Effects of Glu-D1 gene introgressions on soft white spring durum wheat (Triticum turgidum ssp. durum) quality

Background and objectives Utilization of durum wheat (Triticum turgidum ssp. durum) is limited by its weak gluten and poor bread-making quality. One strategy to improve gluten strength and bread-making quality is by introducing the Glu-D1 alleles from bread wheat. Findings Introduction of Glu-D1 alleles Glu-D1a and Glu-D1d, corresponding to the High Molecular Weight Glutenin subunits Dx2 + Dy12 and Dx5 + Dy10, respectively, increased dough strength as evidenced by SDS sedimentation volume, Lactic acid Solvent Retention Capacity, and Mixograph dough mixing parameters. The Glu-D1d Dx5 + Dy10 allele was "stronger" than the Glu-D1a Dx2 + Dy12 allele. However, whereas Dx2 + Dy12 improved straight-dough pan bread volume, Dx5 + Dy10 did not. This latter result was ascribed to the overly strong, inextensible gluten contributed by the Glu-D1d Dx5 + Dy10 allele. Conclusions Whereas both Glu-D1 alleles increased dough strength, Dx2 + Dy12 improved bread loaf volume but lines with Dx5 + Dy10 produced doughs that were too strong to realize an increase in loaf volume. The results confirm the notion that large bread loaf volume is achieved with a balance of dough extensibility and elasticity. Significance and novelty Durum wheat production and consumption will increase as bread quality improves. The Glu-D1 high molecular weight glutenin proteins will likely play a role in improving bread-making ability. The two major Glu-D1 alleles are accessible via durum wheat translocation lines.