GENETIC SIMILARITIES AMONG WINE GRAPE CULTIVARS REVEALED BY RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISM (RFLP) ANALYSIS

RFLP data were used to assess genetic similarity among 33 Vitis vinife ra L. cultivars and one interspecific cultivar. A similarity matrix wa s constructed on the basis of the presence or absence of 49 bands gene rated by eight RFLP probes and cluster analysis was performed. The mea n similarity index for all pairwise comparisons was 0.696 and ranged f rom 0.444 between 'St. Emilion' and the interspecific hybrid 'Salvador ' to 0.952 between 'Chenin blanc' and 'Semillon'. Mean similarity amon g all V. vinifera cultivars was 0.705. Several groupings of similar cu ltivars are consistent with historical reports and presumed geographic origins: 'Chardonnay' and 'Melon', 'Colombard' and 'Folle blanche', ' GeWurztraminer' and 'Trousseau', 'Cabernet franc' and 'Cabernet Sauvig non', 'Mission' and 'Palomino', The similarity between 'Mission' and ' Palomino' is the first genetic evidence to support the putative Spanis h origin of 'Mission'. Some groupings are unexpected ('Sauvignon blanc ' and 'Gewurztraminer', 'Chenin blanc' and 'Semillon') because the cul tivars are not thought to have originated in the same regions. While s ome relationships suggested by this study may be artifacts of RFLP ana lysis or of the statistical method, they raise questions for further g enetic inquiry into the origins of grape cultivars.