino acid derivatives. The aroma composition and content among different tested ornamental crabapples exhibit significant differences. For each single ornamental crabapple, 53-95 kinds of compounds were detected, and the total content ranging from 7.95 to 38.31 μg·g^-1. Among the materials, M. Radiant contains the most types of volatile compounds, M. Strawberry Parfait contains the highest total content, and M. micromalus contains the fewest categories and the lowest content. The OPLS - DA model had a good fitting effect (R²X=0.972, R²Y=0.991, Q²=0.974), which could effectively distinguish the volatile compounds of different ornamental crabapples, with 27 volatile compounds making important contributions to distinguishing their aroma characteristics, mainly including linalool, indole, cinnamyl alcohol, hexa-2,4-dienal, etc. Linalool acts as the key aroma compound in M. Strawberry Parfait, M. hupehensis, M. Kelsey, and M. Royalty, while indole serves as the principal aroma material in M. Radiant and M. micromalus, with benzeneacetaldehyde also contributing significantly to the aroma of M. micromalus. These compounds form the unique aroma characteristics of each ornamental crabapple.【Conclusion】A total of 154 volatile compounds were identified in this study, and the detection performance was significantly superior to that of conventional HS-SPME-GC-MS used in previous studies. The significant differences of aroma composition and content, characteristic aroma compounds and the chemical basis underlying floral scents differences among different ornamental crabapples were clarified. Linalool, indole and cinnamyl alcohol were identified as key aroma components, and it was verified that the distinctive floral fragrance of different ornamental crabapples is not governed by a single compound, but arises from the synergistic modulation of key aroma components.

Multi-Omics Reveals Mechanisms of Lipid Stabilization in Japonica Rice During Prolonged Low-Temperature Storage

DONG Xue, LIU JiaLe, SHAO Jin, CHEN MengQiu, WU XueYou, TANG PeiAn

Scientia Agricultura Sinica. 2026, 59(10): 2249-2264. doi:10.3864/j.issn.0578-1752.2026.10.013

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【Background】Rice is a staple food for over half of the global population, and the postharvest quality deterioration of paddy rice is closely linked to lipid degradation. Low-temperature storage represents an effective strategy for maintaining rice quality and achieving green storage. However, the intrinsic mechanisms by which prolonged low-temperature storage coordinately regulates rice lipid metabolism at the level of metabolite dynamics and gene expression networks to maintain its stability have not been fully elucidated.【Objective】This study aimed to integrate multi-omics technologies to systematically elucidate biochemical and molecular mechanisms underlying lipid stability in japonica rice during long-term low-temperature storage.【Method】Fresh Nanjing 46 paddy rice was stored at 25 and 15 ℃ for 360 days, with sampling every 30 days. An integrated approach combining physiological and biochemical analyses, lipidomics, and transcriptomics was employed to systematically investigate stabilization mechanisms.【Result】Low-temperature storage effectively maintained rice lipid stability through a multi-layered regulatory network. Regarding membrane lipid metabolism, low-temperature storage downregulated PLDα1, thereby delaying the hydrolysis of phospholipids, including phosphatidylethanolamine, phosphatidylinositol, and phosphatidylcholine, and helping to maintain cellular membrane integrity. Additionally, reduced expression of OsCDase limited sphingolipid degradation, further enhancing plasma membrane stability. In terms of lipid hydrolysis, lipase activity was suppressed under low-temperature conditions, inhibiting triglyceride hydrolysis. In oxidative metabolic pathways, the downregulation of OsFAD2 and ACX1 genes inhibited polyunsaturated fatty acid synthesis and β-oxidation, thus alleviating oxidative stress. Reduced lipoxygenase (LOX，Lipoxygenase) activity at low temperatures further mitigated the oxidation of unsaturated fatty acids, thereby minimizing off-flavor formation.【Conclusion】During rice storage, lipid hydrolysis served as a critical precursor to oxidation, with both processes jointly determining quality deterioration. Low-temperature storage simultaneously inhibited lipid hydrolysis and oxidation pathways, consequently maintaining lipid compositional stability at the metabolomic level and delaying quality decline at the phenotypic level.

Research Progress on the Mechanism of Protein Glycosylation Modification in Regulating Intestinal Health of Livestock and Poultry

WANG YuXuan, GU Jiong, XIA Bing

Scientia Agricultura Sinica. 2026, 59(10): 2265-2275. doi:10.3864/j.issn.0578-1752.2026.10.014

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Since the implementation of the "antibiotic ban order" for feed in China in 2020, the livestock and poultry breeding industry has faced numerous challenges, including impaired animal growth and development, reduced feed conversion efficiency, and decreased disease resistance. Among these, the intestinal tract, as the core organ for nutrient absorption and immune defense in the body, has increasingly prominent health issues, manifested as damaged intestinal barriers, frequent inflammatory responses, and imbalances in microbial communities. The health of the intestinal tract is crucial for overall production performance, and the intestinal mucosal barrier, as the first line of defense against pathogens and toxins, maintains homeostasis through multiple mechanisms, such as mucus layer, tight junctions, immune regulation, and microbial interactions. In this process, protein O-glycosylation modification plays a key role, as it determines the structural and functional diversity of mucin proteins and directly affects barrier integrity. In recent years, with the rapid development of glycomics technology, the complex structure of glycosylation modifications can be more accurately analyzed, laying the foundation for its application in nutritional intervention and disease prevention. This article systematically summarized the main types of protein glycosylation modifications and their structural characteristics, and focused on the regional distribution differences and functional characteristics of mucin O-glycosylation modifications in the intestinal mucus layer. The article thoroughly analyzed the mechanisms of action of three important O-glycosylation subtypes (sialylation, sulfation, and fucosylation) in the intestinal mucosal barrier: Sialylation enhanced the negative charge of the mucus layer, inhibited pathogen adhesion, and regulated the function of immunoglobulins; Sulfation modification improved the stability and anti-degradation ability of the mucus layer and affected microbial recognition and colonization; Fucosylation provided carbon sources for symbiotic bacteria and activates immune axes (such as AHR/IL-22) to participate in host defense. In addition, this article systematically reviewed the latest research progress of O-glycosylation in regulating the immune response and microbial interactions in livestock and poultry, such as in models of necrotic enteritis and Salmonella infection, O-glycosylation abnormalities could lead to impaired intestinal barrier function, and supplementing specific monosaccharides (mannose, and fucosamine) could alleviate inflammation by repairing the glycan chain structure. Although significant progress has been made in related research, the precise analysis of the glycosylation modification structure and the targeted regulation of key glycosyltransferases (Fut2, St3gal, etc.) through nutritional strategies still face challenges. In the future, it is necessary to further integrate multi-omics technologies, artificial intelligence models, and synthetic biology approaches to deeply reveal the molecular mechanism of glycosylation modification in the occurrence and development of intestinal diseases in livestock and poultry, providing new ideas for the precise prevention and control of issues, such as diarrhea after antibiotic ban, and ultimately helping to improve the intestinal health level and breeding efficiency of livestock.

Establishment of Fluorescence Quantitative PCR Detection Method for Mycoplasma Contamination in Cells and Virus Live Vaccines

LIU Dan, GAO JianShuai, QIAN JiaHao, ZHANG BoYuan, LI HuiTong, DING JiaBo, XIONG Tao, SHEN QingChun

Scientia Agricultura Sinica. 2026, 59(10): 2276-2287. doi:10.3864/j.issn.0578-1752.2026.10.015

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【Background】Mycoplasma contamination poses a persistent challenge in biological research and biopharmaceutical production. Conventional detection methods, such as classical culture assays, are time-consuming and lack sensitivity, while the standard PCR is prone to inhibitor interference and incapable of quantification, failing to meet the demand for rapid and precise quality control in vaccine production or laboratory settings.【Objective】This study aimed to establish a universal, highly specific, and sensitive quantitative real-time PCR (qPCR) method for efficient screening of mycoplasma contamination in cell cultures, live viral vaccines, and biological raw materials.【Method】The SILVA_138.1_SSURef database, encompassing 16S/18S rRNA sequences of bacteria, archaea, and fungi, was utilized to extract 181 non-redundant 16S rRNA sequences from classified mycoplasma species. The hypervariable V6-V8 region was identified as the optimal target via multiple sequence alignment (MEGA 11.0). Three primers (forward primers MF1: 5′-GCAAARCTATRGARAYATAGYVGAG-3′; MF2: 5′-GCAAAGGCT TAGAAATAAGTTCGGAG-3; reverse primer MR: 5′-CCARCTCYCATRGTKTGACGG-3′) and a dual-quenched TaqMan probe (5′-FAM-ACAGRTGGTGCATGGYTGTCGTCAGCTC-BHQ1-3′) were designed using Primer Premier 5.0, with primer-probe ratios and annealing temperatures optimized to establish the qPCR assay. Validation included: (1) primer-probe specificity testing against 11 Mycoplasma/Acholeplasma species (e.g., Mycoplasma anatis, Mycoplasma bovis, Ureaplasma urealyticum); (2) sensitivity assessment via 10-fold serial dilutions (1.0×10⁸-1.0×10¹ copies/μL) of Mycoplasma synoviae BHQ03, Mycoplasma gallisepticum, and Mycoplasma hyopneumoniae, with standard curves generated; (3) specificity evaluation against four common bacteria (Salmonella, Clostridium perfringens, Escherichia coli, Brucella) and eight animal cell lines (Marc145, Vero, CEF, etc.); (4) repeatability analysis (intra- and inter-assay variability) using M. synoviae BHQ03 dilutions (1.0×10⁸-1.0×10¹ copies/μL); (5) parallel testing of 24 live viral vaccine batches (poultry, swine, and canine), 20 cell culture samples (8 types), and 8 viral seed stocks via qPCR, conventional PCR, and classical culture methods.【Result】The optimized qPCR protocol employed a two-step amplification program (56 ℃ annealing temperature). Specificity testing confirmed positive detection of all 11 Mycoplasma/ Acholeplasma strains and no cross-reactivity with non-target bacteria or cell lines. Repeatability tests showed coefficient of variation (CV) values <2% for Ct values across replicates. Sensitivity assays demonstrated limits of detection (LOD) of 1-2 copies/μL for M. synoviae, M. gallisepticum, and M. hyopneumoniae. Comparative analysis of clinical samples revealed high concordance between qPCR, conventional PCR, and culture methods, with qPCR exhibiting superior sensitivity.【Conclusion】The universal qPCR method developed in this study provided an accurate, reliable, and rapid detection tool for potential mycoplasma contamination in cell cultures and live viral vaccines.

Innovation of Citrus Triploids by Ploidy Hybridization Between Tetraploid Huyou and Four Pomelo Cultivars

SHEN ShangJie, CHEN Hui, ZHOU HongJian, HONG YaYan, YE ZheXi, HU ZhiYong, WU JinJie, WANG Gang, ZHENG LiZhen, ZHANG Lin, ZHANG Min, ZHANG Chi

Scientia Agricultura Sinica. 2026, 59(10): 2288-2298. doi:10.3864/j.issn.0578-1752.2026.10.016

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【Objective】Pummelo (Citrus grandis) is seedy under pollination to maintain fruit set and fruit quality. The objective of this study is to develop novel triploid citrus germplasm by 4x×2x intreploid hybridization, thereby providing a germplasm foundation for the breeding of seedless pummelo varieties.【Method】Allotriploids were obtained from four combinations of interploidy hybridization sharing a tetraploid Changshan Huyou (C. changshan-huyou) as their common female parent and having C. grandis Guanximiyou, C. grandis Zaoxiangyou, C. grandis Dongshizaoyou, and C. grandis Hongbaoshiyou as the male parent, respectively. Upon fruit maturity, seeds were harvested and categorized based on their sizes for inoculation on MT medium for tissue culture to obtain regenerated plants. Ploidy analysis of regenerated plants was conducted using flow cytometry, and genetic identification of triploid progenies was performed using SSR molecular markers. Additionally, systematic analysis was conducted on growth vigor, leaf morphology, and segregation patterns of monoembryony/polyembryony in triploid progenies.【Result】A total of 97 flowers were pollinated across the four hybrid combinations, yielding 29 fruits with an average fruit set rate of 29.90%. Variation in fruit set rate was observed among different male parent combinations, and the combination using Hongbaoshiyou as the male parent exhibited the highest fruit set rate (57.14%), whereas the Dongshizaoyou combination showed the lowest (9.09%). A total of 526 seeds were harvested, from which 303 regenerated plants were produced through tissue culture, resulting in an average plant regeneration rate of 57.60%. A total of 66 triploid plants were revealed by analysis of flow cytometry. These triploids were regenerated from seeds of various sizes, with the highest incidence of triploids observed in small seeds (86.36%). Triploid progenies displayed rich genetic variation in traits such as plant height and leaf morphology. In some combinations, the height of progenies was significantly greater than the female parent. The wing leaf length-to-width ratio of triploid progenies from the tetraploid Huyou×Hongbaoshiyou combination was intermediate between both parents, while in other combinations, the wing leaf length-to-width ratio of the progenies showed no significant difference from that of the female parent. Genetic identification of the 66 triploid progenies using five pairs of SSR primers showed that all triploids amplified specific bands from both parents, confirming their hybrid origin. Specifically, primer Ma3-96 amplified five types of bands in progenies from the combination of the tetraploid Huyou×Guanximiyou, and the observed ratio of these types was in accordance with the theoretical segregation ratio (4:1:1:5:1) expected for a double diploid upon chi-square test. Molecular marker identification of monoembryony/polyembryony traits indicated that the female parent, tetraploid Huyou, was polyembryonic, while the four diploid male parents were all monoembryonic. Among the 66 triploid progenies, 56 exhibited polyembryony and 10 exhibited monoembryony. The segregation ratio of monoembryony to polyembryony (5:35) in the progenies from the combination of tetraploid Huyou×Guanximiyou conformed to the theoretical expectation (1:5) upon chi-square test, indicating that the inheritance of the monoembryony/polyembryony trait in this combination followed Mendelian segregation patterns.【Conclusion】A batch of novel allotriploid germplasm was successfully generated, providing valuable genetic resources for breeding of new seedless pummelo varieties.

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