Moldy corn and soybean issues
Damon L. Smith, Extension Field Crop Pathologist
Department of Plant Pathology
UW-Madison College of Agricultural and Life Sciences
FOR MORE INFORMATION:
3:01 – Total Time
0:17 – Corn & soybeans being hit
0:47 – Found statewide
1:50 – Threat of toxins, lower quality
2:43 – For more information
2:51 – Lead out
Sevie Kenyon: We’re look at some moldy corn and soybeans. We’re visiting today with Damon Smith Department of Plant Pathology University of Wisconsin-Madison/Extension in the College of Agricultural and Life Sciences and I’m Sevie Kenyon. Damon, can you give us a quick snap shot of what’s going on with our corn and soybeans?
Damon Smith: Yeah, we’ve got a lot of corn around the state that’s either had stalk rot or ear rot issues or in a lot of cases, both. We’ve actually seen some corn go down already this year because of stalk rot issues and now we’re delayed harvest and so we’re going to have a lot of ear rot issues in there. So, in soybeans we’re seeing a particular rot, phomopsis seed decay, really only one issue in soybeans but it can be significant if we can’t get in these fields pretty soon.
Sevie Kenyon: Damon how wide spread are these issues?
Damon Smith: Pretty wide spread across the whole state. It does vary pretty much where you are in the state in terms of the actual incidence within a field. Usually in the fields that we’ve seen more wet weather those are going to be the ones harder hit. So, west side of the state is going to probably be worse than the east side where we’ve seen a lot of rain.
Sevie Kenyon: Damon what does this look like in the field?
Damon Smith: In corn we have three different ear rot diseases so we’ve got fusarium, giberrella, and diplodia are the three significant ear rots there. Basically, if a grower wants to find out whether they have and ear rot problem they should choose 5 locations in that field take 10 ears out of those 5 locations pull those ears back and look for white moldy growth on those ears. If they see something they can certainly send it in to our diagnostic clinic for a diagnosis for sure, and soybeans they’re going to want to do a similar thing, kind of scout out multiple locations in the field, crack some pods open and see how bad the decay issue is there.
Sevie Kenyon: What are the effects of these molds in the various crops?
Damon Smith: So, in corn you know that we really worry about secondary metabolites, what we call mycotoxin accumulation so fusarium and giberrella fungi produce these mycotoxins. Fortunately, with diploida the third group of organisms that are causing ear rots we don’t have that mycotoxin issue with that particular organism, but it does cause reduced quality. Of course, with a mycotoxins we’re worried about feeding that to animals or that mycotoxin contaminated grain making it into the human food supply. With soybeans we don’t have any mycotoxin issues but we have seed rot associated with phomopsis seed decay we’re going to see really low seed quality coming out of fields having high levels of phomopsis seed decay. We’re going to see lighter grain, lower yields in those fields for sure.
Sevie Kenyon: And Damon, where should people go if they need more information?
Damon Smith: They just simply google “Wisconsin field crop pathology” and we have some resources on that website for both corn, grain, and also soybean.
Sevie Kenyon: We’ve been visiting with Damon Smith Department of Plant Pathology University of Wisconsin-Madison/Extension in the College of Agricultural and Life Sciences and I’m Sevie Kenyon.