水氮耦合对春小麦干物质累积与植株氮素转运的影响

为明确甘肃中部地区春小麦合理的施氮水平和灌水量,以陇春27为研究对象,以灌水量1000（W1）、2000（W2）和3000m³/hm²（W3）]为主区,施氮量0（N0）、80（N1）、160（N2）和240kg/hm²（N3）]为副区,研究水氮对小麦干物质累积、氮含量、氮素累积及产量的影响。结果表明,不同施氮量和灌水量对小麦干物质累积量、氮累积量、籽粒产量及氮转运均有显著影响,且存在互作效应;各生育期小麦干物质累积量随灌水量与施氮量的增大呈增大趋势,灌水量对干物质累积量影响大于施氮量;茎和叶氮含量随施氮量增大而增大,氮含量为籽粒>叶>颖壳>根>茎,灌水处理对小麦营养器官氮含量影响小于施氮处理;随灌水量与施氮量增大,小麦各器官氮累积量呈先增大后减小趋势;籽粒氮累积量与产量以W2N2处理最大,适宜的水氮供给有利于干物质从营养器官向生殖器官转移,从而提高籽粒产量和氮素生产效率。综上,灌水量与施肥量分别在2000m³/hm²和160kg/hm²时有利于小麦生产。

Effects of Irrigation and Nitrogen Application on Dry Matter Accumulation and Nitrogen Transport of Spring Wheat

In order to establish an optimum combination of water and nitrogen for spring wheat in central Gansu province, an experiment was conducted as a completely randomized split-plot design, with local wheat cultivar (Longchun 27) as the experimental material, taking irrigation 1000 (W1), 2000 (W2) and 3000m³/ha (W3)] as main plot treatment and N-supply as split-plot treatment 0 (N0), 80 (N1), 160 (N2) and 240kg/ha (N3)]. The effect of intermittent irrigation and nitrogen on dry matter accumulation, nitrogen content, nitrogen accumulation, and yield of spring wheat was investigated. The results showed dry matter accumulation, nitrogen accumulation, nitrogen transport and yield were significantly affected by irrigation treatment, N rate and irrigation treatment × N rate interaction. The increase in irrigation and nitrogen led to an initial increase in dry matter accumulation in wheat. N fertilizer had little impact, and water?s contribution to dry matter accumulation more significant. The nitrogen contents of stems and leaves increased with the amount of nitrogen. The order of nitrogen content was grain > leaf > glume > root > stem, the order of irrigation and nitrogen rate effect on nitrogen content in vegetative organs was nitrogen > irrigation. Nitrogen content in vegetative organs increased first and then decreased with the increase of nitrogen rate and irrigation amount, the maximum grain yield were observed in W2N2 treatment. Suitable water and nitrogen condition was beneficial to the dry matter transfer from vegetative organs to reproductive organs, raise grain production efficiency, nitrogen production efficiency and yield of spring wheat. Thus, the irrigation schedule (2000m³/ha) and optimized nitrogen (160kg/ha) can promote the wheat growth.