Effects of pheromone loading, dispenser age, and trap height on pheromone trap catches of the oriental fruit moth in apple orchards

Abstract

The effects of field aging (0–28 days) and pheromone loading rate on the longevity of red rubber septa loaded with the sex pheromone blend of the oriental fruit mothGrapholita molesta (Busck), were evaluated in North Carolina apple orchards in 2002. Separate field tests examined the influence of trap height and pheromone loading rate of rubber septa on trap catches of adultG. molesta males in an abandoned orchard. The loss of the major pheromone component, (Z)-8-dodecenyl acetate (Z8–12:OAc), from red rubber septa over a 4-week period exhibited a relatively constant release rate with 30, 100 and 300 µg pheromone. Trap catch was significantly higher in pheromone traps placed in the upper canopy than in those in the lower canopy. Pheromone traps baited with 100µg lures caught more moths compared with those loaded with 300 µg. There was no apparent relationship between pheromone trap catch and septa age, with trap catch appearing to be primarily a function ofG. molesta population density.