Plant Pathologist Mohammad Babadoost told Brownfield that the fungal disease bitter rot was prominent in central and southern Illinois in the last two years. “Some orchards in 2017 had almost 100% losses.”
He says since there is no resistance to bitter rot, white rot, or black rot, fungicides and cultural controls are the only management options. “Apples do not completely disintegrate. They become mummies and carry the pathogen from one year to another year. Collecting all of the dead woods and mummies and then burning them or burying them is essential.”
He says they are also working with effective fungicides that are less harmful to applicators and the environment. Babadoost says he plans to apply the management practices in commercial orchards next year. Bitter rot is a fungal disease that effects apples in late summer. Honey Crisp, Empire and Gala varieties are especially susceptible.