2008 Joint Annual Meeting (5-9 Oct. 2008): Efficiency of Marker Assisted Selection for Soybean Seed Sucrose Content.

Soybean seed sucrose content ranges from 5 to 8%, and is quantitatively inherited. At least 8 genomic regions were associated with soybean sucrose seed content. Marker assisted selection for quantitative traits is desirable in order to maximize breeding efficiency; however, the markers linked to the quantitative trait loci (QTL) for sucrose content are population-specific and environment dependent. The objective of this study is, therefore, to validate marker-assisted selection for sucrose content using single sequence repeat (SSR) markers associated to previously reported QTLs. A high-sucrose parent was crossed with a conventional high-yield soybean cultivar, and the segregating population was advanced via single seed descent to the F3 generation, when lines were derived from single plants. The lines were grown in 2 environments in 2007 and 3 environments in 2008 for DNA extraction and sucrose analysis. Sucrose content was determined using anion-exchange chromatography (HPLC) coupled with an electrochemical detector. Molecular makers flanking reported QTLs were selected and confirmed to be polymorphic. Efficiency of marker-assisted selection will be assessed by contrasting the base-population mean sucrose content with the sucrose content of the individuals with and without combinations of alleles from the high-sucrose parent.