Selection of Insecticides for Controlling Chestnut Curculio (Curculio sikkimensis)

Susceptibility of Curculio sikkimensis adults to 39 commercial insecticides were evaluated by body dipping method, Among them sixteen insecticides of chlorpyrifos, fenitrothion, fiponil, phenthoate, benfuracarb, thiodicaib, carbosulfan, bifenthrin, cypermethrin, -cyhalothrin, deltamethrin, clothianidin, acetamiprid+diflubenzuron, etofenpox+diazinon, esfenvalerate+fenitrothion and furathiocarb +diflubenzuron showed 100% mortality. Insecticides with over 80% residual effect at 1 day after treatment were phenthoate, benfuracarb and thiodicarb (95.0, 82.5, and 85.0%, respectively). However, after that, it was dropped rapidly. Other insecticides showed low residual effect. In the control efficacy test on C. sikkimensis, insecticides with over 90% control values at 1 day after treatment were phenthoate, thiodicarb, fipronil, acetamiprid+bifenthrin and furathiocarb+diflubenzuron. However, all insecticides from 2 days after treatment were over 90%.