Effect of NPK fertilization on rapeseed and optimal rate of fertilizer for interplanting rapeseed of no-tillage cotton-rapeseed rotation system

A field experiment was conducted on interplanting rapeseed in the no-tillage cotton-rapeseed system.The aim was to study the effects of nitrogen(N),phosphorus(P) and potassium(K) fertilization on yield,economic benefit and optimal rates of fertilizers for rapeseed.The result showed that fertilizers promoted both vegetative and reproductive growth of rapeseed,which further significantly improved seed yield and profit.It indicated that their effects on yield and profit was ranked as NPK.Based on the fertilizer response equations from the trial,the most effective fertilization rates for rapeseed were 205kg N /hm2,76kg P2O5/hm2 and 35kg K2O/hm2,respectively.