Effects of irradiation on phenoloxidase levels in codling moth (Lepidoptera: Tortricidae) larvae

Laboratory trials were conducted to determine if changes in phenoloxidase, a common hemolymph component in insects, could be detected in codling moth, Cydia pomonella (L.). The 5 instars of codling moth were irradiated at doses of 0, 100, 300, 600, and 900 Gy and phenoloxidase levels were monitored at 0, 2, 4, and 6 d after treatment. The melanization method, protein electrophoresis, dot blot, and enzyme activity analyses were performed to determine phenoloxidase levels. No significant changes in the protein levels, enzymatic activity, or melanization rates in irradiated codling moth larvae were found. Although the melanization method may be adequate for determining whether larvae of the Caribbean fruit fly, Anastrepha suspensa (L.), were irradiated, it is not applicable to codling moth