Impact of Flight Behavior on Reproductive Success in the Navel Orangeworm (Amyelois transitella)

Monday, February 22, 2016 - 4:10pm
Event Type: 

Angela Rovnyak, Iowa State University, Department of Entomology

Monday, 4:10pm E164 Lagomarcino Hall

M.Sc. defense seminar

Abstract. The Navel Orangeworm Amyelois transitella (Lepidoptera: Pyralidae) is a major crop pest of almonds and pistachios in California. Effective management requires an understanding of its capacity for spreading between orchards and what trade-offs, if any, exist between flight and reproductive capacity. Two experiments were conducted to investigate the relationship between flight and reproduction in this species. For both experiments, female moths were weighed on the day of eclosion and assigned to a control or experimental group. For the first experiment, tmoths were allowed a full night to fly on flight mills. Following successful flight and mating, fecundity was monitored by counting total and fertile eggs laid daily until death. Handling the moths reduced fecundity, however flight distance, duration and timing relative to mating did not affect fecundity. Moths that mated prior to flying flew longer and farther than those that mated after flight. In the second experiment, females were forced to fly for discrete periods of time (3, 30, 60 or 120 minutes) during the day. Flight duration did not affect the total number of eggs or number of fertile eggs laid. While the amount of weight lost increased with flight duration, this did not affect fecundity or longevity. There was no difference in fecundity between the moths that took voluntary flights and those that were forced to fly. Together these results are consistent with the navel orangeworm being a long-distance disperser, primarily after mating in the natal orchard. Implications for management and colonization of uninfested orchards will be discussed.