Submitted to: Acta Horticulturae
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/10/2002
Publication Date: 9/15/2002
Citation: Knight, A.L., Potting, R.P., Light, D.M. 2002. Modeling the impact of a sex pheromone/kairomone attracticide for management of codling moth (Cydia pomonella). Acta Horticulturae. 584:215-220. Interpretive Summary: The pear ester isolated from ripe pear is a highly attractive chemical for both male and female codling moth, a major pest of apple, pear, and walnut. Its discovery allows pest managers an opportunity to develop both monitoring and control tactics targeted at both sexes. Previously, only males were monitored and targeted with "attract and kill" control systems using the female -produced sex pheromone. We developed a simple population model that tracks the population of moths and resulting fruit injury in orchards treated with insecticide-treated stations baited with both the sex pheromone and the pear ester. The model demonstrated that the use of a female attractant greatly improves the effectiveness of the "attract and kill" technique. Our model output is compared with field data collected from apple plots treated with mating disruption and a grid of pheromone/kairomone baited insecticide-treated stations during 2001.
Technical Abstract: The pear-derived volatile, ethyl (2E, 4Z)-2,4-decadienoate is a potent, stable, and selective bisexual kairomone for codling moth, Cydia pomonella L. Its discovery creates a unique opportunity to develop monitoring and control tactics targeted for both male and female moths. Here we present a population model that compares the relative effectiveness of a male-only versus a bisexual attracticide. The model tracks daily changes in the population densities of pupae, males, and mated and virgin females using daily survival rates, and natural and insecticide- related mortality for eggs and larvae. The use of sex pheromones for mating disruption is included as a scalar variable affecting mating success. Mating is also influenced by the level of competition that occurs between virgin females and the insecticide-laced pheromone point sources (determined by their density and potency). The attractiveness of the kairomone lure is determined by the density and relative attractiveness of individual fruits within the cropping system. The potency (attractiveness and lethality) of the attracticide point sources declines at a constant rate over time. Our modeling results demonstrate that the use of a female attractant greatly improves the effectiveness of the "attract and kill" technique. Our model output is compared with field data collected from apple plots treated with mating disruption and a grid of pheromone/kairomone- baited insecticide-treated stations during 2001.