Fig. 1.

Transcriptional regulation seems to be not important for NoxA function. Three complementation constructs (C1–C3) were generated and transformed in ΔbcnoxA. They were integrated into the bcniiA locus (Additional file 1: Table S1). a, b Wild type like spore-mediated infection is restored in ΔbcnoxA:C1 and ΔbcnoxA:C2. Primary bean leaves were infected with 7.5 µl of conidial suspension (10⁵ conidia/ml). Lesion diameters were measured and statistically evaluated (3 bean plants/strain). Replicates showed similar results. c Only the mutant strain with the construct C2 is able to fully restore the formation of CATs. Conidia were inoculated on Vogel’s minimal medium for at least 18 h. Hyphal fusions were detected microscopically. For statistic evaluation, 300 spores were analyzed. d Restoration of wild type like sclerotia formation is mediated by the C2 construct. Agar plugs were inoculated on complete medium in constant darkness for at least 14 days. Replicates showed similar results. e Only ΔbcnoxA:C2 produces the same amount of conidiospores as the wild type. Spores were harvested from CM plates with 10 ml H₂O and quantified in replicates. f Plate assays for the determination of the stress sensitivity display identical results for the wild type and the strain ΔbcnoxA:C2. Agar plugs were placed on CM agar and medium supplemented with H₂O₂ (10 mM) or menadione (500 µM). Monitoring was accomplished for 7 days (here depicted: 3 dpi). g Infection cushion formation is restored in the strains ΔbcnoxA:C1 and ΔbcnoxA:C2. Onion epidermal layers were inoculated with agar plugs of the respective strains. Staining of fungal hyphae was performed with lactophenol blue just before microscopy