ABSTRACT

To improve the grain yield (GY) and water–nitrogen (N) use efficiency of summer maize, a 2–year field experiment was conducted using micro–sprinkling irrigation water–fertilizer integration. Surface irrigation and N application methods were applied in the control (CK, irrigation at sowing; 300 kg N ha⁻¹). Under water–fertilizer integration, N was applied at five rates (0, 120, 180, 240, and 300 kg N ha⁻¹, N applied at sowing, jointing, and tasseling and ratio of 1:1:1; designated WN₀, WN₁₂₀, WN₁₈₀, WN₂₄₀, and WN₃₀₀, respectively). The leaf area index and dry matter accumulation increased with increasing N application rate, with a slower rate of increase when N application rate ≥180 kg N ha⁻¹. Compared with CK, the GY of WN₃₀₀, WN₂₄₀, WN₁₈₀, and WN₁₂₀ was not significantly different,but WN₁₂₀ significantly decreased by 7.16% and 5.47% than WN₂₄₀ and WN₃₀₀.The evapotranspiration,irrigation amount,and N application rate in WN₁₈₀ were 9.86%–16.40%, 47.11%–52.23%, and 40% lower,respectively,than in CK,while the water use efficiency and N partial factor productivity was 3.38%–15.14% and 32.04%–60.43% higher.Thus,application of 180 kg N ha⁻¹ with water–fertilizer integration can achieve high GY and improve resource–use efficiency.

摘要

为提高夏玉米的产量（GY）和水氮（N）利用效率，采用微喷灌水肥一体化进行了为期2年的田间试验。对照采用地表灌溉和施氮方法（CK，播种时灌溉；300 kg N ha ^-1）。在水肥一体化条件下，N 以 5 种比例施用（0、120、180、240 和 300 kg N ha ^-1，N 在播种、拔节和抽穗时施用，比例为 1:1:1；指定为 WN ₀ , 西北部₁₂₀ , 西北部₁₈₀ , 西北部₂₄₀和 西北部₃₀₀， 分别）。叶面积指数和干物质积累随着施氮量的增加而增加，当施氮量≥180 kg N ha ^-1时增加速度较慢。与CK相比，WN ₃₀₀、WN ₂₄₀、WN ₁₈₀和WN ₁₂₀的GY差异不显着，但WN _{120比WN 240}和WN ₃₀₀显着降低7.16%和5.47% 。蒸散量、灌溉量和N WN ₁₈₀的应用率分别比CK低9.86%~16.40%、47.11%~52.23%和40%，而水分利用效率和N偏生产力分别高3.38%~15.14%和32.04%~60.43%。因此， 180 kg N ha ^-1水肥一体化施用可实现高GY，提高资源利用效率。