Evaluation of Wild Segments Related to Growth Period Traits Using a Modified Wild Soybean (Glycine Soja Sieb. Et Zucc.) Chromosome Segment Substitution Line Population

Abstract Soybean seeds contain high levels of oil and protein providing 69% and 57% of dietary protein and oil respectively. Although many quantitative trait loci for 100-seed weight (100SW), protein content (PRC) and oil content (OIC) have been reported, their genetic controls in soybeans remain unclear. The QTL–allele constitution of three traits in the Sichuan and Chongqing eco-regions population (SCLBP) was studied using a representative sample composed of 228 accessions tested under four environments and analyzed based on 135 SSR and 107081 valid SNP (single nucleotide polymorphism linkage) markers. The varied range of 100SW, PRC and OIC of SCLBP were 4.82-33.35, 36.47-49.75 and 14.68-21.77 among accessions, respectively. The heritability ( h 2 ) and genetic coefficient of variation ( GCV ) of three traits were high. As a result, 26, 33 and 31 QTLs were found by SSR to be associated with 100SW, PRC and OIC, respectively. The allele of Sat_260 for 100SW was detected in 4 environments. In addition, 28, 198 and 250 loci for 100SW, PRC and OIC were found by SNP using mixed linear model (MLM), respectively. Further SNP haplotype analysis showed that 13, 35 and 60 blocks for 100SW, RPC and OIC were found. The block of Gm11_9895764-9917646 for 100SW was simultaneously detected in four environments. Among these QTLs, 1, 5, and 7 for 100SW, PRC and OIC were found by two methods of SSR and SNP at the same time. A majority of these QTLs overlapped with the previously reported loci. However, 9, 11 and 9 loci for 100SW, PRC and OIC using SSR and 3, 5 and 8 for 100SW, PRC and OIC haven’t been reported using SNP in the study, respectively. Moreover, the genes of Glyma.11g130800, Glyma.13g217000 and Glyma.08g122600 were considered to be the most likely genes controlling 100SW, PRC and OIC, respectively. Our findings provide evidence for mixed major plus polygenes inheritance for three traits and an extended understanding of their genetic architecture for molecular dissection and breeding utilization in soybeans.