The tool farmers have used for two decades to control the corn rootworm is beginning to fail. Entomologists from the University of Illinois will host a webinar Thursday, March 30 at 11am central to discussion the issue. Nick Seiter, Extension Field Crops Entomologist will lead that discussion.
“So, the situation with corn rootworm right now is really interesting and depends quite a bit on where you are in the state. If you are in east central Illinois, you are probably not thinking about corn rootworm. We have low populations compared to what they’ve been historically in particular when we look at the rotation resistant variant western corn rootworm. Our populations in soybean in east central Illinois are very low and we are not seeing issues from that insect in first year corn. Now, when you go north of Interstate 80 and you get into country where we have a lot more corn-after-corn production, it is a very different story. Particularly in DeKalb, Kane, Stephenson, Ogle, and Lee counties. We’ve seen an increase in corn rootworm problems over the last few years. Most concerning, we’ve seen unexpected damage to our pyramided Bt traits. This is very tightly associated with areas of continuous corn and especially longterm continuous corn. The other thing that has been changing is that the populations where Bt traits have been damaged include not just the western corn rootworm. We are seeing a pretty healthy dose of the northern corn rootworm, too. In fact, in most of our problem fields we see a mix of those two populations or even in some cases more northerns than westerns. This something very different than what we were seeing five, ten, to fifteen years ago.”
In response Seiter and his entomology colleague on campus at the University of Illinois, Joe Spencer, are hosting a webinar for farmers and others interested in the rootworm, building Bt resistance in northern Illinois, and how to manage the issues.
“So, we are going to really try in this webinar to cover the basics of what we think a farmer or consulting needs to know about corn rootworm for the 2023 growing season. This will include some background on the insects biology and basic management, but especially we’ll talk a lot about Bt resistance status in our western and northern corn rootworm populations. We’ll explore how the situation differs throughout the state both in terms of resistance and in general rootworm abundance. Finally, we’ll offer some things farmers can do in terms of management of this pest. So, what you want to know as a farmer about what’s going in your field with corn rootworm and what you can do about it. That’s what we are trying to get at with this webinar.”
The “Corn Rootworm: Bt Resistance and Management Recommendations for Illinois” webinar is scheduled for 11am Thursday, March 30 visit farmdoc Daily to sign up for free. Look under webinars and upcoming at farmdocdaily.illinois.edu. Registration is free.
***Courtesy of Todd Gleason***
