The relative supply of carbohydrate and nitrogen to wheat grains, and an assessment of the shading and defoliation techniques used for these determinations

Abstract

Leaf contribution to grain dry weight and grain nitrogen was estimated in four varieties of wheat from their responses to shading and defoliation treatments. The relation between movement of nitrogen and dry material from leaves to grains appeared as an important factor in the differences between varieties in respect to the percentage nitrogen content of grains. Experiments with labelled carbon, however, showed that there was a significant redistribution of assimilates from other parts when the ear was shaded or the flag leaf removed.