施氮和拔节期测墒补灌对冬小麦产量和氮素吸收的影响

摘要

[目的]研究施氮量和拔节期不同测墒补灌量对冬小麦的产量及构成因子、植株氮素吸收的影响。[方法]采用土壤目标相对含水量和施氮量3×3完全均衡方案和裂区设计，土壤目标相对含水量设3个水平，分别为拔节期60%（W1）、70%（W2）和80%（W3），施氮量设3个水平，分别为施纯氮0 kg/hm2（ N0）、195 kg/hm2（N195）和255 kg/hm2（N25），以周麦18为供试材料。[结果]拔节期测墒补灌和施氮对小麦产量及其构成因子、植株氮素积累量均有显著或极显著影响。补灌量和施氮量对穗数、穗粒数、千粒重、产量和植株氮积累量的交互效应均达显著或极显著水平，在不同水氮处理组合中，以 W2 N195产量最高，而以 W1 N25产量最低。[结论]随着补灌量的增加，相应地降低氮肥用量有利于增加穗数、穗粒数、产量和植株氮素积累量，降低施氮对千粒重的负效应。%Objective This study aimed to determine the effects of supplemental irri-gation on yield and nitrogen uptake in winter wheat. [Method] Three supplemental ir-rigation levels were set based on the target soil contents of 60%, 70% and 80%) at jointing stage of wheat. Moreover, three nitrogen levels (0, 195 and 255 kg/hm2) were designed. The experimental plots were arranged fol owing a split-plot design. Zhoumai 18 was selected as the experimental material. [Result] Supplemental irriga-tion and nitrogen application in combination had significant or extremely significant effects on yield, yield components and nitrogen uptake in winter wheat. The interac-tion between irrigation and nitrogen fertilization had significant or extremely signifi-cant influence on the number of ears, number of grains per ear, 1 000-grain weight, grain yield and nitrogen accumulation in winter wheat. Under different combinations of supplemental irrigation and nitrogen application, the maximum yield of winter wheat was obtained at W2 N195, while the minimum at W1 N255. [Conclusion] With the increase of irrigation, negative effect of nitrogen on number of ears, number of grains per ear, 1 000-grain weight, grain yield and nitrogen accumulation decrease under lower nitrogen application rate.