Factors affecting the occurrence of mottling in wheat

Abstract

Several varieties of wheat were grown in pot culture with different levels of applied phosphorus, sulphur, nitrogen, and water. These treatments affected the incidence of mottling in all varieties, irrespective of their ordinary grain type. High amounts of nitrogen relative to other nutrients, and restriction of watering after flowering, increased the proportion of vitreous (non-mottled) grains. Vitreous grains generally had a higher nitrogen percentage than mottled grains. The total nitrogen content (N per 1000 grains) of vitreous grains in the nutritional trials was high, but that of vitreous grains in the watering experiment was lower. These latter grains had a high nitrogen percentage by virtue of reduced size. It is likely that vitreous grains due to both effects may be found in commercial samples.