Bti微胶囊制剂防治蚊虫的研究

Studies on the Larvicidal Efficacy of Bacillus thuringiensis var.israelensis Encapsulated Formulation against Mosquitoes

苏云金杆菌以色列变种（Ｂｔｉ）广泛应用于现场控制蚊幼虫，取得良好的杀灭效果。但由于现有剂型持效期短，限制了更大规模的应用，也给储存运输带来麻烦。本研究主要在室内评价了不同浓度Ｂｔｉ微胶囊制剂对中华按蚊、淡色库蚊和白纹伊蚊幼虫的效果及持效。结果表明，该种制剂有一定的漂浮性，在水内稳定性较好，具较长的持效期，１．２５ｐｐｍ浓度４周内对白纹伊蚊幼虫仍有较理想的杀灭效果。推荐防治中华按蚊、淡色库蚊和白纹伊蚊的需要剂量分别为０．２５、１．２５和０．０５ｐｐｍ，每２～３周施药１次。

Bacillus thuringiensis var.israelensis(short for Bti) has been extensively used in the control of mosquito larvae with excellent results.But the short residual effect of common Bti formulations limited the larger scale application in the field and brought up the inconvenience in.the transportation and storage as well.This study focused on the laboratory evaluation of larvicidal efficacy and persistence of Bti encapsulated formulation,at different dosages,against larvae of An. sinensis Cx.pipiens pallens and Ae.albopictus.The results indicated that the formulation is of certain floating ability and is stable in aquatic environment,with the long residual larvicidal activities.At the dosage of 1.25 ppm,the formulation resulted in excellent larvicidal efficacy against Ae.albopictus larvae within 4 weeks after appli cation.It is recommended that 0.25ppm,1.25ppm and 0.05ppm be required for the control of An.sinensis,Cx.pipiens pallens and Ae.albopictus larvae respectively,to be applied at 2-3 weeks interval.