密达利杀灭山丘钉螺效果和鱼毒试验

目的在山丘地区观察密达利喷洒灭螺效果及对鱼类的毒性。方法选择钉螺孳生的山丘地区苗木地为灭螺试验现场,分为密达利试验组、氯硝柳胺乙醇胺盐对照组和空白对照组,观察灭螺效果;选择3口体积相同的水塘为鱼毒试验现场,分为密达利高、低浓度试验组和清水对照组进行鱼类毒性试验比较。结果施药后3、7、15 d,密达利组活螺平均密度为0.49、0.42、0.17只/0.1 m^2,氯硝柳胺乙醇胺盐组为0.90、0.60、0.15只/0.1 m^2,空白对照组为5.40、9.05、3.90只/0.1 m^2,3、7、15 d时,活螺密度下降率密达利组为85.92%、50.55%和87.93%,氯硝柳胺乙醇胺盐组为67.03%、95.11%和91.76%,两组活螺平均密度下降率差异无统计学意义（P〉0.05）;施药后3,7 d和15 d,密达利组钉螺校正死亡率分别为89.76%、87.98%和94.10%,氯硝柳胺乙醇胺盐组为89.70%、83.22%和94.72%,空白对照组为9.24%、9.50%和15.21%,密达利组与氯硝柳胺乙醇胺盐组差异无统计学意义（P〉0.05）,与空白对照组差异有统计学意义（P〈0.05）。密达利高、低浓度试验组和清水对照组鱼类死亡率均为0。结论山丘地区旱地使用密达利在短期内具有较好的杀螺效果,对鱼类低毒。

Mollusicidal effect and toxicity to fish with META-Li in field

The mollusicidal effect and toxicity to fish with META-Li in field were tested in mountain areas in Zhejiang Province. The snail control test, which had 3 groups including a META-Li group, niclosamide group and control group, were performed by the spraying method. The adjusted mortalities of snails in the META-Li group on the 3rd, 7th and 15th day were 89.76% , 87.98% and 94.10% , respectively, in the niclosamide group were 89.70% , 83.22% and 94.72% , respectively .and there was no significant difference between the two groups ( P > 0.05), but they were decreased obviously compared with the control group, which were 9.24% , 9.50% and 15.21% , respectively(P <0.05). The toxicity test to fish with META-Li included 3 groups, namely a high concentration META-Li group, low concentration META-Li group and control group, and none fish was dead. It is suggested META-Li has low toxicity to fish, and is suitable to snail control in aquiculture areas.