The 3414design was used to study the optimal supplying rates of N,P and K for winter wheat in fluvo-aquic soil.The results indicated that the yield of the full fertilization treatment increased by 35.14%,5.62% and 1.66% respectively compared to the nitrogen-starved treatment,phosphorus-starved treatment and potassium-starved treatment.The effect of nitrogen fertilization was the best.Based on the one variable quadratic model regression analysis,the optimal supplying rates of N,P2O5 and K2O were 271.5,90.0 a...