Genome-Wide Association Studies of Plant Architecture-Related Traits in the Chinese Soybean Mini Core Collection

Abstract

Plant architecture traits are closely related to plant biomass, lodging, and photosynthetic efficiency, which in turn affect soybean yield. In this study, we investigated a Chinese soybean mini core collection consisting of 224 germplasm accessions for four plant architecture-related traits (plant height (PH), number of nodes on main stem (NN), branch number (BN), and stem diameter (DI)) under three environments and conducted a genome-wide association study (GWAS) based on 1514 single nucleotide polymorphisms (SNPs). A total of 41 SNPs were found to be significantly associated with PH, NN, BN, and DI in two or more environments. Among these SNPs, 15 were located in regions in which plant architecture-related QTLs had been reported in previous studies, and 26 were new genetic loci. In addition, 18 potential candidate genes for plant architecture-related traits were obtained by predicting the genes in the interval of four large-effect markers (BARC-017097-02199, Map-2213, BARC-014639-01604, and Map-2223). This research will help to illuminate the genetic basis of soybean plant architecture-related traits and accelerate the process of plant architecture breeding by molecular marker-assisted selection in soybean.