Preliminary study on the optimal application of N,P and K in maize under different soil fertility

In order to provide scientific fertilizer basis for maize,the3414regression design model was applied to study the relations between yield of maize and application amounts of N,P and K, and the supply potential of soil nutrient under different soil fertility in Zhuozhou,Hebei Province. The equations of fertilizer function under such three levels as high,middle and low were preliminari- ly estimated.Results show that the amount of optimal application of fertilizers in high soil fertility was N 58.4 kg/hm~2,P_2O_5194.3 kg/hm~2 and K_2O 200.4 kg/hm~2;in medium level,N 187.9 kg/ hm~2,P_2O_5170.3 kg/hm~2 and K_2O 173.2 kg/hm~2;in low level,N 293.4 kg/hm~2,P_2O_5214.8 kg/ hm~2 and K_2O 183.2 kg/hm~2.