After another year with very little threat from soybean rust, is this disease, much feared when it first arrived in the country, as big a threat to U.S. soybean production as it was first thought? The answer is complicated. Extension specialists don’t want farmers to let their guards down.

Perhaps the only good news to come out of the drought of 2011 for the southern states was the fact that it did not foster the growth of soybean rust spores. Without significant rain or a tropical storm or hurricane to blow spores deep into the Midwest, soybean rust, remained a non-factor for farmers.

Despite the lack of soybean rust spores this year, plant pathologists, especially in southern states, continue to monitor for soybean rust.

“In Iowa, we have had an agreement with the Iowa State University Research and Demonstration Farms to establish a sentinel plot system when the threat of soybean rust materialized,” said Daren Mueller, Extension specialist, Iowa State University. “We never did start scouting at the ISU research farms in 2011. While soybean rust has petered out the past two seasons, this only exemplifies the importance of an established nationwide scouting system. Knowing that soybean rust is not on the move allows Midwestern growers the peace of mind to mentally eliminate this disease as a possible threat each particular year and concentrate on other issues. Soybean rust will need to reestablish itself on kudzu in southern states before it is even a threat to the South. Until then, soybean growers in Iowa can focus on other things.”

So, as long as the drought continues in the South, the threat of soybean rust for the foreseeable future remains dim. However, plant pathologists don’t want farmers totally ignoring the disease. It still poses a threat if all of the right ingredients come together.