PHOTOPERIODIC EFFECT ON DIAPAUSE INDUCTION AND DEVELOPMENT IN THE PREDATOR ORIUS-INSIDIOSUS (HETEROPTERA, ANTHOCORIDAE)

Photoperiod influenced nymphal development and diapause induction in a laboratory culture of Orius insidiosus (Say). At 20-degrees-C, development of nymphs was significantly faster at a photoperiod of 10:14 (L:D) than at 12:12, 13:11, 14:10, or 15:9. Subsequently, diapause induction exhibited a typical long-day response; nearly 100% of adult females entered reproductive diapause when reared under short photoperiods (10:14[L:D]), whereas at longer photoperiods (12:12, 13:11, 14:10, 15:9[L:D]), fewer insects initiated diapause (56.8, 29.7, 5.3, 12.9%, respectively). The critical photoperiod fell between 12:12 and 13:11 (L:D). Duration of the preoviposition period was inversely related to photoperiod.