PCR-based markers for identification of HMW-GS at Glu-B1x loci in common wheat

The bread wheat elasticity, which is very important for bread-making quality, is largely determined by the composition of high-molecular-weight glutenin subunits (HMW-GS). The HMW-GS encoded by Glu-B1 loci are highly polymorphic and the combinations 17+18 and 14+15 are good for bread making. Thus it is very important to identify the alleles at Glu-B1 loci for wheat quality improvement. In this study, the five common HMW-GS types encoded by Glu-B1x locus carried by 18 Chinese bread wheat cultivars (or lines) were analyzed by SDS-PAGE. Two pairs of PCR primers which could distinguish the Glu-Blx alleles of the five common HMW-GS types were designed based on the Glu-B1x gene sequences (Reddy and Appels, 1993; Genbank accession: X13927; Genbank accession:AY367771). 22 recombinant inbred lines (RILs) derived from Jing711 (contains 17 subunit on Glu-B1x) and Pm97034 (contains 14 subunit on Glu-B1x) were used to validate the accuracy of the primers, which showed that the two specific markers could be used together to distinguish alleles at Glu-B1x locus and accelerate wheat quality breeding by marker assisted selection.