QTL Mapping for Major Agronomic Traits across Two Years in Soybean (Glycine max L. Merr.)

The agronomic traits, such as days to flowering and maturity, plant height, 100-seed weight and seed filling period, are quantitatively inherited and important characters in soybean (Glycine max L. Merr.). A total of 126 F5 recombinant inbred lines (RILs) developed from the cross of PI 171451×Hwaeomputkong were used to identify quantitative trait loci (QTLs) for days to flowering (FD), days to maturity (MD), plant height (PH), 100-seed weight (SW), number of branches (NB) and seed filling period (FP). A total of 136 simple sequence repeat (SSR) markers segregated in a RIL population were distributed over 20 linkage groups (LGs), covering 1073.9 cM of the soybean genome with the average distance between adjacent markers of 7.9 cM. Five independent QTLs were identified for FD, three for MD, two for PH, three for SW, one for NB and one for FP. Of these, three QTLs were related to more than two traits of FD, MD, PH, NB and FP and mapped near the same positions on LGs H and O. Thus, these traits could be correlated with biologically controlled major QTLs in this soybean RIL population.