Two researchers in Italy have unveiled a possible list of parents, offspring, cousins and clonal variations for Nebbiolo, the preeminent grape variety of Italy's Piedmont region.
Anna Schneider, an Italian expert on grapevine identification, who works at the Centro Nazionale di Ricera in Turin, and José Vouillamoz from the Instituto Agrario di San Michele all'Adige, discussed Nebbiolo at the first International Convention on Nebbiolo, held last week in the Valtellina region.
According to the two, Nebbiolo is closely related to a number of less widely known northern Italian grape varieties: Nebbiolo Rosé, Freisa, Negrera, Rossola, Vespolina and Bubbierasco. Although the precise relationships are not yet clear, one or more of these grape varieties may be the parents or offspring of Nebbiolo.
In addition, Nebbiolo Rosé, formerly considered a clone of Nebbiolo and permitted for use in Nebbiolo wines, is actually an entirely different grape variety, said Vouillamoz. This discovery could cause problems for Italian producers of wines such as Barolo, Barbaresco and Nebbiolo d'Alba, which are required by law to be 100 percent Nebbiolo.
Vouillamoz, who spent a year working at the University of California, Davis, in the lab of noted grapevine geneticist Carole Meredith, and Schneider tested DNA samples of Nebbiolo against samples of DNA from more than 1,500 grape cultivars gathered from countries around the world.
Preliminary work suggests a similar genetic relationship between Freisa, a red variety long believed to be native to Piedmont, and Viognier, the aromatic white Rhône grape variety, said Schneider. That means that Viognier and Nebbiolo may ultimately be distant relations.