1. Department of Forest Biodiversity; University of Agriculture in Cracow; 29 Listopada 46 31-425 Cracow Poland
2. Department of Plant Sciences; Norwegian University of Life Sciences; PO Box 5003 1432 Ås Norway
3. Department of Plant Cytology and Embryology; University of Gdańsk; Wita Stwosza 59 80-308 Gdańsk Poland
4. Department of Plant Physiology; The Pedagogical University of Cracow; Podchorążych 2 30-084 Cracow Poland
5. Department of Plant Cytology and Embryology; Jagiellonian University; Gronostajowa 9 30-387 Cracow Poland