Cowpea (Vigna unguiculate (L.) Walp.) is a worldwide important multifunctional legume crop for food grain, vegetable, fodder, and cover crop. Nevertheless, only limited research has been conducted on agronomic traits. Here, we report quantitative trait locus (QTL) analysis of the days to flowering (DTF) and plant height (PH) using a dense SNP linkage map recently developed from a recombinant inbred line (RIL) population derived from a cross between Golden Eye Cream and IT98K-476-8. The population was phenotyped for DTF and PH through field and greenhouse trials under two environments. The QTLs controlling these traits were mapped using multiple-environment combined and individual trial phenotypic data. The combined data analysis identified one major QTL (qDTF9.1) for DTF, and one major QTL (qPH9.1) and a minor QTL (qPH4.1) for PH. qDTF9.1 and qPH9.1 were adjacent to each other on Chromosome 9 and each explained 29.3% and 29.5% of the phenotypic variation (PVE), respectively. The individual trial data analysis identified a minor QTL (qDTF2.1) on Chromosome 2 for DTF and two minor QTLs (qPH4.1 and qPH4.2) on Chromosome 4 for PH, while the major QTLs, qDTF9.1 and qPH9.1, were consistently identified in all trials conducted. Epistasis analysis revealed that qDTF9.1 interacted with one locus on Chromosome 4, contributed 50% of the PVE, and qPH9.1 interacted with one locus on each of Chromosomes 4 and 6, contributing 30% and 23% of the PVE, respectively, suggesting that epistasis plays an important role in the trait performance. These results, therefore, provide a deeper understanding of the genetic architecture of plant DTF and PH, and molecular tools necessary for cloning the genes and for enhanced cowpea breeding.

pea豆（Vigna unguiculate（L.）Walp。）是一种世界范围内重要的多功能豆类作物，用于粮食，蔬菜，饲料和覆盖作物。然而，关于农艺性状仅进行了有限的研究。在这里，我们报告了使用最近从重组自交系（RIL）群体开发的致密SNP连锁图对开花天数（DTF）和植物高度（PH）进行定量性状基因座（QTL）分析，该图谱来自Golden Eye Cream和IT98K-476-8。通过在两种环境下的田间试验和温室试验对种群的DTF和PH进行了表型分析。使用多环境组合和单个试验表型数据对控制这些性状的QTL进行了定位。组合数据分析确定了一个主要的QTL（qDTF9.1）用于DTF，一个主要QTL（qPH9.1）和一个次要QTL（qPH4.1）用于PH。qDTF9.1和qPH9.1在9号染色体上彼此相邻，分别解释了29.3％和29.5％的表型变异（PVE）。单独的试验数据分析确定了DTF第2号染色体的一个小QTL（qDTF2.1）和PH 4号染色体的两个小QTL（qPH4.1和qPH4.2），而主要QTL qDTF9.1和qPH9.1，在所有进行的试验中均得到一致确认。上位性分析显示，qDTF9.1与第4号染色体上的一个基因座相互作用，贡献了50％的PVE，并且qPH9.1与4号和6号染色体上的一个基因座相互作用，分别贡献了30％和23％的PVE，表明上位性在性状表现中起重要作用。因此，这些结果为植物DTF和PH的遗传结构以及克隆基因和增强cow豆育种所需的分子工具提供了更深入的了解。