Control of the beet armyworm, spodoptera exigua (hüebner) (lepidoptera: Noctuidae), using synthetic sex pheromone. II. Effect of communication disruption in the greenhouse and combination effect with light-trap

Abstract

Synthetic sex pheromone was evaporated from sealed polyethylene tubes containing a 7:3 mixture of (Z, E)-9, 12-tetradecadienyl acetate and (Z)-9-tetradecen-1-ol at the rate of 500 dispensers/10a into a Welsh onion greenhouse. In the treated greenhouse, the larval density of Spodoptera exigua was drastically reduced within 1 month, while the density increased to ca. 9 times of initial density in the untreated one. Treatment with 500 dispensers in a 2a greenhouse was estimated to reduce the mating rate of females to 20-50%, whereas it was 95% or more with no treatment. Capture of males with a light trap (lamp: BLB 30W) was considered to reduce the female mating rate to ca. 30%. When sex pheromone treatment was combined with a light trap, mating rate was decreased to 2-3%. This combination would be effective in the control of S. exigua in a small greenhouse. © 1990, JAPANESE SOCIETY OF APPLIED ENTOMOLOGY AND ZOOLOGY. All rights reserved.