Effect of Glu‐D1 introgression on dough‐ and pasta‐making quality of durum wheat lines with different glutenin composition and amylose content
Authors: Sissons Mike , Sestili Francesco , Lafiandra Domenico 
Published: January 2019

Background and objectives

Durum wheat is mainly used for the production of pasta, but a significant amount is also used for bread and other products worldwide. However, leavened bread made from durum wheat flour or as blends results in bread with lower loaf volume compared to bread made from hexaploid wheat probably due to poor dough strength and/or extensibility. Durum wheat lacks the glutenin subunits important in bread making, in particular the Glu‐D1 subunit 5 + 10. Efforts are being made by researchers to introduce high molecular weight glutenin subunits (HMW‐GS), specifically 1, 2*, 17 + 18, 2 + 12, and 5 + 10 and combinations into durum wheat to improve baking quality. Typically, this work has not evaluated pasta‐making quality and dual purpose durum wheat is desirable. This work reports the effects of the addition of HMW‐GS 2 + 12 and 5 + 10 in various durum wheat backgrounds on dough‐ and pasta‐making quality.

Findings

Durum wheats, Svevo, Svevo partial waxy (null 4A, null 7A, low amylose ~14%), and Lira biotypes 42/45 differing in their LMW‐GS as type 1, weak dough, and type 2, strong dough, respectively, were compared with lines having the Glu‐D1 subunit pair 2 + 12 or 5 + 10. For Svevo, the Glu‐B17 + 8 subunits were removed. The absence of 7 + 8 in Svevo reduced the over strong dough strengthening effect, especially from 5 + 10 but also 2 + 12 found previously when 7 + 8 is present. The weak gluten Lira42 genotype benefited from the improved dough strength from 2 + 12/5 + 10, and both Lira biotypes showed much larger effects on dough strength from the Glu‐D1 pairs than with Svevo, a better quality variety. The impacts on pasta were variable depending on the genotype. For Lira42, the presence of 2 + 12 lowered stickiness and cooking loss while stickiness was only reduced in Lira45 with 5 + 10. For Svevo (without 7 + 8), there was little to no impact on pasta quality from the presence of either 2 + 12 or 5 + 10. The very low amylose Svevo (SvLA) pasta quality was improved greatly by 5 + 10 improving firmness and reducing stickiness and cooking loss although still softer than Svevo.

Conclusions

Manipulation of the glutenin composition of durum wheat by introduction of Glu‐D1subunits 2 + 12 or 5 + 10 in various durum backgrounds had different effects. Generally, dough strength was improved more so in the weaker dough strength genotypes with these subunits and removing Glu‐B17 + 8 from Svevo provided a more balanced dough strength. Pasta firmness in Svevo and Lira with these subunits was not affected, and there were minimal changes in other pasta properties except an improvement in pasta stickiness in Lira. In the variable amylose Svevo genotypes, the 5 + 10 subunit pair improved pasta firmness of the overly soft low amylose waxy pasta and reduced stickiness.

Significance and novelty

Manipulation of the glutenin subunit composition of durum wheat by introduction of Glu‐D1 subunits affected dough properties, improving dough strength in genotypes with weak gluten. This study found minor impacts on pasta quality allowing the flexibility to develop durum with a better balance of glutenin subunits more suited to bread making without adversely affecting pasta‐making quality and acceptability.