为明确异菌脲在玉米拟轮枝镰孢穗腐病防治中的效果，采用菌丝生长速率法测定异菌脲等5种杀菌剂对拟轮枝镰孢的室内毒力，并筛选新组合苯醚甲环唑与异菌脲的最佳复配比例；田间评价新型复配药剂12%苯醚·异菌脲悬浮剂对拟轮枝镰孢穗腐病的防效。室内毒力测定表明，三唑类杀菌剂氟环唑、丙环唑、苯醚甲环唑对拟轮枝镰孢的EC₅₀为0.019～0.045 mg/L，氰烯菌酯和异菌脲的EC₅₀分别为3.130 mg/L和4.312 mg/L；苯醚甲环唑与异菌脲按有效质量比1∶3复配表现出增效作用。田间试验表明，12%苯醚·异菌脲悬浮剂可显著降低拟轮枝镰孢穗腐病的发病率和发病面积占比，对拟轮枝镰孢穗腐病的防治效果为66.95%，单穗增产率为13.34%。研究表明，异菌脲对拟轮枝镰孢生长有一定抑制作用，12%苯醚·异菌脲悬浮剂具有防病减损效果，可用于拟轮枝镰孢穗腐病的田间防控。

To clarify the control effect of iprodione on maize ear rot caused by Fusarium verticillioides, the indoor toxicity of five fungicides including iprodione against F. verticillioides was tested by the mycelial growth rate method, and the optimal combination ratio of difenoconazole and iprodione was screened. Additionally, the control efficacy of the new compound agent(12% difenoconazole-iprodione suspension concentrate) against F. verticillioides ear rot was evaluated in field. Indoor toxicity tests showed that the EC₅₀ values of the triazole fungicides(epoxiconazole, propiconazole, and difenoconazole) against F. verticillioides were 0.019-0.045 mg/L, and the EC₅₀ values of phenamacril and iprodione were 3.130 mg/L and 4.312 mg/L respectively. The compounding of difenoconazole and iprodione at a mass ratio of 1∶3 exhibited a synergistic effect. Field trial indicated that 12% difenoconazole-iprodione suspension concentrate significantly reduced the incidence and proportion of diseased area caused by F. verticillioides ear rot, with a control effect of 66.95% on it and a yield increasing rate of 13.34%. The above results showed that iprodione has a certain inhibitory effect on the F. verticillioides, and 12% difenoconazole-iprodione suspension concentrate has the effects of preventing F. verticillioides ear rot and reducing maize loss in the field.

S435.131

河北省农林科学院科技创新专项(2022KJCX-ZBS-2)、国家玉米产业技术体系项目(CARS-02)