Initial Research on Yield Effect of Nitrogen,Phosphorus and Water Coupling on Spring Maize in Semi-arid of Blown Soil

With 312-D optimized saturation design,field experiment was conducted to study yield effect of water and fertilizer coupling on spring maize.Results showed that nitrogen quantity was the chief factor to affect spring maize yield,irrigation quantity was the second factor,phosphorus quantity was the third.The type of interaction between nitrogen and phosphorus,phosphorus and water was substitutive for increasing yield,but that was positive between nitrogen and water.The effect order of interactions was nitrogen and phosphorus coupling phosphorus and water coupling nitrogen and water coupling.Amounts for highest yield 9 374.0 kg/ha were nitrogen 281.7 kg/ha,phosphorus 127.1 kg/ha and water 75.2 mm.And amounts for highest profit 6 023.5 yuan/ha were nitrogen 211.2 kg/ha,phosphorus 110.5 kg/ha and water 24.1 mm