PHOTOPERIODIC DETERMINATION OF INSECT DEVELOPMENT AND DIAPAUSE .5. DIAPAUSE, CIRCADIAN-RHYTHMS, AND PHASE RESPONSE CURVES, ACCORDING TO DUAL SYSTEM THEORY

The dual system theory of photoperiodic time measurement provides a satisfactory basis for the interpretation of photoperiodic determination of diapause, effects of different photoperiodic regimes on circadian rhythms of adult eclosion, and the phase response curve. A fundamental unity of photoperiodic time measurement in a wide variety of organisms is strongly suggested by the dual system theory. [Insects mentioned include Ostrinia nubilalis, Pieris brassicae, Drosophila and Pectinophora gossypiella.].