猕猴桃砧木抗旱性评价及转录组分析  

Analysis of drought resistance of kiwifruit rootstocks based on physiolo-gy and transcriptome

作　　者：周康宇 何成勇 徐子鸿 王玲利 赵科 宋海岩[1] 刘普[2] 涂美艳[1] ZHOU Kangyu;HE Chengyong;XU Zihong;WANG Lingli;ZHAO Ke;SONG Haiyan;LIU Pu;TU Meiyan(Institute of Horticulture,Sichuan Academy of Agricultural Sciences/Key Laboratory of Horticultural Crop Biology and Germplasm Cre-ation in Southwest China,Ministry of Agriculture and Rural Affairs,Chengdu 610066,Sichuan,China;School of Horticulture,Anhui Agricultural University,Hefei 230036,Anhui,China)

机构地区：[1]四川省农业科学院园艺研究所·农业农村部西南地区园艺作物生物学与种质创制重点实验室,成都610066 [2]安徽农业大学园艺学院,合肥230036

出　　处：《果树学报》2024年第11期2300-2311,共12页Journal of Fruit Science

基　　金：四川省科技计划项目(2022YFYZ0003);四川省“十四五”果树育种攻关(2021YFYZ0023-01);国家现代农业产业技术体系四川创新团队(SCCXTD-2024-4);国家柑橘产业技术体系猕猴桃成都综合试验站(CARS-26)。

摘　　要：[目的]探讨不同猕猴桃砧木在干旱胁迫条件下的生理和分子响应机制。[方法]利用25%PEG-6000模拟干旱胁迫,对4种猕猴桃材料Bruno、XD-GZ-7、XD-RZ-1和DJY-DE-1进行干旱处理,通过植株表型观测和生理指标测定,进一步利用转录组测序发掘关键差异表达基因。[结果]Bruno在干旱胁迫下最早表现出明显的叶片失水和植株萎蔫现象,旱害指数为87%,显著高于其他材料;而DJY-DE-1则表现出较强的抗旱性,叶片在胁迫后第8天出现轻微下垂现象,旱害指数为33%,显著低于其他材料。转录组分析揭示了两份材料在各时期均显示出大量的差异表达基因,GO富集分析显示这些基因主要涉及细胞过程、代谢过程等生物过程,细胞和细胞膜等细胞组分,以及结合、催化活性等分子功能。KEGG通路富集分析显示差异基因主要参与信号转导、代谢通路、蛋白质折叠和分类等关键生物过程。利用WGCNA分析进一步筛选出了4个可能参与根系干旱响应的关键差异表达基因。[结论]综合生理指标和转录组学数据,深入分析了猕猴桃不同砧木对干旱胁迫的响应机制,为未来改良作物抗旱性提供了理论基础和试验依据。【Objective】This study aimed to investigate the physiological and molecular mechanisms of drought tolerance of different kiwifruit rootstock materials,with the goal of providing a foundation for future breeding and genetic improvement efforts to enhance drought resistance in kiwifruit.【Methods】Four kiwifruit cultivars with varying degrees of drought tolerance were selected:Bruno(Actinidia deli-ciosa),XD-GZ-7(A.polygama),XD-RZ-1(A.eriantha)and DJY-DE-1(A.valvata).These cultivars were chosen based on previous observations on their drought tolerance and represent diverse genotypes from the collected germplasm.Drought stress was simulated using 25%PEG-6000,applied at five times(0,2,4,6 and 8 days).Phenotypic assessments included observations on leaf wilting,plant dehy-dration and overall drought response.Physiological parameters,such as malondialdehyde(MDA),pro-line(Pro),hydrogen peroxide(H2O2),superoxide dismutase(SOD)and catalase(CAT)were measured.In addition,transcriptome sequencing of the roots of DJY-DE-1 and Bruno at 0,4 and 8 days was per-formed to identify differentially expressed genes(DEGs).Then,the Weighted Gene Co-expression Net-work Analysis(WGCNA)algorithm was employed for module construction.The core steps of this algo-rithm involved calculating the similarity between genes to construct a gene clustering tree,in which each branch represented an independent module.To more precisely delineate these modules,a dynamic tree cutting method was utilized to slice the gene clustering tree.To further quantify the co-expression similarity among the modules,the module eigengenes(MEs)for each module were calculated,and these eigengenes were then used to merge modules that exhibited similarity.Validation of key genes was conducted using quantitative real-time PCR(qRT-PCR).【Results】Significant differences in drought responses were observed between the materials.Bruno exhibited early and severe symptoms of drought stress,with noticeable leaf wilting by day 4(S3),and widespread dehydration by day 8,with a dr

关 键 词：猕猴桃 干旱胁迫 生理机制 转录组 

分 类 号：S663.4[农业科学—果树学]