Author
XIANZHI, WANG - South Dakota State University | |
JIANG, GUO-LIANG - South Dakota State University | |
Song, Qijian | |
Cregan, Perry | |
Scott, Roy | |
ZHANG, JIAOPING - South Dakota State University | |
YEN, YANG - South Dakota State University | |
BROWN, MICHAEL - South Dakota State University |
Submitted to: Euphytica
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/23/2014 Publication Date: 8/5/2014 Citation: Xianzhi, W., Jiang, G., Song, Q., Cregan, P.B., Scott, R.A., Zhang, J., Yen, Y., Brown, M. 2014. Quantitative trait locus analysis of seed sulfur containing amino acids in two recombinant inbred line populations of soybean. Euphytica. DOI 10.1007/s10681-014-1223-0. Interpretive Summary: Soybean is a major source of plant protein for humans and livestock. The low level of sulfur containing amino acids (cysteine and methionine) in soybean protein is the main limitation of soybean meal as animal feed. The objectives of this study were to identify genetic factors associated with cysteine and methionine contents in soybean. The progeny derived from two soybean crosses were evaluated for the level of seed cysteine and methionine contents when grown in three different field trials. The results from the first set of progeny revealed that there were eight different chromosomal regions that contained genetic factors influencing cysteine and methionine contents in the seed. These eight regions were consistently detected in any individual environment and the average data over all three environments. Three of these regions were confirmed in a second set of progeny. A comparison with previous studies indicated that most of the chromosomal regions identified were also associated with total seed protein content. This information should be useful to soybean breeders for the improvement of protein and sulfur containing amino acids in soybean. Technical Abstract: Soybean (Glycine max (L.) Merr.) is a major source of plant protein for humans and livestock. Low levels of sulfur containing amino acids (cysteine and methionine) in soybean protein is the main limitation of soybean meal as animal food. The objectives of this study were to identify and validate QTLs associated with cysteine and methionine contents in two recombinant inbred line (RIL) populations, and to analyze the genetic effects of individual QTLs and QTL combinations in soybean. Both the mapping population of SD02-4-59 × A02-381100 and the validation population of SD02-911 × SD00-1501 were evaluated for cysteine and methionine contents in multiple environments. Correlation analysis indicated that there was a highly positive correlation between cysteine and methionine contents. Significant positive correlations were also observed between the sulfur containing amino acid contents and protein content. In the mapping population, eight QTLs for both cysteine and methionine contents were consistently detected in any individual environment and the average data over all three environments. Three of these QTLs were confirmed in the validation population. A comparison with previous studies indicated that most of the genomic regions linked to the QTLs for the sulfur containing amino acids were also associated with protein content. Cumulative effects of multiple QTLs for the traits were significant in both the populations. This information should be useful for the improvement of protein and amino acids in soybean. |