1. Leibniz Institute of Vegetable and Ornamental Crops, Theodor-Echtermeyer-Weg 1,14979 Großbeeren, Brandenburg, Germany and Institute of Biology, Plant Physiology Department, Humboldt University of Berlin, Philippstraße 13, 10115 Berlin, Germany
2. Department of Plant Anatomy, Institute of Biology, Eötvös Loránd University, Pázmány Péter sétány 1/C, 1117 Budapest, Hungary
3. Plant Protection Institute, Centre for Agricultural Research, Budapest 1022, Hungary
4. Erfurt Research Centre for Horticultural Crops, University of Applied Sciences, Kühnhäuser Straße 101, 99090 Erfurt, Thuringia, Germany