Quarantine implications of exposing Epiphyas postvittana (Walker) (Lep., Tortricidae) larvae to sub‐lethal high‐temperature controlled atmosphere treatments

Abstract

Abstract: The post‐treatment development and reproductive behaviour of Epiphyas postvittana (Walker) were investigated after first, third, and fifth instars were exposed for 0, 1.5 and 4 h to a controlled atmosphere (CA) treatment (1.2% O2, 5% CO2, 40°C). Fifth instars treated for 4 h in CA had a significantly reduced survival rate to pupation, a changed sex ratio, increased pupal deformity and lower female pupal weight. This CA treatment also significantly reduced oviposition in those females which emerged as adults. Similar trends were found in fifth instars treated for 1.5 h in CA and in third instars treated for 4 h in CA. However, 1.5 h CA treatment on third and first instars did not adversely affect any of the developmental parameters that were measured. No significant changes were identified in the reproductive behaviour of moths emerging from larvae that were treated in CA as first (1.5 h) or third instars (1.5 and 4 h) compared with the untreated controls. Further, the viability of eggs oviposited by females treated with CA during their larval stages, was not affected.