FIGURE 4: Quantification of chromatin condensation in hyphae of B. cinerea wild type and BcBIR1 strains.

Fungi were grown for 24 h in PDB medium at 22°C after which H₂O₂ was added to a final concentration of 10 mM. The cultures were incubated for additional 4 h, samples were removed, stained with Hoechst 33342 and then visualized at 1000x magnification. The percent of nuclei with condensed chromatin was scored and calculated manually (white bars), or by the Condensation module of the SCAN^© software (black bars). Data are the mean average ± SEM of three samples, each containing at least 200 nuclei (n = 3). Percentage of apoptotic nuclei in untreated cultures was lower than 15% (not shown). Columns and lines not connected with the same letter are statistically different according to two-way ANOVA (P < 0.05) followed by a post-hoc Tukey HSD analysis (P < 0.001).