Impact of sex, age and mating status on flight behavior of the navel orangeworm (Amyelois transitella) (Lepidoptera: Pyralidae)

The navel orangeworm is known to have inter-orchard dispersal capacity, but knowledge of the effect of sex and mating capacity has been lacking. Laboratory studies have revealed important and practically relevant differences in dispersal between sexes or mated and unmated adults in other pest Lepidoptera. In the current laboratory study, the flight mill performance of mated navel orangeworm adults is compared with previous data for unmated adults.  The distance and duration of the longest uninterrupted flight, and of the sum of all flights, was compared between classes of age (2, 3, 5 or 7 day-old adults), sex, and mating status (unmated vs. mated). Flight performance was significantly affected by age and sex for all parameters examined. Mated adults flew less time than their unmated counterparts. There was a trend of stronger flight performance in unmated than in mated males, although interaction of sex and mating status was not significant for any of the parameters examined. These findings suggest greater dispersal capacity for mated females than males. The implication of this finding for pheromone-based monitoring for navel orangeworm is discussed.