Evaluation of Allelic Diversity of Genes Encoding Glutenin and Gliadin in Bread Wheat and its Some Relatives

To study the genetic and allelic diversity in the genes encoding glutenin and gliadin proteins in wheat landraces, 98 Triticum accessions belonging to four species: T. aestivum, T. boeoticum, T. durum and T. uartu collected from different provinces of Iran were used. 13 pairs of low molecular weight glutenin primers (LMW-GS), four pairs of high molecular weight glutenin primers (HMW-GS) and four pairs of gliadin primers were amplified 1327, 548 and 152 segments, respectively. The highest genetic diversity was observed in the Glu-3A gene block, which belongs to the low molecular weight glutenin, and 13 primer pairs amplified a total of 34 alleles from 180 to 1500 bp in length, of which 11 alleles were previously reported and 23 alleles were identified as possibly new alleles. In the Glu-A1 gene block, which belongs to the high molecular weight glutenin, most allelic polymorphisms were amplified by the primers Glu-A1 and Xrj5. In the Gli-A2 gene block, only one allele was amplified by two specific primers: Gli-AS6 and Gli-AS5. The highest and lowest number of effective alleles belonged to T. aestivum and T. uartu. The average of Nei diversity index was 0.19 and its highest and lowest values ​​were related to T. aestivum and T. uartu. Based on the clustering method, 98 accessions were divided into two main groups. In the first main group, the accessions related to two species T. aestivum and T. durum were placed, which shows the greatest genetic similarity between the two species. In the second main group were placed two wild species T. boeticum and T. uartu. In overall, a large allelic diversity was observed for low molecular weight glutenin subunits in the studied Triticum species, which highlights the potential of these species as a valuable germplasm for breeding programs aimed to the bakery quality improving in wheat.