Des Moines, Iowa
July 7, 2008
After three complete growing
seasons of Asian soybean rust (ASR) in the U.S., there are signs
the disease can potentially expand northward, and experts with
Pioneer Hi-Bred, a DuPont
business, recommend growers closely monitor soybean fields for
any signs of the disease.
“Growers need to continue to be aware of ASR, and while we
haven’t heard about any significant problems at this time,
regular scouting for the disease is recommended,” says Paul
Stephens, Pioneer research fellow.
Asian soybean rust, a wind-borne fungal disease, is an
aggressive pathogen with the ability to significantly reduce
yields. If the disease is scouted early, a fungicide application
is effective.
To determine if the disease is present, look on the underside of
the leaf, starting from the middle to lower portion of the
plant. The leaf will have red to tan lesions with small spores.
The spores are a confirmed sign of rust.
In the U.S., the pathogen survives winter on an overwintering
host south of the freeze line. Throughout the growing season,
the disease will continue to push further north into the
Midwest.
“If the Midwest sees ASR, most likely it will be late in the
growing season,” says Stephens. “If a grower knows rust is
suspected south of his or her operation, and conditions are
conducive – cloudy, cool and wet – a fungicide should be
applied. The earlier the application is applied, the better the
protection. Once soybean rust destroys leaf tissue, significant
yield loss has occurred.”
One control option for growers is DuPont™ Punch™ fungicide which
has been granted a section 18 quarantine exemption from the EPA
in several states to control ASR. Punch™ provides preventive and
curative control of ASR in both high and current low disease
pressure. It contains flusilazole, a unique broad spectrum
fungicide that provides superior residual control, rapid
penetration of waxy leaves and gradual systemic redistribution.
For more information on where to purchase Punch™, call
1-800-342-5247 or contact your local DuPont representative.
Pioneer has an intensive molecular marker research program to
incorporate into soybeans native genes for resistance to ASR to
protect growers against the threat of yield loss. The program is
identifying ASR-resistance genes out of the entire Pioneer
soybean germplasm collection then moving them into elite
products, combining ASR resistant genes with Accelerated Yield
Technology (AYT™) to develop the complete Pioneer package.
Pioneer plans to commercialize soybean varieties carrying
multiple sources of ASR resistance by 2013 in the U.S.
ASR is a diverse pathogen and can change or evolve in some
environments to overcome a resistance gene. The potential for
different isolates or ‘races’ to evolve increases the challenge
for developing durable resistance. Experiences with soybean rust
in South America and Asia have demonstrated that single genes
for ASR resistance can be overcome.
“Because rust can change so quickly and without warning, Pioneer
is evaluating stacking rust-resistance genes,” says Stephens.
“Pioneer’s strategy is to stack resistance genes to offer a
broader type of resistance.”
For high disease environments, stacking genes of resistance is
more effective than a single gene defense.
“This type of defense against ASR offers growers a new level of
protection and provides greater insurance against yield loss for
soybean growers who may experience ASR,” says Stephens.
To monitor Asian soybean rust, visit
http://www.usda.gov/soybeanrust. If ASR is suspected, contact
your local Pioneer sales professional or agronomist. Soybean
tissue samples can be submitted to the Pioneer Diagnostic Lab
(7300 NW 62nd Ave., Reid #33C, Johnston, IA 50131) to determine
the presence of ASR. Growers can work with their local Pioneer
representative for submission directions.
Pioneer Hi-Bred, a DuPont business, is the world’s leading
source of customized solutions for farmers, livestock producers
and grain and oilseed processors. With headquarters in Des
Moines, Iowa, Pioneer provides access to advanced plant genetics
in nearly 70 countries.
DuPont is a science-based products and services company. Founded
in 1802, DuPont puts science to work by creating sustainable
solutions essential to a better, safer, healthier life for
people everywhere. Operating in more than 70 countries, DuPont
offers a wide range of innovative products and services for
markets including agriculture and food; building and
construction; communications; and transportation.
DuPont™, Punch™ and AYT™ are trademarks or registered trademarks
of DuPont or its affiliates.
DuPont™ Punch™ soybean fungicide is available for use on
soybeans for the control of Asian soybean rust through Section
18 exemptions. The exemptions are valid through February 7,
2010, for use of Punch™ in the states of Minnesota and South
Dakota and through June 15, 2010, in Alabama, Arkansas,
Delaware, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky,
Louisiana, Maryland, Michigan, Mississippi, Missouri, Nebraska,
North Carolina, North Dakota, Ohio, Okalahoma, South Carolina,
Tennessee, Texas and Virginia. State list may not be complete;
approval is pending in other states. Do not make more than two
applications of flusilazole-containing products to soybeans per
season. A maximum of three total applications using approved
Section 18 products collectively is allowed under the Asian
Soybean Rust Section 18, except in certain states, where a
maximum of two total applications of Section 18 products is
allowed. Read and follow the label use directions specific to
your state. Punch™ is not registered for sale or used in the
United States and may only be used in accordance with the
specific provisions, restrictions and limitations in the Section
18 label for your state. The Section 18 label must be in the
possession of the user at the time of application. For the name
and address of retailers who stock Punch™, call 1-888-6DuPont
(638-7668), or contact your local DuPont representative. |
|
