ELECTROANTENNOGRAPHIC AND COUPLED GAS-CHROMATOGRAPHIC ELECTROANTENNOGRAPHIC RESPONSES OF THE MEDITERRANEAN FRUIT-FLY, CERATITIS-CAPITATA, TO MALE-PRODUCED VOLATILES AND MANGO ODOR

We have identified five compounds from the headspace of calling male M editerranean fruit flies (medfly), Ceratitis capitata (Wiedemann), and three compounds from the headspace of ripe mango (Mangifera indica L) . using coupled gas chromatographic-electroantennographic (GC-EAG) rec ordings, coupled gas chromatographic-mass spectrometric (CC-MS) analys is, and electroantennographic (EAG) assays of standards. The male-prod uced volatiles eliciting responses from female antennae were ethyl-(E) -3-octenoate, geranyl acetate, (E,E)-alpha-farnesene, linalool, and in dole. An EAG dose-response test of linalool enantiomers and indole wit h female medfly antennae showed relatively strong EAG activities, but no significant difference between (R)-(-)-linalool and (S)-(+)-linaloo l. The three mango volatiles were identified as (1S)-(-)-beta-pinene, ethyl octanoate, and beta-caryophyllene. in addition, a strong antenna l response was recorded from a contaminant, alpha-copaene, present in a commercial sample of beta-caryophyllene. The EAG response amplitudes from both male and female antennae to the above three mango volatiles were significantly greater than to a hexanol control. For both male a nd female medfly antennae, the greatest EAG responses were elicited by beta-caryophyllene followed by ethyl octanoate. The mean EAG response s of female antennae to beta-caryophyllene and (1S)-(-)-beta-pinene we re significantly greater than those of male antennae.