Genome sequence initiatives

The possibility to access a complete genome sequence allows the development of new resources for high-throughput functional analysis without a priori, whole genome syntenic approaches for the detection of badly predicted genes or of conserved regulatory boxes. It also facilitates the identifi cation of key genes by combined genetic and genomics approaches. Two parallel projects using different strategies for the sequencing of the grapevine genome were initiated. The fi rst one aimed at the development of a reference genome sequence using a near homozygous genotype and the second one at the sequencing of a highly heterozygous high quality cultivar. Beside giving access to two annotated draft sequences of the genome of Vits vinifera L., the two projects developed genomic resources such as BAC libraries, BAC end sequences, sequenced full length cDNA libraries, physical and genetic maps. They offer very good material to assess the infl uence of heterozygosity on the development of physical maps or whole genome shotgun sequences and a fi rst rough view on the polymorphism between the two haplotypes of a grapevine variety. Finally, they provided a fi rst picture of the grapevine highly heterozygous genome, with a structure not much rearranged from the genome of its ancient hexaploid ancestor and the expansion of specifi c gene families

Molecular strategies to enhance the genetic resistance of grapevines to powdery mildew

The Eurasian winegrape Vitis vinifera has little or no genetic resistance to the major fungal pathogens, powdery mildew (Erysiphe necator) and downy mildew (Plasmopora viticola). These pathogens were first introduced into French vineyards from North America in the 1800s before spreading to all major grape producing regions of the world. As a result, grape production is highly dependent on the use of fungicides. With the increasing financial and environmental costs of chemical application and the emergence of fungicide-resistant strains, the introduction of natural genetic resistance against these fungal pathogens is a high priority for viticultural industries worldwide. We are utilising a number of different molecular approaches to increase our understanding of the basis of resistance to these important major fungal pathogens and to identify potential new sources of genetic resistance. This review will outline the progress and the potential of each of these different molecular strategies to the generation of fungal-resistant grapevine germplasm

Resistance to Plasmopara viticola in grapevine Bianca is controlled by a major dominant gene causing localized necrosis at the infection site

9Downy mildew resistance is a quantitative trait in grapevines of the genus Vitis. The grapevine 'Bianca' has retained resistance, originally present in its North American ancestors, through several cycles of backcrossing with susceptible cultivars of Vitis vinifera followed by phenotypic selection. The genetic control of the trait was studied using 116 full-siblings from the cross 'Chardonnay' x 'Bianca' and parental genetic maps consisting of 298 and 312 markers, respectively. Ratings of resistance and histological identification of the stage of interaction, when pathogen development is impaired in resistant individuals, were performed using leaf disc inoculation assays with two isolates of Plasmopara viticola collected in Italian and French vineyards. 'Bianca' and 59% of its offspring were heterozygous for a dominant gene, located in a 2.9 cM interval at the Rpv3 locus on chromosome 18, responsible for the onset of a hypersensitive response (HR) at the infection sites within 2 days post inoculation (dpi). Localised necrosis was the earliest phenotypic difference compared to susceptible individuals, it did not halt pathogen growth, but it was associated with a significant reduction of pathogen performance and disease symptoms from 3 to 6 dpi. QTL peaks for quantitative ratings revealed the strongest effects being caused by the Rpv3 locus: extent of mesophyll colonisation (LOD 3.1, percentage of explained phenotypic variance 16.2%), sporulation density (29.7, 74.3%), and symptom severity expressed by the OIV452 descriptor recommended by the Office International de la Vigne et du Vin (28.3, 74.6%). Strong correlation was observed between the ability of a seedling to mount an HR under controlled experimental conditions and quantitative resistance of the adult plant exposed to natural infections in the field, which was expressed by the number of leaves with fungal sporulation, in two consecutive years of observations.DOI 10.1007/s00122-007-0680-4reservedmixedBELLIN Diana; PERESSOTTI Elisa; MERDINOGLU Didier; WIEDEMANN-MERDINOGLU Sabine; ADAM-BLONDON Anne Francoise; CIPRIANI Guido; MORGANTE Michele; TESTOLIN Raffaele; DI GASPERO GabrieleBellin, Diana; Peressotti, Elisa; Merdinoglu, Didier; WIEDEMANN MERDINOGLU, Sabine; ADAM BLONDON Anne, Francoise; Cipriani, Guido; Morgante, Michele; Testolin, Raffaele; DI GASPERO, Gabriel

Alcohol and wine in relation to cancer and other diseases

Heavy alcohol consumption is associated with increased overall mortality, cancer, liver, and cardiovascular diseases; but low doses of alcohol (up to one drink per day) are not associated with the risk of any cancer site with the exception of breast cancer and possibly of oral and pharyngeal cancers. Moreover, recent evidence indicates that moderate alcohol and specifically wine intake provides cardioprotection and neuroprotection and may increase longevity. Various experimental data hypothesize a potential cancer chemopreventive role of some grape extracts, and complete sequencing of the grapevine genome has revealed genes responsible for the synthesis of health-promoting compounds (resveratrol and other polyphenols), thus advocating the development of future potential nutraceutical strategies. This focuses on the pros and cons of moderate alcohol and wine consumption and opens a debate on this topi