Effect of nitrogen fertilization on winter wheat quality

A field experiment was conducted to investigate the effect of nitrogen fertilizer applications on some quality components of wheat. For winter wheat genotypes (Ana Morava, Vizija, L-3027 and Perla) were grown at Small Grains Research Centre Kragujevac in three years (2005–2007) at three levels of nitrogen fertilization (N1 = 60 kg N ha−1, N2 = 90 kg N ha−1 and N3 = 120 kg N ha−1). Zeleny sedimentation value and wet gluten content in divergent wheat genotypes were analyzed in depending on the nitrogen nutrition and years. Nitrogen fertilization significantly increased sedimentation value and wet gluten content. The highest increasing of both traits established in N3 variant when applied 120 kg ha−1 of nitrogen. Genotypes reacted differently to N level increasing. Cultivar Perla had the highest value of sedimentation and wet gluten content and this cultivar the best reacted to increasing N levels. Statistically significant differences for sedimentation value and wet gluten content were found among cultivars, years, N-doses and for all their interactions. The results have shown that the best quality of wheat was with nitrogen applied of 120 kg N ha−1. Correlation between nitrogen applications and sedimentation value was significant (r = 0.208*), while between N-doses and wet gluten content was high significant (r = 0.290**). Sedimentation value and wet gluten content positively correlated (r = 0.783**)

Effects of Genotype, Season, and Nitrogen Nutrition on Gene Expression and Protein Accumulation in Wheat Grain

Six commercial U.K. cultivars of winter wheat selected to represent different abilities to partition nitrogen into grain protein were grown in replicated field trials at five different sites over three seasons. The proportion of LMW glutenin subunits decreased and the proportion of gliadins increased during grain development and in response to N application. Differences were observed between the proportions of LMW glutenin subunits and gliadins in low- and high-protein grain, these two fractions being decreased and increased, respectively. There was little effect of grain protein content on the proportions of either the HMW glutenin subunits or large glutenin polymers, which are enriched in these subunits, with the latter increasing during development in all cultivars. The proportion of total protein present in polymers in the mature grain decreased with increasing N level. Correlations were also observed between the abundances of gliadin protein transcripts and the corresponding proteins