Exposure to Grapefruits and Grapefruit Oil Increases Male Mating Success in the Mediterranean Fruit Fly (Diptera: Tephritidae)

Abstract

Exposure to certain plants or plant compounds may influence the mating success of male fruit flies (Diptera: Tephritidae). Earlier research demonstrated that males of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann), exposed to ginger root oil (Zingiber officiale Roscoe), bark of the common guava (Psidium guajava L.), oranges (Citrus sinensis Osbeck) or orange oil obtain significantly more matings than non-exposed (control) males. The purpose of the present study was to determine whether male exposure to another Citrus species, the grapefruit C. paradisi Macfad., also resulted in increased mating competitiveness of male medflies. Consistent with the data from oranges, males exposed to grapefruits or grapefruit oil had a mating advantage over non-exposed (control) males. In addition, as reported for orange oil, males exposed to grapefruit oil displayed an elevated level of sexual signaling (pheromone-calling), which presumably contributed to their increased mating frequency. The finding that grapefruit, a second Citrus species, produced similar effects as oranges suggests that citrus fruits, in general, may enhance the mating performance of male medflies.