化学药剂增效配方对辣椒疫病的控制作用

Control effect of chemical synergistic formula on pepper phytophthora blight

采用菌丝生长速率法测定了9种化学药剂对辣椒疫病菌的毒力,其中烯酰吗啉(EC50=0.48μg/mL)和氟吡菌胺(EC50=0.32μg/mL)的毒力最强。共毒系数测定结果表明,百菌清∶氟吡菌胺为1∶9和烯酰吗啉∶氟吡菌胺为2∶8时,表现出增效作用,分别配制成20%百·氟悬浮剂和20%烯·氟悬浮剂。盆栽试验结果表明,处理后10 d,20%烯·氟悬浮剂2 000倍对辣椒疫病的防治效果在96%以上;20%百·氟悬浮剂1 000倍对辣椒疫病的防治效果为75%左右。20%烯·氟悬浮剂2 000倍对辣椒疫病的防治效果与对照药剂50%烯酰吗啉可溶性粉剂1 000倍液的防治效果相当,显著高于68.75%银法利悬浮剂1 000倍的防治效果。

The toxicity of 9 fungicides against pepper phytophthora blight were tested with mycelium growth rate method. The results indicated that the highest toxicity of fungicides were dimethomorph（EC50=0.48 μg/mL） and fluopicolide（EC50=0.32 μg/mL）. The synergisms were chosen by the method of co-toxicity coefficience, and the ratios were that chlorothalonil /fluopicolide（1∶9） and dimethomorph/fluopicolide（2∶8）. The 20% suspension concentrates（SC） were prepared with best synergism ratio. After 10 d treatment, the pot experiment reuslts showed that the control effect of dimethomorph/fluopicolide 20% SC diluted 2 000 times was up to 96%; the control effect of chlorothalonil/fluopicolide 20% SC diluted1 000 times was 75%. Statistic analysis indicated that the control effect of dimethomorph/fluopicolide 20% SC diluted 2 000times was equal to dimethomorph 50% SC diluted 1 000 times and higher than that of 68.75% Infinito SC diluted 1 000times significantly.