Vineyards genetic monitoring and Vernaccia di San Gimignano wine molecular fingerprinting

Abstract

The definition of the genetic\rprofile of Vernaccia di San Gimignano (VSG) in the areas of production is an\ressential step for both the implementation of a plan of analytical traceability\rand the evaluation of the biological future potential of the same grape variety\rin relation to any environmental change. The genetic variability of the VSG was\rmonitored by use of SSRs genotyping of a representative portion of individuals\rbelonging to both the productive vineyards and the germplasm collections that\rrepresent the “mother plants” reservoir for future vineyards. 74% of the\rindividuals have been shown to be identical to the grapevine genotype reported\rin databases as VSG truetype. In order to determine the wine varietal\rcomposition by DNA analysis, four wine types commercialized as VSG were\rDNA-tested at 14 loci SSRs. The molecular data obtained demonstrate the presence\ras prevalent component of the VSG in the four wine types. All the wines\rrevealed the presence of minor varieties, whose presence/absence was\restimated by extrapolating the allele configuration that best matched to a\rstandard genotype. Molecular data allow us to exclude the presence of three\raromatic white grapevines that are not allowed by the actual production rules\r(Disciplinare di Produzione).