豇豆SNP高密度遗传图谱构建及重要农艺性状QTL定位

Construction of SNP high-density genetic map and QTL analysis of agronomic traits in cowpea(Vigna unguiculata(L.)Walp.)

为促进豇豆种质资源的高效利用和新基因发掘,本研究基于豇豆F2群体,利用重测序技术构建了包含2984个bin标记(142,146个SNP)的遗传连锁图谱。该图谱共11个连锁群,总长1333.48 cM,平均图距0.45 cM。不同连锁群的长度从84.63~183.15 cM不等,平均图距从0.27 cM至0.89 cM不等。根据F_(2)、F_(3)的表型调查,利用该图谱共检测到15个QTL,分别与百粒重、花色、荚长、荚形、荚质、籽粒颜色等14个性状相关。其中荚质、荚长、主茎分枝数等分别检测到1个主效QTL区间,其余性状检测到多个QTL区间。通过对区间内的基因注释分析,分别确定了与荚长、单株荚数、籽粒颜色构成等性状相关的候选基因。本研究中QTL分析结果将为豇豆属重要性状的标记辅助选择奠定基础,而候选基因筛选则有助于深入解析这些性状的遗传机理,提高豇豆分子遗传学研究水平。

To promote efficient utilization of cowpea germplasm resources and new gene discovery,a genetic linkage map containing 2984 Bin markers(142,146 SNPs)was constructed based on cowpea F_(2) population using re-sequencing technology.The map consisted of 11 linkage groups with a total length of 1333.48 cM and an average map spacing of 0.45 cM.The length of different linkage groups ranged from 84.63 cM to 183.15 cM,and the average plot distance ranged from 0.27 cM to 0.89 cM.A total of 15 QTLs were detected to be associated with 14 traits,including 100-grain weight,flower color,pod length,pod shape,pod shape and grain color,respectively.One major QTL region was detected for pod type,pod length,and number of branches per main stem,and multiple QTLs regions were detected for other traits.Candidate genes related to pod length,number of pods per plant,and single/double color of grains were further identified by gene annotation analysis in the interval.The results of QTL analysis in this study will lay a foundation for marker-assisted selection of important traits of cowpea,and candidate gene screening will help to further analyze the genetic mechanism of these traits and improve the level of molecular genetics research of cowpea.