"Because so few soybean producers in
the state have ever had to use foliar fungicides to manage diseases,
many of them have been inquiring about Section 18 supplemental
labels, as well as the toxicity profiles for these fungicides," said
Bruce Paulsrud, specialist in pesticide safety education and plant
pathology with University of Illinois Extension.
He points out that three families of
fungicides have been labeled for managing soybean rust in soybeans
as of the end of January 2005 -- triazoles, strobilurins and the
The triazoles include myclobutanil,
which is used in Laredo EC and Laredo EW; propiconazole, which is
used in Bumper, PropiMax EC, Stratego and Tilt; and tebuconazole,
which is used in Folicur.
The strobilurins include
azoxystrobin, which is found in Quadris; pyraclostrobin, which is
found in Headline; and trifloxystrobin, which is found in Stratego.
The nitriles include chlorothalonil,
which is used in Bravo WeatherStick, Echo 720 and Echo 90 DF.
"All of the triazoles and Stratego
do not currently have soybean as a crop on their regular labels
under Section 3," Paulsrud said. "Each of them, however, was granted
a Section 18 supplemental label that allows the product to be used
on soybean to protect against soybean rust."
Paulsrud emphasizes that these
Section 18 fungicides are not new and untested. All of them already
have full registration with the U.S. Environmental Protection Agency
for use on other food crops.
"If you wish to use a pesticide as
directed by a Section 18 supplemental label, you must have a copy of
the supplemental label in your possession at the time of use,"
Paulsrud said. "You can obtain these labels from your pesticide
dealer, online label sites or directly from the pesticide
manufacturer. Remember that these labels specifically state where,
how and for how long the product may be used."
He notes that these Section 18
fungicide labels clearly state that a maximum of two total
applications using approved Section 18 products collectively are
allowed under this soybean rust Section 18.
"The bottom line is that you may not
spray any Section 18 product or combination of these products more
than twice per acre per season," Paulsrud said. "Like any pesticide,
fungicides can be dangerous, so it's important to read and follow
the instructions provided on the product container or label."
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Paulsrud points out
that the danger of any product is evaluated not only by its toxicity
but also by the degree of exposure to the product. He suggests
looking at the product label and material safety data sheet when
evaluating the relative danger of any pesticide.
"The mentioned triazole fungicides
are all general-use products," he said. "They have signal words
ranging from 'caution' to 'danger.' Many of them can cause eye
injury, and most are toxic to fish and aquatic species."
The strobilurins labeled for Asian
rust also are all general-use products. They have signal words
ranging from 'caution' to 'warning.' Several of them can cause eye
injury, and all of them are toxic to fish and aquatic invertebrates.
The chlorothalonils are general-use
products with signal words ranging from 'caution' to 'danger.' They
can cause eye injury and are toxic to aquatic invertebrates and
"The pesticide label and
instructions provide specific and EPA-approved statements to help
protect yourself, the environment and the public," Paulsrud said.
"It is important to use caution when interpreting toxicity
information from various other sources. Evaluating the usefulness
and meaning of human health and environmental studies is often
particularly troublesome. We are all too often bombarded by bits of
evidence and premature conclusions."
He adds that that well-designed and
well-executed health and environmental studies take a good deal of
"Accurate conclusions are drawn from
the 'weight of the evidence' from all studies rather than individual
studies," Paulsrud said. "It is good for those of us
non-toxicologists to be watchful but also careful that we don't draw
premature and inaccurate conclusions."
Additional information on how the
U.S. EPA helps to ensure a safe environment and food supply is
available on the Internet at
of Illinois news release]