SENSITIVITY OF TUFTED APPLE BUDMOTH (LEPIDOPTERA: TORTRICIDAE) LARVAL INSTARS TO PHOTOPERIODIC INDUCTION OF DIAPAUSE AT 21C

An examination of the sensitivity of the tufted apple budmoth, Platynota idaeusalis (Walker), larval instars to a diapause-inducing photoperiod at a constant 21C revealed that maximum expression of diapause occurred only when all five instars were exposed to a short daylength. No intermediate instar was found in which the developmental program could be switched from a diapause to a non-diapause one, or vice versa.