Researchers at the University of Tennessee have investigated the genomic regions controlling amino acid composition in soybeans. Their studies have been directed at identifying genomic regions of the various soybean chromosomes that control essential and non-essential amino acids in soybean seed. A total of 101 F6-derived recombinant inbred lines were developed by crossing two high-protein germplasm lines. Significant differences (P>0.01) were found in recombinant inbred lines for various essential and non-essential amino acids in the soybean lines. While the variation in some amino acids were minimal; several essential amino acids (valine, leucine, phenylalanine, lysine, histidine and methionine) showed sufficient variation that indicates genetic gains may be possible through soybean breeding efforts. In this population, asparatic acid, glutamic acid, proline, valine, arginine, isoleucine, leucine, tyrosine, tryptophan and methionine have moderately high heritability estimates, whereas the remaining amino acids had low to medium estimates. Molecular analysis indicated that at least one quantitative trait loci was detected for each amino acid in this population. The researchers conclude that the molecular markers and quantitative traits loci identified in this project may provide soybean breeders new tools in their efforts to develop soybean germplasm lines with improved levels of essential amino acids that are important to the animal nutritionist.
Panthee, D.R. and co-workers. 2006. Genomic regions associated with amino acid composition in soybean. Molecular Breeding. 17: 79-89.