Genetic fingerprinting reveals how traditional farming practices aided to preserve ancient table grape varieties in Almería (southeastern Spain)

Abstract

Table grape production is a traditional practice in southeastern Spain, where locals have produced fresh grapes and raisins for centuries. Many of these vines are now centenary, and they represent a useful source of diversity for developing future table grape varieties with improved traits. Genetic analysis showed that many of the local varieties identified in this study were traditional varieties from Western Mediterranean countries. Others were not identified, and they might be old grape varieties of previous importance in the region. The conservation and characterization of these varieties could be key to ensuring current and future vineyard sustainability. Current worldwide table grape production focuses on a reduced number of Vitis vinifera L. varieties. However, traditional farmers have grown many table grape varieties for centuries, as they provided a steady source of fresh fruit and raisins. These ancient living genotypes potentially store a genetic diversity that can be used now to ensure future grape production. Here we focused on the study of grapevines found across Almería, one of the Spanish regions with longer tradition in table grape production. After an exhaustive inspection, we located 220 old (some centenary) vines producing grapes consumed by owners or in abandoned areas no longer devoted to agriculture. Some of these vines were identified by comparing their simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) genetic profiles with available data from international databases. We found that, while grape growers' efforts focused on the cultivation of traditional grape varieties from Western Mediterranean regions, they also cultivated few exogenous varieties if they provided additional fruit features. Other vines were found to have genetic profiles that did not match reference datasets. Interestingly, some of them were found in multiple locations, suggesting they are endangered varieties with some previous relevance in the region. Besides, first‐degree relationships support the autochthonous origin of many of these unidentified genotypes. Locals kept a high number of different grapevine varieties, now considered reservoirs of genetic diversity. Traditional farming practices have been useful to prevent the loss of this diversity, which now needs to be preserved and further studied to contribute to the sustainability of viticultural systems.