Effect of photoperiod on the induction and maintenance of diapause and on development of the predatory bugPodisus maculiventris (Hem.: Pentatomidae)

The predatory bugPodisus maculiventris Say displays a reproductive diapause. In the laboratory, at 23±1°C, when the pre-imaginal stages were reared on larvae ofGalleria melonella L. (Lepidoptera: Pyralidae) under a short photoperiod of 8L: 16D, diapause was induced in all adult females, whereas under a long photoperiod of 16L: 8D none entered diapause. Nymphal development was faster under the diapause-inducing short photoperiod than under the diapause-averting long photo-period. By contrast, embryonic development was faster under the long than under the short photoperiod. Diapause maintenance was also under the control of photoperiod. After a 10-d-period of chilling at 4°C, diapause was quickly terminated in adults kept under long photoperiod whereas it was maintained in most of those kept under short photoperiod. The predation rate of non-diapause or post-diapause adult females was much higher than that of diapause females.