Genetic mapping analysis of bread-making quality traits in spring wheat

In this study we assess the genetic architecture of bread-making quality traits in spring wheat (Triticum aestivum L.). A mapping population derived from BR34 and 'Grandin' was used to measure 20 end-use quality traits including six kernel, seven milling and flour, four dough mixing strength, and three bread-making traits. A total of 31 quantitative trait loci (QTL) significantly associated with all but two traits were identified. These QTL were clustered in five chromosomal regions, namely 1BS, 1DL, 4BL, 5BL, and 6AS, and explained a large proportion of trait variation with favorable alleles contributed by both parents. The 1DL cluster containing the high molecular weight glutenin gene, Glu-D1, had a large genetic influence on dough mixing strength and bread-making performance. Most of the QTL affecting kernel traits were clustered on 6AS. Inconsistency of QTL locations detected from different environments was observed for the flour and milling traits and was likely due to genotype × environment interaction (G × E) effects. Despite high heritabilities estimated for the 20 quality traits evaluated, no QTL were found for flour brightness and bake water absorption, suggesting that these traits may be controlled by QTL with small effects that could not be detected due to the small population size. Because of the complex inheritance of these traits, it will be necessary to validate these QTL in different spring wheat backgrounds evaluated in similar growth conditions as used in this study before the marker information can be used for breeding applications.