1. Institute for Agricultural and Fisheries Research, Plant Sciences Unit, Growth and Development, B-9090 Melle, Belgium
2. Bioinformatics Institute Ghent, Ghent University, B-9052 Ghent, Belgium
3. Department of Plant Systems Biology, VIB, Technologiepark 927, B-9052 Ghent, Belgium
4. Department of Plant Biotechnology and Bioinformatics, Ghent University, B-9052 Ghent, Belgium