Performance of Sterile CACTOBLASTIS CACTORUM (Lepidoptera: Pyralidae) Females in Luring Males to Traps

Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae) is renown for its control of invasive cacti (Opuntia spp.). Its accidental arrival in Florida and its rapidly expanding range along the Gulf coast pose an imminent threat to native Opuntia spp., especially in the southwestern U.S. and Mexico. Adequate survey techniques are crucial in order to delineate the rate of spread of this invasive species. Virgin female-baited sticky traps have been effective in detecting C. cactorum adult males in areas where visual surveys failed to detect larval damage. However, the use of fertile females in traps placed beyond the currently infested area is discouraged because an escaped fertile female might establish a breeding population and expand the infested area. In this study we compare the attractiveness and the longevity of fertile and irradiated (sterile) females deployed as bait in traps. Traps baited with females sterilized with gamma radiation were as effective as traps baited with unirradiated (fertile) females in detecting populations of feral C. cactorum male moths.