2012 Annual Report
1a.Objectives (from AD-416):
1. Improve performance of the sterile insect technique (SIT) as an integrated control tactic against invasive and established lepidopteran pests by developing techniques that accurately measure field performance of released sterile moths and evaluating various laboratory and semi-field bioassays for their ability to predict field performance of sterile moths.
2. Advance the ability to integrate and monitor SIT in abatement/eradication programs against exotic/invasive Lepidoptera pests by developing methods and techniques to survey for the presence and density of both genders of target pest species, and to measure overflooding ratios and interaction of released sterile insects and wild insects; improving trapping and survey technology by developing calibrations that accurately predict pest population densities, trap efficiency, and efficacy of early detection programs for exotic pests; and, evaluating various marking techniques for identifying irradiated, released, and sterile moths and their interaction with the wild population, and measuring invasive pest movement and dispersal.
3. Increase our understanding of factors that affect insect pest invasiveness and establishment by examining and comparing mortality factors and host plant assemblages present in the insect pests’ native geographical range with the mortality factors and host plant assemblages present in the adventive geographical range and studying the ecology of invasive Lepidoptera pests to understand the role of voltinism, multiple strain introductions, flight propensity and capacity, and strain interaction with respect to dispersal and invasiveness.
1b.Approach (from AD-416):
We will conduct laboratory, greenhouse, and field research to improve the performance of the SIT as an integrated control tactic against invasive and established lepidopteran pests, advance the ability to integrate and monitor SIT in abatement/eradication programs against exotic/invasive Lepidoptera pests, and Increase our understanding of factors that affect insect pest invasiveness and establishment. This research, which emphasizes collaboration with State, Federal, and international cooperators, will result in improved management strategies for invasive insect pests that threaten U.S. agricultural and horticultural crops and natural ecosystems.
Invasive alien species are constantly threatening the abundant plant resources and the plant-based industries of the United States. Many of the most serious insect pests in the U.S. are introduced Lepidopterans. Action Agencies like the USDA-APHIS need pest control options and technologies such as the Sterile Insect Technique (SIT) that are effective, environmentally-benign, and socially-acceptable in order to provide a rapid response to newly invasive lepidopteran species in agricultural, urban and environmentally-sensitive areas. The SIT has been a useful tactic for combating lepidopteran pest species; however, implementing the SIT against an invasive species requires a high level of organization, substantial funding, and a considerable knowledge of the biology and ecology of the invasive pest. Improved knowledge, control tactics, technologies, strategies and assays are needed to reduce the costs and increase the successful implementation of the SIT against invasive Lepidoptera.
Research activities and experimental trials were conducted to optimize sterile insect technique (SIT) and inherited sterility tactics to manage/exclude invasive and exotic lepidopteran pest species. A significant effort was directed toward the improvement of a USDA-APHIS control/eradication strategy for the Argentine cactus moth, an invasive pest that poses a serious threat to native Opuntia cacti biodiversity and Opuntia-based industries in the southwestern USA and Mexico. In cooperative partnerships with USDA-APHIS, the International Atomic Energy Agency (IAEA), North American Plant Protection Organization, Florida Division of Plant Industry, and Secretaria de Agricultura, Ganaderia, Desarrollo Rural, Pesca Y Alimentacion (SAGARPA), Mexico, we continued developing and testing quality control bioassays, continued field trials to improve the pheromone lure for monitoring pest presence and population levels, improved handling and irradiation procedures for the SIT, and improved interstate and international shipping protocols that would preserve the quality of sterile moths to be used in SIT releases. Following the successful eradication of this pest from Mexico, the Bi-National Program established a mass-rearing insectary for the production of sterile moths at the Florida Department of Plant Industries Laboratory in Gainesville, Florida, to supplement the sterile moth production at the ARS-Crop Protection and Management Research Unit and eventually provide the moths for the operational program. To insure moth quality, laboratory and field bioassays were conducted on sterile moths from both insectaries. Data from the quality assessments and comparisons between the two insectaries were used as feedback mechanisms to make protocol changes both rearing and handling that improved moth quality and performance. The findings from these studies have been incorporated into the Bi-National Program against the cactus moth. Research has been initiated to develop new control technologies that offer sustainable management options for this pest in native desert ecosystems and commercial cactus production areas, including biological control and the disruption of pheromone communication systems (adult and larval). We identified a formulation of the synthetic adult sex pheromone that improved moth captures that contains only two of the original three components. Research has been initiated to identify the best formulation of a two-component pheromone blend for use in mating disruption trials. Also, in collaboration with scientists from SUNY, Cortland, New York, studies are ongoing to fully characterize a recently discovered trail-following pheromone in cactus moth larvae that may be crucial to the gregarious behavior required to successfully attack Opuntia. Other research activities have included the development and testing of bioassays to evaluate the quality of sterile moths for lepidopteran SIT programs. The work was conducted in South Africa using the codling moth as a model system with the cooperation of the Agricultural Research Council of South Africa and the IAEA.
Control strategy mitigates the threat of the invasive Argentine cactus moth in North America. Subsequent to its detection in south Florida in 1989, the Argentine cactus moth has had two incursions in Mexico, has expanded its range along the Atlantic Coast and west along the Gulf Coast to the barrier islands of Mississippi and bayous of Louisiana, and has become an imminent threat to many Opuntia cactus species valued as a food, a forage, a wildlife habitat, and a major plant group contributing to ecosystem structure and biodiversity. Following the successful eradication of this pest from Mexico using control tactics including the sterile insect technique, scientists from the USDA-ARS Crop Protection and Management Research Unit, Tifton, Georgia, in collaboration with USDA-ARS-CMAVE in Tallahassee, Florida and USDA-APHIS transferred mass-rearing technology to the Florida Department of Plant Industries Laboratory in Gainesville, Florida, and assisted in the establishment of an insectary supported by USDA-APHIS to supply sterile moths for the U.S.-Mexico bi-national cactus moth program. To insure moth quality, laboratory and field bioassays were developed and conducted on sterile moths, and data were used as feedback mechanisms to make protocol changes in both rearing and handling that improved moth quality and performance. USDA-APHIS and SAGARPA, Mexico continue to use these methods and tactics in the operational program that is part of an ongoing U.S.-Mexico bi-national campaign against this invasive pest to mitigate the further westward expansion or outbreak of pest populations.
Carpenter, J.E., Blomefield, T., Vreysen, M. 2012. A flight cylinder bioassay as a simple, effective quality control test for the codling moth, Cydia pomonella in the context of the sterile insect technique? Journal of Applied Entomology. DOI:10.111/j.1439-0418.2012.01771.x.
Blomefield, T., Carpenter, J.E., Vreysen, M. 2011. Quality of mass-reared codling moth (Lepidoptera: Tortricidae) after long distance transportation: 1. Logistics of shipping procedures and quality parameters as measured in the laboratory. Journal of Economic Entomology. 104(3):814-822.
Jezorek, H., Stiling, P., Carpenter, J.E. 2011. Ant predation on an invasive herbivore: Can an extrafloral nectar-producing plant provide associational resistance to Opuntia individuals? Biological Invasions. 13:2261-2273.
Grasela, J.J., McIntosh, A.H., Ringbauer Jr, J.A., Goodman, C.L., Carpenter, J.E., Popham, H.J. 2012. Development of cell lines from the cactophagous insect: Cactoblastis cactorum (Lepidoptera: Pyralidae) and their susceptibility to three baculoviruses. In Vitro Cellular and Developmental Biology - Animals. 48:293-300.