Hot-water effect on mortality of Cydia pomonella (Lepidoptera: Tortricidae)

The effect of direct immersion in hot water at 43-49 degrees C on the mortality of 1-, 3-, and 5-d-old eggs and 1st, 3rd, and 5th instars of the tortricid Cydia pomonella (L.) was evaluated. The 1st instar was more tolerant than all other life stages of C. pomonella at all of the temperatures tested. Third and 5th instars were typically the next most tolerant life stages, and hence larvae were more tolerant than eggs. There were no significant differences between the responses of eggs of different ages. C. pomonella is more tolerant than other New Zealand tortricid pests of quarantine concern when exposed to hot water in the absence of the host fruits.