茚虫威及其复配剂对家蚕的毒性和安全性评价

Toxicity and Safety Evaluation of Indoxacarb and Its Compound Agent on Silkworm Bombyx mori

茚虫威及其复配剂是防治稻纵卷叶螟和蔬菜鳞翅目害虫的重要农药品种,为明确此类农药对家蚕的毒性,在蚕区其他农作物害虫防治时避免和减轻对养蚕生产的安全风险,测定了茚虫威单剂和3种复配剂对家蚕的经口急性毒性和熏蒸毒性,以及在桑叶上的残留毒性和内吸传导毒性。结果显示,30%茚虫威悬浮剂、15%多杀·茚虫威悬浮剂、16%甲维·茚虫威悬浮剂、8%阿维·茚虫威水分散粒剂对3龄起蚕添毒24 h的LC50分别为0.3604 mg/L、0.0482 mg/L、0.0071 mg/L、0.0095 mg/L,对家蚕均为剧毒级;茚虫威单剂和3种复配剂在试验浓度下对家蚕无熏蒸毒性,在桑叶上无内吸传导作用;按茚虫威单剂和3种复配剂防治稻纵卷叶螟的推荐使用浓度药液直接喷酒桑叶,对3龄起蚕的残毒期均>60 d,在桑叶上的残毒期很长。结果表明,茚虫威单剂和3种复配剂对养蚕生产的安全性风险很高。依据试验结果建议:30%茚虫威悬浮剂、15%多杀·茚虫威悬浮剂、16%甲维·茚虫威悬浮剂、8%阿维·茚虫威水分散粒剂严禁在桑园中使用,桑园附近大田中使用此类农药应注意间隔距离和施药方法,防止药液飘移而污染桑园。

The indoxacarb and its composite agent are an important pesticides to control rice leaf roller and Lepidoptera pests of vegetables.Acute oral toxicity and fumigation toxicity of indoxacarb agent alone and 3 types of its composite agents were tested by silkworm larvae,and studies on their residual toxicity in mulberry leaves and translocated toxicity were also carried out so as to avoid or reduce cocoon production risk when they are used for pest control of other crops in the sericulture region.The results showed that LC50 of indoxacarb 30%SC,15%kill-indoxacarb suspension,16%Emamectin-indoxacarb suspension,8%abamectin and indoxacarb water dispersible granule were 0.3604 mg/L,0.0482 mg/L,0.0071 mg/L,and 0.0095mg/L respectively by oral administration on 3rd instar silkworm larvae for 24 h,indicated that they are all highly toxic to silkworm larvae.Indoxacarb agent alone or the other 3 types of its composite agents had no fumigation toxicity on silkworm larvae at the tested concentrations,and also without suction conduction effect on mulberry leaves.The residual duration of indoxacarb agent alone or the other 3 types of its composite agents to 3rd instar silkworm larvae were>60 d if they were sprayed on mulberry leaves by the recommended concentration for controlling rice leaf roller.The results showed that indoxacarb agent alone or the other 3 types of its composite agents had very high risk on cocoon production.Based on the experimental results,the authors suggest:indoxacarb 30%SC,15%kill-indoxacarb suspension,16%Emamectin-indoxacarb suspension,8%abamectin and indoxacarb water dispersible granule should be prohibited to be used in mulberry fields,and pay attention to the distances and application method if they were used nearby mulberry fields so as to prevent its liquid drift and pollution on mulberry leaves.