RESPONSE OF CADRA-CAUTELLA AND PLODIA-INTERPUNCTELLA (LEPIDOPTERA, PYRALIDAE) TO PHEROMONE-BAITED TRAPS

The effect of the presence of the Indianmeal moth, Plodia interpunctella (Hubner), on the capture of the almond moth, Cadra cautella (Walker), in pheromone-baited traps was evaluated. It was found that when both sexes of each species were released into a large warehouse simultaneously, the capture of male C. cautella was reduced to 5.5 +/- 0.8 in traps baited with a two-component lure as compared to 11.4 +/- 2.2 when only C. cautella were released. This decrease in response may have been caused by an inhibitory substance produced by the female P. interpunctella that affects the response of male C. cautella to the pheromone or confusion caused by an increase in the amount of pheromone present. This reduced response of C. cautella must be considered when using pheromone-baited traps to estimate population levels when both species are present.