Agronomic and environmental impacts were studied in a field experiment to determine water availability and protein formation interrelations. Three winter wheat varieties and six nitrogen application levels were applied in two crop years representing different precipitation and temperature patterns to evaluate yield, yield components and quality manifestation. The results obtained suggest that precipitation patterns in relation with the different wheat development phenophases had profound influence on the protein formation of wheat crop. Protein yield of wheat crop was almost double in favourable crop years in comparison to that of the unfavourable crop year.

Keywords: winter wheat, protein, precipitation, temperature, crop year effect