Mapping of QTL Associated with Seed Amino Acids Content in “MD96-5722” by “Spencer” RIL Population of Soybean Using SNP Markers

Limited information is available on the genetic analysis of amino acid composition in soybean seeds. Previously, quantitative trait loci (QTLs) for seed isoflavones, protein, oil, and fatty acids were identified in the "MD96-5722" by "Spencer" and other RIL populations. There were wide variations for these seed constituents among the RIL populations. Therefore, the objective of this study was to identify QTLs controlling different amino acids content in soybean seeds. To achieve this objective, ninety-two F5:7 recombinant inbred lines (RIL), developed from a cross of MD96- 5722 and Spencer, using a total 5376 Single Nucleotide Polymorphism (SNPs) markers, were used. The RILs were genotyped by using 537 polymorphic, reliably segregating SNP markers, developed from the Illumina Infinium SoySNP6K BeadChip array. A total of 13 QTLs were identified with three QTLs for threonine on the linkage group (LG) A1, C2, and B2. Two QTLs were identified for each of the amino acids proline on LG D1a and B2, serine on LG A1 and C2, tryptophan on LG K and G, and cysteine on LG A1 and K. One QTL was identified for arginine on LG N and histidine on LG J. The new QTLs findings for seed amino acid will facilitate the development of soybean cultivars with higher protein and amino acid quality to help meet the industry and consumer needs. * Corresponding author.