Phosphate Fertilizer Application Amount for High Yield of Wheat and Environmental Safety in Fluvo-aquic Soil Region

In order to determine a reasonable phosphate fertilizer application amount for wheat in fluvoaquic soil of Henan province,the effects of different phosphate fertilizer application amount on the wheat yield,residual amount of available phosphorus and phosphate fertilizer use efficiency were studied. The results showed that the application of phosphate fertilizer significantly increased grain yield and promoted phosphorus absorption in the wheat shoots,but excessive phosphate fertilizer had inhibitory effect on wheat yield. With the increase of phosphate fertilizer application rate,wheat yield first increased and then decreased,the phosphate fertilizer( P2O5) application rate for the highest grain yield was 90 kg /ha,followed by 180 kg / ha,the difference between them was not significant; phosphate fertilizer use efficiency gradually decreased,the residual amount of Ca Cl2-P,Water-P and Olsen-P increased,the surplus amount of phosphorus increased in plough layer soil. Take into account of the wheat yield,residual amount of available phosphorus and phosphate fertilizer use efficiency,the recommended phosphate application rate for wheat was 90—180 kg / ha to ensure the high yield and the environmental safety.