Mapping of the heading date gene HdAey2280 in Aegilops tauschii

An optimum heading date is essential for sustainable crop productivity and ensuring high yields. In the present study, F2:3 populations were generated by crossing an early-heading accession, Y2280, with a late-heading accession, Y2282. The heading dates of the F2 and F3 populations were investigated in a field study. Using publicly available simple sequence repeat (SSR) markers, the early heading date gene HdAey2280 was mapped onto Aegilops tauschii chromosome 7DS between the flanking markers wmc438 and barc126 at distances of 15 and 9.1 cM, respectively. Further analysis indicated that HdAey2280 is a novel heading date gene. New SSR markers were developed based on the Ae. tauschii draft genome sequence, resulting in four new markers that were linked to the heading date gene HdAey2280. The closest distance of these markers was 1.9 cM away from the gene. The results collected in this study will serve as a framework for map-based cloning and marker-assisted selection in wheat breeding programs in the future.