The wet spring this year has led to some Phytophthora root and stem rot in Wisconsin soybeans this year. University of Wisconsin Field Crops Pathologist Damon Smith says samples taken from June 6th to July 16th found the pathogen in soybean fields in 15 counties. That does not mean the disease will flourish but he says they have been getting positive samples in the diagnostic lab. “We’re seeing more of the stem rot this year.”
Given the moderate weather, Smith thinks most of the infection has already occurred and damage will be limited. On top of that, most of the soybeans planted in the state are Phytophthora-resistant although there is a difference between resistance and immunity.
He says producers should monitor their fields, if they suspect a problem take a sample and get it analyzed to make sure it is Phytophthora. It is important to keep accurate records for future reference as any infection should be taken into consideration when making planting choices next year.