Broad-spectrum fungicides are the primary products used for the management of Alternaria. However, a shift to include narrow-spectrum fungicides in rotation was made in order to minimize the impacts on mammal toxicity and alleviate environmental concerns due to chemical residues.
Fungicide resistance must be taken into account when the chemical affects a single site and is repeatedly used. The latest “Focus on Potato” presentation by Washington State University’s Lydia Tymons, which can be viewed here, provides consultants and growers with the best practices to manage early blight on potato. It will review fungicide basics, exhibit how quickly fungicide resistance develops, and briefly compare pathogenicity and aggressiveness of the early blight pathogen, A. solani, to the brown spot pathogen, A. alternata, and review best management tactics for early blight.