The Study on the Application of Nitrogen and Phosphorus Reduction on Rice

The effects of different fertilization reduction on double-crop rice growth and yield were studied on the basis of farmer conventional fertilization.The results of nitrogen reduction showed as follows.The highest yield was obtained with the application of slow release fertilizers.Compared to conventional nitrogen fertilizer application(CFN).0.4% higher yield was gained with 80R whose N application rate was 20 percent lower than that of local fertilizer application.In comparison to the treatment with equal amount of nutrition content(80F),6.0% higher yield was gained in 80R.The treatment of organic manure combined with chemical fertilizer(30F+50M) had 1.9% higher yield as comparison with 80F treatment.The yield of green manure combined with chemical fertilizer(50F+30A) decreased 7.2% as comparison with 80F treatment.Therefore,the yield was increased on slow release fertilizers or organic manure combined with chemical fertilizer application on condition that the fertilization amounts was reduced.The results of phosphorus reduction showed that the treatment with 20 % lower amount of phosphorus than conventional phosphorus fertilizer application(CFP) did not reduce the yield,soit should be possible to reduce 20% local phosphorus level.