The efficiency of applying phosphate on rice and utilization rate in calcareous fluvo-aquic soil

The effects of different phosphorus fertilization level on soil rapid available phosphorus and rice yield are studied in calcareous fluvo-aquic soil of Tongzhou area,the utilization rate of phosphate fertilizer is determined in different phosphorus fertilization level.The results show:the phosphate fertilizer coefficient of calcareous fluvo-aquic soil is 1.72 in middle containing phosphorus soil,the critical value is 6.0 mg/kg;the reasonable applying phosphate fertilizer can significantly increase the yield of rice,and the yield is increased with the increasing of applying phosphate amount below a certain phosphorus fertilization level,the best phosphorus fertilization amount is 3.8 kg,and the phosphorus fertilization amount of the highest yield is 9.4 kg.The phosphate utilization rate is decreased with the increasing of applying phosphate amount,the average utilization rate is 8.5%.