The domestication of the Eurasian grape ( Vitis vinifera ssp. sativa ) from its wild ancestor ( Vitis vinifera ssp. sylvestris ) has long been claimed to have occurred in Transcaucasia where its greatest genetic diversity is found and where very early archaeological evidence, including grape pips and artefacts of a 'wine culture', have been excavated. Whether from Transcaucasia or the nearby Taurus or Zagros Mountains, it is hypothesized that this wine culture spread southwards and eventually westwards around the Mediterranean basin, together with the transplantation of cultivated grape cuttings. However, the existence of morphological differentiation between cultivars from eastern and western ends of the modern distribution of the Eurasian grape suggests the existence of different genetic contribution from local sylvestris populations or multilocal selection and domestication of sylvestris genotypes. To tackle this issue, we analysed chlorotype variation and distribution in 1201 samples of sylvestris and sativa genotypes from the whole area of the species' distribution and studied their genetic relationships. The results suggest the existence of at least two important origins for the cultivated germplasm, one in the Near East and another in the western Mediterranean region, the latter of which gave rise to many of the current Western European cultivars. Indeed, over 70% of the Iberian Peninsula cultivars display chlorotypes that are only compatible with their having derived from western sylvestris populations.

The wild grapevine, Vitis vinifera L. ssp. sylvestris (Gmelin) Hegi, considered as the ancestor of the cultivated grapevine, is native from Eurasia. In Spain, natural populations of V. vinifera ssp. sylvestris can still be found along river banks. In this work, we have performed a wide search of wild grapevine populations in Spain and characterized the amount and distribution of their genetic diversity using 25 nuclear SSR loci. We have also analysed the possible coexistence in the natural habitat of wild grapevines with naturalized grapevine cultivars and rootstocks. In this way, phenotypic and genetic analyses identified 19% of the collected samples as derived from cultivated genotypes, being either naturalized cultivars or hybrid genotypes derived from spontaneous crosses between wild and cultivated grapevines. The genetic diversity of wild grapevine populations was similar than that observed in the cultivated group. The molecular analysis showed that cultivated germplasm and wild germplasm are genetically divergent with low level of introgression. Using a model-based approach implemented in the software structure, we identified four genetic groups, with two of them fundamentally represented among cultivated genotypes and two among wild accessions. The analyses of genetic relationships between wild and cultivated grapevines could suggest a genetic contribution of wild accessions from Spain to current Western cultivars.

Genetic structure of six Italian and five Spanish populations of wild grapevine (Vitis vinifera ssp. silvestris) was investigated using nuclear and chloroplast SSR analysis. Results show that the Italian populations are characterised by high genomic diversity within populations, with a peak of heterozygosity (Ho = 0.7637) for a population collected in southern Italy. However, the low haplotype richness and the high level of genetic distance detected among the Spanish populations, combined with their low gene flow, shows that these populations suffered from a genetic erosion. Genetic relationship between Italian and Spanish populations was investigated and results showed genetic differentiation between the two populations. Using nuclear and chloroplast SSR markers, the ratio between pollen and seed diffusion was estimated. High pollen flow, as compared with seed flow, suggests that seed diffusion is made difficult, probably due to low germinability and survival of seedlings in the wild. Seed germination and young plant survival must be considered a priority target for in situ conservation programmes. By providing information on population history, genetic structure and gene flow, and by identifying areas harbouring high levels of wild grape variability, this study provides the basis for the preservation of biodiversity of the wild grapevine.

Twenty-six populations of Vitis vinifera subsp. silvestris, a wild dioecious relative of cultivated grapevine, were found in the autonomous Basque Region in Spain and the Department of the Pyrénées Atlantiques in France. Of these populations, 76% had less than 10 individuals. Similarly to most European populations of wild grapevines, these were found on forest edges, where human pressure is enormous. Despite considerable pest and pathogen loads on the surrounding vineyards, wild grapevines were not particularly affected. In some cases, ecological conditions were not sufficient for the development of the pests and pathogens, but in most cases this low infestation seemed to be due to different degrees of tolerance. The level of susceptibility varied between individuals of the same population. Additionally, tolerance of wild grapevine to salt and calcareous was detected.

Abstract. The Farkas-Minkowski systems are characterized through a convex cone associated to the system, and some sufficient conditions are given that guarantee the mentioned property. The role of such systems in semi-infinite programming is studied in the linear case by means of the duality, and, in the nonlinear case, in connection with optimality conditions. In the last case the property appears as a constraint qualification.