Identification of QTL Underlying Seed Micronutrients Accumulation in ‘MD 96-5722’ by ‘Spencer’ Recombinant Inbred Lines of Soybean

Abstract

Genetic mapping of quantitative trait loci (QTL) associated with seed nutrition levels is almost non-existent. The objective of this study was to identify QTLs associated with seed micronutrients (iron, Fe; zinc, Zn; bororn, B; manganese, Mn; and copper, Cu) accumulation (concentration) in a population of 92 F5:7 recombinant inbred lines (RILs) that derived from a cross between MD 96-5722 (MD) and ‘Spencer’. For this purpose, a genetic linkage map based on 5,376 Single Nucleotide Polymorphism (SNP) markers was constructed using the Illumina Infinium SoySNP6K BeadChip array. The RILs were genotyped using 537 polymorphic, reliably segregating SNP markers. A total of 23 QTLs for micronutrients Fe, Zn, B, Mn, and Cu have been identified and mapped on eight linkage groups (LGs) of the soybean genome. Five QTLs were detected for Fe (qIRO001- qIRO005) on LGs N, A1, K, J, and G. Seven QTLs for Zn (qZIN001-qZIN007) on LGs D1a (Chr 1), N (Chr 3), F (Chr 5), B2 (Chr 14), J (Chr 16), A1 (Chr 5), and K (Chr 9). Two QTLs for B (qBOR001 and qBOR002) were detected on LGs N and A1. Four QTLs were detected for Mn (qMAN001-qMAN004) on LGs N, A1, K, and J, and five QTLs were detected for Cu (qCOP001- qCOP005) on LGs N, A1, K, J, and G). It was observed that the four QTLs for Zn, Cu, Fe, and Mn on LGs N (Chr 3), LG A1 (Chr 5), and LG J (Chr 16) were clustered in a similar region of the linkage groups, suggesting possible shared physiological and genetic mechanisms. The QTLs detected in this study are novel and will contribute to our understanding of the genetic basis of seed mineral nutrition. This research would allow breeders to efficiently select for higher seed nutritional qualities to meet the seed industry and human and livestock nutritional needs.