PPSFamily Lamiaceae is one of the largest plant families with a cosmopolitan distribution comprising more than 6 000 species in 236 genera described worldwide (Carović-Stanko et al. 2016). Representatives of this family are annual, biennial and perennial typical herbs (Carović-Stanko et al. 2016). However, some species are shrubs, trees, or vines, but in the Czech Republic, they are occurring as herbs or semi-shrubs (Slavík 2000). Many family members are widely cultivated for their aromatic qualities (Capecka et al. 2005) and ease of cultivation and use in decoration .Powdery mildews (Erysiphales, Ascomycota) are obligate biotrophic parasites of vascular plants, appearing as a white layer on the green parts of the plant and acting as a debilitating agent on the host (Braun & Cook 2012). Worldwide, up to 11 powdery mildew species in five genera have been described in the family Lamiaceae, namely Erysiphe, Golovinomyces, Leveillula, Neoërysiphe and Podosphaera. However, only three powdery mildew species have been confirmed in the Czech Republic: Golovinomyce orontii, G. biocellatus and Neoërysiphe galeopsidis (Braun & Cook 2012).