Mating disruption of Pandemis spp. (Lepidoptera : Tortricidae)

We evaluated the potential of sex pheromones to disrupt moth communication and mating of Pandemis leafrollers (likely P. pyrusaa Kearfott). The sex ph eromone of P. pyrusana, 94:6 (Z)-11-tetradecenyl acetate (Z11-14:Ac): (Z)-9 -tetradecenyl acetate, was compared with Z11-14:Ac alone, (E)-11-tetradecen yl acetate (E11-14:Ac) alone, and a 94:6 blend of Z11-14:Ac and (Z)-11-tetr adecanal in replicated trials in 0.1-ha plots. All blends significantly red uced moth captures in lure-baited traps and mating of tethered, virgin fema les. No significant differences were found among pheromone blends, except t rap catches in plots treated with E11-14:Ac were significantly higher than in the other pheromone-treated plots. No significant differences in moth ca tch were found in plots treated with 250-1,000 dispensers per hectare relea sing the Pandemis pheromone blend. The percentage of disruption in treated versus untreated plots was not related to the mean dispenser emission rate measured over 2-wk time periods for dispensers releasing either the Pandemi s pheromone or Z11-14:Ac alone. However, percentage disruption in plots tre ated with pheromone was significantly and negatively related to population density measured as moth catch in the untreated plots, Larger orchard trial s are needed to evaluate the efficacy and economics of using 500-700 dispen sers per hectare loaded with Z11-14:Ac to manage Pandemis.