Twenty microsatellites (SSRs) reveal two main origins of variability in grapevine cultivars from Northwestern Spain

Abstract

The grapevine germplasm bank in the “Estación de Viticultura y Enología de Galicia, Xunta de Galicia”, holds fifteen grapevine cultivars with a total of 98 accessions: ‘Brancellao’, ‘Albarello’, ‘Caíño Astureses’, ‘Caíño Bravo’, ‘Caíño Blanco’, ‘Caíño Gordo’, ‘Albarín Negro’, ‘Caíño Longo’, ‘Caíño Redondo’, ‘Castañal’, ‘Mencía’, ‘Merenzao’, ‘Mouratón’, ‘Sousón’, and ‘Verdello’. Cultivars ‘Syrah’ and ‘Pinot Noir’ were included as references. Two different lineages were detected, one originating in ‘Caíño Astureses’ and the other in ‘Merenzao’, synonymy of the French cultivar ‘Trousseau’. Cultivars from Northwestern Spain derived from both of these cultivars by hybridization and selected genotypes that had adapted to local climatic conditions and became fixed by cuttings, explaining the domestication process of these grapevine cultivars. Both lineages differed in allelic frequencies and were distributed differently in Northwestern Spain, the first lineage in the west and the second, related with the French cultivar ‘Trousseau’, in the east. ‘Caíño Astureses’ was the most frequent genotype related by hybridization, indicating the importance that this cultivar had in the origin of grapevines in Galicia. In addition a total of 13 different genotypes were identified. The identity of ‘Brancellao’ and ‘Albarello’ was confirmed by SSR-markers. Other two synonyms were ‘Caíño Astureses’ and ‘Caíño Bravo’, and ‘Caíño Gordo’ and ‘Albarín Negro’. ‘Caíño Redondo’ showed two different genotypes, one related to ‘Caíño Astureses’ and the other to ‘Merenzao’. Two cultivars included in the collection from EVEGA were not reported previously, ‘Verdello’ and ‘Caíño Longo’.