1. State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Silviculture of the State Forestry AdministrationResearch Institute of Forestry, Chinese Academy of Forestry Beijing 100091 China
2. Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences and TechnologyBeijing Forestry University Beijing 100083 China
3. Forest Botany and Tree PhysiologyUniversity of Goettingen 37077 Göttingen Germany
4. Institute for Forest SciencesUniversity of Freiburg 79110 Freiburg Germany