Under the current situation, in which the yield of dryland maize is significantly increased and the simplified cultivation measures are gradually adopted, field plots test were conducted to study the effect of the fertilizer on maize growth and WUE in the three-consecutive-year with different precipitations. The results indicated that the growth of maize was inhibited when excessive fertilizer was applied in the dryland maize at a time, especially during a particular year when the soil moisture was in a bad condition or the rainfall was less was maize's growth season. However, this inhibited effect could be gradually reduced with the advance of maize growth process. Methods such as deep fertilization with different depths at a time and the fertilization of slow-release fertilizer should be adopted in the production in order to alleviate the adverse factors. During the normal precipitation year with the pre-sowing soil moisture in a good condition, the application of fertilizer could apparently increase the production and improve the effect of WUE. Compared to the yield with no fertilization, the economic yields of low fertilization, middle fertilization and high fertilization increased by 31%, 36% and 63%, separately. The WUE of low fertilization, middle fertilization and high fertilization increased by 27. 7%, 29. 8% and 53. 2% separately. However, in the year of partial drought with better pre-so-wing soil moisture or in the wet year with bad pre-sowing soil moisture, the effect mentioned above was not obvious. Sometimes that may even lead to negative effects. In 2008, the production of high fertilization treatment was apparently 6. 3% lower than that of middle fertilization. In the dryland agricultural production, we should know the condition of pre-sowing soil moisture very well and predict the precipitation. Based on that, "the amount of water determines the amount of fertilization and the amount of water determines the yield. " According to this, water and fertilizer coupling will be well planed in the agricultural production.%在旱地玉米产量大幅提升以及逐步采用简化栽培措施的生产形势下,采用田间小区试验的方法,研究连续3 a不同降水年型施肥量对旱地玉米生长及水分利用效率的影响.结果表明,一次底施过多肥料会抑制玉米的生长,特别是在底墒较差或生育期降水偏少的年份,但这种抑制作用会随着玉米生育进程的推进逐步减轻.生产中应采用一次性分层深施缓释或长效肥的施肥方式来减轻这种不利因素.在底墒较好的降水正常年份,施肥具有明显的增产和提高水分利用效率(WUE)的作用,低肥、中肥和高肥的经济产量分别较不施肥增加31％、36％和63％,水分利用效率分别增加27.7％、29.8％和53.2％.但在底墒较好的偏旱年或底墒很差的丰水年,施肥的上述作用不明显,有时反而会出现负效应,2008年高肥处理产量反而显著低于中肥,较中肥低6.3％.旱地农业生产中应在已知底墒的基础上,通过预测降水量,“以水定肥、以水定产”,合理实行水肥耦合运筹.
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