Contribution to Breadmaking Performance of Two Different HMW Glutenin 1Ay Alleles Expressed in Hexaploid Wheat

Two expressed alleles of the 1Ay high-molecular-weight glutenin subunit (HMW-GS), and , previously introduced in durum and bread wheat, were separately introgressed into the Australian bread wheat ( L.) cv. Livingston. The developed lines had different allelic compositions compared to that of the parental cultivar ( ), having either + or + at the locus. Since and are known to have the same effects on quality, differences observed between the two sets of the developed lines are attributed to the two introgressed genes. Yield and agronomic performance of the lines were evaluated in the field, and the protein, dough, and baking quality attributes were evaluated by large-scale quality testing. Results demonstrated that the subunit 1Ay21* increased unextractable polymeric protein by up to 14.3% and improved bread loaf volume by up to 9.2%. On the other hand, subunit increased total grain protein by up to 9% along with dough elasticity. Furthermore, milling extraction was higher, and flour ash was lower in the lines compared to the lines integrating . Both sets of the 1Ay introgression lines reduced dough-mixing time compared to the recurrent parent Livingston. The results also showed that had a higher potential to improve the baking quality than under the Livingston genetic background. Both alleles showed the potential to be utilized in breeding programs to improve the breadmaking quality.