Epsilon Open Archive

Abstract

Fruit fly is a common name given for two distantly related families: Tephritidae and Drosophilidae. Flies in the family Tephritidae, unlike most of Drosophilidae are referred to as true fruit flies, as they damage fruits before they are overripe or rotten. There are about 500 genera in this family, of which several are serious pests of commercially grown fruits and vegetables. Flies in the subfamily Dacinae are of considerable agricultural concern in the tropics and sub-tropics causing direct damage through infestation and indirect damages via quarantine restrictions. Control strategies include trapping with protein baits and male annihilation, both of which are based on olfactory behaviour of the flies. Protein baits and host volatiles attract both sexes, but are less effective compared to parapheromones that attract only males of Dacinae. Parapheromones not only attract, but also strongly induce phagostimulation. Males that fed on parapheromone appear to gain selective advantage. Alternatively, but not mutually exclusive, parapheromones may act as rendezvous site marking. Apart from its function, the mechanism by which males recognize parapheromone is not understood. In order to clarify this, it is crucial to look further into the peripheral olfactory system and find the sensory neurons that are responsible for detecting parapheromones. Structure-activity studies and comparative studies on homologous sensory circuits in females and in closely and distantly related species of tephritid flies might elucidate the evolutionary origin of parapheromones and identify new avenues for use in the control of these global pests.