Oviposition Factors of Ponticulothrips diospyrosi on Persimmon Seedling Leaves

The thrips Ponticulothrips diospyrosi Haga et Okajima is an univoltine species which aestivates and overwinters in the adult form in the fields. The oviposition factors of the thrips were investigated on persimmon seedling leaves. The adult female could make a gall and oviposit inside it in vitro. Female could make a gall and oviposit at 20℃, but only make a gall at 15℃. Although it could neither make a gall nor oviposit at 25℃, it oviposited at than temperature when placed on a gall. Female neither made a gall nor oviposited on an extended young leat. However, it could oviposit on the young leaf rolled artificially in a line tube (3.2 mm diam.), but not on the old one. These findings show that univoltine of the thrips may be regulated by the phenology of the host plant and females can oviposit whenever they are placed on the seedlings at the optimum oviposition temperature.