DES MOINES, Iowa – Yield-wise, this year’s Iowa soybean crop probably won’t be breaking any statewide average records. Iowa State University Field Agronomist Mark Johnson works in the fields of ten central Iowa counties, and says many beans in his area weren’t planted until June. He says in some places the stand is still just knee high. Other fields were planted earlier and in better conditions. But even there, Johnson says he’s seeing some localized disease pressure, like Sudden Death Syndrome (SDS).
Johnson explains how SDS affects the plant, “When an area turns yellow, that’s called chlorotic. And then when it turns brown, that’s necrotic. So, necrotic means it’s dying or dead. So what happens with Sudden Death Syndrome is it gets infected in the roots very, very early, so it typically shows up more in beans that were planted in early, cool, wet soils. And then it just kind of sits there until you get a lot of demand on the plant trying to fill the pods. Once you see it it does really go through the symptoms pretty quickly.”
SDS is one of the top yield robbing diseases in soybeans. The Iowa State University Extension says from 1999 to 2004 average losses in the U.S. were estimated at $190 million a year.
Overall, Johnson says disease and insect pressure has been low in his counties this year.