Patrimonial grapevine varieties (Vitis vinifera L.) from Rapa Nui: genetic characterisation and relationship with continental cultivars

Grapevines (Vitis vinifera L.), together with other fruit crops, were introduced on multiple occasions to Rapa Nui (Easter Island) after its European discovery, as early as 1821. Today, viticulture arises as a new innovative economic resource for Rapa Nui, and therefore, understanding which genotypes were introduced and their origin becomes not just a curiosity but a relevant issue. To answer these two questions, here we review documentary sources combined with genetic analyses of 65 samples of feral vines currently growing on the island using the set of nine microsatellites proposed by the International Organisation of Vine and Wine (OIV) and the Vitis International Variety Catalogue (VIVC). Among them, we found six genotypes with variable prevalence, including the two foundational varieties of American viticulture (Listan Prieto and Muscat of Alexandria), three criolla varieties (Huevo de Gallo/Huasquina/Blanca Ovoide, Rosa del Peru, and NN-165), and one unknown variety (named NN-416), which based on its SSR haplotypic pattern probably had a direct European ancestry. Except for NN-416, all the identified genotypes are commonly found in the Chilean central valley. These results strongly suggest that most of these plants were introduced from mainland Chile sometime during the second half of the 19th and early 20th centuries and remained uncultivated during all this time.