Effects of wheat cultivar and nitrogen application on storage protein composition and breadmaking quality

Influences of cultivar and nitrogen application on protein concentration and composition, and amount and size-distribution of different protein components, were investigated in 10 spring wheat cultivars (Triticum aestivum L.) with widely varying gluten strength, grown under four nitrogen fertilizer conditions. The results showed that cultivar differences in gluten strength were determined by storage protein composition, differences in total amount of HMW glutenin subunits, the glutenin-to-gliadin ratio, and the relationship between SDS-soluble and SDS-insoluble protein polymers. Negative correlations were found between protein parameters related to gluten strength and bread volume. No cultivar stability for gluten strength in relation to differences in nitrogen application was found. Thus, the gluten strength was influenced by the nitrogen application in all the investigated cultivars. increased nitrogen supply correlated significantly to an increase in all protein components containing gliadins and glutenins, but not to those containing albumins and globulins. The increase in protein components containing gliadins and glutenins correlated significantly with an increase in protein concentration and bread volume.