Search

“Suspect screening analysis”method to study grape metabolomics, was performed. This method is a middle-way “targeted” and “untargeted”approach aiming at identifying the largest number of metabolites in grape samples. A new database of putative grape and wine metabolites (GrapeMetabolomics), which currently contains around 1,100 compounds, was constructed by CREA at Conegliano. By performing high-resolution mass spectrometry analysis of the grape extract in both positive and negative ionization mode, averaging 320-450 putative compounds are identified. Most of them are grape polyphenols, such as anthocyanins, flavonols and stilbene derivatives. By performing PCA and Cluster Analysis the composition in anthocyanins and flavonols of 20 Italian red grape varieties, was studied.

“Suspect screening metabolomics” is a mid-way approach between “targeted” and “untargeted” analysis. For this aim, a new database of putative grape and wine metabolites (GrapeMetabolomics) was expressly constructed. Currently, this database contains around 1,100 compounds. By performing UHPLC/QTOF mass spectrometry analysis in both positive and negative ionization mode, in a grape extract averaging 320–450 putative compounds are identified. Most of these compounds are important grape metabolites, including flavonols, anthocyanins, and stilbene derivatives. In the present study, this approach was focalized on the characterization of flavonols of 18 important Italian red and white grape varieties and the method provided the identification of 15 flavonols. By performing statistical analysis (Principal Component Analysis and Cluster Analysis), the effect of the variety on the flavonol composition of the grapes was studied. Both the red and white samples fell into three different groups, respectively, on the basis of their flavonol profiles. Because the samples were cultivated in the same vineyard, their profile potentially was not affected by cultural or environmental factors. Anyway, these preliminary results will have to be confirmed by the study of grape samples collected in different years and from different vineyards.

The grapevine was one of the earliest domesticated fruit crops and has been cultivated since ancient times. It is considered one of the most important fruit crops worldwide for wine and table grape production. The current grape varieties are the outcome of prolonged selection initiated during the domestication process of their wild relative. Recent genetic studies have shed light on the origins of the modern domestic grapevine in western Europe, suggesting that its origin stems from the introgression between eastern domestic grapes and western wild grapes. However, the origin of ancient grapevines remains largely unexplored. In this study, we conducted an extensive analysis of 2228 well-preserved waterlogged archaeological grape pips from two sites in Sardinia (Italy), dated to the Late Bronze Age (ca. 1300–1100 BC) and the Iron Age (4th and 3rd centuries BC). Using morphometrics and linear discriminant analyses, we compared the archaeological grape pips with modern reference collections to differentiate between wild and domestic grape types and to investigate similarities with 330 modern cultivars. Grape pips from the Late Bronze Age displayed a high percentage of similarity with domesticated grapevines, with a small percentage assigned to wild ones, while the majority of grape pips from the Iron Age were classified as domestic. Discriminant analyses revealed that both white and red grape varieties were cultivated during the Late Bronze and Iron Ages, suggesting a high level of diversification in grape cultivation. Furthermore, a high percentage of archaeological grape pips from both periods showed strong similarities with modern cultivars from the Caucasus and Balkans. This suggests that the great diversity of grapevines present in Sardinia could result from interbreeding between western Asian cultivars and local grapevines that began in the Late Bronze Age. Additionally, a substantial proportion of archaeological grape pips exhibited similar morphometric characteristics to two important Mediterranean grape cultivars: "Muscat à petits grains blancs" and "Garnacha". [ABSTRACT FROM AUTHOR]

The importance of plants as complex entities influenced by genomes of the associated microorganisms is now seen as a new source of variability for a more sustainable agriculture, also in the light of ongoing climate change. For this reason, we investigated through metatranscriptomics whether the taxa profile and behaviour of microbial communities associated with the wood of 20-year-old grapevine plants are influenced by the health status of the host. We report for the first time a metatranscriptome from a complex tissue in a real environment, highlighting that this approach is able to define the microbial community better than referenced transcriptomic approaches. In parallel, the use of total RNA enabled the identification of bacterial taxa in healthy samples that, once isolated from the original wood tissue, displayed potential biocontrol activities against a wood-degrading fungal taxon. Furthermore, we revealed an unprecedented high number of new viral entities (~120 new viral species among 180 identified) associated with a single and limited environment and with potential impact on the whole holobiont. Taken together, our results suggest a complex multitrophic interaction in which the viral community also plays a crucial role in raising new ecological questions for the exploitation of microbial-assisted sustainable agriculture. [ABSTRACT FROM AUTHOR]

The Italian grape germplasm is characterized by a high level of richness in terms of varieties number, with nearly 600 wine grape varieties listed in the Italian National Register of Grapevine Varieties and with a plethora of autochthonous grapes. In the present study an extended SNP genotyping has been carried out on Italian germplasm of cultivated Vitis vinifera subsp. sativa and Vitis hybrids. Several hundred Italian varieties maintained in the repositories of scientific Institutions and about one thousand additional varieties derived from previous studies on European, Southern Italy, Magna Graecia and Georgian germplasm were considered. The large genotyping data obtained were used to check the presence of homonyms and synonyms, determine parental relationships, and identify the main ancestors of traditional Italian cultivars and closely-related accessions. The parentage among a set of 1,232 unique varieties has been assessed. A total of 92 new parent-offspring (PO) pairs and 14 new PO trios were identified. The resulted parentage network suggested that the traditional Italian grapevine germplasm originates largely from a few central varieties geographically distributed into several areas of genetic influence: "Strinto porcino" and its offspring "Sangiovese", "Mantonico bianco" and "Aglianico" mainly as founder varieties of South-Western Italy (IT-SW); Italian Adriatic Coast (IT-AC); and Central Italy with most varieties being offsprings of "Visparola", "Garganega" and "Bombino bianco"; "Termarina (Sciaccarello)" "Orsolina" and "Uva Tosca" as the main varieties of North-Western Italy (IT-NW) and Central Italy. The pedigree reconstruction by full-sib and second-degree relationships highlighted the key role of some cultivars, and, in particular, the centrality of "Visparola" in the origin of Italian germplasm appeared clear. An hypothetical migration of this variety within the Italian Peninsula from South to North along the eastern side, as well as of "Sangiovese" from South to Central Italy along the Western side might be supposed. Moreover, it was also highlighted that, among the main founders of muscat varieties, "Moscato bianco" and "Zibibbo (Muscat of Alexandria)" have spread over the whole Italy, with a high contribution by the former to germplasm of the North-Western of the peninsula. [ABSTRACT FROM AUTHOR]

Grapevine cultivation is being afflicted, as for many other crops, by environmental changes. Indeed, high temperatures occurring during growth may advance the date of phenological stages changing climate conditions over ripening and thus negatively affecting grape and wine quality. In particular, starting of veraison, that is the onset of the berry ripening process, and its laps of time from flowering are variable among the different varieties. Therefore, dissection of genetic determinants driving the phenological stages of flowering, veraison, as well as the interval among these, represents an interesting target in the contest of adapting grape varieties to changing environmental conditions. This has been previously enquired by QTL studies conducted in bi-parental populations. By using large diversity panels, Genome Wide Association Study (GWAS) provides a further promising approach for mapping of these traits and associated variants. To this aim, starting from a panel of more than 600 cultivars grown in the large germplasm collection of CREA-VE in Susegana (Treviso, Italy) a core of 132 genotypes representative of the genetic diversity of the whole panel was pulled out, based on genotypic data at 45 SSR markers. Using this core we have conducted a GWAS to identify loci linked to the extension of the interval between flowering and veraison times. Phenotypic data, collected over a period of 11 years, were managed together with GrapeReSeq Vitis 18K SNPChip genotyping data and bioinformatic analysis was conducted, with 3 different softwares. We identified a list of SNPs significantly associated to the phenotype by at least one of these softwares among which some were confirmed by more softwares. Alternative strategies for SNP validation were implemented, either based on further available SNP data in public repositories or on direct Sanger sequencing of some of the associated SNPs in genotypes with extreme behaviors (48 selected samples with long and 48 selected samples with short flowering-veraison interval). Potential candidate genes in the associated regions were also identified. All togheter these results provide useful clues for the flowering-veraison interval genetic regulation and for the molecular breeding in Vitis vinifera. [ABSTRACT FROM AUTHOR]

Grapevine cultivar identification is based mainly on two complementary methodologies: microsatellite (simple sequence repeat (SSR)) DNA analysis and traditional ampelography. Here, we report a direct multiplex PCR approach that allows the simultaneous amplification of 11 SSR loci from crude samples, i.e. bypassing DNA extraction, by using an engineered DNA polymerase improved to tolerate plant PCR inhibitors. Many different plant tissues were successfully amplified: leaf, root, wood, berry flesh and skin, stalk and must, from wine and table grape varieties, and rootstocks. The direct multiplex PCR that we propose is quicker and cheaper than the methodologies used until now, and provides accurate results. Thus, SSR DNA analysis becomes economically more accessible to a larger number of potential users in addition to research institutes. [ABSTRACT FROM AUTHOR]