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Progress toward first repellent for stinkbug

October 14, 2010 – Help
may be on the way for millions of people bugged out about the invasion of stink
bugs.

October 14, 2010 – Help
may be on the way for millions of people bugged out about the invasion of stink
bugs.

Scientists have reported a
key advance in efforts to develop the first commercial repellent for stinkbugs,
which are emerging as a major nuisance and a devastating pest to some farm
crops. They identified a natural substance in a fungus that infects a common
weed and found that it shows potential as the first stinkbug repellent.

Their study appeared in
ACS’ Journal of Agricultural and Food Chemistry.

Hiromitsu Nakajima and
colleagues note that stinkbugs are no strangers to Japan. In contrast, the
brown marmorated stinkbug seems to have gotten a foothold in the U.S. around
1998, and since then has spread, especially in the mid-Atlantic states,
invading homes and damaging fruit and vegetable crops. The nuisance bugs get
their name from the skunk-like odour they emit when crushed or annoyed. Farmers
are trying to control the pests using a variety of commercial insecticides,
which kill the bugs. A stinkbug repellent could be just as effective in keeping
the bugs at bay, but no reports on development of such materials have appeared
in scientific journals, they say.

The scientists isolated a
fungus from the green foxtail plant, a common weed found the U.S. and other
countries. The fungus lives inside the plant and appears to help protect the
foxtail from insect pests and disease. In laboratory tests, extracts of the
fungus strongly repelled the white-spotted stinkbug, which they used as a test
subject because it is easy to collect, maintain, and handle under laboratory
conditions. The scientists identified an ingredient in the extract that is
capable of repelling up to 90 per cent of stinkbugs and suggest that this
chemical could be part of the first repellent for controlling stinkbugs. The
substance repelled the stinkbugs as effectively as naphthalene, an ingredient
in mothballs and a gold standard for measuring the effects of insect
repellents. A chemically modified version of the substance was almost twice as
effective napthalene.