Mass-trapping of Carpophilus spp (Coleoptera: Nitidulidae) in stone fruit orchards using synthetic aggregation pheromones and a coattractant: Development of a strategy for population suppression

Experiments were conducted in southern New South Wales to evaluate the potential of mass-trapping using synthetic aggregation pheromones and a coattractant as a control option for Carpophilus spp. in stone fruit orchards. A cordon of 54 pipe and 54 funnel traps (one trap of each type per perimeter tree) baited with pheromones of C. mutilatus and C. davidsoni and coattractant (fermenting bread dough) was maintained around an apricot orchard for three weeks prior to harvest. The incidence of Carpophilus spp. in ripe fruit in the center of the orchard was significantly reduced compared to a nearby orchard or the perimeter trees containing traps. A cordon of 16 water-filled Magnet funnel traps baited with pheromones of C. mutilatus and C. davidsoni and coattractant was placed around a 9 x 9 block of trees in a peach orchard (single traps on alternate perimeter trees). This trapping regime significantly reduced infestation of fruit baits by Carpophilus spp. in the center tree over a period of six weeks compared to fruit baits in trap trees and distant (100 m) control trees. However, cordons of eight pheromone traps within 1 m of single trees or a single trap adjacent to a tree increased Carpophilus spp. infestation of fruit baits by up to 7.5 x compared to trees without pheromone traps. Mass-trapping based on perimeter positioning of pheromone traps (at a yet to be determined distance from protected trees) appears to show potential as a control strategy for Carpophilus spp. in stone fruit orchards during fruit ripening and harvest but traps too close to trees must be avoided. Development of a strategy for population suppression is discussed with respect to trap type, efficacy, positioning, and density; pheromone and coattractant delivery systems; and orchard sanitation.