Abstract
Mating suppression of Spodoptera litura (F.) by a pheromone component, (Z, E)-9, 12-tetradecadienyl acetate (litlure B), was evaluated in the field. Litlure B (4 mg) evaporating from four absorbent cotton balls brought about 89.8% suppression of mating of 36 tethered females in a 12.5-m2 area. The suppression persisted for 30 days when a rubber septum (40-mg litlure B per septum) was used as an evaporation substrate. Seasonal fluctuation of the mating suppression suggested the importance of population density of this insect to the degree of suppression. Location of the evaporation points of litlure B greatly affected the mating suppression. Satisfactory results were obtained when the evaporation points were evenly distributed in the area at the same height at females. More than 90% suppression of mating was observed when 50μg of litlure B was applied directly to the wings of each tethered female.
