Oviposition-Deterring Pheromone System of Apple Maggot Flies

Contact Chemoreception

“…Females have also been observed running over the fruit surface for some time before oviposition occurs (Prokopy, 1981; see also Chapter 11). It can be assumed that this sampling of the dry surface does increase the sensory input to the CNS by the multiple contacts of the tarsal hairs during these inspection runs.…”

Host Utilization by the Walnut Fly,Rhagoletis juglandis(Diptera: Tephritidae)

“…Host marking behavior consisted of females dragging their ovipositors along the fruit surface. Such behavior has been demonstrated in numerous Rhagoletis species to be indicative of the deposition of host marking pheromone (Prokopy 1981b). The recently punctured fruit were collected, dissected, and the number of eggs within the puncture counted.…”

“…Females in the genus Rhagoletis assess and reject infested fruit on the basis of a marking pheromone that is deposited on the fruit surface after oviposition by previous females. Thus, marking pheromone in this system is believed to minimize larval competition by causing females to distribute their clutches more uniformly within host patches than is expected by chance alone (Prokopy 1981a(Prokopy , 1981bBauer 1986;Averill and Prokopy 1989).…”

“…Still, work on other tephritid ßies suggests that reuse would exact costs for larvae forced to compete with older or more numerous conspeciÞcs. Such competition has always been posed as the primary reason that many tephritid species avoid laying eggs in previously infested fruit (Prokopy et al 1978, Prokopy 1981b.…”

Chemical environment manipulation for pest insects control

“…Whereas some species achieved necessary aggregation by means of aggregation pheromones, others employ "epideietic" pheromones to prevent overcrowding (Prokopy 1981a(Prokopy , 1981b. Epideictic pheromones function by elieiting dispersal of arriving eonspecifies away from limited food resources, and may deter landing, feeding, and/or disruption.…”