Chemical Composition of Essential Oil From Tetradenia riparia and Its Attractant Activity for Mediterranean Fruit Fly, Ceratitis capitata

The Mediterranean fruit fly or medfly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), is one of the most economically important invasive pests worldwide, with over 300 known hosts. Essential oils have great promise for application in integrated pest management, where they function as natural repellents, attractants, and toxicants with a reduced impact on the environment. In this study, we evaluated essential oil from aerial parts of the African ginger bush, Tetradenia riparia (Hochst.) Codd (Lamiaceae), as a potential new attractant for male C. capitata. Tetradenia riparia essential oil (TREO) was analyzed by gas chromatography (GC)-flame ionization detection and GC-mass spectrometry (GC-MS). The primary compounds identified were fenchone (15%), delta-cadinene (11%), 14-hydroxy-beta-caryophyllene (8%), and tau-cadinol (7%). In short-range laboratory bioassays with sterile male medflies, TREO exhibited attractancy comparable to that observed with a positive control, essential oil from tea tree (Melaleuca alternifolia (Maiden and Betche) Cheel.). This study provides the first report of C. capitata behavioral response to TREO. Further research is needed, particularly with the 2 enantiomers of fenchone, to determine the chemical constituents responsible for the attraction of C. capitata.