Brazil Experience Will Aid in Asian Soybean Rust Identification

March 30th, 2005

Seeing Asian soybean rust first-hand may aid in its identification this growing season. In February, eight Iowa State University crop specialists and six members of the Iowa Soybean Rust Team took a trip to Brazil to observe soybean rust in the field and learn to better identify the disease.

"My goal was to get down there and get a hands-on diagnosis of soybean rust, so I can confidently identify the disease if it shows up here," said Joel DeJong, Iowa State Extension field specialist in LeMars. "We also learned how they managed rust, which will be helpful this growing season."

DeJong is a triage person in the Fast Track identification system set up by the Iowa Soybean Rust Team. The system was developed to quickly identify soybean rust in Iowa and efficiently manage samples submitted to the Iowa State University Plant Disease Clinic.

The Fast Track system is simple. Producers submit samples to first detectors at no cost. First detectors send suspect samples to triage personnel for further diagnosis. The triage person then forwards suspect samples to the Plant Disease Clinic. The triage personnel include Iowa State Extension specialists throughout the state.

Palle Pedersen, Iowa State soybean extension agronomist, led the 10-day tour through Brazil's soybean regions. Pedersen said the trip was useful because the group visited several types of farms and had the chance to view the disease in several stages.

"Asian soybean rust has only been in Brazil since 2001 and the Brazilian farmers have learned to manage it and they don't see it as a threat," Pedersen said. "It has to do with timing, knowledge about the disease and efficiently managing it."

The group visited 10 farms ranging in size from 150 to 55,500 acres. Pedersen said every field but one they visited was infected with soybean rust.

"The environmental conditions are so different down there and soybean rust is very damaging if it is not managed in Brazil," Pedersen said. "It rains nearly every day in the central part of Brazil and the temperature is between 75 and 95 degrees Fahrenheit every day."

DeJong said he learned some practical information that he also can use in applicator training sessions.

"I hope to include this information in my presentations," DeJong said. "It will be incorporated into a lot of our discussions because almost everything we're talking about includes soybean rust."

More information about Asian soybean rust can be found at:


Palle Pedersen, Agronomy, (515) 294-9905,
Joel DeJong, Extension, (712) 546-7835, jldejong@iastate
Barbara McBreen, Communications Service, (515) 294-0707,