三种农药对红裸须摇蚊毒力和羧酸酯酶活性的影响

摇蚊是一种世界性分布的水生昆虫,常作为监测水环境污染指示生物。以红裸须摇蚊为对象,测定了氧化乐果、毒死蜱和三氟氯氰菊酯对红裸须摇蚊4龄幼虫毒力和体内羧酸酯酶活性的影响。结果表明,氧化乐果、毒死蜱和三氟氯氰菊酯12 h 致死中浓度LC₅₀分别为12.508、2.478和0.046 μg/L。低浓度(0.05 μg/L)氧化乐果处理3 h和12 h以及各浓度(除8 μg/L)氧化乐果处理48 h,摇蚊体内羧酸酯酶活性均高于对照,表现为诱导作用,其余各浓度各处理时间均表现为抑制减少。除0.125 μg/L和0.25 μg/L毒死蜱处理12 h对羧酸酯酶有诱导作用外,毒死蜱均抑制羧酸酯酶活性;而三氟氯氰菊酯也均抑制羧酸酯酶活性。因此,摇蚊羧酸酯酶可作为一种监测农药污染的生物化学标志物加以利用。

Toxicity of three pesticides and their effects on carboxylesterase activity of Propsilocerus akamusi

Chironomids are a globally-distributed family of insects that can serve as biological indicators of environmental pollution.Pollution due to pesticide usage is of particular importance due to the heavy application of these chemicals.Three routinely-applied insecticides,omethoate,chlorpyrifos,and cyhalothrin,were selected for our study to investigate their toxicity against Propsilocerus akamusi and to determine their effects on carboxylesterase activity of 4th-instar larvae.After 12 h of exposure,the LC50 va...