First data on the repellent activity of essential oils of Citrus limon towards medfly (Ceratitis capitata)

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 activi- ty on ‘Navelina’ oranges, and in particular the essential oils of ‘Lunario’ pro- vided the same results of kaolin. Potential applications of essential oils from C. limon cultivars against C. capitata in organic farming are discussed.