Allelic diversity of low molecular weight glutenin subunit at Glu-A3, Glu-B3 and Glu-D3 loci in Iranian spring bread wheat landraces

Baking quality is one of the most important priorities in bread wheat breeding programs. Therefore, breeding of high yielding cultivars with high baking quality is very important. In the present study, allelic diversity of low-molecular-weight glutenin genes was analyzed in 154 Iranian spring bread wheat landraces and Chines Spring variety using group-specific primers. In Glu-A3, Glu-B3 and Glu-D3 loci, in total 12, and 9 alleles, were amplified, respectively. In Glu-A3 locus, using two primer pairs Glu3A.2 and Glu3A.3 gene sub-groups coding proteins with the N-terminal sequences of MDTSCIP- and METSCIP- was amplified. The fragment of 700-bp length with 45.3% and fragment with size of 742-bp with 0.2% showed maximum and minimum frequency in this locus. In Glu-B3 locus, using Glu3B.2 primer pair designed based gene on sub-groups coding proteins with the N-terminal sequence of METSHIPG-, two fragments of 440 and 421-bp with frequency of 73.2 and 26.8%, were amplified, respectively. The Glu3D.2, Glu3D.3 and Glu3D.4 primer pairs designed, based on gene sub-groups coding proteins with the N-terminal sequences of METSRV-, METCIP and METSCIP-, were used to amplify Glu-D3 locus. The 700-bp allele with 34% and 589-bp allele with 0.7% showed maximum and minimum allele frequency in this locus. The PIC value ranged from 0.09 to 0.72 with an average of 0.22 and gene diversity or expected heterozygosity was in the range of 0.1 to 0.76 and mean value of 0.24. Molecular analysis of variance for allele diversity of LMW-GS genes showed that the variances within groups and between groups were 87 and 13%, respectively.