Optimum Application Amount and Ratio of Fertilizers for High Yield of Hot Pepper in Greenhouse of Ningxia

Effect and optimum application rate of bio-organic manure,N,P and K in hot pepper production in Yinchuan Plain were studied using quaternion uniform-precision rotatable central composite design.The result shown that the soil has less available N,but more available P and K,and mild salinization characteristics due to high fertilizer application and drainage problem.N is the determination factor for hot pepper growth and production.The order of four fertilizer effect on hot pepper growth is:Norganic manurePK.The optimal application amount of organic manure,N,P2O5 and K2O is 3000~6000 kg·hm-2,633~750 kg·hm-2,75~225 kg·hm-2,and 90~225 kg·hm-2 respectively for 51.13~63.6 t·hm-2 hot pepper yield.The reasonable ratio of m(N)∶m(P2O5)∶m(K2O) is 10∶1∶1.2.