基于连锁和关联分析剖析甜瓜幼苗耐冷性的遗传基础

项目名称： 基于连锁和关联分析剖析甜瓜幼苗耐冷性的遗传基础

项目编号： No.31672147

项目类型： 面上项目

立项/批准年度： 2017

项目学科： 农业科学

项目作者： 胡建斌

作者单位： 河南农业大学

项目金额： 25万元

中文摘要： 甜瓜是典型的非冷驯化植物，对低温敏感，生产中育苗及定植初期常常遭受低温冷害的侵袭。深入理解甜瓜耐冷性的遗传基础，挖掘耐冷相关基因，培育强耐冷的品种，是克服苗期冷害、生产优质高产甜瓜的有效途径。本实验室前期构建了一个甜瓜核心种质，其耐冷性变异广泛，并从中鉴定了一个强耐冷的薄皮种质“蛤蟆酥-5”。进一步的研究表明，该种质中存在耐冷的主基因。本研究拟以耐冷和冷敏的材料构建F2:3群体，同时以甜瓜核心及附加种质为关联群体，采用高通量RAD-seq技术进行基因分型，联合连锁和关联分析方法精细定位幼苗耐冷性主效QTL，深入挖掘影响表型变异的基因和功能位点，并开发适用性分子标记。研究结果预期能帮助明确甜瓜幼苗耐冷性变异的遗传基础，为甜瓜分子育种积累材料平台、技术平台和基因资源。

中文关键词： 甜瓜；耐冷性；连锁分析；关联分析；遗传基础

英文摘要： Melon, a typical non-cold-acclimation plant, is sensitive to low temperature. At the stage of seedling raising and the primary stage of transplantation into the field, the melon seedlings are often suffered from chilling injury. Deep understanding of the genetic basis of chilling resistance in melon, discovery of the chilling-resistance genes using modern molecular biotechnologies, and development of new cultivars with improved chilling resistance, are useful approaches to overcome the chilling injury at seedling stage and produce high-yield and -quality melon fruits. Previously, our laboratory developed a melon core collection, which revealed a wide variation in chilling resistance, and from them, we identified a thin-skin accession “Hamasu-5” with a strong chilling resistance. The further research showed that “Hamasu-5” contained the major genes conferring chilling resistance. The F2:3 family population, which derived from a cross between chilling-resistance and chilling-sensitive accessions, and a core collection with additional germplasms are used as materials in the present research. The reduced-representation genome sequencing (RAD-seq) technology is used for genotyping of the melon accessions. The linkage and association analysis are applied to fine mapping of the major QTLs for chilling-resistance in melon seedlings and further explore the genes and function loci that affect the phenotypic variation. Also, the practicable molecular markers will be developed from the QTLs, which will act as a useful tool in molecular breeding. Our results are expected to enhance our understanding of the genetic basis of chilling resistance variation in melon seedlings and construct the platform of materials, technologies and gene resources for melon molecular breeding.

英文关键词： melon;chilling resistance;linkage analysis;association analysis;genetic basis