History of Soybean Rust:
Soybean rust was first observed in Japan in 1902. After it got a foothold, the fungus began to spread quickly:
- 1934 — Other Asian nations and Australia
- 1951 — India
- 1996 — Kenya, Rwanda and Uganda
- 2000 — Mozambique
- 2001 — Paraguay
- 2002 — Parts of Brazil and northern Argentina
- 2003 — Brazil
- 2004 — Continental United States
What is the Missouri Department of Agriculture Doing?
Since the discovery of soybean rust in other countries, and considering the fact that the disease is a highly contagious air-borne pathogen, it was not a question of "if," but a question of "when" the disease would be discovered in the U.S.
For the past two years, the U.S. Department of Agriculture (USDA) Animal and Plant Health Inspection Agency (APHIS) has been working with state departments of agriculture to develop a strategic plan for combating soybean rust. The Missouri Department of Agriculture (MDA) has adopted this National Strategic Action Plan. Also, MDA continues to take appropriate preparatory steps in educating producers and encouraging the U.S. Environmental Protection Agency (EPA) to approve additional fungicides that would help with the treatment of soybean rust.
In addition to the strategic plan, Section 18 of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) authorizes EPA to exempt a state or federal agency from the provisions of FIFRA if EPA determines that emergency pest conditions exist.
Current Registered Pesticides for Use to
Control Asian Soybean Rust
| Common Name: | Active Ingredient: |
| Quadris | Azoxystrobin |
| Pristine (with pyraclostrobin) | Boscalid |
| Bravo Weather Stick; Echo 720; Echo 90DF; EQUUS 720 SST; EQUUS DF | Chlorothalonil |
| Headline | Pyraclostrobin |
Current ingredients approved for emergency use until November 10, 2007:
Pesticides Approved for Emergency Use
| Common Name: | Active Ingredient: |
| Tilt; Propimax; Bumper | Propiconazole |
| Folicur 3.6F; Orius 3.6F; Uppercut | Tebuconazole |
| Laredo EC and Laredo EW | Myclobutanil |
| Stratego | Trifloxystrobin + Propiconazole |
| Domark 230ME | Tetraconazole |
| Quilt | Propiconazole + Azoxystrobin |
| Headline SBR | Pyraclostrobin + Tebuconazole |
| Alto 100SL | Cyproconazole |
What are the Symptoms of Soybean Rust?
- Small lesions on the lower leaves that increase in size and change from
gray to tan or reddish brown on the undersides of the leaves.
- Lesions are most common on leaves but may occur on petioles, stems and
pods.
- Tan lesions, when mature, consist of small pustules surrounded by slightly
discolored necrotic area with masses of tan spores on the lower leaf surface.
- Reddish brown lesions have a larger reddish brown necrotic area, with a limited number of pustules and few visible spores on the lower leaf surface. Once pod set begins on soybean, infection can spread rapidly to the middle and upper leaves of the plant.
What Can Producers Do?
To assist producers in the defense against the spread of soybean rust, MDA offers the following suggestions:
- Educate yourself on the disease. Learn to distinguish between soybean
rust and other soybean foliage diseases that are already present in Missouri.
- Know your fields. Surveying and scouting of land is important to early
detection of the disease.
- Question irregular growth patterns. The University of Missouri Extension
Soil Testing and Plant Diagnostic Services tests soybean tissue to determine
the presence of soybean rust. For more information on submitting samples,
visit http://soilplantlab.missouri.edu/plant/ or call (573) 882-3019.
- Budget for the extra cost of fungicides. USDA estimates a cost increase of 15% (or approximately $25 per acre) to apply fungicides.
To Learn More, Contact:
- Missouri Department of Agriculture’s Plant Industries Division
at (573) 751-2462.
- For the most up to date soybean rust reports, visit http://sbr.ipmpipe.org/cgi-bin/sbr/public.cgi.
- University of Missouri Extension soybean rust website has a guide sheet, information
on crop budgets, sample submission, and fungicides labeled, plus links to efficacy
trials and USDA soybean rust sites at http://agebb.missouri.edu/mgt/soyrust/.
- Missouri Soybean Association by visiting www.mosoy.org.
- USDA-APHIS by visiting www.aphis.usda.gov or call the USDA Industry Hotline at (888) 703-4457.
- Additional materials can be found at:
http://www.aphis.usda.gov/plant_health/
http://www.aphis.usda.gov/lpa/pubs/fsheet_faq_notice/faq_phsoybeanrust.html
http://www.ers.usda.gov/Features/SoyBeanRust/
USDA Photos:
Figure 1--Typical foliar symptoms of soybean rust
Figure 2--Pustules on under surface of soybean leaf