Identification, synthesis, and field evaluation of the sex pheromone of the citrus fruit borer Ecdytolopha aurantiana

The sex pheromone of the citrus fruit borer Ecdytolopha aurantiana has been identified by gas chromatography coupled to an electroantennographic detec tor (GC-EAD). The electron impact mass spectral (EI-MS) fragmentation of th e major EAD-active peak gave identifying features for a monounsaturated ace tate. Further analyses by chemical ionization mass spectrometry (CI-MS), va por-phase infrared spectroscopy (GC-IR), along with chemical derivatization (DMDS reaction), led to full characterization of the major component as (E )-8-dodecenyl acetate (E8-12: Ac). The second constituent was identified as the related alcohol, (E)-8-dodecenol (E8-12: OH). The;two compounds were i ndistinguishable from the authentic synthetic standards in chemical and EAD analyses. Samples of the two compounds were obtained by a facile synthesis utilizing lithium chemistry. Field tests showed that captures in traps bai ted with a mixture of E8-12: Ac and E8-12: OH at 100: 1 and 10: 1 ratios we re not significantly different from the catches in traps having two virgin females, Dosage tests showed better performance of traps baited with I mg t han those with 0.1 mg of the pheromone blend, either in 100: 1 or 10: 1 rat io.