Growth and Pathogenicity Assays

For characterization of the different mutant strains various growth, differentiation and pathogenicity assays were performed. For testing defects in pathogenicity, French bean plants (Phaseolus vulgaris L.) were infected according to Klimpel et al. (2002) with agar plugs or conidia from freshly sporulated PDAB plates. Germination on glass surfaces was tested as described by Doehlemann et al. (2006). Penetration ability was checked on onion epidermal layers after inoculation with washed conidia. Before microscopy, the hyphae growing on top of the layers were stained with lactophenol blue. For observation of ICs, the epidermal layers were inoculated with agar plugs of mycelium and incubated overnight (Siegmund et al., 2015). For visualization of CATs media and strains were prepared following Siegmund et al. (2015).