Electrodes Help Find Beetles Favorite
February 7, 2000
Several chemical scents that attract
Colorado potato beetles have been discovered by
Agricultural Research Service
scientists. They attached tiny electrodes to the tips of beetles antennae
so they could monitor the pests sensitivity to the scent of potatoes.
Colorado potato beetles are the potato crops most destructive pest,
costing growers millions of dollars in chemical control and crop losses. For at
least 73 years, scientists have been searching for the scent that attracts this
yellow and black multi-colored bug to solanaceous plants.
Entomologist Joseph C. Dickens with ARS
Vegetable Laboratory in
Beltsville, Md., made the find while exposing the insects to different potato
leaf aromas and allowing them to choose the scents they preferred.
When Dickens offered the beetles a choice between one of the scents and
potato foliage, the beetles were terribly confused and could not tell the
difference between the two attractive scents. He monitored the insects
responses to both real and synthetic scents.
In preliminary field tests, the beetles were captured with a synthetic lure
containing a mixture of these compounds. According to Dickens, no one had ever
caught a Colorado potato beetle with a synthetic lure before. They have
identified at least five different synthetic blends that are attractive to the
insects in laboratory tests--and that may be attractive in the field as well.
From this research, naturally-occurring chemical signals could be used to
monitor and control pest populations.
Dickens is also investigating how chemical scents, which are emitted when
the beetles chew on plants, might help attract potato beetle predators.
ARS is the chief scientific agency of the U.S. Department of Agriculture.
More information on this research appears in the February issue of Agricultural Research magazine.
Scientific contact: Joseph C. Dickens, ARS Vegetable Laboratory,
Beltsville, Md., phone (301) 504- 8957, fax (301) 504-5555,