Negretta

Nielluccio is a red wine grape variety that is widely planted on Corsica. It is the principal grape variety used in the production of the Appellation d'Origine Contrôlée AOC red wine Patrimonio, where it must by law make up 95% of the blend. An early budding vine, Nielluccio produces wines lacking in color and with high alcohol levels. It is commonly used to make rosé wine.

There is confusion about the grape's exact origins with some wine experts describing the grape as being indigenous to Corsica while other theories report that the grape is of Italian origins and possibly even a genetically identical clone of the Tuscan wine grape Sangiovese that came to Corsica from Genoa.

The exact origins of Nielluccio are disputed. While the grape is today known as primarily a French, or more specifically, Corsican grape,ampelographers in the late 20th century began to believe that the grape was likely of Italian origins. Nielluccio's close genetic similarities to the indigenous Italian variety Sangiovese suggest that the two grapes are closely related. The grape was likely introduced to Corsica by the Genoese during their long rule over the island from the 13th century to the 18th century. But this view is not universally accepted with some wine experts, such as Oz Clarke, believing that the grape is indigenous to Corsica. Even Jancis Robinson believed once that Nielluccio was native to Corsica but her more recent works give support to the Genoese theory.

To further add to the mystery, there is some belief that the extremely close genetic similarities between Sangiovese and Nielluccio could mean that they are exactly the same grape (or rather a clone given Sangiovese's propensity for mutation). Indeed, the German Vitis International Variety Catalogue data base of known grape cultivars does not even give Nielluccio a separate entry, rather grouping it in as a synonym of Sangiovese. Still many French and English wine texts, such as the Oxford Companion to Wine, list the grape as a separate entry but with a note describing its close similarities to Sangiovese.

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