Phenological Diversity of Georgian Grapevine Cultivars in Northern Italy

One hundred thirty four Georgian native grapevine (Vitis vinifera L.) cultivars were tested in a field collection, located in Gorizia, Northern Italy within the framework of the international project of Bioversity International "Conservation and sustainable use of grapevine genetic resources in the Caucasus and Northern Black Sea area". Phenological timing and grape ripening profiling were recorded in the three year period 2004-2006. Average multi-year phenological data demonstrated that the timing of bud break and flowering of the Georgian germplasm was slightly later when compared with Westem European cultivars. Veraison timing was clearly later and showed a very wide time span. Ripening time was, on average, also late. Ripening profiles in terms of juice soluble sugar concentration, pH and titratable acidity were ample; few cultivars were unable to reach an adequate maturity. The Georgian grape cultivars were separated into four main groups according to their time of ripening.