多菌灵、好力克及其复配对小麦赤霉病的防治效果

小麦扬花期喷施多菌灵是生产上防治小麦赤霉病的主要措施,为了延缓病原菌对多菌灵的抗药性,对不同作用方式的化学药剂混配及其对小麦赤霉病的防治效果进行研究。研究选用95%多菌灵原药和95%戊唑醇原药测定对小麦赤霉病菌菌丝生长的抑制作用,并将两者按照Horsfall方法进行不同比例的混配,对毒性比率较高的混配比例采用共毒系数方法验证其增效作用。结果表明多菌灵与戊唑醇按EC50剂量20:80的比例混配具有增效作用,在温室盆栽试验测试中50%多菌灵可湿性粉剂、43%好力克悬浮剂以及两者混剂的防效都达到了85%以上,而且混剂1000倍防效显著高于多菌灵800倍,可用于小麦赤霉病的防治。

Control Effect of Carbendazim, Horizon and its Mixture on the Controlling of Fusarium Head Blight

Spraying Carbendazim in the flowering season is the main way for controlling Fusarium head blight. In order to reduce the resistance of pathogen to Carbendazim, mixture of fungicides with different action mode and their control effect to Fusarium head blight is studied. In this study Carbendazim and Tebuconazole were tested for the inhibiting of mycelium growth of Fusarium graminearum in vitro. Carbendazim and Tebuconazole were further studied in a form of mixture by Horsfall method. The mixture proportion, which had higher toxicity ratio, was validated for its synergistic effect by CTC method. Results showed that the proportion of Carbendazim and Tebuconazole 20:80 based on each EC50 dose had synergistic effect. Further greenhouse test indicated that the control efficacy of Carbendazim, Horizon and the mixture were all above 85%. Moreover the control efficacy of the mixture at 1000 times dilution was significantly better than that of Carbendazim at 800 times dilution. The mixture had much potential for the control of Fusarium head blight in the future.