抄録
In the rice stem borer, Chilo suppressalis WALKER, the influence of material age on several biological characteristics of the offspring was investigated. The size of egg masses was the largest on the first day of oviposition, whereupon it decreased with increasing maternal age. The duration of the egg period was not affected by maternal age. Concerning the fertility and hatchability of eggs, a decreasing tendency with progress of maternal age was observed. The survival rate of newly hatched larvae decreased with an increase in maternal age. These results suggest that the eggs deposited in the late period due to their low viability contribute least to the population of the next generation as compared with earlier deposited ones.
