Duckweed cultures
Axenic cultures of the three duckweed species were maintained at the
Department of Evolutionary Biology and Environmental Studies, University
of Zürich. Three strains were delivered in July from the Landolt
Duckweed Collection (www.duckweed.ch). Lemna turionifera , strain
9478, sourced from Racibórz, Silesian, Poland, Lemna minor ,
strain 9978, sourced from Oberegg, Appenzell Innerrhoden, Switzerland,
and Lemna gibba , strain 9965, sourced from Schloss Wartensee,
Rorschacherberg, St. Gallen, Switzerland. The axenic cultures were held
on Hoagland’s E Medium (see Appendix for recipe used) in incubators at
18 °C with a light regime of 14/10h light/dark.