Abstract
The effectiveness of various control methods of Thrips palmi on eggplant and sweet pepper in a plastic greenhouse was evaluated using a population model in order to develop an effective control system. The required frequency of insecticide application decreased with depression of the control threshold (CT) because of a low density effect. Since the required frequency of periodical application on eggplant starting at very low density was almost the same as that using CT, periodical application was a practical population control method.On sweet pepper, insecticide spraying alone was insufficient. Prevention of invasion, reduction of density on seedlings and mass trapping using sticky traps were effective controls against T. palmi, especially on sweet pepper. It was important to maintain low density using these methods against the population on eggplant and sweet pepper.
