| Authors: | Kato, S, Sayama, T, Fujii, K, Yumoto, S, Kono, Y, Hwang, T, Kikuchi, A, Takada, Y, Tanaka, Y, Shiraiwa, T, Ishimoto, M |
| Abstract: | Single seed weight (SSW) in soybean is a key determinant of both seed yield and the quality of soy food products, and it exhibits wide variation. SSW is under genetic control, but the molecular mechanisms of such con- trol remain unclear. We have now investigated quantitative trait loci (QTls) for SSW in soybean and have identi ed such a QTl that is stable across multiple environments and genetic backgrounds. Two populations of 225 and 250 recombinant inbred lines were developed from crosses between Japanese and US cultivars of soybean that differ in SSW by a factor of ~2, and these populations were grown in at least three different environments. A whole-genome panel comprising 304 simple sequence repeat (SSr) loci was applied to mapping in each population. We identi ed 15 signi cant QTls for SSW dispersed among 11 chromo- somes in the two populations. One QTl located between Sat_284 and Sat_292 on chromosome 17 was detected (3.6 < lOD < 14.1) in both populations grown in all envi- ronments. This QTl, tentatively designated qSw17-1, accounted for 9.4Ð20.9 % of phenotypic variation in SSW, with a dominant allele being associated with increased SSW. Given its substantial effect on SSW, qSw17-1 is an attractive target for positional cloning, and SSr markers closely associated with this locus may prove useful for marker-assisted selection for SSW control in soybean. |