Wintering and spring emergence of codling moth, Cydia pomonella (L) (Lepidoptera: Tortricidae) in south eastern Australia.

Abstract

Codling moth winters as dormant fifth instar larvae which complete their development in spring. In south-eastern Australia, three temperature regimes contribute to determine the emergence times of spring adults, i.e. a conditioning regime in autumn, a chilling regime in winter, and a dormancy-ending regime in spring. The influences of each regime are examined and discussed. Short winters and early springs tend to increase the variability of emergence dates. This is thought to represent an important adaptive response of the species to climatic variations. Comprehensive predictive models of spring brood events cannot be made at present for lack of sufficient knowledge of the various processes involved.