

Tracking the Spread of the Russian Wheat
Aphid Goes High-TechBy Hank Becker December 29, 1999Tracking the population dynamics of the Russian wheat aphid--one of the most
highly mobile pests in the central Great Plains--is going high-tech. Agricultural Research Servicescientists at Stillwater, Okla., extensively studied and modeled the pest in
wheat and non-cultivated wheat areas to determine the effects of agroecosystem
and landscape on its population dynamics. Now, they can evaluate and develop
better field- monitoring methods for the aphid for use in ecological studies
and integrated pest management systems.  Related story: Fungus v. aphid (Sept. 1999)
Since invading the United States in 1986, the
green, 1/16-inch-long aphids have cost more than $850 million in insecticide
and crop losses. While conventional breeding has produced aphid-resistant wheat
varieties, they aren't yet widely grown and are not adapted to all areas where
the aphids are pests. Now that the scientists know how the Russian wheat aphid develops new
populations and have successfully developed simulation models predicting its
within-site population dynamics, theyre ready to extend modeling to
landscape and regional scales. The state-of-the-art approach to understanding this pests dynamics
includes organizing and analyzing remotely sensed geographical data from
LandSat, constructing descriptions of its habitat both in space and time, and
meshing models of its population dynamics with areawide habitat data. To this end, they have obtained, classified, and collated LandSat,
meteorological, and other pertinent data for seven states in the central Great
Plains. The LandSat data provides timely, high-quality, visible and infrared
images of all landmass and near-coastal areas. These images are used
extensively to study global change, geology and forestry, as well as
agriculture. The scientists goal is to construct and validate a regional outbreak
risk assessment system for the aphid. Theyll use this model to analyze
the feasibility of managing the pest areawide and predict risk of population
outbreaks at broad geographical scales. ARS is the chief research agency of USDA. Scientific contact: Norman C. Elliott, ARS
Plant Science and Water Conservation
Research Laboratory, Stillwater, Okla., phone (405) 624-4141, fax (405)
624-4142, [email protected]. U.S. Department of Agriculture | |