Allelic Variation of High Molecular Weight Glutenin Subunits in Bread Wheat Cultivars Using Allele Specific Markers

Endosperm storage proteins are important factors affecting wheat grain quality, so that high molecular weight glutenin subunits play a key role in the gluten formation and structure and are closely related to wheat quality. To investigate the allelic variation at the loci coding high molecular weight glutenin subunits (HMW-GS) among 25 bread wheat genotypes of, nine allele-specific primer pairs (Glu-A1, Glu-B1, Glu-D1) were used. Results showed that at the Glu-A1 locus, three allele (AxNull, Ax1 and Ax2*) were identified. The highest frequency belonged to allele Ax2* (56%). At the Glu-B1 locus, six alleles were detected, totally. The allelic combination of Bx7CDܯ was 32% in frequency which showed the highest frequency. At the Glu-D1 locus, two alleles were detected. At this locus, allelic combination of Dx2­༭ had the highest frequency of 82% among the detected alleles. The Pfluger scoring system was utilized to score Glutenin composition. The studied genotypes showed different allelic combinations with a different level of quality score. Most of genotypes were ranked as good to excellent bread-making quality. Cluster analysis grouped all high quality cultivars in a separate cluster. The variations identified in this study can be a valuable resource of allelic diversity for breeding programs to improve the quality of wheat.