Fig. 1.

T-DNA insertion mutant vir-88 is impaired in virulence and conidiation. A. thaliana Col-0 plants were infected with C. higginsianum WT and the vir-88 mutant strain. a Macroscopic image at 4 dpi. b Microscopic images of germinated conidia with appressoria at 1 dpi on trypan blue stained leaves. Appressoria with unusual morphology are marked with white arrows. c Trypan blue stained A. thaliana leaves at 3 dpi. d Quantification of trypan blue stained primary hyphae (relative to appressoria) and secondary hyphae (relative to primary hyphae) at 3 dpi. e Appressoria of WT and vir-88 on artificial hydrophobic surface. Appressoria with unusual morphology are marked with arrows. Scale bars = 20 μm. f Vegetative growth of WT and vir-88 on oatmeal agar (OMA), potato dextrose agar (PDA) and Czapek-Dox minimal medium (MM). g, h Average conidial cell volume g and conidial titer h of WT and vir-88 strains recovered from oatmeal agar after 7 days. The data of 3 separate plates is given. Error bars are represented as the standard error from three replicates. Significant differences based on t-tests (p < 0.05) are marked with asterisks