Fig. 3.

The N-terminus of BcNoxA is essential for full functionality. The deletion mutant of bcnoxA was complemented by bcnoxA or a N-terminal truncated version of bcnoxA. The construct was integrated into the bcniiA locus (Additional file 1: Table S1). A, B The truncated bcnoxA version is not able to infect bean leaves as the wild type. Bean leaves were inoculated with agar plugs. Lesion diameters were measured and statistically evaluated. Replicates showed similar results. C ΔbcnoxA:bcnoxA w/o SP is able to produce hyphal fusions. Conidia were incubated on minimal medium for 18 h. Hyphal fusions were detected microscopically and evaluated statistically (300 spores each). D ΔbcnoxA:bcnoxA produces wild type like amounts of conidiospores. The strains were incubated on CM medium for at least 3 weeks. Conidia were harvested, diluted and counted. Replicates showed similar results. E Tests for stress sensitivity reveal that ΔbcnoxA:bcnoxA w/o SP is equally sensitive to oxidative stress such as H₂O₂ (10 mM) or menadione (500 µM) as the deletion mutant of bcnoxA. Agar plugs were set on CM and selective media and monitored for seven days (here depicted: 3 dpi). F Sclerotia production is restored in the strain ΔbcnoxA:bcnoxA w/o SP. Agar plugs were incubated on CM in constant darkness for at least 14 days. G BcNoxA w/o SP-GFP has a different localization pattern compared to BcNoxA-GFP. Conidia were incubated overnight on microscopic slides and analyzed microscopically. The untruncated version can be found in the nuclear envelop (a), while the truncated version is located in filamentous structures (b) as well as in the region of septa (c). H ΔbcnoxA:bcnoxA w/o SP is still impaired in the production of infection cushions. Onion epidermal layers were incubated with agar plugs for at least 20 h. Just before microscopy the fungal material on the surface of the epidermal layers was stained with lactophenol blue. Scale bars 10 µm