SPRING MIGRATION, REPRODUCTIVE-BEHAVIOR, MONITORING PROCEDURES, AND HOST PREFERENCE OF PLUM CURCULIO (COLEOPTERA, CURCULIONIDAE) ON PRUNUS SPECIES IN CENTRAL GEORGIA

Plum curculio, Conotrachelus nenuphar (Herbst), enroute from hibernating sites in the woods were first recovered from plum trees at 95% full bloom. First mating occurred as early as 95% full bloom and no later than 90% petal fall. Most matings occurred during April when the adult population was highest. Fruit injury (feeding and oviposition) was greater on plum than on peach or other Prunus species. Little feeding and/or oviposition was recorded on fruit of Prunus japonica Thunb. in field nursery plots. However, when P. japonica fruit was picked, brought into the laboratory, put in cups with laboratory-reared plum curculio, the weevils fed and oviposited as well as on other Prunus species fruit. First field brood emergence was detected when most collected adult females (16 of 18) were virgin during 26 May - 1 June 1991. The 7-day period was indicative of a new generation because newly-emerged females were sexually immature for approximately 7 days. Prior to and after that 7-day emergence period, most females were mated. Various monitoring methods were evaluated which included green sticky balls, pitfall traps, sticky trunk bands, boil weevil traps, and tree jarring. Tree jarring was the best method for monitoring plum curculio.