Allele-specific PCR Markers for Distinguishing High Molecular Weight Glutenin Subunit <i>Dtx5</i> of <i>Aegilops tauschii</i> from <i>Dx5</i> of Common Wheat

High molecular weight (HMW) glutenin, one of the important storage proteins of wheat, mainly confers end-use quality of wheat grain. Among the loci of HMW-GS, the locus D1 determines the breaking quality of bread wheat dough mostly. Synthetic hexaploid wheat (SHW) inherits vast genetic diversity in the D genome of Aegilops tauschii and has gradually been used as a bridge-tool for wheat improvement. Therefore, more and more HMW-GS subunit types of Ae. tauschii have been introgressed into the common wheat with irresistible application of SHW in wheat breeding. However, the traditional SDS-PAGE couldn’t distinguish Dtx5 of Ae. tauschii from Dx5 of common wheat. In this study, we developed two AS-PCR markers based on three SNPs in the HMW-GS D1 sequences of Ae. tauschii and common wheat. The sharp and stable fragments amplified by designed AS-PCR primers indicated their availability and convenience in Dtx5 and Dx5 identification. And Dx5 of common wheat obtained the amplified fragments by AS-PCR primers, while no fragment was amplified for Dtx5 of Ae. tauschii. And the amplified results were consistent in both pairs of AS-PCR primers. Moreover, Dtx5 is more highly homologous with Dx2 than Dx5 from their protein sequences.