抄録
Calling activity in Cnaphalocrocis medinalis showed a distinct diel periodicity. Moths showed high activity during 5–7 h into the scotophase. To clarify the temporal change of pheromone titers in the pheromone gland within 1 d, age 4 females were used. The changes in the calling activity and titer of the four sex pheromone components, (Z)-11-octadecenal (Z11-18:Ald), (Z)-13-octadecenal (Z13-18:Ald), (Z)-11-octadecen-1-ol (Z11-18:OH) and (Z)-13-octadecen-1-ol (Z13-18:OH), in the pheromone glands were roughly synchronous. At age 4, however, the pheromone components could already be detected at the onset of scotophase, while calling began at 3 h into the scotophase. Furthermore, calling was most active between age 3 and age 7, whereas the highest level of pheromone titer at 6 h after light off was observed from age 3 to age 5. These findings suggest the presence of different controlling mechanisms between calling behavior and pheromone production. The ratio of the four sex pheromone components remained relatively constant at all times of the day and all ages.
