摘要
【目的】为明确猕猴桃细菌性溃疡病的抗性代谢机制,基于代谢组学技术对病菌侵染不同时间的山梨与中华猕猴桃杂交种质(抗病种质E2545和感病种质E674)进行代谢物定性定量分析,旨在筛选与猕猴桃抗细菌性溃疡病相关的差异代谢物,并明确其参与的植物抗病代谢途径,为猕猴桃抗溃疡病育种及抗性机制解析提供理论支撑。【方法】采用离体枝条接种法对抗感种质进行病原菌接种,并于接种前及接种后3 d、7 d、14 d四个时期,对接种点上下1 cm处的枝条木质化组织取样。进一步采用高效液相色谱-串联质谱法(LCMS/MS)及非靶向代谢组学检测抗感种质的差异代谢物。【结果】抗感猕猴桃种质间差异代谢物种类主要为苯和取代衍生物、香豆素及其衍生物、异戊烯醇脂类、羧酸及其衍生物等。87种差异代谢物在抗病材料中的含量始终高于感病材料,推测这些代谢物可能在猕猴桃抵御溃疡病菌侵染机制中发挥重要作用。进一步筛选出阿司匹林(aspirin)、甘草酸(liquoric acid)、pestalactam B、缬草素(valtratum)4种可能具有重要应用潜力的防御相关代谢物。苯丙烷类生物合成通路及苯丙烷代谢通路可能是猕猴桃响应溃疡病菌侵染的关键代谢途径。【结论】本研究对溃疡病菌侵染不同时间的山梨与中华猕猴桃杂交群体的抗感种质进行了代谢物定性定量分析,从代谢角度阐明了猕猴桃抗感种质响应溃疡病菌侵染的分子机制,为快速筛选与挖掘抗病种质奠定了理论基础,同时为研发新型生防药剂提供了理论依据。
【Objective】Actinidia Lindl.,a deciduous perennial liana genus endemic to China,is recognized globally as a functional fruit crop owing to its unique organoleptic characteristics,exceptional nutritional profile(notably distinguished as the ascorbate hyperaccumulator within Rosidae clade),and pharmacological properties.The Chinese kiwifruit industry has undergone remarkable expansion,with cultivation areas reaching 300000 hectares and annual production achieving 4.346 million metric tons by 2024.This growth has significantly contributed to regional economic development,poverty alleviation initiatives,and agroecosystem rehabilitation.Pseudomonas syringae pv.actinidiae(Psa),a phytopathogen with rapid dissemination capacity and high virulence,poses severe threats to global kiwifruit production,causing epidemic canker outbreaks.Identifying excellent disease-resistant germplasms,elucidating the underlying mechanisms of resistance formation,and developing resistant cultivars are crucial approaches to addressing the occurrence of canker.Plant metabolite alterations provide insights into metabolic states,gene expression,and protein function.By conducting metabolomics research on the resistant genotype E2545 and susceptible genotype E674 at different infection time points,we can identify differential metabolites,determine associated metabolic pathways,and reveal their roles in biological processes.This study offers a metabolic perspective on the molecular mechanisms underlying the response of kiwifruit materials with differential resistance to Psa infection.【Methods】In vitro stem inoculation assays were conducted on Psa-resistant(E2545)and susceptible(E674)kiwifruit genotypes under controlled phytosanitary conditions.Longitudinal sections(1 cm)of xylem-differentiated tissues were sampled proximal and distal from the inoculation site at defined intervals(0,3,7,and 14 days post-inoculation,dpi).Untargeted metabolomic profiling was performed using the ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(UHPLC-QTOF-MS/MS).Raw metabolite data was acquired using MassLynx V4.2.Data processing including peak extraction and alignment was performed using Progenesis QI.Metabolite identification was achieved against a self-built database(BMK)using MS/MS data,with quantification via multiple reaction monitoring on a triple quadrupole mass spectrometer.Differential metabolites were screened using thresholds of variable importance in projection(VIP)≥1,P-value<0.05,and log2|FC|≥1.【Results】Comparative metabolomic profiling revealed distinct clustering of specialized metabolites between P.syringae pv.actinidiae(Psa)-resistant and susceptible Actinidia genotypes.Differential metabolites were predominantly categorized as benzene and substituted derivatives,coumarins and derivatives,prenol lipids,carboxylic acids and derivatives.Quantitative analysis demonstrated significant accumulation of 87 defense-related metabolites in resistant germplasm,including key phytoalexins and signaling molecules linked to systemic acquired resistance.Four metabolites exhibiting dual antimicrobial and immune-priming activities were prioritized:aspirin,liquoric acid,pestalactam B,and valtratum.KEGG pathway enrichment analysis revealed significant activation of phenylpropanoid biosynthesis and phenylpropanoid metabolism,indicating their critical roles in kiwifruit defense against Psa infection.【Conclusion】This study conducted comparative metabolomic profiling of resistant and susceptible germplasms in Actinidia rufa and Actinidia chinensis var.chinensis subjected to varying P.syringae pv.actinidiae(Psa)infection periods.Building on these findings,further in-depth research on the key differential metabolites between resistant and susceptible kiwifruit germplasms could elucidate the disease resistance mechanisms of germplasms,providing a theoretical basis for screening novel kiwifruit germplasms resistant to bacterial canker.Additionally,antimicrobial activity assays and field trials should be conducted to validate the antibacterial properties of these metabolites,facilitating the development of innovative biocontrol agents.This integrated approach would advance both the theoretical framework and practical applications in kiwifruit disease resistance breeding and sustainable disease management.
作者
贺迪
朱佳慧
潘慧
李文艺
杨洁
黄跃
钟彩虹
刘普
李黎
HE Di;ZHU Jiahui;PAN Hui;LI Wenyi;YANG Jie;HUANG Yue;ZHONG Caihong;LIU Pu;LI Li(Wuhan Botanical Garden,Chinese Academy of Sciences/State Key Laboratory of Plant Diversity and Specialty Crops,Wuhan 430074,Hubei,China;School of Horticulture,Anhui Agricultural University/Anhui Province Key Laboratory of Horticultural Crop Quality Biology,Hefei 230036,Anhui,China)
出处
《果树学报》
北大核心
2026年第1期13-25,共13页
Journal of Fruit Science
基金
贵州省科技重大专项项目(黔科合重大专项字[2024]026)
国家重点研发项目(2022YFD1400200)
湖北省第四批现代农业产业技术体系专项资金资助(2024HBSTX4-08)
湖北省支持种业高质量发展资金农业种质资源保护利用课题(HBZY2023A001-05)
国家现代农业产业技术体系(CARS-26)
植物基因组学国家重点实验室开放课题(SKLPG2016A-18)
中国科学院定点帮扶项目(KCXFZJ-DDBF-202401)。
关键词
猕猴桃
溃疡病
非靶向代谢组
KEGG
抗病机制
Kiwifruit
Bacterial canker
Non-targeted metabolomic
KEGG
Resistance mechanism
