Table of Content

01 November 2026, Volume 59 Issue 21

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CROP GENETICS & BREEDING·GERMPLASM RESOURCES·MOLECULAR GENETICS

Progress and Prospects of Crop Precision Breeding Based on uORF Editing

YU BuKa, TAN YuanYuan, SHU QingYao

Scientia Agricultura Sinica. 2026, 59(21):  4697-4709.  doi:10.3864/j.issn.0578-1752.2026.21.001

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Upstream open reading frames (uORFs) are key cis-acting elements in the 5′ untranslated region (5′UTR) of eukaryotic mRNAs, which play important roles in regulation of gene translation and ultimately phenotypes. uORFs mainly block scanning ribosomes through mechanisms like leaky scanning, translation reinitiation, ribosome stalling, or nonsense-mediated mRNA decay (NMD), which consequently inhibits the translation of the downstream main open reading frame (mORF). The strength of such inhibition depends heavily on specific uORF structural features, such as the sequence around its start codon and RNA secondary structures. The uORF-based translation regulation allows plants to quickly respond to environmental signals without changing transcription levels, playing a unique role in balancing normal growth with stress adaptation. Evolutionary analysis shows that beneficial uORFs are often kept by natural selection and highly conserved. Moreover, natural uORF sequence variations in plant populations can finely adjust the translation efficiency of target genes. This provides an important genetic basis for the diversity of stress responses and agronomic traits in crops. With the development of high-throughput omics technologies, the translation profiles of many functional uORFs have been accurately mapped, providing a solid data foundation for targeted editing. Compared to editing other regions like promoters or 3′UTRs, targeting uORFs has major advantages: lower pleiotropy, higher predictability, and no need to introduce foreign sequences. Various engineering strategies—such as changing uORF length, modifying Kozak sequences, and using environment-responsive uORFs—can be achieved using genome editing technologies like CRISPR/Cas9 and prime editing (PE). These fine-tuning strategies avoid the negative side effects often caused by traditional overexpression with strong promoters, allowing for a moderate increase in target gene expression. Precisely adjusting endogenous protein levels through uORF editing has great potential for crop improvement. This includes improving broad-spectrum disease resistance and stress tolerance, optimizing traits like the growth period, and increasing nutritional quality, such as vitamin content. To help establish an efficient precision crop breeding system based on uORF editing, this review explains the main characteristics and molecular mechanisms of uORFs, summarized current uORF editing strategies and progress in trait improvement. Also discussed are t future applications and challenges of uORF editing in precision crop breeding, and the prospect of using deep learning models to improve the efficiency and predictability of uORF editing.

Identification of Excellent High Temperature Tolerant Resources in Wheat and Their Association Analysis with Agronomic Traits

YIN XiaoKang, FENG JiaYi, LI XuKang, ZHANG ZhaoXu, MA Chi, WANG RuoYu, BAI JiaQian, LAN LuoBing, ZHANG LiangFeng, LIU YiKe, ZHU ZhanWang, DING FuGong, LIU DaTong, WANG ShuPing, FANG ZhengWu, ZHANG YingXin

Scientia Agricultura Sinica. 2026, 59(21):  4710-4728.  doi:10.3864/j.issn.0578-1752.2026.21.002

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【Objective】To address the wheat yield loss caused by high temperature stress during grain filling, this study was conducted to clarify the effects of post-anthesis high temperature stress on plant phenotype, agronomic traits, yield and yield components of different wheat genotypes, establish a comprehensive evaluation system for wheat high temperature tolerance suitable for winter wheat regions in the middle and lower reaches of the Yangtze River, screen out high temperature tolerant wheat varieties, and provide identification methods and high quality germplasm resources for wheat high temperature tolerance breeding. 【Method】30 winter wheat varieties were used as experimental materials. On the 7th day after anthesis, two treatments were set for 7 days respectively, including the high temperature treatment (38 ℃ daytime/20 ℃ nighttime) and the control treatment (25 ℃ daytime/20 ℃ nighttime). After treatment, the relative chlorophyll content (SPAD value) of flag leaves, activities of ascorbate peroxidase (APX), peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT), as well as the contents of malondialdehyde (MDA), hydrogen peroxide (H₂O₂) and superoxide anion radical (O₂^-·) were measured. After harvest, grain length, grain width, grain weight per spike, thousand-grain weight and yield per plant were determined. Analysis of variance (ANOVA) was firstly adopted to eliminate indicators with no significant differences. All raw data were standardized by the high temperature tolerance coefficient (HTC). Principal component analysis (PCA) combined with the membership function method were performed to calculate the comprehensive D value for evaluating wheat high temperature tolerance. Redundancy analysis (RDA) and stepwise regression were finally used to construct the prediction model. 【Result】High temperature stress during grain filling stage caused varying degrees of leaf yellowing and grain shrinkage in all tested wheat genotypes. Under high temperature treatment, all index varied in the range of -66.82% to 210.07%, with the content of O₂^-· showing the greatest increase (210.07%) and APX activity showing the greatest decreased (-66.82%). Significant differences in HTC values were observed among different wheat cultivars, with coefficients of variation (CV) ranging from 9.522% to 115.003%. APX activity had the highest CV (115.003%), and grain width had the lowest CV (9.522%). PCA was performed on 7 indicators that met the criteria of MSA > 0.5 and KMO ≥ 0.6. 4 independent comprehensive new components were extracted, which explained 82.814% of the total variance in the original data. Furthermore, cluster analysis based on the comprehensive evaluation value D classified the 30 cultivars into three categories: 5 high temperature tolerant cultivars, 12 moderately high temperature tolerant cultivars, and 13 high temperature sensitive cultivars. The optimal regression model for wheat high temperature tolerance evaluation was established via redundancy analysis and stepwise regression: D=-0.111+0.259X₈+0.136X₁₂+0.186X₂+0.111X₁+0.137X₁₁+0.12X₁₀. The regression values (RV) of each variety were highly correlated with the D values (r=0.996). Flag leaf relative chlorophyll content (X₈), yield per plant (X₁₂), POD activity (X₂), APX activity (X₁), thousand-grain weight (X₁₁) and grain weight per spike (X₁₀) were identified as core indicators for evaluating wheat high temperature tolerance. 【Conclusion】High temperature stress during grain filling stage significantly constrained the growth and development of wheat. Using PCA and cluster analysis, 5 high temperature tolerant wheat cultivars were screened out. A comprehensive evaluation model for wheat high temperature tolerance applicable to the middle and lower reaches of the Yangtze River winter wheat was established, which can be effectively used to evaluate the high temperature tolerance of different wheat varieties at grain filling stage.

Analysis on the Composition Characteristics of Plant Height and Ear Height of Nationally Approved Maize Varieties and the Differences in Different Ecological Regions

YANG Yang, CHANG ShiHui, ZENG Bo, LI YuMing, ZHANG RuYang, XU TianJun, SUN Xuan, CHEN ChuanYong, CAO Qiang, WANG FengGe, ZHAO JiuRan

Scientia Agricultura Sinica. 2026, 59(21):  4729-4745.  doi:10.3864/j.issn.0578-1752.2026.21.003

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【Objective】Plant height and ear height are key morphological traits in maize, serving as intuitive indicators of plant architecture. Analyzing their compositional characteristics, temporal trends, and regional variation across ecological zones provides a theoretical foundation for understanding how varietal replacement reshapes plant architecture structure and how environmental gradients influence phenotypic expression. 【Method】A comprehensive dataset comprising 7 502 nationally approved maize varieties released between 2000 and 2025 was compiled. Statistical analyses were conducted to characterize the distribution, correlation, and interrelationships of plant height and ear height across variety types. A stratified threshold system for ear height was established based on empirical quantiles derived from plant height strata and corresponding ear height distributions. Adaptive performance and sources of phenotypic variation were assessed from two complementary perspectives: (1) inter-regional comparison across major ecological testing zones, and (2) intra-varietal cross-regional expression—i.e., phenotypic consistency or plasticity of the same variety grown in different environments. Temporal evolution of both traits over the 26-year period was further quantified. 【Result】Among 6 379 grain maize varieties, average plant height was 284.6 cm and average ear height was 109.0 cm. For 898 fresh maize (sweet and waxy) varieties, average plant height was 228.2 cm and average ear height was 89.9 cm. Silage maize (n=183) exhibited the tallest stature (average plant height= 302.0 cm; average ear height= 130.0 cm), whereas pop maize (n=42) averaged 245.9 cm in plant height and 112.8 cm in ear height. The ear height is divided into five grades: ultra-high ear position, high ear position, medium ear position, low ear position and ultra-low ear position, and the dividing lines are 138 cm, 108 cm, 87 cm and 51 cm respectively. Based on joint classification of plant height and ear height, grain maize predominantly fell into high and medium stem with high and medium ear position. Fresh maize clustered in medium and dwarf stem with medium and low ear position. Silage maize is mainly high stem with high ear position, and pop maize is primarily medium stem with high ear position. The statistical distribution of plant height in different ecological regions of the national regional test group showed a trend of increasing from the Dong-Nan spring-sowing regions (DN) to the medium maturity region of the Dong-Hua-Bei (DHB-M), and then decreasing to the Bei-Fang very early-maturity region (BF-VE). The ear height showed an increasing trend from the DN to the Xi-Nan (XN) and Xi-Bei (XB) spring-sowing regions. The Huang-Huai-Hai summer-sowing region (HHH), hosting the largest number of tested varieties, exhibited average plant and ear heights of 268.5 cm and 101.0 cm, respectively—predominantly medium stem and medium ear position. The second-ranked Dong-Hua-Bei spring-sowing region (DHB) were 293.3 cm and 113.7 cm, respectively, and were dominated by high stem and high ear position. Hierarchical clustering of both traits yielded congruent patterns: smaller plant architecture was observed in DN, HHH, Jing-Jin-Ji early-maturing (JJJ-E), Bei-Fang early-maturity region (BF-E), and BF-VE regions; larger plant architecture prevailed in XB, DHB, DHB-M, and Dong-Hua-Bei medium-early (DHB-ME) regions. Cross-regional phenotypic divergence increased significantly with geographical distance between the two ecological zones where the same variety was approved—most pronounced between DN and DHB, where DHB varieties averaged 54.6 cm taller in plant height and 35.8 cm higher in ear height than their DN counterparts. Notably, ear height demonstrated greater environmental sensitivity than plant height. Over the 26-year period, grain maize plant height increased modestly (average annual increment: 0.79 cm), whereas ear height declined steadily (average annual decrement: 0.19 cm). 【Conclusion】Distinct breeding objectives and divergent environmental selection pressures have driven substantial differentiation in plant architecture among maize market classes. Grain maize (the dominant category in China’s national variety portfolio) exhibits taller, bulkier architecture, reflecting a long-standing breeding emphasis on maximizing biomass accumulation for yield enhancement. In contrast, fresh maize prioritizes ear quality and harvest efficiency, resulting in shorter, which contains abundant dwarf germplasm resources to be fully excavated. Further investigation into environmental drivers (including photoperiod-temperature interactions and seasonal precipitation patterns during critical growth stages) is warranted to disentangle the relative contributions of genetic and environmental factors to phenotypic differentiation.

TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY

Effects of Late Spring Coldness at the Anther Connective Stage on the Morphology and Metabolomics of Superior and Inferior Grains in Wheat

WENG Ying, WANG Hao, LIU ZeHao, GUO YiTing, TANG YaTing, LIU Liu, ZHENG BaoQiang, LI JinCai, CHEN Xiang

Scientia Agricultura Sinica. 2026, 59(21):  4746-4764.  doi:10.3864/j.issn.0578-1752.2026.21.004

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【Objective】Late spring coldness is a major agro-meteorological disaster constraint limiting large-scale yield improvement of wheat in the Huang-Huai Plain of China. It not only affects spikelet and floret development but also influences grain weight. This study combined grain phenotype determination and untargeted metabolomics analysis to systematically investigate the morphology, grain weight, and metabolic responses of superior and inferior grains under varying degrees of late spring coldness at the anther connective stage, aiming to elucidate the intrinsic mechanisms underlying the differences in grain filling between superior and inferior grains of wheat with different resistances to late spring coldness from the perspectives of grain sink capacity formation and metabolic regulation. 【Method】In this study, the cold-tolerant wheat cultivar Yannong 19 (YN19) and the cold-sensitive cultivar Xinmai 26 (XM26) were used as experimental materials. Low-temperature treatments were conducted in an artificial climate chamber at the anther connective stage of young spike differentiation to simulate late spring coldness conditions in the field, with three temperature gradients (CK: 10 ℃; T1: 2 ℃; T2: −2 ℃). At maturity, the main agronomic traits of wheat were investigated. Grain morphology and grain weight were dynamically measured at 7, 14, 21, 28, and 35 days after anthesis to analyze the changes in grain sink capacity and grain weight under different temperature treatments. Superior and inferior grains were collected at 14 and 21 days after anthesis, respectively, and untargeted metabolomics analysis was performed using liquid chromatography-mass spectrometry (LC-MS). Multivariate statistical analysis was combined to screen differential metabolites, and the shared and specific responses of metabolites among different cultivars, stress intensities, grain-filling stages, and grain positions were compared. KEGG was used for metabolic pathway enrichment analysis. 【Result】Late spring coldness significantly inhibited the increase in grain sink capacity and reduced grain volume at maturity. In both wheat cultivars, the thousand-grain weight of superior and inferior grains decreased significantly with increasing stress intensity, with a more pronounced reduction observed in inferior grains. Metabolomic analysis identified a total of 2 474 metabolites, including 1 118 annotated metabolites. The number of differentially accumulated metabolites increased markedly with increasing intensity of late spring coldness, and XM26 exhibited more differentially accumulated metabolites than YN19. Only a small number of common differentially accumulated metabolites were shared among different treatments and cultivars. Notably, L-phenylalanine in superior grains at 21 d was identified as a common significantly different metabolite in multiple comparison groups. KEGG pathway enrichment analysis revealed that, under late spring coldness, differentially accumulated metabolites in superior grains were mainly enriched in energy metabolism-related pathways, such as the tricarboxylic acid (TCA) cycle and glycolysis/gluconeogenesis. In contrast, differentially accumulated metabolites in inferior grains were predominantly enriched in pathways associated with energy compensation and antioxidative responses, including starch and sucrose metabolism, oxidative phosphorylation, and glutathione metabolism. 【Conclusion】Late spring coldness exacerbated the differences in grain filling between superior and inferior grains by disrupting energy metabolism and assimilate accumulation during the grain-filling period. These findings provided the metabolomic evidence for elucidating the damage mechanisms of late spring coldness in wheat and for the breeding of cold-tolerant wheat cultivars.

Assessment Model for Pre-Harvest Sprouting of Winter Wheat Due to Persistent Rainfall Disasters During Maturity-Harvest Period in Henan Province

PENG JiYong, SHANG DongYao, LI JunLing, XUE ChangYing, HU LiTing, YU WeiDong

Scientia Agricultura Sinica. 2026, 59(21):  4765-4783.  doi:10.3864/j.issn.0578-1752.2026.21.005

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【Objective】The period from maturity to harvest of winter wheat is a critical period for grain quality and yield, and persistent rainfall disasters during this period cause irreversible losses to wheat yield, quality, and seed security. Through quantitative assessment of the impact of persistent rainfall disasters during the maturity-harvest period on pre-harvest sprouting (PHS) in winter wheat, this study aims to provide a theoretical and scientific basis for PHS risk zoning, disaster early warning, quantitative evaluation, trend projection, and the developments of field management measures. 【Method】Field and laboratory PHS experiments were conducted on three major winter wheat (Xinmai26, Aikang58, and Yangmai15) cultivars widely grown in Henan Province during 2024-2025. Pre-harvest sprouting rate of winter wheat under persistent rainfall conditions was investigated through observational experiments to determine the variation pattern of the PHS rate over time. Subsequently, based on field survey data of PHS in 2023, correlation analysis and analytic hierarchy process (AHP) were applied to identify the dominant meteorological drivers of PHS. On this basis, an evaluation model for pre-harvest sprouting rate (PHSR) in winter wheat was developted, followed by systematic error analysis. 【Result】The PHS experiment indicated that the PHS rate of winter wheat followed a Logistic growth curve over time. The PHS rate showed significant correlations with cumulative precipitation, mean temperature, and the mean sunshine duration, with correlation coefficients of 0.416 (P<0.01), 0.318 (P<0.05), and -0.303 (P<0.05), respectively. Based on experimental data and key meteorological factors, a PHSR assessment model was developed for winter wheat during the maturity-harvest period under persistent rainfall disasters. The model demonstrated a correlation coefficient of 0.85 (P<0.01) between simulated and observed values, with a mean absolute error of 1.91% and a mean relative error of 4.98%. The simulated PHS rates for typical years were in good agreement with records from published literatures. Spatially, PHS risk during the maturity-harvest period showed an obvious spatial pattern of high values in the southern Henan and low values in northern Henan. Among the selected years, the highest provincial average PHS rate was recorded in 1991, followed by 2023. 【Conclusion】By coupling the dynamic PHS response derived from experimental with key meteorological forcing factors, this study developed a quantitative evaluation and prediction method for the PHS rate of winter wheat under persistent rainfall disasters has been established. The method could be applied to risk zoning, pre-disaster early warning and post-disaster quantitative assessment of PHS triggered by persistent rainfall disasters during the maturity-harvest period of winter wheat in Henan Province.

Analysis and Countermeasure of Xinjiang Cotton Industry Status and Its Influencing Factors

TIAN LiWen, ZHANG Sheng, TIAN CongHua, MA Ting, CUI JianPing, FANG YanFei, LUO HongHai, LOU ShanWei

Scientia Agricultura Sinica. 2026, 59(21):  4784-4801.  doi:10.3864/j.issn.0578-1752.2026.21.006

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This paper systematically reviewed the development status and key influencing factors of the cotton industry in Xinjiang, aiming to provide the decision-making references for industrial transformation, upgrading, and high-quality development. Based on statistical data from 2014 to 2025 and authoritative public sources, a multidimensional analysis was conducted along the entire industrial chain—covering cotton cultivation, processing, and textiles—and encompassing natural resources, technological progress, policies and institutions, the market environment, and socio-economic conditions, thereby identifying the core factors and their mechanisms in each dimension. The results indicated that in 2025, total cotton output in Xinjiang reached 6.165 million tons, with high-quality cotton accounting for 72.3%, forming an industrial development pattern characterized by “continuous expansion in scale, stable spatial distribution, and simultaneous quality improvement”. Benefiting from the agglomeration effect of the relocation of the textile industry from eastern China to Xinjiang, a complete cotton industrial chain integrating cultivation, spinning, weaving, dyeing, and garment manufacturing has been established, with the gross output value of the entire chain exceeding 220 billion yuan; the scale of the textile industry has continued to expand, and the share of locally produced cotton processed within Xinjiang has steadily increased. The influencing factors were interdependent and mutually restrictive. Although water resources impose rigid constrained on the scale of the industry, Xinjiang possesses unique natural resource advantages in sunlight and land, and was strongly supported by technological and policy assistance—notably, the cotton target price subsidy has formed a stable “fixed every three years” mechanism that promoted industrial transformation. Currently, Xinjiang's cotton industry still lacks pricing dominance and industry influence in international markets, facing both opportunities and challenges in the international competitive and trade environment, while cotton cultivation costs continue to rise.The Xinjiang cotton industry was at a critical stage of profound transformation from a “scale-expansion model” to a “quality-efficiency model”. To achieve the 2026 regulatory target of a cotton planting area of (240±3.3)×10⁴ hm², under the premise of prioritizing the interests of basic farming households, efforts should focus on reducing low-quality and low-efficiency cotton fields, areas of groundwater over-extraction, and illegally reclaimed land. It was also recommended to synergistically strengthen technological empowerment, improve the policy system, promote green transformation, and expand international markets, thereby striving to build a modern full industrial system of cotton cultivation and textile and apparel that was the world’s largest in scale, most complete in chain, and leading in quality and efficiency, and driving the Xinjiang cotton industry toward higher quality and greater sustainability.

PLANT PROTECTION

Analysis of the Fungal Community Composition in Maize Kernels and the Toxigenic Capacity of Dominant Fusarium Species in China

CHENG MingXin, CHEN WenChan, WEI KaiWei, ZHANG Sai, ZUO YuJie, SU QianFu, LIU Ning, CAO ZhiYan, DONG JinGao

Scientia Agricultura Sinica. 2026, 59(21):  4802-4814.  doi:10.3864/j.issn.0578-1752.2026.21.007

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【Objective】This study aimed to clarify the composition, regional distribution characteristics, and annual succession patterns of pathogens in maize kernels from major maize-producing areas in China, systematically analyze the toxigenic capacity of dominant pathogens, and to provide scientific basis and data support for the control of mycotoxin contamination and the quality and safety assurance of maize during storage. 【Method】From 2022 to 2025, maize kernel samples were continuously collected from 41 regions across 14 provinces (autonomous regions) in China for four consecutive years, and pathogens were isolated and purified. Morphological and molecular biological methods were used to identify the contaminant fungi. The pathogen species and isolation frequency were counted to analyze their distribution characteristics and dynamic changes. The toxigenic capacity of Fusarium verticillioides and F. graminearum was determined, and the differences in toxigenic capacity of the two species among different maize-producing areas were analyzed and compared. 【Result】A total of 5 885 fungal strains were isolated, predominantly including Fusarium spp., Penicillium spp., Aspergillus niger, Trichoderma spp., A. flavus, and other fungi. Their corresponding isolation frequencies were 67.82%, 17.72%, 7.31%, 2.97%, 2.70%, and 1.48%, respectively. Among them, Fusarium spp. had the highest isolation frequency. Within the genus Fusarium, F. verticillioides was the predominant species. A total of 3 061 strains were isolated during the four-year investigation, accounting for 52.01% of the total strains. This was followed by F. graminearum, F. proliferatum, and F. oxysporum, with isolation frequencies of 11.03%, 3.14%, and 1.58%, respectively. F. culmorum was only detected in 2022 (3 strains). Among molds, Penicillium spp. and A. niger were the main contaminants, with isolation frequencies of 17.72% and 7.31%, respectively. The toxigenic capacity of the isolated F. verticillioides and F. graminearum were determined. The results showed that the FB₁ production of F. verticillioides ranged from 0.07 to 4 916.92 μg·g^-1, and FB₂ ranged from 0.02 to 5 573.14 μg·g^-1. Significant differences in toxigenic capacity were observed among strains from different production areas. Strains isolated from the Huang-Huai-Hai maize-producing area exhibited higher toxigenic capacity, with the maximum FB₁ and FB₂ production levels reaching 4 916.92 and 5 573.14 μg·g^-1, respectively. The Northeast maize-producing area ranked second, with maximum FB₁ and FB₂ production levels of 2 070.29 and 468.51 μg·g^-1. By contrast, the Northwest maize-producing area showed overall lower toxigenic capacity, with a concentrated distribution and a smaller proportion of high-toxin-producing strains; the maximum production levels of FB₁ and FB₂ were only 20.91 and 30.76 μg·g^-1, respectively. The DON production of F. graminearum ranged from 1.24 to 3.43 μg·g^-1. Overall the three major maize-producing areas (Northeast, Northwest, and Huang-Huai-Hai) exhibited similar toxigenic distribution patterns with only minor variations, and no significant regional differences were observed. 【Conclusion】F. verticillioides is the primary contaminant of maize kernels in China, with its population structure varying across regions and years. The toxigenic capacity (FB) of F. verticillioides varies significantly among different maize-producing areas, and high-toxin-producing strains are predominantly distributed in the Huang-Huai-Hai and Northeast maize-producing areas.

Biocontrol Potential and Mechanism of Bacillus velezensis C1-17 Against Peach Brown Rot

QIN Ying, YIN WeiXiao, LUO ChaoXi

Scientia Agricultura Sinica. 2026, 59(21):  4815-4830.  doi:10.3864/j.issn.0578-1752.2026.21.008

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【Objective】Peach brown rot, caused by Monilinia spp., is a severe fungal disease leading to substantial economic losses to the peach industry. This study aims to evaluate the biocontrol potential of Bacillus velezensis strain C1-17 against peach brown rot and to elucidate its antifungal mechanisms, thereby providing a novel strain resource and theoretical basis for green management of this disease. 【Method】A previously obtained B. velezensis C1-17 strain was used, the in vitro antifungal activity and in vivo biocontrol efficacy of C1-17 against M. fructicola, the dominant pathogen of peach brown rot, were determined by dual-culture plate confrontation assay, fruit immersion with bacterial suspension, and cell-free culture filtrate assay, respectively, to evaluate its biocontrol potential. Morphological and ultrastructural changes in the pathogen hyphae after treatment were investigated by using light microscopy, scanning electron microscopy, and transmission electron microscopy. Plasma membrane integrity and intracellular reactive oxygen species (ROS) levels of the pathogen were detected using propidium iodide (PI) staining and the DCFH-DA fluorescent probe, respectively. The ability of C1-17 to produce extracellular antimicrobial active compounds, including proteases, cellulases, and siderophores, was assessed using specific culture media. Expression changes of defense-related genes (PpPR1, PpNPR1, PpMYC2, PpJAZ5, PpPAL1, PpPOD) in peach fruit following C1-17 treatment and under pathogen infection were analyzed by reverse-transcription quantitative real-time PCR (RT-qPCR). Peach fruits were sprayed with 10% C1-17 bacterial suspension and tebuconazole, respectively, and then inoculated with spore suspensions of DMI-resistant and DMI-sensitive strains. Disease incidence was investigated and control efficacy was calculated to evaluate the control efficacy of C1-17 against different resistant strains. 【Result】The fermented broth of C1-17 showed a control efficacy of 93.25% against peach brown rot at a low concentration of 2% (V/V). Its cell-free culture filtrate at 1% (V/V) inhibited mycelial growth of M. fructicola by 95.93% and reduced the conidial germination rate to 3%. After treatment with 1% (V/V) C1-17 cell-free culture filtrate, pathogen hyphae exhibited swelling, vacuolation, wrinkling and disruption, plasmolysis, and dissolution of organelles such as mitochondria. PI staining and DCFH-DA detection confirmed loss of plasma membrane integrity and massive accumulation of intracellular ROS, suggesting that membrane damage and oxidative burst are important antifungal mechanisms. C1-17 also produced extracellular active substances such as proteases, cellulases, and siderophores. Spraying C1-17 alone did not significantly induce the expression of peach defense-related genes. However, under M. fructicola infection, C1-17 pretreatment specifically up-regulated the expression of salicylic acid pathway-related genes (PpPAL1 and PpPR1) and PpPOD at the late stage of infection (48 h). The 10% C1-17 suspension exhibited good control efficacy (≥94.50%) against both DMI-resistant and DMI-sensitive strains of M. fructicola. Notably, its efficacy against DMI-resistant strains was superior to that of 20 μg·mL^-1 tebuconazole, and no cross-resistance with DMI fungicides was observed. 【Conclusion】B. velezensis C1-17 shows promising biocontrol potential against peach brown rot. By secreting antifungal substances, C1-17 directly disrupts hyphal morphology and plasma membrane integrity of M. fructicola and induces intracellular ROS accumulation. In addition, at the late stage of pathogen infection, it selectively activates the salicylic acid signaling pathway and the phenylpropanoid metabolic pathway, thereby achieving efficient control of peach brown rot.

Odorant-Binding Protein OBP4 Mediates Repellent Behavior of Bemisia tabaci to Host Plant Volatiles

JI Yuan, SUN YuXiang, GONG Cheng, LIU HangWei, LUO Chen

Scientia Agricultura Sinica. 2026, 59(21):  4831-4840.  doi:10.3864/j.issn.0578-1752.2026.21.009

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【Background】The whitefly, Bemisia tabaci, is a highly polyphagous agricultural pest of global significance, exhibiting a distinct preference for specific host plants. Odorant-binding proteins (OBPs), which specifically bind to environmental odor molecules, play a pivotal role in insect behaviors such as host location, oviposition site selection, and predator avoidance. 【Objective】The purpose of this study is to deeply elucidate the molecular mechanism of OBP in the chemosensory and behavioral regulation of B. tabaci, reveal the physiological basis of its host adaptability, and to provide a theoretical basis for the development of new green prevention and control technologies based on olfactory interference. 【Method】Quantitative real-time PCR (qRT-PCR) was used to detect the expression profile of BtabOBP4 in different developmental stages (egg, 1st-4th instar nymphs, adult) and different adult tissues (head, thorax, abdomen) of B. tabaci. The full-length BtabOBP4 was cloned, and the recombinant BtabOBP4 protein was induced for heterologous expression and purified. Fluorescence competitive binding assays were conducted to screen the binding capacity of BtabOBP4 to plant volatiles and secondary metabolites. Y-tube olfactometer was used to determine the behavioral tropism of B. tabaci to candidate ligands. Feeding-mediated RNA interference (RNAi) technology was employed to silence the BtabOBP4 to verify its regulatory effect on chemosensory behavior in B. tabaci. 【Result】BtabOBP4 showed the highest expression level at the 3rd instar nymph stage of B. tabaci, and exhibited sexual dimorphism in the adult stage (male was approximately 4 times that of female), and was specifically enriched in the head. BtabOBP4 could specifically bind to myrcene, β-ionone, and α-pinene (the K_i values were 25.68, 43.95, and 33.65 μmol·L^-1, respectively). Notably, 100 mg·L^-1 myrcene, 100 mg·L^-1 β-ionone, and 1 000 mg·L^-1 α-pinene repelled B. tabaci by 33%, 43%, and 44%, respectively. After 24 h of dsRNA feeding, the silencing efficiency of BtabOBP4 reached 55% in females and 51% in males. The repellent responses of B. tabaci to myrcene and α-pinene were completely abolished, while the repellency toward β-ionone was significantly attenuated. 【Conclusion】BtabOBP4 is highly expressed in the 3rd instar nymphs and male adults of B. tabaci, with specific enrichment in the head tissue, suggesting its pivotal role in chemical communication. The BtabOBP4 protein exhibits specific binding affinity to myrcene, β-ionone, and α-pinene. Notably, silencing of BtabOBP4 via RNA interference significantly abolished or attenuated the repellent behavior of B. tabaci toward these compounds. These findings indicate that BtabOBP4 functions as a key olfactory receptor mediating host plant recognition and selection in B. tabaci, regulating repellent responses by perceiving specific plant volatiles.

SOIL & FERTILIZER·WATER-SAVING IRRIGATION·AGROECOLOGY & ENVIRONMENT

Jinggangshan Model: Theory and Application of Integrated Management Practices in Southern Red Soil Hilly Region

PENG XinHua, GUO ZiChun, HUANG ShangShu, XIONG Peng, LIU Ming, LIU KaiLou, LIU Jia, HUANG TaiQing, ZHONG YiJun, ZHANG HuiMin, HE TieGuang, DENG ShaoYong, NIE Jun, ZHAO XiaoMin, ZHANG JiaBao

Scientia Agricultura Sinica. 2026, 59(21):  4841-4853.  doi:10.3864/j.issn.0578-1752.2026.21.010

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The red soil region of southern China is a crucial base for tropical and subtropical grain production, fruits and economic forests, which accounts for approximately 23% of the country's land and supports 40% of its population, thus playing an irreplaceable role in ensuring regional food security. However, due to long-term intensive and inappropriate use, the red soils in this region face multiple challenges, including severe acidification, fertility decline, soil compaction, soil erosion, and seasonal drought, thereby constraining high-quality agricultural development. To address the coexisting soil constraints, the Institute of Agricultural Resources and Regional Planning of the Chinese Academy of Agricultural Sciences and the Institute of Soil Science, Chinese Academy of Sciences, in collaboration with universities and research institutions in Jiangxi, Hunan and other provinces, have conducted joint researches. Through more than two decades of research and practice, they developed the Jinggangshan Model, which integrated cropland quality improvement, agricultural productivity enhancement, and ecological conservation. The model was centered on a four-in-one ecological layout featuring “rice cultivation in valley bottoms, cash crops on hill foots, fruit trees on mid-hills, and forest conservation on hill tops.” It integrated four key technological systems: a quality improvement, green, high-yield, and efficient production for double-cropping rice fields; technologies for mitigating multiple barriers (acidity, low fertility, compaction, and erosion) in drylands to boost productivity; systems for synchronizing orchard fertility improvement, quality enhancement, and ecological protection; technologies for ecological conservation on mountain tops combined with under-forest economy development. The model also established highly connected, multifunctional ecological corridors and an intelligent decision-support system for precision crop management covering the entire production cycle from sowing to harvest. This study elaborated on the model's historical development, conceptual basis, technological systems, extension mechanisms, and outcomes. It also discussed the challenges it faced and directions for future development. The Jinggangshan Model represented a practical approach to the integrated management of the red soil region of southern China by coordinating cropland quality improvement, agricultural productivity enhancement, and ecological conservation, and could provide the scientific and technological support for high-quality green agricultural development in the region.

Spatial Variation Characteristics and Influencing Factors of Soil Organic Matter Fractions in Drylands of the Songnen Plain

YAO Yi, ZHANG SiYu, HAO SiQi, LI ShuangYi, SUN LiangJie, CHEN JingYu, AN TingTing, WANG JingKuan

Scientia Agricultura Sinica. 2026, 59(21):  4854-4864.  doi:10.3864/j.issn.0578-1752.2026.21.011

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【Objective】 This study explored the spatial distribution characteristics and influencing factors of soil organic matter (SOM) fractions in the drylands of the Songnen Plain, so as to provide a basis for SOM improvement and black soil protection in Northeast China. 【Method】Taking the dryland soil as the research object, 200 surface soil samples (0-20 cm) were collected in the Songnen Plain in June 2023. Then, soil samples were separated into particulate organic matter (POM) and mineral-associated organic matter (MAOM) fractions by the particle size fractionation method. Combined with classical statistical methods and the Random Forest model, this study investigated the distribution characteristics of SOM fractions and explored the influences of climate, topography, soil properties and vegetation factors on them. 【Result】The average content of MAOM and POM was 24.7 and 5.71 g·kg^-1, respectively, accounting for an average of 70.9% and 17.1% of the total SOM content, respectively. In the Songnen Plain region, both fractions exhibited a decreasing trend from the northeast to the southwest regions. MAOM content (r=0.93, 0.66, and 0.51, respectively) and POM content (r=0.75, 0.25, and 0.36, respectively) were extremely significantly (P<0.01) positively correlated with SOM, clay content, and altitude. MAOM (r=-0.33, -0.57, -0.79, -0.73, and -0.40, respectively) and POM (r=-0.21, -0.26, -0.55, -0.58, and -0.24, respectively) were extremely significantly (P<0.01) negatively correlated with pH, bulk density, annual mean temperature, effective accumulated temperature, and normalized difference vegetation index. Random Forest model analysis showed that effective accumulated temperature, annual mean temperature, and clay content extremely significantly (P<0.01) affected the spatial variation of MAOM fraction, with explanation degrees of 33.7%, 32.7%, and 23.8%, respectively; effective accumulated temperature, annual mean temperature, and available phosphorus extremely significantly (P<0.01) affected the spatial variation of POM fractions, with explanation degrees of 26.1%, 25.2%, and 22.8%, respectively. 【Conclusion】 The soil organic matter fractions in the drylands of the Songnen Plain showed an obvious spatial distribution pattern of being higher in the northeast and lower in the southwest, and annual mean temperature and effective accumulated temperature were the key factors driving their spatial distribution.

Layered Nitrogen Fertilization Improves Soil Nitrogen Fractions and Enhances Nitrogen Utilization and Yield in Maize

WANG Bin, WANG YanQun, FU Xin, MEN Jie, WANG Yang, NING Peng, PENG ZhengPing

Scientia Agricultura Sinica. 2026, 59(21):  4865-4881.  doi:10.3864/j.issn.0578-1752.2026.21.012

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【Objective】This study aimed to determine the optimal application depth and ratio of nitrogen fertilizer for high-yield and high-efficiency summer maize, and to reveal the mechanism of efficient nitrogen utilization. 【Method】 Two-year field micro-plot experiment and a one-year mechanized large-plot experiment were conducted using summer maize as the test crop. Under micro-plot conditions, six treatments were established: no nitrogen application (N_0:0), single-layer nitrogen application was applied only to the 0-20 cm soil layer (N_1:0), dual-layer nitrogen application was applied to both the 0-20 cm and 20-40 cm soil layers at four application ratios between the two layers: 4:1 (N_4:1), 3:2 (N_3:2), 2:3 (N_2:3), and 1:4 (N_1:4). Comprehensive analyses were conducted on soil nitrogen fractions, microbial community structure, plant dry matter and nitrogen accumulation, nitrogen recovery rate, and yield during key growth stages of maize, and the optimal treatments were identified as N_4:1 and N_3:2. Subsequently, a mechanized large-plot experiment was carried out with N_4:1, N_3:2, N_1:0, and N_0:0 treatments to verify the nitrogen fertilizer efficiency and yield of the optimal treatments. 【Result】 (1) Compared with the N_1:0 treatment, layered nitrogen fertilization increased aboveground dry matter and nitrogen accumulation in maize, and optimized the distribution of assimilates to grains, with the N_3:2 treatment performing the best. (2) Layered nitrogen fertilization effectively promoted nitrogen supply in the 20-40 cm soil layer by increasing the content of total nitrogen, inorganic nitrogen, particulate organic nitrogen, and microbial biomass nitrogen in this layer. The N_3:2 treatment could enhance the stability of nitrogen in deeper soil layers while maintaining the nutrient content of the surface soil without reduction. (3) Layered nitrogen fertilization altered the soil microbial community structure; the N_3:2 treatment increased the species richness of the fungal community and promoted the relative abundance of beneficial fungal phyla (e.g., Mortierellomycota, Basidiomycota). Under the N_3:2 treatment, while ensuring no reduction in surface soil enzyme activity, the activities of urease and N‑acetylglucosaminidase in the 20-40 cm soil layer increased by 10.6%-33.4% and 2.1%-34.6%, respectively. (4) Over the two-year field micro-plot experiment, the N_3:2 treatment significantly increased average yield, 100‑grain weight, and number of grains per spike by 6.6%, 14.4%, and 7.6%, respectively, compared with the N_1:0 treatment, and significantly improved nitrogen recovery rate, agronomic efficiency, partial factor productivity and cumulative utilization rate. In the mechanized large-plot experiment, the N_3:2 treatment achieved significantly higher yield and efficiency than that under N1:0 treatment. 【Conclusion】The N_3:2 treatment (layered nitrogen application at 0-20 cm and 20-40 cm soil layer with a ratio of 3:2) effectively coordinated soil nitrogen supply with crop nitrogen demand, improved the soil microbial environment, significantly enhanced plant dry matter and nitrogen accumulation, and achieved a win‑win outcome of high yield and high efficiency.

Effects of Irrigation Level and Nutrient Solution Concentration on Yield, Quality, and Water-Fertilizer Use Efficiency of Tomato Growing in Coconut Coir Bag Culture

QIANG XiaoMan, LIU ShengXing, ZHANG XianBo, WANG JingLei, WANG ChunTing, ZHU TianTian, WANG BoJuan, LIU Hao

Scientia Agricultura Sinica. 2026, 59(21):  4882-4903.  doi:10.3864/j.issn.0578-1752.2026.21.013

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【Objective】This study aimed to investigate the effects of irrigation levels and nutrient solution concentrations on the growth characteristics, yield, fruit quality, and water-fertilizer use efficiency of tomato growing in coir bag culture, and to determine an appropriate water and nutrient management mode for coir-grown tomatoes, so as to provide a reference for irrigation scheduling and nutrient solution application in coir bag culture. 【Method】Two factors, namely irrigation lower limit and nutrient solution concentration, were set in the experiment. The irrigation lower limit included three levels: 60% (W1), 70% (W2), and 80% (W3) of the water-holding capacity (FC) of the coir bag. The nutrient solution concentration also included three levels: 0.8-fold (F1), 1.0-fold (F2), and 1.2-fold (F3) of the Hoagland formula. The effects of different treatments on tomato growth and development, photosynthetic characteristics, nutrient accumulation and utilization, yield, fruit quality, water use efficiency and fertilizer partial factor productivity were systematically analyzed. In addition, a comprehensive evaluation system was established by integrating the entropy weight method, analytic hierarchy process (AHP), and TOPSIS method to optimize irrigation and nutrient solution management indicators. 【Result】Both irrigation level and nutrient solution concentration significantly affected tomato plant height, leaf area index, aboveground biomass, and photosynthetic parameters, as well as nitrogen, phosphorus and potassium accumulation. Increasing irrigation level significantly promoted plant growth and enhanced photosynthetic capacity. Under medium and high irrigation conditions, appropriately increasing nutrient solution concentration was beneficial to nutrient uptake and biomass accumulation. In the two-year experiment, W3F3, W3F2 and W2F2 all produced relatively high yields, with no significant differences among them (P>0.05). Among these treatments, W2F2 maintained a relatively high yield, while achieving the highest water use efficiency in both years, together with relatively good partial factor productivity of fertilizer and overall fruit quality. The TOPSIS comprehensive evaluation showed that the relative closeness coefficients of W2F2 were 0.7654 and 0.8177 in the two years, respectively, ranking first among all treatments. 【Conclusion】Under the experimental conditions, the W2F2 treatment, with an irrigation lower limit of 70% FC combined with a 1.0-fold Hoagland nutrient solution, could better coordinate tomato yield, fruit quality and resource use efficiency, and thus could be recommended as a relatively suitable fertigation management mode for greenhouse tomato growing in coir bag culture.

HORTICULTURE

Comprehensive Stage-Specific Evaluation of Salt-Alkali Tolerance and Tetraploidization Effects in Diploid and Tetraploid Non-Heading Chinese Cabbage

TANG WeiHua, ZHANG ZhiLin, YAN ZhiMing, LIU TongKun, HOU XiLin

Scientia Agricultura Sinica. 2026, 59(21):  4904-4923.  doi:10.3864/j.issn.0578-1752.2026.21.014

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【Objective】This study aimed to clarify the differences in salt-alkali tolerance between diploid and tetraploid non-heading Chinese cabbage with the same genetic background across different salt types and developmental stages, to determine the effects of tetraploidization and its dependence on genetic background, and to identify elite materials combining stress tolerance, yield performance, and breeding potential, thereby providing a basis for germplasm evaluation and ploidy improvement in non-heading Chinese cabbage. 【Method】Fifteen pairs of diploid and tetraploid (2X/4X) non-heading Chinese cabbage with corresponding genetic backgrounds were used as experimental materials. NaCl and NaHCO₃ stresses were applied at the germination and seedling stages, respectively, and NaCl drip-irrigation stress was imposed throughout the whole growth period under field conditions. Concentration gradients of NaCl and NaHCO₃ were established at the germination stage; 450 mmol·L^-1 NaCl and 80 mmol·L^-1 NaHCO₃ were applied at the seedling stage; and 200 mmol·L^-1 NaCl was supplied by drip-irrigation in the field, with soil EC_1:5 monitored to characterize salinity intensity. Germination, morphological, physiological, photosynthetic, and yield-related traits were measured. Salt-tolerance coefficients (STCs) were calculated, and a comprehensive salt-tolerance index (D-value) was obtained using principal component analysis combined with the membership function method. The MGIDI index, Fernandez four-quadrant method, paired t-tests, correlation analysis, and regression analysis were further used to evaluate material tolerance, yield performance, and ploidy effects. 【Result】Salt-alkali tolerance in non-heading Chinese cabbage showed clear salt-type differences and developmental-stage specificity. At the germination stage, NaHCO₃ stress caused stronger overall inhibition than NaCl stress. Treatment with 250 mmol·L^-1 NaCl effectively enlarged differences among materials; under NaHCO₃ stress, 40 mmol·L^-1 was sufficient to reveal material differentiation, whereas 60 mmol·L^-1 produced greater overall dispersion and a wider D-value distribution, making it more suitable for comprehensive evaluation at the germination stage. At the seedling stage, responses to NaCl and NaHCO₃ were not fully consistent, and some materials with advantages at the germination stage showed reduced tolerance at the seedling stage, indicating that germination-stage results can not directly substitute for evaluations at the seedling stage or throughout the whole growth period under field conditions. In the field evaluation, D-value rankings were largely consistent with MGIDI rankings (Spearman ρ=-0.775, P=4.87×10^-7), demonstrating good robustness of the multi-trait D-value evaluation. However, Fernandez yield correction showed that most materials with high D-values did not fall into the high-yield and stress-tolerant Group A, suggesting that high comprehensive tolerance does not necessarily indicate high yield under salt stress. The ploidy effect was strongly condition-dependent. Only under NaHCO₃ stress at the germination stage did 4X materials show significantly higher D values than 2X materials (ΔD=0.149±0.164, P=0.004), whereas no significant difference between 4X and 2X was observed under the other four conditions. Pooled analysis across the five conditions showed a significant negative correlation between ΔD and diploid tolerance D_2X (r=-0.601, P=1.15×10^-8), suggesting that the gain from tetraploidization tended to occur in genetic backgrounds with weaker diploid tolerance. After field yield correction, LXRC 2X, PPQ 4X, and L060 2X combined favorable comprehensive salt tolerance with good potential yield and stress yield. 【Conclusion】Salt-alkali tolerance in non-heading Chinese cabbage is jointly regulated by salt type, developmental stage, and genetic background, and tetraploidization does not consistently improve tolerance. A stepwise evaluation strategy integrating preliminary screening at the germination stage, rescreening at the seedling stage, and validation throughout the whole growth period under field conditions, together with yield correction, can improve both screening efficiency and the accuracy of breeding-oriented selection.

Bioactive Components in Different Tissues of Xiangshui Lemon Fruits in Dry and Humid Tropical Areas of Yunnan

ZHU YinXiao, ZHANG BiRong, YAN SuYun, SHI WenBin, LIU WeiJie, DUAN MinXian, CHENG YunJiang, ZHOU XianYan

Scientia Agricultura Sinica. 2026, 59(21):  4924-4936.  doi:10.3864/j.issn.0578-1752.2026.21.015

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【Objective】 To systematically investigate the differences in bioactive components in different tissues of Xiangshui lemon (Citrus medica) from dry and humid tropical areas in Yunnan, this study clarified the distribution patterns of bioactive ingredients across various tissues (flavedo, albedo, pulp, central axis, and segment membrane) of Xiangshui lemon from dry and humid tropical areas, so as to provide the theoretical references for the further development and utilization of bioactive components of Xiangshui lemon. 【Method】 In this study, Xiangshui lemon fruits were collected from the dry‑hot region of Weishan and the humid region of Ruili in Yunnan Province as experimental materials. Ultra‑performance liquid chromatography coupled with quadrupole time‑of‑ flight high‑resolution mass spectrometry (UPLC‑Q‑TOF‑HRMS) was adopted for sample detection. One‑way analysis of variance (ANOVA), principal component analysis (PCA) and orthogonal partial least‑squares discriminant analysis (OPLS‑DA) were used for comprehensive evaluation, so as to screen characteristic bioactive components that could distinguish different producing areas and tissues. 【Result】 A total of 31 bioactive components were identified in Xiangshui lemon fruits from the two regions, including 12 phenolic acids, 18 flavonoids, and 1 limonoid. The contents of all bioactive components in Xiangshui lemon from Weishan dry-hot region were higher than those from Ruili humid-hot region. In different fruit tissues, the content order of phenolic acids was: flavedo > albedo > pulp > central axis and segment membrane; the content order of flavonoids was: flavedo > pulp > central axis and segment membrane > albedo; the content order of limonin was: central axis and segment membrane > pulp > albedo > flavedo. Multivariate statistical analysis showed that the PCA model could effectively distinguish samples from the two producing regions. OPLS-DA was further performed on metabolic data of different tissues from the two regions. With VIP ≥ 2 as the screening threshold, 4, 3, 2 and 2 differential metabolites were identified in flavedo, albedo, pulp, central axis and segment membrane, respectively. Based on the threshold of VIP ≥ 2, eriocitrin and apigenin-C-pentoside-C-arabinoside isomer were screened as the characteristic differential substances of four tissues in Weishan dry-hot region, which were predominantly accumulated in central axis & segment membrane and flavedo, respectively, while eriocitrin was identified as the key differential metabolite across all four tissues in Ruili humid-hot region. 【Conclusion】 Benefiting from the unique climatic conditions of dry-hot river valley, the total content of bioactive components in Xiangshui lemon fruits from Weishan dry-hot region was significantly higher than that in Ruili humid-hot region, and vanillic acid was exclusively detected in Weishan dry-hot region. The distribution of bioactive components presented obvious tissue specificity: flavedo was the primary enrichment tissue for phenolic acids and flavonoids, while central axis and segment membrane were the main accumulation tissue of limonin.

Diversity Analysis and Comprehensive Evaluation of Agronomic Traits and Biochemical Components in 128 Tea Germplasm

YANG Chun, LIANG SiHui, WANG AnRan, GUO Yan, QIAO DaHe, CHEN Juan, MI XiaoZeng, LI Yan, LIN KaiQin, CHEN ZhengWu

Scientia Agricultura Sinica. 2026, 59(21):  4937-4956.  doi:10.3864/j.issn.0578-1752.2026.21.016

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【Objective】This study aimed to explore the utilization potential of preserved tea germplasm and breed new elite tea cultivars, and to provide a theoretical and practical references for the breeding of new tea varieties and efficient identification of tea germplasm in Guizhou Province. 【Method】A total of 128 tea germplasm preserved in the resource nursery were used as materials. 6 agronomic traits (including cold resistance, phenological stage, bud and leaf morphology, etc.) and 14 biochemical components (including catechins, alkaloids, theanine, etc.) were systematically determined. Comprehensive evaluation was conducted by combining genetic diversity analysis, correlation analysis, cluster analysis, principal component analysis (PCA), and grey relational analysis (GRA). 【Result】The variation coefficients of 20 trait indices of the 128 tea germplasm ranged from 13.33% to 114.10%, and the genetic diversity indices ranged from 0.92 to 2.08. The average variation coefficient (31.66%) and genetic diversity index (1.63) of agronomic traits were lower than those of biochemical traits (49.80%, 1.86). The length of one bud and three leaves, theogallin, caffeine, epigallocatechin gallate (EGCG), epicatechin gallate (ECG), and theanine contents showed normal distribution, while the kurtosis values of gallocatechin gallate (GCG) and 1,2,6-tri-O-galloyl-β-D-glucose (1,2,6-TGGP) exceeded 20, indicating that the contents of these two components were highly concentrated in the 128 tea germplasm. Correlation analysis showed that the frost injury index was significantly positively correlated with bud and leaf pubescence (P<0.05), and significantly or extremely significantly negatively correlated with bud and leaf color, theobromine, caffeine, and epicatechin (EC) (P<0.01; P<0.05). One-bud-one-leaf stage was significantly or extremely significantly positively correlated with length of one bud with three leaves, young shoot pubescence, caffeine and EGCG contents (P<0.01; P<0.05), and extremely significantly negatively correlated with theogallin, gallic acid, EC, ECG, and theanine contents. Cluster analysis divided the 128 germplasm into 7 clusters, agronomic traits including phenological stages and yield indicators, together with major biochemical components such as caffeine, EGCG and theanine, were the key characteristics for distinguishing germplasm of different groups. PCA extracted 7 principal components with a cumulative contribution rate of 69.35%. Biochemical traits such as EGCG, caffeine, epigallocatechin (EGC), and EC were key indicators affecting F comprehensive score. Grey relational analysis was carried out by constructing an ideal cultivar based on extra-early sprouting, strong cold resistance, and high theanine content. The weighted grey relational degrees between 128 germplasm and the ideal cultivar ranged from 0.51 to 0.73, Notably, GT-GY-05, HJY-F1-55, GT-AS-41, GT-LP-01, and JAL1 exhibited values exceeding 0.7. 【Conclusion】The 128 tea accessions possessed abundant genetic diversity. Overall, biochemical traits showed higher variation coefficients and genetic diversity indices than agronomic traits. Core components including caffeine, EGCG and ECG exhibited relatively high genetic stability, whereas rare secondary metabolites such as methylated catechins and theogallin showed abundant variation, granting them great potential for breeding elite germplasm with unique traits. GT-AS-41, with a high weighted grey relational degree of 0.71, is characterized by extra-early sprouting, highly cold resistance and relatively high theanine content, showing great potential for breeding new high-quality extra-early-sprouting tea cultivars.