为探明250 g/L 丙环唑EC对小麦条锈病和白粉病的防治效果及合理使用剂量，采用测报调查、随机区组设计和统计分析方法，开展了250 g/L 丙环唑EC防治小麦条锈病和白粉病田间药效试验示范。结果表明，在春季条锈病流行期间，用250 g/L 丙环唑EC 600 mL/hm2、450 mL/hm2和300 mL/hm2连续施用2 次，对小麦条锈病有很好的防治效果，药后8 天和18 天防效均在98%以上，且各使用剂量之间防效差异不显著。对小麦白粉病亦有很好的防治效果，药后8 天防效均达100%，但持效期仅10 天左右，药后18天，防效显著下降，用250 g/L丙环唑EC 600 mL/hm2防治效果仅78.4%，用250 g/L丙环唑EC 450 mL/hm2及以下剂量，防治效果在41%以下。在小麦条锈病和白粉病发生不重情况下，使用最佳剂量为300~450 mL/hm2，有利于减少农药使用量和农残污染，节约防治成本。但在白粉病偏重及以上发生和条锈病混发麦地，须连续2 次用250 g/L 丙环唑EC 600 mL/hm2，以确保防治效果。利尔化学股份有限公司和先正达苏州作物保护有限公司生产的250 g/L 丙环唑EC，用量相同防效没有差异，且国内和国外公司生产的250 g/L 丙环唑EC质量没有差异。从节约防治成本考虑，最好用国内利尔化学股份有限公司生产的250 g/L丙环唑EC。

In order to explore the effect of 250 g/L propiconazole EC on wheat stripe rust and powdery mildew and the reasonable application dosage, a field demonstration experiment was carried out through the method of forecast and investigation, randomized block design and statistical analysis. The results showed that during the spring wheat stripe rust epidemics, the two- time continuous application of 600 mL/hm2, 450 mL/hm2 and 300 mL/hm2 of 250 g/L propiconazole EC had a good control effect on wheat stripe rust. The control effects after 8 days and 18 days were still above 98% and the difference among different application dosages was not significant. Also there was a good control effect on wheat powdery mildew. After 8 days, the control effect could reach 100% but the effect could only be kept for about 10 days. After 18 days, the control effect of 250 g/L propiconazole EC significantly decreased, the effect of 600 mL/hm2 was only 78.4%, and the effect of 450mL/hm2 or lower was under 41% . In the case of not serious wheat stripe rust and powdery mildew, the optimal application dosage was 300-450 mL/hm2, which could reduce pesticide usage and pollution, and also save the control cost. Under heavy outbreak of powdery mildew and in the mixed incidence area of the two diseases, the 250 g/L propiconazole EC application should be 600 mL/hm2 for two times to ensure the control effect. There was no difference between 250 g/L propiconazole EC produced by Lier Chemical Co., Ltd. and Syngenta Suzhou crop protection Co., Ltd. in control effect with the same dosage, and the domestic production and foreign production did not differ in quality. For saving the cost of prevention and control , it is better to use 250 g/L propiconazole EC produced by Lier Chemical Co., Ltd.