Water Use Efficiency of Water and Fertilizer Coupling on Spring Wheat

With 312-D optimized saturation design, a four-year field experiment is conducted in the western Liaoning on spring wheat to study water use efficiency(WUE). The results show that irrigation quantity is the chiefly factor to affect spring wheat WUE,phosphorus quantity is the secondly factor,nitrogen quantity is the thirdly factor. Nitrogen and phosphorus are positive effects,but water is negative effect to increase WUE. The effects order of interaction between nitrogen and water,nitrogen and phosphorus are markedly positive effects,but effect between phosphorus and water is not markedly negative effects. When spring wheat WUE accesses 10 kg/(hm~2.mm),the amounts of water and fertilizer are nitrogen 102.6～239.3 kg/hm~2,phosphorus 84.3～139.0 kg/hm~2,water 41.0～170.9 mm. The amount for highest WUE is nitrogen 220.6 kg/hm~2,phosphorus 76.0 kg/hm~2,water 117.4 mm.