1. Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria 0002, South Africa
2. Natural Resources Canada – Canadian Forest Service, Great Lakes Forestry Centre, Sault Ste. Marie, Ontario, Canada
3. Department of Zoology and Entomology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria 0002, South Africa
4. Ontario Forest Research Institute, Ministry of Natural Resources and Forestry, Sault Ste. Marie, Ontario, Canada