四种类型杀虫剂对麦长管蚜的温度效应及其与主要解毒酶的关系

为了明确杀虫剂毒力受温度的影响及其程度,本文测定了4大类8种药剂在10～25℃下对麦长管蚜的毒力;并测定了麦长管蚜Sitobion avenae(Fabricius)在不同温度下2个解毒酶和1个靶标酶的活性差异。结果表明,高效氯氰菊酯对麦长管蚜表现不规则负温度系数,啶虫脒表现不规则正温度系数,高效氟氯氰菊酯对麦长管蚜的毒力不受温度影响,其他药剂(辛硫磷、毒死蜱、灭多威、丁硫克百威、吡虫啉)均表现为明显的正温度系数效应,以有机磷类杀虫剂表现最为明显,毒死蜱温度系数高达57.70。酶活性实验表明:麦长管蚜在高温下GST活性增强,羧酸酯酶和乙酰胆碱酯酶活性降低。它们的变化规律表明:GST活性与负温度系数密切相关,正温度系数与羧酸酯酶活性和靶标酶乙酰胆碱酯酶活性有关。

Effect of temperature on the toxicity of several insecticides to the English grain aphid,Sitobion avenae

The toxicity of eight conventional insecticides to Sitobion avenae（Fabricius） was measured at 10,15,20 and 25℃ respectively and the activity of three detoxifying enzymes and one target enzyme examined.The results show that β-cypermethrin is a negative temperature coefficient insecticide whereas acetamiprid is a positive temperature coefficient insecticide,however,the effect of temperature on the toxicity of these insecticides was irregular.The toxicity of λ-cyhalothrin was not significantly influenced by temperature and all other insecticides were positive temperature coefficient insecticides.High temperatures increase GST activity in S.avenae which enhances carboxylesterase and acetylcholinesterase lessene.The results show that the activity of GST is closely related to negative temperature insecticides,whereas the effectiveness of positive temperature insecticides is strongly linked to carboxylesterase and acetylcholinesterase activity.