Abstract: Aroot growth device was used to study the effect of water supply from deep soil on dry matter production of winter wheat. The results show that soil with high moisture in deeper layer and low moisture in upper layer (treatment LH) still maintains a higher water content both in soil and in plant leaf during the milking stage of wheat growth. This treatment gives the highest dry weight of roots, flag leaves and spikes, and hence, a maximum yield potential. It seems that such a soil moisture status is beneficial to promoting root development in deeper soil, balancing water utilization, and improving crop yield.

Key words: Winter wheat, Root system, Water utilization, Yield, Matter allocation, yield, rapeseed (Brassica napus), nitrogen use efficiency., nitrogen application, waterlogging