Moldy Mayhem in Store for Sugar
By Jan Suszkiw
February 17, 2000
A beneficial fungus that ravages
sugar beet root maggots could give farmers a new, natural defense against the
Though it is under half-an-inch long, the maggot's assaults on sugar beet
crops cost growers millions of dollars annually. Up to 38 percent of
Americas sucrose for condiments, baked goods, and other products comes
from the 1.5-million-acre sugar beet crop. Nearly half is treated with granular
insecticides like chlorpyrifos to kill root maggots, offspring of the fly
species Tetanops myopaeformis.
As they feed, maggots badly scar sugar beet roots, causing yield losses of
10 to 100 percent. Now, a new species of fungus--Syngliocladium
tetanopsis--may help curb the pest's sweet tooth. Chris Wozniak discovered
the fungus in 1994 and in September received a U.S. patent (#5,955,071).
His laboratory and field studies at the Agricultural Research Service indicate
Syngliocladiums spores can be sprayed or "seeded" into
soils as a biological pesticide. Dormant until a maggot makes contact, the
missile-shaped spores bore into their hosts body to germinate, destroying
organs and tissues.
In petri dish experiments, this killed 95 to 100 percent of exposed, newly
hatched maggots in three to five days. Eighty-five to 96 percent of older,
final-stage maggots died after several weeks. Yet scientists didn't observe a
similar fate in non-host insects, including beneficial lady bugs and lace wings
or pests like Colorado potato beetles.
Wozniaks chief colleague is Ann Smigocki, at ARS'
Molecular Plant Pathology
Lab in Beltsville, Md. ARS is the U.S.
Department of Agriculture's principal research arm. Wozniak, now at
EPA's Biopesticide and Pollution Prevention
Division, continues collaborating with Smigocki.
Theyre seeking a commercial partner to help develop the fungus into a
biopesticide product that growers can use as an alternative to conventional
insecticides. Coated onto beet seed, for example, it could be applied to soils
where maggot-killing chemicals can harm non-target insects, or endanger
groundwater. Use of the fungus, which doesn't infect plants, could also spare
seedlings from phytotoxic harm caused by some insecticides.
Scientific contacts: Ann Smigocki, ARS
Molecular Plant Pathology Lab, Beltsville, Md., phone (301) 504-5848, fax (301)
504-5320, email@example.com; or Chris
Wozniak, EPA Biopesticide and Pollution Prevention Division, phone (703)
605-0513, fax (703) 308-7026, firstname.lastname@example.org.