Envirologix: Putting Science to the Test

Soybean Rust Strips

A Little History

First found in Japan in 1902, Asian soybean rust, caused by Phakopsora pachyrhizi, passed through Africa and South America before infiltrating Louisiana in 2004. Soybean rust is a devastating fungal disease, spread primarily by windborne spores that can be transported over long distances.

In 2006, rust in the US reached as far north as Illinois and Indiana, and was detected in Missouri to the west and Virginia to the east. By the end of the year, twice as many counties in twice as many states reported rust as 2005. The first rust of 2007 was found in January, over-wintering on kudzu in several southern states.




Effects on Crop Yield

Soybean rust (SBR) causes early leaf drop, inhibiting pod set and reducing crop yield. The disease can develop rapidly in a soybean field, both in incidence and severity. Southeastern states have reported significant yield losses while growing regions in other parts of the world have seen yield losses up to 80 percent.




SBR Management

Despite its destructive potential, soybean rust can be managed. While scouting production fields at regular intervals, producers are also encouraged to monitor reports from sentinel plot networks, disease forecasting models, and independent detections in the local area. This set of information can facilitate important crop management decisions, including whether and when to apply “preventive” or “curative” fungicide. The extent of disease progression in a field and the stage of plant growth also affects the economics of fungicide decisions.




Early Detection

Effective rust management requires that the disease be detected early. The short life cycle of the soybean rust fungus increases the likelihood of many generations being produced within a brief period of time. This creates a short window of opportunity to put control measures in place.

When used with existing management approaches, the QuickStix kit provides early, accurate and timely field detection of SBR. Combined with scouting, confirmation and advice from crop-management experts, the QuickStix kit is a tool to assist in the timing and application of fungicide applications.



Specific Identification

One of the challenges of identifying rust in the early stage is that symptoms of the disease can look like other soybean foliar diseases. Based on testing done to date, the QuickStix test is specific to Asian Soybean Rust, ruling out infection by other soybean leaf diseases like Septoria Brown Spot, Bacterial Pustule, Bacterial Blight, Downy Mildew, Frogeye Leaf Spot, and Cercospora Leaf Blight.




Risk Assessment

In addition to using the QuickStix test, use other information available to evaluate risk and determine if and when it’s necessary to act.

• Know when there is a severe SBR attack within
  100 miles of the field



• Evaluate the climatic conditions: more than 6 hours of dew and moderate temperatures, 68-77°F (20-25°C) are optimal conditions for rust growth



• Growth stage of the plants: Plants are most susceptible between the end of the vegetative stage thru R5/R6, about 35-50 days

The QuickStix Test is Fast and Easy to Use

The QuickStix test can be performed in a few easy steps and takes about 10 minutes to complete. Designed for field use; no need for laboratory equipment or special training.

Click here for the QuickGuide for step-by-step instructions.

When combined with established SBR monitoring and management practices, the QuickStix test provides critical information for profitable crop-management decisions. Growers, crop consultants, fungicide experts or other specialists can now have more information to make chemical control decisions.

Catalog number AS107
Kit sizes are 25 tests for $110 or 50 tests for $200. Everything you need is included.

Also available is the QualiPlate™ ELISA test kit; the first microwell test for soybean rust. This highly sensitive test has been used in diagnostic laboratories since 2004. Catalog number AP107




Click here for a list of links to helpful websites relating to Soybean Rust.

More questions? See our FAQ page or email us using the button below.

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