3种杀幼剂对蚊幼的现场控制效果研究

Efficacy of three kinds of insecticides against mosquito larvae in the field

目的探讨3种杀幼剂对蚊幼的现场控制效果,为世博会期间蚊虫孳生地控制提供药物和技术储备。方法选择雨水井、水池、沟渠等为现场测试场所,根据面积或体积布施不同剂量的药物,观察施药后蚊幼密度下降情况并计算其持效期。结果 1.0~1.5 mg/L甲基嘧啶磷对雨水井中白纹伊蚊的控制效果达14 d以上,2.0~2.5 mg/L可维持21 d以上。1.0 mg/L甲基嘧啶磷对沟渠中三带喙库蚊的控制效果达10 d,1.5~2.5 mg/L可维持12 d。1.0~1.4 mg/L毒死蜱能有效控制雨水井中的白纹伊蚊和沟渠中的淡色库蚊,持效期长达35 d或更长,0.6~0.8 mg/L达14~21 d。0.4~0.8 mg/L 1%双硫磷能有效控制雨水井中的白纹伊蚊和沟渠中的淡色库蚊,但持效期较短,仅为10~14 d;1.2 mg/L为21 d。现场实验中,0.8 mg/L双硫磷对三带喙库蚊有14 d的控制效果,1.0~1.5 mg/L的控制持效期则为21 d。结论 3种药物均对白纹伊蚊、淡色库蚊、三带喙库蚊有较好的控制效果,持效期为毒死蜱〉双硫磷〉甲基嘧啶磷。相同药物对不同环境下不同蚊虫的控制效果有一定差异,因此须根据水体流动、水质状况等合理使用杀幼剂。

Objective To evaluate the efficacy of three kinds of insecticides for controlling mosquito larvae in the field.Methods Taking the gully trap,pool and ditch as the test sites,and the insecticides were used according to the difference of areas and volume,and then the change of mosquito larvae density was observed and the validity periods was evaluated.Results The validity period of pirimiphos-methyl to Aedes albopictus in the field was 14 d at 1.0-1.5 mg/L,and more than 21 d at 2.0-2.5 mg/L.For Culex pipiens pallens,its control efficacy reached 21 d at 1 mg/L,and 12 d at 1.5-2.5 mg/L.The control efficacy of chlorpyrifos to Ae.albopictus and Culex tritaeniorhynchus was 35 d at 1.0-1.4 mg/L,and it reached 14-21 d at 0.6-0.8 mg/L.The validity period of temephos to Ae.albopictus and Cx.pipiens pallens was only 10-14 d at 0.4-0.8 mg/L,and 21 d at 1.2 mg/L.In the field,the control efficacy to Cx.tritaeniorhynchus reached 14 d at 0.8 mg/L,and 21 d at 1.0-1.5 mg/L.Conclusion Three kinds of insecticides have good control efficacy to mosquito larvae in the field.The order of persistent period is chlorpyrifos temephos pirimiphos-methyl.The control efficacy of same insecticides to different mosquitoes in different environment is very different,and the insecticides should be used rationally according to water quality and water stream.