Allelic variation for the high- and low-molecular-weight glutenin subunits in wild diploid wheat (Triticum urartu) and its comparison with durum wheats

Triticum urartu is a wild diploid wheat identified as donor of the A genome in polyploid wheats. This species could be used as a genetic resource for wheat quality breeding. The HMWGs and B-LMWGs of this species were analysed by SDS-PAGE in 169 accessions from Armenia, Iran, Iraq, Lebanon, the former Soviet Union, and Turkey. Seventeen alleles for the Glu-A(u)1 locus and 24 for the Glu-A(u)3 locus were found. The allelic variation was asymmetrically distributed, Turkey being the country where the largest number of alleles was found. Genetic diversity was high, although a great part of this diversity is at risk of erosion given that the distribution of the combinations among the evaluated accessions was not random. Consequently, the loss of these accessions could mean the disappearance of the allelic variants. The alleles found for both loci were different from those detected in cultivated wheats. These results provided new basic knowledge regarding the genetic variability of the seed storage proteins synthesised by the A(u) genome, as well as their potential to create novel germplasm for quality breeding in wheat programs.