Plant & Animal Genomes XIV Conference

January 14-18, 2006
Town & Country Convention Center
San Diego, CA

DNA Markers Linked To The Grain Texture Locus In Diploid Wheat

Lingrang Kong¹ , Marcos Bonafede² , Jorge Dubcovsky² , Herbert Ohm¹

¹  Department of Agronomy, Purdue University, 915 W. State St., West Lafayette, IN 47907-2054, USA

²  Department of Agronomy and Range Science, University of California, Davis, CA 95616-8515, USA

Grain texture (degree of hardness) is an important determinant of wheat (Triticum aestivum) flour milling and baking qualities. It was recently shown that the incorporation of additional active copies of Pina-A^m1 and Pinb-A^m1 from diploid Triticum monococcum (A^m genome) results in softer kernels. We developed sequence-tagged-site (STS) markers for T. monococcum puroindoline a (Pina-A^m1), puroindoline b (Pinb-A^m1) conferring soft-textured grain, and for grain softness related protein (Gsp-A^m1), as well as BGGP (Beta-1-3-galactosyl-O-glycosyl-glycoprotein) linked to Gsp (3.4 kb) at the Ha locus. The STS markers were subsequently confirmed by their presence/absence in Chinese Spring (C.S.) deletion lines. Grain texture values were determined by Single Kernel Characterization System (SKCS) in 70 puroindoline lines from CS-5A^m × CS, and results were consistent with DNA marker data. DNA marker screening results in the segregation population derived from C.S. and C.S.-5A^m indicated the co-dominant marker for BGGP is closely associated with the STS markers of Pina-A^m1, Pinb-A^m1 and Gsp-A^m1.