1. Botanical Institute; Cologne Biocenter; Cluster of Excellence on Plant Sciences (CEPLAS); University of Cologne; Cologne 50674 Germany
2. Department of Biology; Friedrich Alexander University Erlangen-Nürnberg; Erlangen 91058 Germany
3. Metanomics GmbH; Berlin 10589 Germany
4. Max-Planck Institute for Molecular Plant Physiology; Potsdam-Golm 14476 Germany
5. Leibniz Institute of Plant Genetics and Crop Plant Research (IPK); Stadt Seeland, OT Gatersleben 06466 Germany