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By Brad Haire
University of Georgia

University of Georgia farm experts will begin planting soybean
plots throughout Georgia next month to act as early detectors
for an aggressive crop disease first reported across the
Southeast last fall.

Asiatic soybean rust was reported in the United States in
November. Tropical storms in September are believed to have
picked up spores in South America and delivered them to
Southeastern states.

It was first reported in soybean research plots in Louisiana.
Later, it was identified in farm fields in Alabama, Arkansas,
Florida, Georgia, Mississippi, Missouri, South Carolina and
Tennessee.

This year?

The disease hit late in the 2004 growing season. It didn’t
cause
any damage to the crop. But Southeastern soybean farmers may
not
be as lucky this year, said Bob Kemerait, a plant pathologist
with the UGA Extension Service.

“It’s not guaranteed,” Kemerait said. “But it’s very likely
that
it will hit us this year.”

Asiatic rust is a tropical fungal disease. Cold temperatures
kill it.
It probably didn’t survive Georgia’s winter, he said.

“But it’s likely that it did survive in south Florida or in the
Caribbean,” he said. “It could be reintroduced very quickly.”

It’s carried by wind, he said, and can spread as fast as 300
miles a day. The disease attacks a plant’s leaves, reducing
yields or killing the plant.Control early

The UGA Extension Service will monitor 15 to 20 plots on
research stations and farms across Georgia, said Phil Jost, a
UGA Extension agronomist.

“We hope they will be like canaries in the mineshaft,” Jost
said, “where we will detect the disease first on these plots
before it’s picked up in growers’ fields.”

The disease can be controlled with fungicides, he said. “But
the
key will be to control it on time and quickly.”

Georgia growers usually don’t spray soybeans with fungicides.
But they’ll have to, he said, if this disease gets in fields.
But it’ll cost $20 to $30 per acre. This could eat up any
profit
for some farmers.

“Soybeans have traditionally been a cheap and easy crop to grow
for Georgia,” Jost said. “This rust changes both of those.”

Soybeans are a more highly valued crop in the Midwest, where
most of the U.S. crop is grown. Kemerait and Jost will
coordinate and share information from Georgia’s Asiatic soybean
rust monitoring program with the U.S. Department of
Agriculture,
other Southeastern states and research institutions in the
Midwest. If the disease shows up, farm officials there can
implement their control programs.

Georgia farmers planted 270,000 acres of soybeans last year.
But
they’ll probably plant fewer acres this year, due to the rust
threat and lower expected prices, Jost said.

The disease can hurt other Georgia crops, such as snap beans
and
Southern, pole and English peas. But they’re not as susceptible
as soybeans, said David Langston, a UGA Extension plant
pathologist. If left unchecked, though, it could cause
problems.

Georgia’s pea and bean crop was worth $77 million in 2003. Snap
beans accounted for about $60 million of that. Georgia ranks
second in the United States in snap bean production. Most of
Georgia’s snap beans are sold for fresh markets.

Georgia farmers who plant peas and beans already spray their
crops at least once for other fungal diseases, Langston said.
This should also take care of Asiatic soybean rust.

But farmers need to watch for the disease, he said, and be
ready
to respond with more fungal sprays if it gets a foothold in a
field.