[1] WSL Swiss Fed Res Inst, CH-8903 Birmensdorf, Switzerland
[2] Univ Marburg, Fachbereich Biol, D-35032 Marburg, Germany
[3] INRA Pierroton, Biodivers Genes & Communities UMR1202, F-33612 Cestas, France
[4] Wageningen UR, ALTERRA Ctr Ecosyst Studies, NL-6700 AA Wageningen, Netherlands
[5] INRA Nancy, UMR Interact Arbres Microorganismes, F-54280 Champenoux, France
[6] Helmholtz Zentrum Munchen, Inst Soil Ecol, D-85764 Neuherberg, Germany
[7] Johann Heinrich von Thuenen Inst, Inst Forest Genet, D-22927 Grosshansdorf, Germany
[8] Wageningen UR, Plant Res Int, NL-6700 AA Wageningen, Netherlands