Assessing the efficacy of a multispecies pheromone dispenser for the control of tortricids in apple orchards: a three-year evaluation
Abstract: We tested the possibility of using a single device for the pheromone disruption of a number of lepidopteran pests of apple in Sweden. Experiments were carried out in single conventional orchards of different size equipped with plant hedges and surrounded by variable landscapes. An increasing inhibition of the male flying activity by the synthetic airborne pheromone was measured over the three-year period for the majority of the tested species. The reduction in the larval activity of the corresponding species varied in accordance with the management and the surrounding of the orchard. Experiments in field cages showed a significant interference effect of the synthetic pheromone formulation on location of calling females by released males. The release of each component from the device was continuous over the entire flight period of the monitored species with a partial residual release in the following season. According to our results, we recommend the use of the tested device as a tool to reduce the field population of lepidopteran pests as well as to diminish the load of chemical insecticides in orchards. Due to the variability of the results in relation to single orchard features, field scouting needs to be considered as a necessary support to growers.