Phenotypic variation and QTL analysis for oil content and protein concentration in bread wheat (Triticum aestivum L.)

Abstract

The lipid content of wheat is small yet could potentially contribute to increased calorific value of grain delivered for livestock and human consumption. Breeding for greater oil content is required but there is little understanding of the extent or nature of genotypic variation for oil concentration in wheat. A diverse range of commercial and novel spring wheat germplasm was assessed in two years under favourable conditions to understand the extent of genetic variation for lipid content. Genotypic differences were modest in size (4.27–5.32 %) but repeatable across years (rs = 0.71, P 0.05). QTL mapping was undertaken in the CD87/Katepwa wheat population phenotyped for grain oil and protein concentration in two years. Both total grain lipid and protein concentrations varied significantly across progeny ranging from 3.87 to 5.77 and 11.3 to 15.6 %, respectively while the ranking of lines for oil content was high (rs = 0.72, P 0.05). The identification of diverse wheat sources with higher oil content together with improved genetic understanding suggests potential for genetic improvement of oil content in the development of higher oil wheats.