Large-scale screening of unknown varieties in a grapevine intra-varietal variability collection

Since the last decade of the last century, it is known that many old grapevine varieties are descendants of other varieties through natural crossing. Portugal has an important program for the conservation of representative samples of intra-varietal variability of all autochthonous varieties, managed by the Portuguese Association for Grapevine Diversity (PORVID), which makes looking for genotypes with dubious identification an important activity from a perspective of its valorisation. This communication presents the results of the molecular analysis of 5,000 samples (accessions) from the PORVID’s collection, using nine microsatellite loci currently recommended by the International Organization of Vine and Wine (OIV) for genetic grapevine identification. The results obtained confirmed the molecular identity of 4,220 samples corresponding to 214 varieties present in the official list of Portuguese varieties. In 780 samples, 95 profiles with a plural number of accessions revealed not to be listed in the Vitis International Variety Catalogue (VIVC) database, corresponding to possible varieties either descendent from natural crossing from at least one known parental variety, or from undetermined origin. Furthermore, the need for a comprehensive strategy aimed at uncovering other hidden varieties is discussed to prevent their imminent loss, deepen understanding of their origin, and add economic value and sustainability to the vine and wine sector.