DIAPAUSE IN CHRYSOPA CARNEA (NEUROPTERA: CHRYSOPIDAE): II. MAINTENANCE BY PHOTOPERIOD

Abstract

After diapause was initiated in reproductively active adults, short-day (LD 12:12) maintained diapause and prevented oviposition for 66 ± 22 days. Subsequently all females remaining in the conditions that produced diapause (LD 12:12), began to lose the red-brown diapause coloration and began to oviposit. When animals were transferred to long-day at various intervals during diapause, oviposition resumed within similar time periods, thereby indicating that the intensity of diapause did not differ at the times tested.We suggest that in nature the short days of early autumn induce diapause, that the short days of late autumn maintain this diapause, that subsequently diapause ends under short-day conditions and that factors other than photoperiod, such as temperature accumulations, play a primary role in timing the initiation of reproduction in late spring.