1. Research Centre for Plant Growth and Development, School of Life Sciences; University of KwaZulu-Natal Pietermaritzburg; P/Bag X01 Scottsville 3209 South Africa
2. Institute of Plant Biology, Faculty of Agricultural and Food Science; University of West Hungary; Mosonmagyaróvár H-9200 Hungary
3. Laboratory of Growth Regulators; Palacký University & Institute of Experimental Botany AS CR; Šlechtitelů 11 Olomouc CZ-783 71 Czech Republic
4. Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science; Palacký University; Šlechtitelů 11 Olomouc CZ-783 71 Czech Republic