通过优化天水地区冬油菜施肥方案，在不降低产量和产出效益的前提下，明确减轻化肥施用对环境的污染的最佳施肥量。以天油15号为指示品种，在武山县设常规施肥、常规施肥减量15%、减量25%、减量30%、减量50%+有机肥共5个处理，观察化肥减量对冬油菜生育期、主要农艺性状、产量及效益的影响。结果表明，化肥减量15%～50%对天油15号生育期基本不影响，但其主要农艺性状表现均以化肥减量25%处理最好，减量30%次之；减量25%和30%处理均较常规施肥增产，但增产不显著；常规施肥减量30%的产投比最高，减量25%次之。综上所述，相比常规施肥，化肥减量25%～30%既能保证冬油菜高产，又能减少投入成本，获得较好的收益。

Optimizing the fertilization mode for winter rapeseed in Tianshui can reduce environmental pollution caused by fertilizer application without reducing yield and output benefits. An experiment in field was conducted in Wushan County using variety Tianyou 15 to observe the effects of chemical fertilizer reduction on growth period, main agronomic traits, yields and benefits of oilseed rape, which included 5 treatments, i.e., conventional fertilization amount, 15%, 25%, 30% reduction based onconventional fertilization amount, respectively, and 50% reduction plus organic fertilizer. The results showed 15% to 50% reduction in conventional fertilizer application had little effect on the growth period. The main agronomic traits were best treated with 25% reduction in chemical fertilizer amount, followed by 30% reduction; and both the 25% and 30% reduction treatments increased yield compared to conventional fertilization, but the increase was not significant. The output-input ratio of 30% chemical fertilizer reduction treatment was highest in all treatments, followed by the 25%. Based on the above results, it was recommended to reduce the amount of chemical fertilizers by 25% to 30% of conventional fertilizer application in production, which could ensure high yield of winter oilseed rape to reduce costs and obtain better returns.

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天水市科技支撑计划(2021-NCK-2217)。