Mating disruption to control Amyelois transitella (Lepidoptera: Pyralidae) in California fig orchards

Mating disruption is a pest management strategy that utilizes high concentrations of synthetic pheromone to impede the ability of males and females to successfully locate each other and mate. Previous studies have demonstrated that this technique can be successfully used to reduce populations and crop damage from moth pests in both annual and perennial cropping systems. Here, we investigated the effects of a novel mating disruption product on navel orangeworm, Amyelois transitella (Walker), in California fig orchards. In this two-year study, A. transitella populations and crop damage were monitored at five sites each with paired 30-acre plots with and without mating disruption. Within each plot, female and male A. transitella populations were monitored with baited wing traps that were checked weekly. A pheromone lure was used to attract males while a bait bag with almond and pistachio meal was used to attract gravid females into traps. Commercial fig orchards are harvested multiple times per year, and thus crop damage was evaluated with each successive harvest event, for a total of 5-6 damage evaluations per year. Results indicate that while mating disruption reduced male moth catch in traps baited with pheromone lure, female moth catch in traps with bait bags was unaffected. Crop damage was also unaffected by mating disruption, but site and harvest date affected infest levels. We provide preliminary data on moth fatty acid profiles to discuss the potential of spill over effects from tree crops into fig orchards.