Abstract
An artificial hatching methods for the wild silkmoth, Antheraea yamamai, has been developed by using imidazole derivatives. In this study appropriate techniques which are necessary for the induction of a higher ratio of diapause breakdown and hatching are described. The optimum concentration of KK-42 and KK-80, two representatives of imidazole derivatives, was 20μg/egg. The eggs used for diapause breakdown and hatching were 10-day old after oviposition and required a short period of chilling. The application of imidazole derivatives after egg chilling also induced a higher ratio compared with the application of the treatment before egg chilling. The results showed that the artificial hatching method with imidazole derivatives was effective. On the other hand, the injection of 20-hydroxyecdysone to diapausing pharate first-instar larvae which had previously received KK-42, promoted the diapause breakdown. Thus we confirmed that imidazole derivatives do not function as anti-ecdysteroid in the case of diapause breakdown in the wild silkmoth eggs.
