1. School of Natural Sciences Technology and Environmental Studies, Södertörn University, Alfred Nobels allé 7, SE‐14189 Huddinge Stockholm Sweden
2. Department of Forest Mycology and Plant Pathology Swedish University of Agricultural Sciences, SE‐75651 Uppsala Sweden
3. Leibniz Institute for Baltic Sea Research Warnemünde Seestraße 15, DE‐18119 Rostock Germany