Naturalised grapevines collected from arid regions in N orthern C hile exhibit a high level of genetic diversity

Background and Aims Grapevine introduction into S outh A merica occurred after S panish colonisation during the 16th century. In C hile, some vines were established in small villages and oases along the A tacama D esert. Considering that these plants have survived harsh environmental conditions, we explored and collected naturalised vines from 18°34′ LS (close to the P eruvian border) to 31°53′ LS , in order to understand their genetic nature and preserve this germplasm. Methods and Results Over 150 grapevine accessions were collected and characterised using 11 Simple Sequence Repeats ( SSR ) markers, to determine the genetic diversity and to propose a population structuring. SSR diversity was high, with observed heterozygosity ( H o  = 0.87) greater than expected heterozygosity ( H e  = 0.70). Three discrete genetic groups were identified, which did not show any association with geographical distribution. Groups 1 ( G1 ) and G3 had a higher level of genetic diversity and also an important level of heterozygosity. Conclusions The gene pool of naturalised grapevines from the A tacama D esert had a significant genetic diversity and exhibited an important level of heterozygote excess. Clustering of this diversity suggested that this naturalised grapevine germplasm would represent a novel source of allelic variants. Significance of the Study Naturalised and admixed genotypes are potential sources of new alleles, and are a unique source of diversity for grapevine breeding cultivars and/or rootstocks better adapted to the prospect of climate change.