| In article,the author states the effect,which was brought by the planting density,quantity and proportion of nitrogenous and phosphate fertilizer,to the spring rape's yield,benefit and main farming characters in cold,arid area.Meanwhile it builds up mathematical model.According to the model and texts in various area for years,we find the highest yield is 250 kg in 666.7 m2,net profit is over 150 yuan and the best way of farming technical combination is: density 28 400~32 500 plant/666.7m2,pure N 0.826.6 kg/666.7m2,P2O5 8.909.16 kg/666.7m2,N∶P2O5≈1∶2.4. |