应用~(15)N~(32)P示踪技术研究水稻对不同复(混)合肥料中氮磷的吸收

在盆栽条件下几种复(混)合肥料对水稻均有增产作用,与对照相比稻谷增产60.8—77.7％,达到显著水准。但几种复(混)合肥之间无显著差异。用15～(N)示踪法测定水稻对复(混)合肥的氮素利用率:尿素磷铵为44.7％,氯磷铵为44.5％,尿素为44.1％,尿素加普通过磷酸钙(简称普钙)为40.8％,硝酸磷肥为36.4％。说明硝酸磷肥不宜于水稻田施用。用~(32)P示踪法测定水稻对几种复(混)合肥的磷的利用率:硝酸磷肥为22.6％,氯磷铵为22.4％,尿素磷铵为21.1％,尿素加普钙为20.7％,普钙为11.9％。水稻对供试复(混)合肥料磷的利用率均显著高于普钙。

STUDIES ON ABSORPTION AND UTILIZATION OF N AND P IN COMPOUND FERTILIZERS BY RICE USING TRACER TECHNIQUE OF ~(15)N AND ~(32)P

It was shown in this experiment that all compound fertilizers tested had a significant effect on yield of rice compared with control. The range of increased grain yield was 60.8-77.7%. But there was no significant difference among the compound fertilizers. By using isotope 15N tracer,the efficiency of nitrogen utilization by rice was found as follows:urea-ammonium phosphate 44.65%,ammonium phosphate-chloride 44.54%,urea 44.12%, nitric phosphate 36.65%. The nitric phosphate could not be used in paddy field.The results with isotope 32P showed that the efficiency of utilization of phosphorus by rice was as follows:22.55% for nitric phosphate, 22.36% for ammonium phosphate-chloride, 21.08% for superphosphate. The utilization rate of phosphorus of all compound fertilizers was significantly higher than that of superphosphate.