Red Crown Rot Showing Up in Indiana Soybean Fields

Red crown rot in soybeans has been far more common in southern states, but its appearance in the Midwest is still a relatively recent development, having been detected in Indiana for the first time in 2022.

“This is a warning for everybody across the state,” says Darcy Telenko, Purdue Field Crop Pathologist, “that where you think you might have sudden death syndrome, SDS, in your field, I want you to check it this season. Because it may not be SDS, or it may not only be SDS. It might be red crown rot, and we’re trying to document that in the state.”

Telenko says red crown rot is difficult to diagnose because the symptoms are nearly identical to other diseases like sudden death syndrome and brown stem rot. She shared this conversation with Purdue Extension’s ‘Soybean Shaun’ Casteel on the latest Purdue Crop Chat podcast.

“The problem is they all turn and have similar foliar symptoms as we reach the reproductive stages. We have some of our plots where we’ve targeted SDS and inoculated. We’ve seen some of the bright yellow flecking occur already early. So, initially, some of those leaves may have yellow flecking and then eventually those lesions are going to coalesce, and you have leaf veins that are green and then brown, dead tissue between”

Telenko says there’s nothing that can be done now to mitigate red crown rot this season, but you need to know if it’s there.

“You have to know to figure out where we’re going, how we’re going to manage it going forward. If we’re looking at making variety selections or maybe even seed treatments to try to protect that, but those are things you need to do beforehand. We can’t do anything now.”

As of Thursday afternoon, red crown rot had been detected in 8 Indiana counties: DeKalb, Allen, Adams, Rush, Decatur, Bartholomew, Knox, and Spencer. Hear more from Telenko in the Purdue Crop Chat below or wherever you listen to podcasts.