First data on the repellent activity of essential oils of Citrus limon towards medfly

The biological activity of peel essential oils of two Sicilian cultivars of C. limon, 'Interdonato ' and 'Lunario', was investigated by electrophysiological recordings (EAG) and field trials on Ceratitis capitata (Wiedemann) (Diptera Tephritidae). The EAG data showed a remarkable dose-response relationship and a low activation threshold dose (10-3M) for both essential oil extracts. In field tests, essential oils showed a good repellent and antiovipositional activity on 'Navelina' oranges, and in particular the essential oils of 'Lunario 'provided the same results of kaolin. Potential applications of essential oils from C. limon cultivars against C. capitata in organic farming are discussed. Keywords: Mediterranean fruit fly, lemon peel, antiovipositional activity, EAG, orange orchards, Navelina, field trials.