29种农药对家蚕的急性毒性评价

An Evaluation on Acute Toxicity of 29 Pesticides to Bombyx mori

采用食下毒叶法,测定29种农药对家蚕的急性毒性,结果表明:阿维菌素、多杀菌素、氯氰菊酯.毒死蜱和吡虫啉对家蚕96 h的LC50分别为0.002 0、0.089 1、0.214 5和0.272 9 mg/L,属剧毒级农药;阿维菌素.苏云金杆菌、丁硫克百威、敌百虫、除虫菊素.苦皮藤素、丙溴磷、苏云金杆菌.毒死蜱和烟碱对家蚕96 h的LC50分别为0.692 1、0.769 6、0.850 2、0.744 9、2.513 4、1.732 7和7.260 4 mg/L,属高毒级农药;其余药剂均属中、低毒级农药。以上剧毒级或高毒级的农药应当禁止在蚕区使用。吡蚜酮对家蚕的毒性低,但在蚕区是否能使用低毒级农药,还须考虑药剂的残毒期、慢性毒性和传染性等因素。

The acute toxicity of 29 pesticides to silkworm,Bombyx mori,was evaluated in laboratory by using the leaf dipping method.The results indicated that LC50 of abamectin,spinosad,cypermethrin·chlorpyrifos,and imidacloprid was 0.002 0,0.089 1,0.214 5,and 0.272 9 mg/L respectively,being pesticides of virulent toxicity grade.The LC50 of abamectin·Bacillus thuringiensis,carbosulfan,trichlorfon,pyrethrins·celastrusangulatus,profenofos,Bacillus thuringiensis·chlorpyrifos,and nicotine was 0.692 1,0.769 6,0.850 2,0.744 9,2.513 4,1.732 7,7.260 4 mg/L respectively,being pesticides of high toxicity grade.All the other pesticides were of moderate or low toxicity grade.Pesticides of virulent and high toxicity grade should be forbidden to use in silkworm rearing areas.Pymetrozine is of low toxicity grade.Yet the residual toxicity period,chronic toxicity and infectivity should be considered if pesticides of low toxicity grade are to be used in silkworm rearing areas.