几种常用杀虫剂对瓜蚜的毒力和对乙酰胆碱酯酶的抑制作用

用叶片药膜法测定了4种常用杀虫剂氧乐果、辛硫磷、三唑磷、吡虫啉对呼和浩特市郊蔬菜基地温室黄瓜上发生的瓜蚜的毒力。结果表明，瓜蚜对吡虫啉最敏感，LC50 仅为4.203 mg/L，氧乐果、辛硫磷、三唑磷对瓜蚜的LC50分别为21.70、38.86、43.30 mg/L。研究明确了3种有机磷杀虫剂对瓜蚜体内乙酰胆碱酯酶AChE均有明显的抑制作用，并随着抑制时间的延长，抑制率增加。I50值分别为氧乐果9.6×10-6mol/L，辛硫磷11.4×10-6mol/L，三唑磷17.1×10-6mol/L。

Toxicities of several insecticides and inhibition of acetylcholinesterase in Aphis gossypii

The toxicities of 4 common insecticides to Aphis gossypii Glover on cucumber plants were studied in the greenhouses using leave dipping method. The results showed that A. gossypii was most sensitive to imidacloprid in the insecticides tested, and LC50 was 4.203 mg/L. The LC50 values for omethoate, phoxim and triazophos were 21.70, 38.86 and 43.30 mg/L, respectively. It was shown that 3 OP insecticides tested could significantly inhibit the activity of AChE in A. gossypii, and their inhibition activities increased over time. The I50 values of omethoate, phoxim and triazophos to AChE were 9.6×10-6, 11.4×10-6 and 17.1×10-6mol/L, respectively.