There is not much soybean disease or insect pressure this year in central Iowa according to Iowa State University Field Agronomist Mark Johnson, “We’ve seen a little bit of [Sudden Death Syndrome], not a lot, we’ve seen a little bit of Brown Stem Rot, not a lot.”
Sudden Death Syndrome (SDS) and Brown stem rot are two common diseases in Iowa, Johnson says there are others that are more prevalent.
“The primary diseases we’ve seen this year with frequency is Septoria brown spot, which is the spots on the lower canopy. We don’t really do much about that because it is the lower canopy and pretty soon, those aren’t catching much sunlight for photosynthesis anyway. And the other one we saw quite a bit of this year earlier was bacterial blight on the leaves and that’s usually on the upper canopy.” He says, “And you can’t do anything about that because that’s bacterial. Fungicide won’t touch it.”
Iowa State University Extension says bacterial blight is spread by wind and rain. They say it occurs every year but does not cause significant yield losses.