Variation in concentrations of high-molecular-weight glutenin subunits and macropolymers in wheat grains of a recombinant inbred lines population and in two contrasting eco-sites in China.

Background: Concentrations of high-molecular-weight glutenin subunits and macropolymers in wheat grains are important indicators of grain quality, which are genetically determined and affected by environmental factors. The 6 VS·6AL translocation chromosome segment is reported to own high powdery mildew and yellow rust resistance genes of Pm21 and Yr26. This study investigated the variation in concentrations of high-molecular-weight glutenin subunits (HMW-GS) and glutenin macropolymer (GMP) in response to the 6 VS·6AL translocation segment and the two contrasting sites.

Results: Large variations in concentrations of HMW-GS and GMP were observed within lines containing different HMW-GS compositions and between the contrasting eco-sites. However, 6 VS·6AL chromosome translocation segment showed no significant effects on concentrations of HMW-GS and GMP. In addition, HMW-GS concentration was also found to be significantly correlated with the GMP concentration.

Conclusion: Concentrations of HMW-GS and GMP are largely affected by the eco-sites and the composition of HMW-GS, whilst not by the presence of 6 VS·6AL chromosome segment translocation. The 6 VS·6AL translocation is suggested as potential donor for breeding wheat cultivars for high resistence to powdery mildew and yellow rust with less risk of undesirable effects on grain quality.