1. Molecular Ecology, Agroscope, Zurich, Switzerland
2. Research Centre for Agriculture and Forestry Laimburg, Auer, Italy
3. Institute of Microbiology, Leopold-Franzens University Innsbruck, Innsbruck, Austria
4. Sustainable Agroecosystems, Institute of Agricultural Sciences, ETH Zürich, Zurich, Switzerland
5. Plant Ecological Genetics, Institute of Integrative Biology, ETH Zürich, Zurich, Switzerland