1. University of Alberta; Department of Renewable Resources; Edmonton AB T6G 2E3 Canada
2. Connecticut College; Department of Botany; New London CT 06320 USA
3. University of Hradec Králové; Department of Biology; Rokitanského 62 Hradec Králové 500 03 Czech Republic
4. Charles University; Department of Experimental Plant Biology; Viničná 5 Prague 128 44 Czech Republic