Relationship between males caught with low pheromone doses and larval infestation ofArgyrotaenia pulchellana

Sex pheromone traps forArgyrotaenia pulchellana Haw. (Lep. Tortricidae) were loaded with two low pheromone doses (0.1 and 0.01 mg) and tested in apple and pear orchards of northern Italy's Emilia-Romagna Region to estimate the relationship between male catches and subsequent larval infestation. While the lower dose captured fewer males, it registered an enhanced correlation to larval populations and a decrease in the number of episodes of high catches associated with no infestation. In all likelihood, the pheromone traps baited at the lower dose have a smaller active space and captured only makes within the orchard. Lures with 0.01 mg of pheromone can be replaced every 6 weeks, just as the 1 mg lures now in widespread use in Italy. A threshold of 65 adults captured from the beginning of flight is proposed for the Emilia-Romagna IPM project.