The main component for insect body wall is the chitin.This chitin is able to maintain the water balance in insect body , able to give solidarity for its body and able to give a certain shape for the insect body .Some insect growth regulators are able to prevent the formation of chitin by inhibiting the chitin synthetase. This.. lead to death of the insect after three to four days.Diflubenzorun are compounds able to do such function. Salam and best wishes .