| In the experiment, nitrogen level and its translocation efficiency in the flagleaves of two wheat cultivars (cv. Jian 17 and Lumai 21) were studied at four soil moisture levels. Moderate and severe soil drought significantly decreased the relative water content, chlorophyll content, photosynthetic rate, stomatal conductance, nitrogen level and yield, but moderate drought increased nitrogen efficiency and grain protein content. The cultivar with high grain protein content had higher nitrogen efficiency, although its nitrogen content in flag leaves was lower, which showed that soil drougnt sharply stimulated the accumulation of grain protein. It is suggested that moderate soil water deficit may enhance nitrogen translocation from leaves to grains so that the grain quality improves. |