Effect of fertilizer levels and irrigation on yield of rice in black soil area

Reasonable recommended fertilizer rates and irrigation quantities are the basis for optimizing the nutrients and water efficiency and increasing the rice yield.This work analyzed the results with the 3414 designed filed experiment and concluded that the integrated recommended fertilizer rates of rice in this area were 167.4 kg·hm-2(N),27.9 kg·hm-2(P2O5) and 52.8 kg·hm-2(K2O),respectively;the result also showed that the optimal irrigation pattern was shallow water irrigation from the middle-tillering to the maturity.When irrigation water increased from 85% saturated water content to 100% saturated water content,there was a positive interaction between the irrigation pattern and nitrogen rates,showing that nitrogen might increase the rice yield at 100 % saturated water content.