Action Range of the Sex Pheromone of the Rice Stem Borer Moth, Chilo suppressalis (WALKER) (Lepidoptera: Pyralidae)

To obtain the basic information for establishing the pheromonal monitoring system in C. suppressalis, the range of the synthetic sex pheromone were estimated. In a playground the range of stimulation was estimated by observing behavioural responses of caged male moths to be 36.8 m at a wind speed of 0.36 m/s with little difference between the generations. The daily sampling range in the paddy field was estimated by trap interaction experiments to be more than 100 m in radius for the overwintered generation and ca. 50 m in radius for the first one. Also, the mean flight distance of marked male moths during one night was significantly longer in the overwintered generation (112.0 m) than in the first (18.8 m).