Molecular and morphological diversity of on-farm hazelnut (Corylus avellana L.) landraces from southern Europe and their role in the origin and diffusion of cultivated germplasm

Hazelnut (Corylus avellana L.) is a traditional nut crop in southern Europe. Germplasm exploration conducted on-farm in five countries (Portugal, Spain, Italy, Slovenia, and Greece) identified 77 landraces. The present work describes phenotypic variation in nut and husk traits and investigates genetic relationships using ten simple sequence repeat (SSR) markers among these landraces, 57 well-known references cultivars, and 19 wild accessions. Among the 77 landraces, 42 had unique fingerprints while 35 showed a SSR profile identical to a known cultivar. Among the 42 unique landraces, morphological observations revealed high phenotypic diversity, and some had characteristics appreciated by the market such as nut round and caliber. Analysis of genetic relationships and population structure allowed investigation of the origin and spread of the cultivated germplasm in southern Europe. Our results indicate the existence of three primary centers of diversity in the Mediterranean basin: northwestern Spain (Tarragona) and southern Italy (Campania) in the West and Black Sea (Turkey) in the East. Moreover, the data suggest the existence of secondary gene pools in the Iberian (Asturias) and Italian (Liguria and Latium) Peninsulas, where local varieties were recently domesticated from wild forms and/or from introduced ancient domesticated varieties

PCR analysis of experimental and commercial wines by means of nuclear and chloroplast SSRs

Genetic identification of varieties of grapevines in finished wines is still debated: several papers showed that DNA is extracted and analysed by PCR rather easily from the must, but few barely reproducible results have been presented for DNA extracted in wines after fermentation. This work experimented a method based on CTAB followed by silica purification with NucleoSpin Plant Kit columns to extract DNA from experimental wines of 1 year and commercial wines of 1 or 2 years. The comparison of SSR profiles of wines with those of their grapevine varieties showed that total identity was equal to 47.41% in experimental wines and to 24.31% in commercial wines. In experimental wines, three PCR replicates of three independent DNA preparations are sufficient to capture the alleles of the original grapevine variety, while in the commercial ones this possibility is related to the kind of wine and microsatellite