Lifetime Fecundity and Body Size of Monochamus alternatus (Coleoptera : Cerambycidae) at a Constant Temperature

To elucidate the relationship of maternal size to ovipositional traits in Monochamus alternatus, 13 differently-sized adult females were reared under laboratory conditions. There was a large variation in lifetime fecundity ranging from 0 to 343 eggs with an average of 105.0. The lifetime fecundity was correlated positively with rate and period of oviposition, between which there was no significant correlation. The rate and period of oviposition were correlated positively with the female body size and longevity, respectively. The variations in oviposition rate and period accounted for 38.2% and 44.0% of the variance of lifetime fecundity, respectively. Path analysis showed that an increased female body size contributed an increase in lifetime fecundity through the oviposition rate 24 times more greatly than that through the oviposition period. The ovariole number varied from 20 to 25 with a mean of 22.5 among 48 females examined. Since the ovariole number was almost unchanged with respect to the maternal size, the individual variation in ovipositon rate was not explained by the ovariole number.