Effect of a combined application of catalase and respectively prothioconazole + fluoxastrobin (a) and prothioconazole (b) on extracellular H
concentrations at 4 h after fungicide application. Conidia at a concentration of 106 conidia/ml were challenged with a tenfold dilution series of fluoxastrobin + prothioconazole, azoxystrobin and prothioconazole starting from 0.5 g/l + 0.5 g/l, 0.83 g and 0.67 g/l in the absence (dashed line) or presence of 1000 U/ml catalase (solid line). H2O2 was measured at 4 h using TMB (trimethylbenzidine) as a substrate in the presence of an overdose of peroxidase. The H2O2 concentrations were calculated based on a standard curve included in each experiment. Each data point is the result of three repetitions and the experiments were repeated twice in time. Different letters at each data point indicate differences from the control treatment after analysis with a Kruskall-Wallis and Mann-Whitney test with a sequential Bonferroni correction for multiple comparisons.