Water use efficiency and optimal supplemental irrigation in a high yield wheat field

Abstract

An eight-year field study was conducted in this region from 2007 to 2015, with the same water and fertilizer management used in the sowing stage of winter wheat, which then received supplemental irrigation (SI) or no irrigation (rain-fed). The proportion of water consumption from jointing to maturity averaged 56% under rain-fed conditions, but reached 64% under the optimal SI conditions. The main water supply during the different growth periods that was suitable for achieving both high yield and high water use efficiency (WUE) had a nearly constant volume. These results provide important theoretical and technical support for on-demand irrigation by model forecasting. The results also indicated SI, as determined by simultaneously considering the precipitation change, soil water storage condition, and crop evapotranspiration status, is an important way to achieve high yield and conserve water in winter wheat.