Chemical composition of essential oils of Pulicaria species growing in Saudi Arabia and activity for Mediterranean fruit fly, ceratitis capitata

The Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) is one of the most destructive agricultural pests in the world. New attractants are needed as a key strategy for detecting and suppressing insect pest densities. The aim of this study was to evaluate the attractiveness of essential oils isolated from the aerial parts of three Pulicaria species collected from the Al-kharj province of Saudi Arabia, targeting sterile medfly males. The volatile constituents of the aerial parts of P. arabica, P. crispa, and P. somalensis were characterized using gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. tau-Cadinol was found to be the major compound in the essential oils of P. arabica (38.6 %) and P. crispa (53.5 %), and intermedeol (15.9 %), α-cadinol (9.7 %), α-, β- (5.2 % each), and γ-eudesmol (9.1 %) were the most abundant components in the essential oil of P. somalensis. Carvotanacetone (10.3 %) was detected only in P. arabica. The essential oils from each of the three Pulicaria species were subjected to short-range attraction bioassays against the sterile male medfly C. capitata. The results were compared with the response to a known strong attractant, tea tree oil (Melaleuca alternifolia); P. arabica exhibited mild attractancy, whereas neither P. crispa nor P. somalensis showed attractant activity.