1. Production Systems, Natural Resources Institute Finland (LUKE), Joensuu, North Karelia 80100, Finland
2. School of Forest Sciences, University of Eastern Finland, Joensuu, North Karelia 80100, Finland
3. Natural Resources, Natural Resources Institute Finland (LUKE), Uusimaa, Helsinki 00790, Finland
4. Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0028, South Africa