Simulation on water requirement of wheat during growth period by APSIM

To find the rational use of water resources for wheat growth periods, this study used the APSIM model to simulate wheat yield under different growth periods with changeable rainfall and estimate the threshold value for requirement of wheat for water at different growth periods. This study showed that the regional precipitation pattern generally showed an alternation from droughts to floods, and the requirement of wheat for water during whole growth periods was 325.3 mm, in which the requirements of wheat for water during emergencing, jointing, heading, flag leaf, flowering and grain filling periods were 34.72, 80.6, 67.1, 43.81, 58.67 and 30.4 mm, respectively, and accounting for 10.67%, 27.85%, 20.63%, 13.47%, 18.04% and 9.35% of total precipitation during wheat growth periods. Precipitation deficitwas 70.78%, 48.83%, 46.22%, 40.35%, 75.66%, -121.05% at, jointing, heading, flag leaf, flowering, grain filling period, respectively, which indicated that the key periods of spring wheat for requiring water were emergencing, jointing and flowering period.