Careful Scouting is First Line of Defense

Growers throughout the United States should be on the lookout for any symptom of soybean rust in their fields this season.

Early detection may be a double-edged sword. On one hand, early detection is essential to provide adequate protection. But on the other hand, soybean rust is difficult to identify, and a misdiagnosis could lead to widespread confusion and unnecessary fungicide applications.

The USDA recommends following these procedures to confirm the presence of soybean rust in a field:

• Collect samples immediately if soybean rust is suspected on soybeans or other host plants.
  
  
• Place samples in self-locking plastic bags.
  
  
• Keep samples refrigerated or seal them in paper bags if refrigeration is not available.
  
  
• Keep leaves flat by placing them between paper towels or pieces of paper.
  
  
• For each sample, record the collection date, collector's name and phone number, field location (including state, county township, nearest intersection and GPS coordinates, if available).
  
  
• Mark samples with a permanent marker, and print all information.
  

Growers should send plant samples to their state university's plant disease diagnostic lab or state department of agriculture's lab.

If the sample cannot be diagnosed as a disease other than soybean rust, it will be forwarded to a USDA/APHIS national mycologist in Beltsville, Md., for further research.

Early detection, followed by proper diagnosis, will be the starting point for effective control. Identification of the disease by USDA-APHIS is the mandatory first step towards getting approval of fungicides listed on the Section 18 lists.