1. Institute for Agricultural and Fisheries Research (ILVO), Plant Sciences Unit, Caritasstraat 21, 9090 Melle, Belgium.
2. KATHO Catholic University College of South-West Flanders, Department of Health Care and Biotechnology, Wilgenstraat 32, 8800 Roeselare, Belgium.
3. Ghent University, Faculty of Bioscience Engineering, Department for Plant Production, Coupure links 653, 9000 Gent, Belgium.