In order to explore the effects of water and nitrogen management on winter wheat yield and water and nitrogen use efficiency under drip irrigation, a field experiment of two consecutive winter wheat growing seasons with drip irrigation system was carried out from 2019 to 2021, with two nitrogen application levels: N1 (210 kg·hm-2) and N2 (240 kg·hm-2), and four irrigation amounts: W1(no irrigation), W2, W3, and W4 (30 mm, 45 mm, and 60 mm irrigation each time, respectively). The related indices of wheat yield, and water and nitrogen use efficiency under different treatments were analyzed. The results showed that nitrogen application rate and irrigation amount significantly affected on the net photosynthetic rate of leaves in the key growth period of winter wheat, and their effect on the net photosynthetic rate of leaves at heading, flowering and grain-filling stages of winter wheat in two consecutive growing seasons were the highest under N2W4 treatment, followed by N1W4 or N2W3 treatments, yet there was no significant difference among the three treatments. The contents of soil ammonium nitrogen and nitrate nitrogen in the key growth stages of wheat in the two consecutive wheat seasons were the lowest under N2W3, N1W4 or N2W4 treatments. Moreover, soil ammonium nitrogen was significantly negatively correlated with yield and partial factor productivity of nitrogen fertilizer(NPFP) at overwintering, grain-filling and harvest stages. Meanwhile, soil nitrate nitrogen was significantly negatively correlated with yield and NPFP at heading, grain-filling and harvest stages. Water and nitrogen management significantly improved the yield, and water and nitrogen use efficiency of winter wheat, in the two consecutive winter wheat seasons, with the increase rate of 38.9%-62.0% and 40.9%-68.3% for wheat yield, respectively, and 8.0%-15.7% and 10.1%-16.4% for water use efficiency(WUE), respectively, and 38.9%-62.0% and 40.9%-65.5% for the NPFP, respectively. The yield and WUE of winter wheat in the two consecutive growing seasons were the highest under N2W4 treatment, followed N2W3 treatment, and there was no significant difference between the two treatments. However, the irrigation efficiency of N2W3 treatment was significantly higher than that of N2W4 treatment in the two consecutive wheat growing seasons. In summary, the nitrogen application rate of 240 kg·hm-2 and the irrigation amount of 45 mm each time (N2W3) was the best water and nitrogen management mode for drip irrigation under this experiment conditions, which can achieve the optimal goal by ensuring yield with improved water and nitrogen use efficiency. |