1. Department of Molecular Mechanisms of Phenotypic Plasticity; Institut de Biologie Moléculaire des Plantes du C. N. R. S.; Rue du Général Zimmer 12 67084 Strasbourg France
2. Imperial Tobacco Bergerac; La Tour 24100 Bergerac France
3. National Agricultural Research and Innovation Centre; Research Institute for Viticulture and Enology; Experimental Station of Kecskemét; PO Box 25 Kecskemét H-6001 Hungary