What is Corn Stunt Disease, and Could it Appear in Michigan?

You may not have heard about Corn Stunt Disease, but it’s causing damage to corn this year in Argentina and dropping corn yields there by 10-to-15 percent.

“Corn stunt disease is a disease that is caused by a Spiroplasma that is actually transmitted by leafhoppers in the field,” according to Dr. Darcy Telenko, Associate Professor of Plant Pathology at Purdue University.

“Here in the United States, we have detected the disease, but it’s been a minor issue,” she says. “It’s mainly been found in the southern part of the United States—in Southern Florida and Texas—and I know they’re having major issues in Argentina, but here in the United States, it’s been around for a while. I have reports that they found it in California in 1996 and they continue to find it, but generally, we don’t think it’s leading to significant losses here in the United States.”

So far, she says, two things are absent in Michigan that would lead to the spread of Corn Stunt Disease.

“The inoculum has to be present for the corn leafhopper to pick it up, and then you have to have populations of the corn leafhopper with the disease that would spread it through the crop canopy,” she says.

Overall, Dr. Telenko says she’s not worried about Corn Stunt Disease impacting corn yields in the Midwest.

“Generally, we don’t see many viral diseases here in United States causing losses to corn, so I would say it’s not really a disease problem I’m worried about seeing,” says Telenko. “I would keep an eye out if I start hearing more reports out of Texas or Florida where they might start seeing a little bit more infections since it’s already been documented there and they’ve seen in California.

“We’ll monitor that and we’ll keep an ear out with my counterparts that are in those states if they start seeing a problem with it. I’m hoping it’s not a disease that we’re going to have to worry about,” she says.

The Buenos Aires Grain Exchange has lowered Argentina’s corn production estimates this year by two million tons due to recent impact of the disease.