1. Department of Forest Genetics and Forest Tree Breeding , Georg-August University of Göttingen , Büsgenweg 2 , Göttingen , Germany .
2. Center for Integrated Breeding Research (CiBreed) , Georg-August University of Goettingen , Göttingen , Germany
3. Centre of Biodiversity and Sustainable Land Use , Georg-August University of Göttingen , Göttingen , Germany