Author
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Thorpe, Kevin |
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Submitted to: Annual Gypsy Moth Review Proceedings
Publication Type: Proceedings Publication Acceptance Date: 12/31/2001 Publication Date: 10/1/2002 Citation: Thorpe, K.W. 2002. Gypsy moth mating disruption research: from bows and arrows to electroantennograms. Annual Gypsy Moth Review Proceedings. Interpretive Summary: The gypsy moth is a serious pests of trees in forested and residential areas of the northeastern United States. One way to control this pest is by permeating its environment with its sex pheromone, disparlure. There is increasing interest in the use of this method, known as mating disruption, because of concern over the potential adverse ecological impacts of insecticide spraying. Unlike most other control methods available for thi pest, mating disruption only affects the gypsy moth and therefore has no unintended environmental impacts. This paper reviews research efforts over the past 30 years to develop and refine methods to manage gypsy moth populations using aerial applications of mating disruptants. Techniques for evaluating the effectiveness of treatments are discussed, and a new tool for directly measuring the airborne concentration of disparlure using a portable electroantennogram device (EAG) is described. Data are presented showing that the measured concentration of disparlure was lower in plots treated at a reduced rate, and that the disparlure concentration was higher in the tree canopy than near the ground. The information presented in this report will help government agencies, gypsy moth control specialists, and other persons interested in gypsy moth mating disruption programs understand the history of mating disruption research, the limitations of current technology, and how the EAG can be used in operational mating disruption programs. Technical Abstract: Aerial application of mating disruptant formulations to manage gypsy moth populations was used on over 40,000 hectares in 2000. Field experiments to develop and test the mating disruption technique began in 1971 and have continued to the present time. A number of methods to evaluate mating disruption have been developed, including trap capture in traps baited with hgypsy moth sex pheromone, evaluations of the mating success of sentinal females, and assessments of gypsy moth population trends in treated areas. A potentially useful new evaluation method which involves the measurement of pheromone concentrations in the air in treated plots using a portable electroangennogram device (EAG) is described. An EAG was used in association with mating disruption trials in Virginia in 2000 to determine if the device could detect differences between plots treated with a standard mating disruption treatment (75 g of pheromone per hectare) versus sthose treated with one half of that dose. While both treatments successfully disrupted mating to the same degree, the EAG measured significantly lower concentrations of pheromone in the plots receiving the lower dose. On average, pheromone concentration was higher in the canopy than near the ground. Potential sources of variability in the EAG measurements are identified and future lines of research are suggested. |
