A Determination of Relationship between HMW Glutenin Subunits and Bread Making Quality in Bread Wheat

High molecular weight (HMW) subunits of wheat glutenin are generally considered as playing a key role in gluten formation and structure, as well as to be closely related to wheat quality. The endosperm storage proteins of 80 synthetic lines and wheat cultivars (Triticum aestivum) were fractionated through sodium dodecyl sulfate polyacrylamide gel electrophoresis to determine their high-molecular-weight (HMW) glutenin subunit composition and their relationship with bread-making quality. Twenty six high-molecular-weight (HMW) glutenin subunit compositions including fifteen different alleles were found of which 2* allele of Glu-A1, 7+8 allele of Glu-B1 loci and 5+10 of Glu-D1 were of the highest frequency. The 2***+12 subunit, first reported from Pakistan, was observed in 7 lines. SDS sedimentation test was performed to study the effects of HMW Glutenin subunits on bread-making quality. The results of ANOVA showed that 2*, 5+10 and 17+18 alleles of Glu-A1, Glu-D1 and Glu-B1, had the most positive effects while Null allele (43.75%) had the most negative effects on SDS sedimentation trait. Stepwise regression analysis revealed that the subunits of 5+10, 17+18 and 7+8 can justify 31/4% of variation in SDS sedimentation.