Effects of Temperature and Controlled Atmospheres on Codling Moth Metabolism

Abstract

Abstract Although controlled atmosphere temperature treatments are effective in controlling codling moth, Cydia pomonella (L.), in fruit, the mechanism by which this combination treatment kills the larvae is unknown. Differential scanning calorimetry was used to determine the effects of elevated temperatures, low O2, and high CO2 on the metabolic heat rate of fifth-instar codling moths. Total ATP levels also were determined. Metabolic heat rates in air increased from 0 to 30°C and decreased above 30°C. Heat rates measured isothermally at 23°C under decreased O2 or increased CO2 were lower than those in air with the lowest in 1 kPa O2 and 1 kPa O2 + 15 kPa CO2, Continuous temperature scans from 23 to 44.5°C under low O2 and high CO2 atmospheres produced lower metabolic heat rates than scans under air. Low O2 atmospheres produced the lowest ATP levels, and high concentrations of CO2 produced the highest ATP levels. These results indicate that heat treatments under controlled atmospheres have a dramatic effect on codling moth metabolism, low O2 prevents ATP synthesis, and high CO2 prevents use of ATP.