Bioactivity of cantharidin against eleven pests | 斑蝥素对11种害虫的杀虫活性

chinois. 明确天然产物斑蝥素的杀虫谱和作用方式。采用不同生测方法，测定斑蝥素及1.0%斑蝥素乳油对11种害虫的室内毒力，观察了家蝇成虫的中毒症状。斑蝥素对家蝇成虫具有一定的胃毒作用，其48，72 h的胃毒LC50分别为781.90，397.23 mg/L，无触杀、熏蒸作用，其中胃毒作用较缓慢，处理约18 h后才表现出明显的中毒症状；对玉米象成虫的48 h胃毒LC50和触杀LD50分别为373.17 mg/L和0.36 μg/虫，无熏蒸活性；对大叶黄杨斑蛾4龄幼虫的24，48 h触杀LD50分别为0.084，0.049 μg/虫；1.0%斑蝥素乳油对烟蚜、菊姬长管蚜、桃粉蚜、萝卜蚜和月季长管蚜5种蚜虫无翅成蚜的12 h触杀LC50分别为19.52，15.84，16.63，25.94，26.20 mg/L;1.0%斑蝥素乳油对朱砂叶螨、麦圆蜘蛛和山楂叶螨成螨的12 h触杀LC50分别为8.26，13.38，8.46 mg/L。斑蝥素对多种害虫均具有不同程度的毒杀作用，其主要作用方式为触杀和胃毒。

anglais. The study was done in order to ascertain the further insecticidal spectra and mode of action of the natural product, cantharidin. Bioactivity of cantharidin was tested against eleven pests by different laboratory bioassay methods, and the toxic symptom of adult housefly was observed. Cantharidin had certain stomach action against housefly adults, but it had no contact or fumiganting action. Its LC50 values of stomach toxicity to the housefly adults were 781.90 mg/L(48 h) and 397.23 mg/L(72 h), and the stomach toxicity of cantharidin on adult housefly was slow, because the housefly did not show toxic symptom until 18 h after treatment. Its LC50 value of stomach toxicity and LD50 value of contact toxicity against adult corn weevils after 48 h were 373.17 mg/L and 0.36 μg/insect, respectively. Its LD50 values of contact toxicity against fourtn instar larvea of Pryeria sinica M were 0.084 μg/insect(24 h) and 0.049 μg/insect(48 h). The LC50 values for contact toxicity of 1.0% cantharidin EC to Myzus persicae, Macrosiphoniella sanborni, Hyaloptera amygdali, Lipaphis erysimi and Macrosiphum roswomm after 12 h were 19.52, 15.84, 16.63, 25.94 and 26.20 mg/L, respectively. The LC50 values for contact toxicity of 1.0% cantharidin EC to Tetranychus cinnabarinus, Penthaleus major and Tetranychus viennensis after 12 h were 8.26, 13.38 and 8.46 mg/L, respectively. It is clear from the mentioned facts above that the cantharidin has insecticidal effect on different kinds of pests to different degrees, and its main mode of action is contact as well as stomach toxicity.