吡唑醚菌酯与10种杀菌剂混配对小麦赤霉病菌的毒力测定及增效研究

Toxicity Determination and Research on Synergistic Effect of Mixture of Pyraclostrobin and 10 Fungicides Against Fusarium graminearum

小麦赤霉病是小麦生产中发生危害最主要的病害之一,不仅降低产量,而且病原菌产生的毒素影响人畜健康,目前生产上以化学防治为主。为有效降低抗药性风险,筛选不同作用机制的高效杀菌剂,给农业生产提供科学的理论依据,本文采用生长速率法测定了11种杀菌剂对小麦赤霉病菌(Fusarium graminearum)的毒力及吡唑醚菌酯与其他10种杀菌剂按质量比1:1混配的毒力。结果表明,单剂毒力测定中咪鲜胺和戊唑醇最优,EC50分别为0.0435和0.1189;而三唑醇、甲基硫菌灵、三唑酮3种单剂效果较差,EC50分别为8.6158、13.0761和17.9022;其它6种杀菌剂的EC50在1左右,抑菌效果较好。复配试验中,吡唑醚菌酯和氟环唑、烯唑醇质量比1∶1复配具有明显增效作用,而其它复配试验无明显增效作用。

Fusarium graminearum is the most common causal agent of Wheat Scab, a devastating disease of wheat around the world. In addition to huge grain yield and quality losses, grain contamination with mycotoxins produced by F.graminearum continues to attract our concern. Application of chemical agents remains critical for the disease control. In order to reduce the risk of drug resistance and screen high-efficiency fungicides and provide scientific theoretical basis for agriculture production, the toxicity of 11 fungicides against F.graminearum and synergistic effect of pyraclostrobin mixed with other 10 fungicides at a mass ratio of 1∶1 were determined by growth rate method. The results showed that the prochloraz and tebuconazole were optimal in a single-dose virulence assay with EC 50 of 0.0435 and 0.1189, respectively. However, the effects of triadimenol, thiophanate-methyl, and triadimefon were poor, with EC 50 of 8.6158, 13.0761 and 17.9022, respectively. The EC 50 of the other 6 fungicides was about 1 and the antibacterial effect was better. In the compounding test, the 1∶1 compounding of pyraclostrobin with epoxiconazole and diniconazole respectively had a significant synergistic effect, while there was no significant synergism in the othercombinations.