The genetic basis for plant architecture traits in peanut (Arachis hypogaea L.) is poorly understood.This study characterized quantitative trait loci (QTLs) underlying peanut main stem height (MSH),first branch length (FBL) and branch number (BN),using a high-density genetic linkage map in a recombinant inbred line (RIL) population derived from Huayu28 and P76.The map consists of 2266 SNPs and 68 SSRs covering a genetic distance of 2586.37 cM.The average distance between adjacent markers was 2.25 cM.A positive correlation was found between MSH and BN (r =0.354),FBL (r=0.854).QTL analysis showed 18 additive QTLs (four MSH,five FBL,and nine BN) mapped to 10 chromosomes.While most QTLs were identified in only one environment,qMSHA01.1 for MSH,qFBLA01.2 for FBL,qBNB07.1 and qBNB07.2 for BN were in two environments.Besides,24 pairs of epistatic QTLs were identified for MSH,FBL,and BN;all of which accounted for phenotypic variation explained (PVE) less than 10％.These results provide a foundation for fine mapping and cloning of genes affecting plant architecture and the design of molecular breeding in peanut.%目前关于花生株型的遗传机制了解不深.本研究利用来源于花育28和P76杂交构建的重组自交系群体(RIL),构建高密度遗传连锁图谱,对控制花生主茎高(MSH)、第一侧枝长(FBL)和分枝数(BN)的数量性状位点(QTL)进行定位分析.该图谱包含2266个SNP和68个SSR,总遗传距离为2586.37 cM.相邻标记间平均间距为2.25 cM.研究发现MSH分别与BN(r=0.354)、FBL(r=0.854)高度相关.QTL分析检测到18个加性QTL位点(4个与MSH相关,5个与FBL相关,9个与BN相关),分布于10个染色体.大多数QTL位点只在一个环境下检测到,其中主茎高相关位点qMSHA01.1,第一侧枝长相关位点qFBLA 01.2,分枝数相关位点qBNB07.1和qBNB07.2在两个环境下均能检测到.另外,针对MSH、FBL、BN,共有24对上位性QTL被检测到,表型变异解释率均低于10％.以上结果将为花生株型相关基因的图位克隆和分子标记设计育种提供重要的基础.
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