In situ and genetic characterization of wild grapevine populations in the Castilian and Leon region (Spain)

Aim: Assessing levels and patterns of population genetic variation in combination with morphological characterization represents an important step for evaluating rare or endangered species and determining appropriate conservation strategies. This is particularly important for ensuring the preservation of valuable genetic variation in wild relatives of crops, which could provide beneficial alleles for plant breeding and improvement. Methods and results: A survey of the relict wild grapevine population was carried out in the province of Burgos, in the Castilian and Leon region (Spain). Genetic diversity, inbreeding extent and possible hybridization with cultivated grapevine were investigated using molecular markers. Results showed that overall, genetic diversity was low but inbreeding was not present. Private alleles were found in the Burgos wild genotypes, suggesting the potential value of these accessions. Comparisons of morphological traits and molecular features among the wild population showed a close genetic relationship among them and no genetic relationship to Castilian grapevine cultivars. Conclusion: The genetic differentiation observed between wild and domesticated forms of grapevine points out the interest to characterize and conserve the existing populations as a source of novel alleles for future grapevine breeding programs. At the same time, the observed enological differences between wild and domesticated grapevine populations could be interesting for the wine industry. Finally, given that these populations are at severe risk of extinction, we recommend that this population be prioritized for ex situ and possibly on-farm conservation as well as in situ protection. Significance and impact of the study: This work showed the existence of novel alleles and enological characters in natural wild grapevine populations, which represents a first step in the potential contribution of these natural populations to viticulture, suggesting a possible role in future breeding programs.