Amarillo, Texas
August 11, 2005
Diseases resembling Asian soybean rust have
caused concerns among Panhandle producers in recent weeks.
However, Dr. Tom Allen, assistant research scientist and head of
the Plant Disease Diagnostic Laboratory with
Texas Agricultural
Experiment Station, said Asian soybean rust has not yet
spread to the Texas Panhandle.
"Also, we want to make sure everyone understands there is only
one kind of soybean rust. It is known as Asian soybean rust,"
Allen said.
In Asia, where soybean rust was first found, losses of up to 70
percent were reported. The United States' first confirmation of
disease was in Louisiana in 2004.
It has since been found in Alabama, Florida, Georgia and
Mississippi, although most reports have identified susceptible
weed hosts, and in soybean "sentinel plots," Allen said. It has
only been found in one producer's field in Florida, he said.
Sentinel soybean plots serve as an early indicator of disease
development in each region, Allen said. This allows researchers
and producers to respond to the disease in a timely manner. Most
soybean sentinel plots are observed for soybean rust on a
frequent basis, he said.
This year, the U.S. Department of Agriculture implemented
sentinel plots in more than 30 states, Allen said. Soybean plots
were planted in the spring and will be observed throughout the
growing season for soybean rust.
One problem with diagnosis is several other soybean diseases are
similar in appearance, he said. Brown spot, bacterial blight,
bacterial pustule, frogeye leaf spot and downy mildew all
produce "rust-like" lesions on soybean leaves.
"The naked eye will not be able to easily determine the
differences; however, in the diagnostic laboratory these
diseases can be differentiated," Allen said.
Producers with a problem area should send plant samples to:
Texas High Plains Plant Pathology Laboratory, c/o Tom Allen,
Texas A&M University System Agricultural Research and Extension
Center, 6500 W. Amarillo Blvd., Amarillo, Texas 79106.
Each sample should be double bagged in self-locking plastic
bags, Allen said. Send samples by the fastest method possible,
ideally overnight, or bring them by the Experiment Station in
Amarillo. Allen can be reached at
(806) 677-5600.
When sending a sample, be sure to send more than one leaf, he
said. Do not expose the samples to direct sunlight or high
temperatures inside a plastic bag prior to mailing.
Producers can track the soybean rust situation at
http://www.sbrusa.net. This
Web site monitors where the disease is present and where
researchers have scouted for the disease and not found it
present, Allen said. |