Effect of Cultivar and Nitrogen Fertilisation Strategy on the Geometric Characteristics, Size Distribution, and Protein Content of Winter Wheat

Winter wheat grain quality is influenced by genetic and agronomic factors, including nitrogen (N) fertilisation. This study evaluated the effects of cultivar and N fertilisation strategy on the grain yield, some physical and geometric properties, colour, and chemical composition. Two cultivars, Activus and Chevignon, were compared under three N strategies: 40, 100, and 170 kg N ha−1 (N40, N100, and N170). Grain yield and its components did not differ significantly between cultivars or among N fertilisation strategies. The number of grains per ear was numerically higher in Chevignon, but the difference between cultivars was not statistically significant. Cultivar affected bulk density and grain size distribution; Activus had a higher bulk density and a higher proportion of grains > 2.8 mm, whereas Chevignon had more smaller grains. Increasing N supply did not affect the geometric characteristics of wheat grains. The colour parameters a*, b*, and chroma were highest under N40 and lowest under N170, whereas hue showed the opposite trend. Dry matter (DM) and crude protein (CP) differed between cultivars, and CP was also affected by N strategy. Phosphorus (P) and magnesium (Mg) contents did not differ statistically in relation to the independent variables included in the experiment.