Despite the fact that the phyllosphere can support dense populations of microbes, we are only beginning to understand the interactions that occur between multiple plant pathogens during infection. The widespread occurrence of Potato virus Y (PVY, Potyviridae) in potato leads to a strong likelihood that plants infected with the virus will encounter other pathogens during the growing season. Phytophthora infestans and Alternaria solani, which cause potato late blight and early blight, respectively, are widespread within U.S. potato growing regions and currently resistance in commercial potato varieties is limited. Our preliminary data has revealed a three-way interaction between PVY, its potato host and the mycelial pathogens. This interaction includes altered plant defense responses, a reduction in fungal pathogenicity, and a potentially novel vector transmission strategy.