Vitis 44 (4), 167–172 (2005) Molecular characterization of officially registered Sangiovese clones and of other Sangiovese-like biotypes in Tuscany, Corsica and Emilia-Romagna I. FILIPPETTI, C. INTRIERI , M. CENTINARI, B. BUCCHETTI, and C. PASTORE Dipartimento di Colture Arboree, Cattedra di Viticoltura, Sezione Viticola del Centro Interdipartimentale di Ricerche Viticole ed Enologiche, Università di Bologna, Bologna, Italy Correspondence to: Prof. Dr. C. INTRIERI, Dipartimento di Colture Arboree, Cattedra di Viticoltura, Sezione Viticola del Centro Interdipartimentale di Ricerche Viticole ed Enologiche, Università di Bologna, Viale Giuseppe Fanin 46, 40127 Bologna, Italy. Fax: +39- 051-2096401. E-mail: viticolt@agrsci.unibo.it Summary The present study was designed (1) to identify and de- termine the origin of the genetic variability via SSR and AFLP within a group of 39 Sangiovese clones officially listed in the National Grapevine Registry, (2) to pinpoint varietal differences and potential family relations among 34 Sangio- vese-like biotypes, via the SSR markers. Most biotypes are regarded as Sangiovese but sometimes are known under different names. In both studies the reference standard was the registered Sangiovese clone SG 12T. No polymorphism was found among the officially listed 39 clones analysed at 6 microsatellite loci. This enabled us to confirm their origin from a single mother plant, thereby supporting the view that any morphological or qualitative differences may be the result of propagation-related muta- genic events. A subsequent AFLP analysis of 26 of the 39 clones showed polymorphic bands in three of them (two identical) that may correspond to a mutagenic event. Assays with SSR markers on 34 Sangiovese-like biotypes collected in Tuscany, Corsica and Emilia-Romagna showed that 28 are identical with the reference Sangiovese clone SG 12T, while the remaining 6 (Sangiovese 1, Sangio- vese 6, Morellino, Poverina, Sangiovese forte and Brune- llone) are genetically different from SG 12T and among one another so that no direct family relations could be es- tablished. K e y w o r d s : Vitis vinifera, Sangiovese, microsatellite (SSR), amplified fragment length polymorphism (AFLP), cultivar, clone. Introduction Certain grapevines evince intra-cultivar variability that, if environmental and viral causes are ruled out, may be as- cribed either to bud mutations that arose during agamic propagation from a single mother plant, or to agamic multi- plication, with or without mutagenic events from seed-de- rived, closely related and morphologically similar individu- als (RIVES 1961). In the first instance, current DNA assays using microsatellites (SSRs) do not appear to be capable to detect any genetic differences arising from bud mutations in the course of agamic descendance from a single mother plant (THOMAS and SCOTT 1993, BOWERS et al. 1996, SILVESTRONI et al. 1997, SEFC et al. 1998). The only exceptions reported involve differences among biotypes of the Pinot group im- putable to periclinal chimeras and shown to have more than two alleles at a single SSR locus (FRANKS et al. 2002). While only a few specific cases are reported in literature, genetic differences among mutated biotypes deriving from a single mother plant have been found using AFLPs (amplified frag- ment length polymorphisms), which are potentially better suited for this purpose (CERVERA et al. 1998, SCOTT et al. 2000, BELLIN et al. 2001). In the second instance of variabil- ity arising from a few closely related, seed-derived individu- als, the inter-biotype genetic differences are readily discern- ible via several kinds of markers. Of these, SSRs are particu- larly useful because of their polymorphic and co-dominant traits and because they can determine the dimension in base pairs of alleles at each locus both, in cultivar identification (THOMAS et al. 1994, BOWERS et al. 1996, FILIPPETTI et al. 2001) and in studying inter-varietal relations (BOWERS and MEREDITH 1997, SEFC et al. 1998). The present study investigates the genetic basis of vari- ability of a number of registered Sangiovese clones and at- tempts to establish the identity or the varietal diversity and any kinship relations in a group of randomly collected but as yet not definitively named grape accessions. Material and Methods The first investigation was carried out on 39 Sangiovese clones listed in the National Grapevine Variety Registry (Tab. 1), and the second on 34 new accessions largely thought to belong to cv. Sangiovese but locally known to have different names (e.g. Morellino, Chiantino, Nielluccio). These 34 Sangiovese-like accessions were found during ampelographic surveys conducted in Tuscany, Corsica and Emilia-Romagna (Tab. 2). The registered Sangiovese SG 12T clone was need as reference in both assays. Young leaves of individual vines were taken from the variety collections at the nursery Vivai Cooperativi in Rauscedo and at the Departments of Horticulture and of Fruit Tree and Woody Plant Science, Universities of Flor- ence and Bologna. Their DNA was extracted with the DNeasy® Plant Mini Kit (Qiagen, Milan) and quantified with an ND-100 spectrophotometer (Nanodrop, Wilmington, DE). All the samples in both investigations were assayed using