Wednesday, 9 November 2005
3

This presentation is part of: Markers, Maps, QTLs

Epistatic Gene Interaction in QTLs of Soybean Seed Characters.

Johann Vollmann, Apanee Pokeprasert, Gertraud Stift, and Tamas Lelley.

Epistasis is considered to be an important feature of quantitative performance in self-pollinated (homozygous) crop species. A bi-parental segregating population between two early maturity soybean parents (Ma.Belle x Proto) consisting of 82 F2-families had initially been analysed with a large number of polymorphic SSR markers, and QTL effects in seed characters had been reported. In the F6 generation, 5 to 8 different lines were derived from each F2 family, and a total of 530 homozygous lines was evaluated phenotypically in four environments and re-genotyped using 29 SSR markers associated with QTLs in the initial analysis. Using analysis of variance for testing of associations, about 10 QTLs were found for 1000-seed weight and several others for seed protein and oil content, respectively. The presence of 1000-seed weight QTLs on soybean linkage group O was confirmed. Two-way analysis of variance revealed a number of highly significant interactions between markers, indicating epistatic gene interaction. Significant interactions have been found both between QTL regions as well as between regions without a significant main effect. Similar to QTL main effects, some epistatic QTL effects were stable across environments, whereas for others a significant epistasis x environment interaction effect was present. In 1000-seed weight, the phenotypic effect of particular epistatic QTLs was clearly larger than the effect of the main QTLs found. The present results suggest, that epistatic gene interaction has a considerable impact on the genetics of 1000-seed weight of soybean.

See more of Markers, Maps, QTLs
See more of C07 Genomics, Molecular Genetics & Biotechnology

See more of The ASA-CSSA-SSSA International Annual Meetings (November 6-10, 2005)