Frequencies of High and Low Molecular Weight Glutenin Subunits in Durum Wheat Grown in Syria

One hundred and forty durum wheat genotypes were used in this study. They were divided into four groups: I- mutant lines (50) II- local varieties (20), III- ACSAD lines (22) and IV-ICARDA lines (48). The genotypes were studied for the composition of high (HMWGS) and low (LMWGS) molecular weight glutenin subunits as determined by sodium dodecyl sulfate-poly acrylamide gel electrophoresis (SDS-PAGE). All studied genotypes possessed the null allele at Glu-A1 The results demonstrated that durum wheats differed in the allelic compositions at Glu-B1. Four different allelic subunit combinations were realized at Glu-B1 with 7+8 being the most frequent and 6+15 the least frequent subunit combinations. 7+8 were abundant in groups I and III whereas subunit 20 was most frequent in groups II and IV. At Glu-B3 locus, LMW1 constituted 41% and LMW2 appeared in 59% of the genotypes. However, LMW1 was the sole allele in group I (100%) as compared to LMW2 which constituted 85%, 90% and 94% of Glu-B3 in groups II, III and IV respectively. These results differed from those reported in the literature and were discussed in terms of their potential use in breeding programs.