Thermal and Oxidative Tolerance Assay

The amount of glucose liberated by the activity of trehalase was measured using a glucose assay kit (Sigma) and converted into the trehalose amount per conidium (23). Each sample not treated with trehalase served as a negative control. The experiments were performed in triplicate. To examine thermal tolerance, WT (FGSC26) and mutant (RNI10.2) conidia were incubated at 50°C for 0, 5, 20, 30, 45 or 60 min. To examine oxidative tolerance, WT or mutant conidia were treated with varying concentrations (0, 0.25, 0.5, 0.75 or 1 M) of H₂O₂ and incubated for 30 min at room temperature [45] (link). In both cases, the spores were inoculated on solid MM and incubated at 37°C for 48 h. Colony numbers were counted and calculated as a percentage of the untreated control.