抄録
The effects of moth age on the mating behavior of the rice stem borer moth, Chilo suppressalis WALKER, were investigated. The mating frequency of same-aged pairs was low at 1 day old, reached the maximum at 2 or 3 days old, and, thereafter, decreased rapidly with age. The pattern of effects of age on mating activity was different between male and female. The female activity maintained a high level up to an age of 4 days, but thereafter, it decreased rapidly. The male activity was at a low level in newly emerged moths, attained a peak at 3 or 4 days old, and was kept rather high level until 8 or more days of age. It seems that in same-aged pairs, the low level of mating success at 1 day old was due to male activity and the rapid reduction of it after 4 days was determined by the females. The begining of mating and calling became earlier with age. These results should be considered whne the sex pheromone is applied in the field to control this insect.
