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WASHINGTON (AP) -- New research shows that a beneficial fungus that
ravages sugar beet root maggots could give farmers a new, natural
defense against the pest.
While it's less than a half-an-inch long, the maggot's assaults on
sugar beet crops cost growers millions of dollars each year.
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 percent 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.
His laboratory and field studies at the U.S. 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 lab experiments this killed nearly all exposed, newly hatched
maggots in three to five days. Up 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.
They're 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. |