The Effect of Winter Applications of Azoxystrobin on Dollar Spot Incidence During the Following Summer
Heritage® is composed of 50% azoxystrobin and has been shown as extremely effective as a broad-spectrum activity against oomycetes, as well as ascomycetes and basidiomycetes. It is not effective against dollar spot disease, which is caused by Sclerotinia homoeocarpa. There is little experimental evidence but reports have been made that increase in dollar spot has been seen after treatments with azoxystrobin. The field test conducted in 2001-2002 and 2003-2004 documented an increase in dollar spot incidence eight months after a single application for snow mold control. Results from these studies show significantly higher levels of dollar spot disease on the plots treated with azoxystrobin in comparison to plots that were not treated with any fungicide or those treated with other fungicides.