【摘要】 对昆虫天然产物斑蝥素(Cantharidin,C10H12O4)和斑蝥素类似物去甲斑蝥素(Demethylcantharidin)的杀虫活性及其作用方式进行了生物测定。结果表明:斑蝥素和去甲斑蝥素对菜蛾Plutella xylostellaL.幼虫有较强的胃毒和拒食作用。试虫胃毒中毒症状主要为活动能力下降,逐渐死亡,虫体前中部发黑。斑蝥素和去甲斑蝥素胃毒致死量分别为8.69μg/g体重和819.5μg/g体重;选择性拒食中浓度分别为2.67mg/L和20.46mg/L;非选择性拒食中浓度分别为0.69mg/L和7.63mg/L。前者分别高于后者94.4倍、7.66倍和11.06倍。助剂ZB-1和ZB-6对斑蝥素和去甲斑蝥素均有增效作用,当助剂最佳加入量为8%时,同浓度ZB-1对斑蝥素和去甲斑蝥素胃毒致死中浓度的增效倍数分别为3.47和3.28倍;同浓度ZB-6对斑蝥素和去甲斑蝥素增效倍数分别为3.52和1.97倍。更多还原

【Abstract】 This paper studies on insecticidal activity and Bioassays of Cantharidin (C10H12O4) which is insects’natural products and Demethylcantharidin which is cantharidin analogues. The bioassay result showed that Cantharidin(C10H12O4) and Demethylcantharidin have obviously insecticidal function, including stomach poisoning and antifeedant activity, to the 3th instar larvae of Plutella xylostella L. The main symptoms are that activity of the tested insect decreases and the porepart of body turns black. The LD50 of Demethylcantharidin and Cantharidin is 819.5 μg/g and 8.6875 μg/g, repectively, the former is 94.4 times to the later. The AFC50 of Demethylcantharidin and Cantharidin in selective are 20.46 mg/L and 2.67 mg/L, repectively, the former is 7.66 times to the later. The AFC50 of Demethylcantharidin and Cantharidin in non-selective are 7.63 mg/L and 0.69 mg/L, repectively, the former is 11.06 times to the later. The synergists ZB-1 and ZB-6 have both positive synergism to the efficiencies of cantaridin and demethylcantharidin. By LC50 values the efficiencies of cantaridin and demethylcantaridin stomach poison to the.test insecticidal increased 3.47 and 3.28 times after it mixed with 8% of ZB-1 respectively; and increased 3.52, 1.97 times after it mixed with same density of ZB-6 respectively, Similarly.更多还原