Fungi, Sex Drive Could Help Thwart Costly
By Hank Becker
March 4, 1999
Tiny, plant-parasitizing worms called nematodes could face a new set of
Fungi, plus the worms own sex drive and other tactics may help turn
the tables on the pests, according to the Agricultural Research Service, the
principal research agency of the U.S. Department
In the U.S, soil-dwelling nematodes cause estimated losses of $9 billion
annually from decreased food, fiber and ornamental production. But ARS
Laboratory in Beltsville, Md., is a hub for developing state-of-the-art
Among several projects with promising results, Beltsville scientists have
seen encouraging findings in studies with fungi and sex attractant chemicals.
The scientists collected 250 different fungi from areas of China where
soybeans were first cultivated. They screened many of the fungi in the lab to
help determine how they might be used against nematodes. One fungus, they
found, secretes compounds that reduce egg hatch of root-knot nematodes by 80
percent compared with a control group of nematodes.
Female nematodes emit attractants, or pheromones, to attract males. The
scientists found that some forms of the female soybean cyst nematodes sex
pheromone have potential to control the pests by disrupting their
communication. The pheromone may also be used to prevent young nematodes from
finding plant roots.
Root feeding by nematodes can weaken and sometimes kill plants. Thousands of
nematode species infect nearly every staple and horticultural crop. The soybean
cyst and root-knot nematodes are two of the worst culprits. The first attacks
soybeans; the second, more the gourmand, feeds on strawberries, most vegetables
and just about every other agricultural crop.
A story about the nematode studies appears in Marchs Agricultural Research magazine.
The story also is on the World Wide Web at:
Scientific contact: David J. Chitwood, ARS Nematology Laboratory,
Beltsville, Md., phone (301) 504-5660, fax (301) 504-5589,