1. Institute of Agronomy, University of Natural Resources and Life Science, Vienna, 3430 Tulln an der Donau, Austria
2. Institute of Botany, University of Natural Resources and Life Science, Vienna, 1180 Vienna, Austria
3. Institute of Mathematics, University of Natural Resources and Life Science, Vienna, 1180 Vienna, Austria
4. Experimental Farm, University of Natural Resources and Life Science, Vienna, 2301 Groß-Enzersdorf, Austria