1. The Institute for Plant Sciences and Genetics in Agriculture; The Robert H. Smith Faculty of Agriculture; Food and Environment; Hebrew University of Jerusalem; Rehovot 76100 Israel
2. Institute of Crop Science; Section Crop Physiology of Specialty Crops; Hohenheim University; Stuttgart D-70599 Germany
3. Institute of Plant Science; ARO; The Volcani Center; Bet Dagan 50250 Israel