Des Moines Register
05-22-07
Fear of soybean rust in Iowa withers, officials say
The disease was found on one leaf, said to be from Mahaska County, but that's
all, Iowa's ag chief says.
By JERRY PERKINS
REGISTER FARM EDITOR
State officials are now doubting a report that Asian soybean rust was found in
Iowa.
U.S. Department of Agriculture investigators are looking into whether an infected
leaf reportedly from Mahaska County actually came from outside the state, Iowa
Secretary of Agriculture Bill Northey said Monday.
Officials with the Iowa Department of Agriculture and Land Stewardship and Iowa
State University said they were unable to find additional traces of Asian soybean
rust in the Mahaska County field or in neighboring fields.
"We did verify that one leaf submitted in a plant sample was infected with Asian
soybean rust, but how it got into Iowa still needs to be determined," Northey said.
"After careful examination of the materials collected to date, we believe no Asian
soybean rust infection occurred during the 2006 growing season in Iowa."
Asian soybean rust cuts yields but can be controlled with fungicides. Control can
be expensive and difficult.
Paul Feeney, spokesman for the Office of Inspector General, the investigatory
branch of the Agriculture Department, said it is department policy to not comment
on investigations.
Iowa Department of Agriculture and ISU officials declined to release the name of
the farm where the leaf was said to come from and the name of the person who
submitted the sample to the ISU Plant Disease Clinic.
On March 8, the sample containing soybeans and leaves harvested in Mahaska
County in 2006 was submitted to the clinic. Tests at the clinic showed that a leaf
in the sample was infected with Asian soybean rust.
On March 12, the Agriculture Department confirmed that the leaf was infected
with the rust disease.
It would have been the first recorded occurrence of Asian soybean rust in Iowa.
Widespread Asian soybean rust contamination broke out in 2002 in Brazil. The
rust was first reported in the United States in 2004. Plant scientists believe the
disease entered the United States on winds from the south.
The disease mostly has been contained to Southern states, although Asian
soybean rust has been reported to have traveled as far north as Illinois and
Indiana.
Greg Tylka, spokesman for the Iowa Soybean Rust Team, said soybean
seeds, pods, stems and a single leaf were brought to the plant disease clinic by a
person who said he believed the sample might be infected with soybean rust.
After the tests showed Asian soybean rust present on a leaf in the sample, a
team from the Iowa Department of Agriculture and ISU talked to the grower
whose field the sample was said to come from and visited the field, Tylka said.
"Iowa State plant pathologists couldn't verify that there was soybean rust in
that field," Tylka said.
"We're real confident on the scientific side that if rust was in the field it reportedly
was in, we should have seen something in the field or in the bin. All our evidence
leads us to believe it wasn't in Iowa in 2006."
Tylka said the incident points out the danger that a false alarm can cause:
People will eventually ignore a real report, like the townspeople who ignored the
little boy who cried "wolf."
"Of course, in the story, the wolf eventually showed up," Tylka said. "Let's be
prepared when the wolf shows up."
Detecting soybean rust
Growers are encouraged to consult with a "first detector" if they suspect plants
might have soybean rust. The service is free.
FIRST DETECTORS: The Iowa Soybean Rust Team trained 600 "first detectors"
who can examine leaf samples and decide whether they warrant further analysis
by Iowa State Extension or other scientists. Detectors' names and contact
information are available on the Iowa Soybean Rust Team's Asian soybean rust
Web site, www.soybeanrust.info, and at county Extension offices.
SENTINEL PLOTS: Iowa State University has planted 20 sentinel soybean plots
in Iowa as part of a national sentinel system that reaches from Florida and Texas
to the Midwest. The plots are monitored during the soybean growing season to
inform producers of any threat.
Farm Editor Jerry Perkins can be reached at (515) 284-8456 or
jperkins@dmreg.com