Microsatellite analysis of Alpine grape cultivars (Vitis vinifera L.): alleged descendants of Pliny the Elder’s Raetica are genetically related

Abstract

According to Pliny the Elder and other Greco-Roman geoponics, Raetica was a famous white grape as well as a white wine produced in Raetia, a Province of the Roman Empire. Does Raetica grape have modern descendants? Etymologically and geographically, the white 'Rè ze' from Valais (Switzerland) would be the best candidate. Using available microsatellite data, we searched for relatives of 'Rè ze' in our database containing over 1,700 genotypes of grape cultivars from all over the world. Twelve cultivars showing putative first-degree (parentoffspring or full-siblings) or second-degree (grandparent-grandoffspring, uncle-nephew or half-siblings) relationships with 'Rè ze' were then analysed at 60 microsatellite markers. Calculation of allele sharing and likelihood ratios between competing relationship categories revealed that four cultivars had parent-offspring relationship with 'Rè ze': 'Cascarolo Bianco' (Piedmont, Italy), 'Arvine Grande' (Valais, Switzerland), 'Groppello di Revò ' and 'Nosiola' (Trentino, Italy). Given that some of these are also said to be Raetica descendants, we may well be on the tracks of Pliny the Elder's Raetica grape. However, there is no evidence about the identity of Raetica. Analysis of ancient DNA of grape pips excavated from archaeological sites of the Roman times might provide key information. Our first attempts were unsuccessful, but analysis of additional samples and optimisation of the method could provide groundbreaking results about the identity of the grapes cultivated in classical antiquity.

Pedigree Reconstruction of the Italian Grapevine Aglianico (Vitis vinifera L.) from Campania

“…Kinship analysis was estimated twice, the first time on 21 SSR profiles and the second one on 43 SSR profiles. The D 7 , D 8 , and r coefficients were estimated basing on allelic frequency, so the assignment to the most likely relationship category was performed expanding the analysis to 12 Italian cultivars genotyped with 43 SSR markers and other varieties (up to 45 samples) reported in literature [12,15,[26][27][28], to have a more precise prediction. The samples reported in literature (Arvine grande, Calabrese di Montenuovo, Cascarolo bianco, Chasselas, Ciliegiolo, Completer, Cornalin d'Aoste, Cornalin du Valais, Dureza, Freisa, Goron, Groppello di Revò, Humagne, Lafnetscha, Lagrein, Madeleine Royale, Marzemino, Mayolet, Monduese blanche, Nebbiolo, Negrello, Nosiola, Petit rouge, Plantscher, Rèze, Roussin de Morgex, Sangiovese, Schiava grossa, Teroldego, and Vuillermin) were chosen because their molecular characterization was carried out using the major number of the 43 SSR markers and belonging to Italian and International germplasm.…”

“…In order to deeply investigate these relationships and to verify their significances, the number of analyzed SSR loci was increased to 43 for the three identified genotypes and for a set of 12 additional samples as previously reported. The number of samples was increased up to 45 adding allelic profile of varieties characterized in literature [12,15,[26][27][28], reporting data for the most part of the 43 SSR markers. The number of shared alleles per locus estimated for 43 SSR allelic profiles confirmed the results obtained by the genotyping with 21 SSR loci: Aglianico like-to-type and Aglianico trueto-type genotypes are linked by PO relationship.…”

Ancient plant DNA in archaeobotany

“…Surprisingly little genetic homogenization took place despite large cultivar diversity and intensive breeding of new cultivars, since microsatellite variability in modern cultivars is known to be structured geographically and at cultivar level (Sefc et al 2000;Aradhya et al 2003;This et al 2004). This permits speculation about the origin of historically known cultivars (Vouillamoz et al 2006) and comparison with ancient cultivars. Microsatellite loci have been used to investigate the origins of V. vinifera seeds preserved by waterlogging and charring at several European Celtic, Greek and Roman sites.…”

“…Fourthly, they are independent of recent cultural impact, and finally, aDNA studies enable us to test historical written sources (e.g. Vouillamoz et al 2006). …”

Morphology and Molecular Analysis of Ancient Grape Seeds

“…the molecular results were compared with national and international contemporary cultivars in data banks (sefc et al 1998;Bowers et al 1999;Vouillamoz et al 2006) and we submitted the data obtained with the seven (Vignani et al 2008). We observed a degree of microsatellite oscillation that enabled us to exclude contamination (cappellini et al 2010).…”