High temperature alone and combined with controlled atmospheres for control of diapausing codling moth (Lepidoptera: Tortricidae) in walnuts

Abstract

High temperature alone and combined with controlled atmospheres were effective in killing diapausing codling moth larvae, Cydia pomonella (L.) Larvae were exposed to atmospheres of air 0.5% oxygen (O2) in nitrogen (N2), 0.5% O2 + 10% carbon dioxide (CO2) in N2 or to 98% CO2 in air, at temperatures of 39, 41, 43, or 45°C and 60% RH. LT95s were estimated for each atmosphere-temperature combination and fit to an asymptotic mathematical model to describe the effect of temperature. Higher temperature caused a more rapid killing. The decreasing order of effectiveness was 98% CO2, the two 0.5% O2 atmospheres, which were intermediate in effectiveness and not substantially different from each other and air.