1. D. Cai, M. Kleine, S. Kifle, H.-J. Harloff, C. Jung, Institute of Crop Science and Plant Breeding, Christian-Albrechts-University of Kiel, Olshausenstrasse 40, D-24118 Kiel, Germany.
2. N. N. Sandal and K. A. Marcker, Laboratory of Gene Expression, Department of Molecular and Structural Biology, University of Aarhus, Gustav Wieds Vej 10, DK-8000 Aarhus, Denmark.
3. R. M. Klein-Lankhorst, E. M. J. Salentijn, W. Lange, W. J. Stiekema, DLO-Centre for Plant Breeding and Reproduction Research (CPRO-DLO), Droevendaalsesteeg 1, NL-6700 AA Wageningen, Netherlands.
4. U. Wyss and F. M. W. Grundler, Institute of Phytopathology, Christian-Albrechts-University of Kiel, Olshausenstrasse 40, D-24118 Kiel, Germany.