Identifying Genomic Regions Conferring Morphological and Yield-related Traits in Soybean Based On A Four-way Recombinant Inbred Line Population

Improvement of seed yield of soybean(Glycine max(L.) Merr.) is generally achieved by combining morphological and yield-related traits, such as plant height(PH), node number on main stem(NN), pod number per plant(NP), seed number per plant(NS), 100-seed weight(HSW) and seed weight per plant(SWPP). Identifying quantitative trait loci(QTLs) for morphological and yield-related traits is therefore important for breeding. In this study, a four-way recombinant inbred line population comprising 160 lines derived from the cross(Kenfeng14×Kenfeng15)×(Heinong48×Kenfeng19) was planted in five different environments and morphological and yield-related trait data were used to identify QTLs by the inclusive composite interval mapping method. Totally 38 QTLs for PH, 40 QTLs for NN, 26 QTLs for NP, 10 QTLs for NS, 26 QTLs for HSW and 49 QTLs for SWPP were detected in 125 genomic regions. Single QTLs explained 2.17%-14.60%, 2.00%-10.04%, 2.37%-9.77%, 2.62%-8.61%, 0.47%-6.51% and 0.14%-12.39% of the phenotypic variation for PH, NN, NP, NS, HSW and SWPP, respectively. Among these 125 genomic regions, 120 were newly associated with morphological and yield-related traits. The results would facilitate the molecular breeding of morphological and yield-related traits in soybean.