15 Biotechnology Research Center, School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA 16 Department of Cell and Systems Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, M5S 3B2 Canada 17 School of Forest Resources and Huck Institutes of the Life Sciences the Pennsylvania State University, University Park, PA 16802, USA. Department of Biology, Institute of Molecular Evolutionary Genetics, and Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA 19 Architecture et Fonction des Macromolecules Biologiques, UMR6098, CNRS and Universities of Aix-Marseille I and l, case 932, 163 avenue de Luminy, 13288 Marseille France 20 Warnell School of Forest Resources, University of Georgia, Athens, GA 30602, USA 21 Department of Plant Biology, University of Georgia, Athens, GA 30602, USA 22 School of forest Resources and Conservation Genetics Institute. and Plant molecular and Cellular Biology Program, University of Florida, Gainesville, FL 32611, USA. INRA-Orleans, Unit of Forest Improvement, Genetics and Physiology, 45166 Olivet 24 Center for Integrative Genomics, University of California, Berkeley, CA 94720, USA. 25 Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. 26 Department of Plant Sciences, University of Arizona, Tucson, AZ 85721, USA. 27 Department of Biological Sciences, Purdue University, West Laf ayette, IN 47907, USA. 8 The Stanford Human Genome Center and the Department of Genetics, Stanford University School of Medicine, Palo Alto, CA 94305, USA. 29 Institute of Forest Genetics, United States Department of Agriculture, Forest Service, Davis. CA 95616 USA. 30 Federal Research Centre for Forests, Hauptstrasse 7, A-1140 Vienna, Austria 31 Plant Molecular Biology Laboratory, Institute of Biotechnology, University of Helsinki F1-00014 Helsinki Finland 32 Department of Biological and Environmental Sciences, University of Helsinki, FI-00014 Helsinki Finland 33 Department of Biology, 200014, University of Turku, F1-20014 Turku, Finland Southern Institute of Forest Genetics, United States Department of Agriculture, Forest Service and Department of Forest Science, Texas A&M University, College Station, TX 77843.UsA 35 Whitehead Institute for Biomedical Research and Department of biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA 36 Department of Molecular Sciences and Center of Excellence in Genomics and Bioinformatics, University of Tennessee, Memphis, TN 38163, USA. 37 Southern Institute of Forest Genetics, United States Department of Agriculture, Forest Service. Saucier. MS 39574 USA. Developmental Genetics, University of Tubingen, D-72076 Tubingen, Germany 39 Department of Biotechnology, KTH, AlbaNova University Center, SE-106 91 Stockholm These authors contributed equally to this work as second authors15 Biotechnology Research Center, School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA. 16 Department of Cell and Systems Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, M5S 3B2 Canada. 17 School of Forest Resources and Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA. 18 Department of Biology, Institute of Molecular Evolutionary Genetics, and Huck Institutes of Life Sciences, The Pennsylvania State University, University Park, PA 16802, USA. 19 Architecture et Fonction des Macromolécules Biologiques, UMR6098, CNRS and Universities of Aix-Marseille I and II, case 932, 163 avenue de Luminy, 13288 Marseille, France. 20 Warnell School of Forest Resources, University of Georgia, Athens, GA 30602, USA. 21 Department of Plant Biology, University of Georgia, Athens, GA 30602, USA. 22 School of Forest Resources and Conservation, Genetics Institute, and Plant Molecular and Cellular Biology Program, University of Florida, Gainesville, FL 32611, USA. 23 INRA-Orléans, Unit of Forest Improvement, Genetics and Physiology, 45166 Olivet Cedex, France. 24 Center for Integrative Genomics, University of California, Berkeley, CA 94720, USA. 25 Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. 26 Department of Plant Sciences, University of Arizona, Tucson, AZ 85721, USA. 27 Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA. 28 The Stanford Human Genome Center and the Department of Genetics, Stanford University School of Medicine, Palo Alto, CA 94305, USA. 29 Institute of Forest Genetics, United States Department of Agriculture, Forest Service, Davis, CA 95616, USA. 30 Federal Research Centre for Forests, Hauptstrasse 7, A-1140 Vienna, Austria. 31 Plant Molecular Biology Laboratory, Institute of Biotechnology, University of Helsinki, FI-00014 Helsinki, Finland. 32 Department of Biological and Environmental Sciences, University of Helsinki, FI-00014 Helsinki, Finland. 33 Department of Biology, 200014, University of Turku, FI-20014 Turku, Finland. 34 Southern Institute of Forest Genetics, United States Department of Agriculture, Forest Service and Department of Forest Science, Texas A&M University, College Station, TX 77843, USA. 35 Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA. 36 Department of Molecular Sciences and Center of Excellence in Genomics and Bioinformatics, University of Tennessee, Memphis, TN 38163, USA. 37 Southern Institute of Forest Genetics, United States Department of Agriculture, Forest Service, Saucier, MS 39574, USA. 38 Developmental Genetics, University of Tübingen, D-72076 Tübingen, Germany. 39 Department of Biotechnology, KTH, AlbaNova University Center, SE-106 91 Stockholm, Sweden. These authors contributed equally to this work as second authors