Toxicities of Seven Types of Pesticide to the Melon Aphid Aphis gossypii

[Aims] The toxicities of seven insecticides to melon aphid Aphis gossypii were studied by leaf-dipping method.[Results] The results showed that abamectin had the highest toxicity with LC50 of 8.2728 mg/L,next was the emamectin benzoate with LC50 of 23.2278 mg/L.The LC50 of acetamiprid,imidacloprid and chlorpyrifos were 29.2927,46.0487 and 48.9797 mg/L respectively.The average mortality was 8.9 and 11.2% under the treatment of spirotetramat after 48 and 72 h.The corrected average mortality was 37.97% under the treatment of beta-cypermethrin with concentration of 2000 mg/L after 24 h.[Conclusions] The toxicity of the seven pesticides to the Aphis gossypii from high to low is abamectinemamectin benzoateacetamipridimidaclopridchlorpyrifosbeta-cypermethrinspirotetramat.