Aspects of the Biology of the Eucalypt-Defoliating Chrysomelid Beetle Paropsis Atomaria Ol. In the Australian Capital Territory.

Abstract

Young growth of Eucalyptus blakelyi with a mean twig diameter of 1.35 mm is the preferred site for oviposition by Paropsis atomaria. The number of eggs per collar is negatively correlated with twig diameter. In the laboratory, eggs kept at temperatures between 3 and 7ºC and 65-70% RH showed a severe drop in viability. Diapause of adults can be prevented, and rearing continued throughout the year, by illumination for 16 h a day and a minimum temperature of 22ºC. Observed parasites and predators of eggs and larvae, at average levels recorded over the season, may achieve 65% mortality of the population of P. atomaria, rising to 90% at the highest levels observed.