Isolation and identification of male medfly attractive components inLitchi chinensis stems andFicus spp. stem exudates

Short-range attraction/feeding stimulation of male Mediterranean fruit flies Ceratitis capitata (Wiedemann), (Diptera: Tephritidae)] to a stem extract of a host plant,Litchi chinensis Sonn. (Sapindaceae), and to milky exudates from stems of nonhost plants,Ficus retusa L. andF. benjamina L. (Moraceae), were attributed to the presence of the sesquiterpene -copaene. The presence of -copaene in the milky exudate from stems ofF. benghalensis L. is also suggested as eliciting similar behavioral responses in male medflies. The presence of minor quantities of -ylangene in the plants and its contributory effects to the behavioral response of male medflies is discussed. Short-range attraction/feeding stimulation of male medflies to equal amounts of -ylangene-free -copaene samples (94.5%+), prepared from -copaene-enriched angelica seed oil and copaiba oil, respectively, showed no difference in intensity of response. -Ylangene elicited a slightly less intense response for male medflies than -copaene.Names of products in this paper are included for the benefit of the reader and do not imply endorsement or preferential treatment by USDA.