Sex pheromone communication from a population resistant to mating disruptant of the smaller tea tortrix, Adoxophyes honmai Yasuda (Lepidoptera: Tortricidae)

Abstract

In Adoxophyes honmai, a population that has developed resistance to a disruptant composed of (Z)-11-tetradecenyl acetate was recognized in Shimada in Shizuoka Prefecture. The sex pheromone components of the resistant population were individually analyzed. The average amounts of (Z)-9- and (Z)-11-tetradecenyl acetates were 40.5 ng and 45.6 ng, respectively, whereas the averages in the susceptible population were 39.9 ng and 15.1 ng. The results suggest that resistant females biosynthesize more (Z)-11-tetradecenyl acetate in order to heighten the ratio of the acetate in the sex pheromone component. A 40 : 60 blend of (Z)-9- and (Z)-11-tetradecenyl acetates was the best of six kinds of lures tested on resistant males. The male response tunes to the sex pheromone blend produced by resistant females. Although no attractiveness has been generally observed in a lure impregnated with only (Z)-9-tetradecenyl acetate, males were attracted to the incomplete lure treated with the mating disruptant in the field. Resistant males supposedly utilize the widespread odor of (Z)-11-tetradecenyl acetate released from mating disruption devices installed in the tea canopy for orientation, while they trace a directional plume of (Z)-9-tetradecenyl acetate emitted from the lure.