DIAPAUSE DEVELOPMENT IN THE CHESTNUT WEEVIL CURCULIO-ELEPHAS

Larval diapause development in the chestnut weevil Curculio elephas (C oleoptera, Curculionidae) was studied in the laboratory at different t emperatures. The results proved that exposure to low temperatures (3-6 -degrees-C) in the period December-February is not required to complet e diapause. The diapause is terminated in December and from January on , the larvae can initiate post-diapause morphogenesis in the laborator y, if temperatures allow it. In the field developmental rates are negl igible during winter cold (4-6-degrees-C) and only after March morphog enesis can proceed with no interruption until adult emergence. Diapaus e and post-diapause quiescence contribute to individual synchronizatio n for initiation of development. The observed spread of adult emergenc e was 30 days in the laboratory. This variability produced during post -diapause development may be a response to annual variation in the phe nology of the chestnuts.