IDENTIFICATION OF SEX-PHEROMONE COMPONENTS OF THE SIBLING SPECIES EUXOA RIDINGSIANA (GRT.) AND EUXOA MAIMES (SM.) (LEPIDOPTERA: NOCTUIDAE), AND BLENDS FOR THEIR SPECIFIC ATTRACTION

Abstract

AbstractThe sex-pheromone components of the sibling species Euxoa ridingsiana and Euxoa maimes were identified in abdomen-tip washes and extracts of calling female moths. Both species produced the same primary pheromone component, (Z)-9-tetradecenyl acetate (i.e. Z9-14:Ac), but they produced different amounts of secondary pheromone components. In the field, male moths of E. ridingsiana were specifically attracted to a 3-component blend of Z7-12:Ac, and Z7-14:Ac, and Z9-14:Ac in a ratio of 1:2:40 at 500 μg per dispenser, and males of E. maimes were specifically attracted to a 5-component blend of Z7-14:Ac, Z9-14:Ac, Zl 1-14:Ac, Zll-16:Ac, andZll-16:OH in a ratio of 1.5:500:5:50:2.5 at 500 μg per dispenser. Both synthetic pheromone blends were competitive with conspecific females. These pheromone analyses confirm that E. ridingsiana and E. maimes are valid biological species that can maintain their reproductive isolation solely by specific sex pheromones.