Optimization of irrigation scheduling for spring wheat in Hetao Plain with DSSAT model

DSSAT model after calibration and test was used to simulate spring wheat yields under various irrigation schemes with different irrigation water quotas at different growth stages, for the spring wheat “Yongliang 4” at Linhe site in Hetao Plain, in order to optimize the irrigation schemes under different irrigation water supply amounts and to improve irrigation water productivity. The DSSAT-CERES-Wheat model was found to perform satisfactorily in simulating growth period and yield. The irrigation water productivity of spring wheat was found to decrease with increasing total irrigation water amount. Irrigate at tillering stage was found essential to keep spring wheat grow normally. Yield and irrigation water productivity of spring wheat were most sensitive to the irrigation water at jointing stage. Yield and irrigation water productivity of spring wheat were found least sensitive to irrigation water at milk-ripe stage. Irrigation to 30, 105, 30, 30 mm at tillering, jointing, heading and anthesis stages respectively were found to be the best to improve irrigation productivity and efficiency, maintaining wheat yield.