Phomopsis, a stalk disease that hits sunflowers first showed up in South Dakota last fall. National Sunflower Association Executive Director John Sandbakken says the stem canker occurs during periods of excessively wet weather and during times of high humidity.
Sandbakken say it’s tough to deal with since there are no registered fungicide treatments available for the disease. He says they’re currently researching the problem and looking for possible solutions.
He says phomopsis is most prevalent in Europe but has been seen in both Dakotas and other areas of the country where there’s been high humidity and excessive moisture.