The Research On Overwintering Ecology And Mating Strategy In Stenocatantops Splendens

This paper studied the ecological characteristics of the overwintering adult,the effects of temperature and photoperiod on the termination of diapause and the mating tactics of adult in Stenocatantops splendens which were collected from Changsha suburb of Hunan Province.The results were as follows:The short photoperiod could induce and maintain adult diapause. Long photoperiod could eliminate adult diapause. But the diapause could only be eliminated partly after exposed at long photoperiod for 30 days and the diapause could resume after transferring from long photoperiod to short photoperiod. However it could be weakened significantly after exposed at long photoperiod for 60 days.The adult diapause of S. splendens could be affected by not only the temperature but also the photoperiod in nature. The temperature play a important role in the elimination of adult diapause. However it was not significant that the intensity of diapause is weakened after chilling at 10℃for 30 days. It could infer that it needed more time to terminate the diapause.The high temperature could terminate the diapause as the low temperature could do. The pre-oviposition period of overwintering S. splendens were only about 34 days after transferred to 30℃from outside on December, and it had no relations with photoperiod. On the other hand, with delay of transferred to 30℃,the pre-oviposition period became more and more shorter. It could be conclude that the diapause of S. splendens was terminated by high temperature.It could be seen that female of S. splendens mate with male when the adults were collected or raised outdoors on September and October. During the dissection of the female before winter, the sperms were found in every ovary of female after November. That was to say S. splendens had finished mating before winter. But the ovary didn't develop during the winter and it didn't develop until next spring when temperature was high.The mortality of S. splendens was significantly different between male and female during winter. The percentage of male mortality was significantly higher than the percentage of female mortality. On the other hand, the supercooling point of female was significantly lower than that of male. So it could conclude that the cold tolerance was different between female and male. The female of S. splendens could safely survive severe winter for the cold tolerance of female was better than male's.