Title: Dispenser and trap design affect the effectiveness of sex pheromone on trap capture of dogwood borer Authors
Submitted to: Journal of Chemical Ecology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 8, 2013
Publication Date: February 15, 2013
Citation: Zhang, A., Leskey, T.C., Bergh, C., Walgenbach, J. 2013. Dispenser and trap design affect the effectiveness of sex pheromone on trap capture of dogwood borer. Journal of Chemical Ecology. 39:390-397. Interpretive Summary: The dogwood borer (DWB) causes serious problems on woody ornamental, nut, and fruit trees. Since the 1980’s, it has been widespread in commercial apple orchards in Northeast America. In severe cases, it can reduce apple tree growth and even lead to tree death. In a previous study, we identified the female sex attractant that attracted males for mating. In the current study, we evaluated different traps and dispensers that could affect the effectiveness of the sex attractant on capture of male DWB, determined release rates of sex attractant in the field and laboratory conditions, and indentified one potential attractant inhibitor. This information will enable scientists and growers to develop more efficient DWB population monitoring tools, optimize insecticide spray timing, reduce insecticide application, decrease impact on natural enemies in apple orchard habitats, and facilitate ongoing IPM programs to manage DWB populations.
Technical Abstract: The capture of dogwood borer (DWB), Synanthedon scitula Harris (Lepidoptera: Sesiidae), was evaluated in field trapping studies using wing-style sticky traps baited with rubber septum or polyethylene vial dispensers containing the most effective sex pheromone ternary blend [86:6:6 v:v:v (Z,Z)-3,13-octadecadienyl acetate : (E,Z)-2,13-octadecadienyl acetate : (Z,E)-3,13-octadecadienyl acetate] in apple orchards in West Virginia, Virginia, and North Carolina. Traps baited with a polyethylene vial dispenser captured significantly more male DWB than those baited with a rubber septum dispenser during the first two months. However, captures in vial-baited traps decreased considerably after two months, possibly due to the potential antagonistic effects of 3,5-di-tert-butyl-4-hydroxy acetophenone that diffused from the polyethylene vials deployed under field condition. Conversely, traps baited with rubber septum dispensers reliably captured DWB males for at least 6 months with significantly more captures than traps baited with vial dispensers during the last four months of the flight season. Therefore, the rubber septum dispenser is the recommended release vehicle for DWB pheromone for season-long monitoring. A release rate study using lab and field-aged dispensers demonstrated that the DWB sex pheromone was desorbed from polyethylene vials and rubber septum dispensers following first order kinetics, with half-life (t1/2) values of 1.6 and 10.7 months, respectively. Several trap designs including wing and delta style sticky traps and white and green “bucket” style traps baited with rubber septum dispensers were compared for their effectiveness at capturing DWB in commercial apple orchards. Bucket traps clearly demonstrated greater trapping efficiency when moth populations were high and quickly saturated the sticky surfaces of 1C and delta traps. However, among commercially available traps tested, no particular trap design consistently resulted in increased captures likely because of differences in capture mechanisms and maintenance needs.