Genetic control of processing quality in a bread wheat mapping population grown in water-limited environments

End-use quality of bread wheat (Triticum aestivum L.) is affected by both genetic and environmental variation. Current understanding of the genetic control of wheat quality traits is mainly based on genetic experiments conducted using grain produced in favourable conditions. The objective of this research was to extend the genetic analysis of these traits by using grain produced in water-limited environments. Grain samples harvested from a mapping population grown in field experiments at two locations in Australia were used to assess characteristics of the grain, flour, dough and bread. Quantitative trait loci (QTLs) were mapped. The parents of the population, RAC875 and Kukri, differ at several loci that are known to affect grain quality or plant phenology. Of these, a high-molecular-weight glutenin locus (Glu-B1) affected dough properties, the puroindoline-encoding Ha locus affected grain hardness, flour and loaf properties and a photoperiod response locus (Ppd-D1) affected flour extraction and protein content. Similarly, several previously reported quantitative trait loci (not associated with specific genes) also had effects in the stress environments used here. In addition, novel loci were detected for bread wheat quality traits; their effects may be specific to materials grown in water-limited environments.

► Wheat grain grown in water-limited environments was used in genetic mapping. ► Several known genetic loci affected flour, dough and loaf properties. ► Novel, possibly stress-specific, quantitative trait loci were discovered.