Application d'une méthode d'électrophorèse pour la caractérisation et la reconnaissance des porte-greffe

L'étude par électrophorèse (gel d'amidon) de la glucose-phosphate-isomérase (GPI, EC 5.3.1.9) sur des extraits obtenus à partir des jeunes racines ou de sarments aoûtes a montré que ce type de matériel végétal pouvait être utilise en vue de l'identification des porte-greffe. Pour les racines, les meilleurs résultats ont été obtenus à partir de plants dont le feuillage était en bon état et en début de phase de croissance. L'utilisation de sarments s'est révelée en définitive plus facile et plus intéressante au niveau de la realisation des extraits et de la netteté des séparations. La variabilité observée pour le système enzymatique GPI-2 sur les trente porte-greffe autorisés en France s'avère interéssante dans une optique taxonomique et la stabilité des résultats a été confirmée. Neuf phénotypes différents (dont trois non signales jusqu'à présent) ont été mis en évidence permettant de caractériser et de reconnaître cinq porte-greffe (Fercal, .41 B, 333 E.M., 161-49 C, Vialla) et de répartir les autres en quatre groupes. L'étude d'un système complémentaire au moins devra être envisagée pour pouvoir séparer l'ensemble de ces porte-greffe.Utilization of isozyme analysis to the characterization and the identification of rootstocksIsozyme analysis by starch gel electrophoresis for glucose phosphate isomerase (GPI, EC 5.3.1.9) from roots and woody canes extracts showed that this material can be used for identification of the rootstocks. Concerning the roots the best results were obtained at the first stage of growth (during spring) when the plants were in good physiological state but this material is rather delicate. It is easier and more interesting to work with extracts of scrapings from woody canes which give good results and fair resolutions. The variability of the GPI-2 system is interesting for taxonomy and the stability of the results has been confirmed. Nine phenotypes have been found with the thirty rootstocks tested. It is possible to characterize Fercal, 41 B, 333 E.M., 161-49 C, and Vialla. The other rootstocks can be sorted in four groups. Analysis of a complementary enzyme system at least will be necessary to characterize all these rootstocks

Parentage of grapevine rootstock ‘Fercal’ finally elucidated

Using a set of 20 microsatellite markers, ‘B.C. n°1B’ (mother) and ‘31 Richter’ (father) were demonstrated to be the true parents of ‘Fercal’ rootstock. ‘333 Ecole de Montpellier’ was definitively excluded as the putative father. ‘B.C. n°1A’ and ‘B.C. n°1B’ were shown to be distinct genotypes. ‘Ugni blanc’, and not ‘Colombard’, was discovered to be the Vitis vinifera father of ‘B.C. n°1B’.

Usefulness of two SCAR markers for marker-assisted selection of seedless grapevine cultivars

A PCR-specific marker, SCP18, was developed from a RAPD marker linked to a major locus involved in seedlessness, sdI. A preliminary study of the usefulness of SCP18 and SCC8 (a marker linked to sdI previously developed by LAHOGUE et al. 1998) for the marker assisted selection of seedless varieties was realized using various strategies: a posteriori test in seedless x seedless and seeded x seeded progenies and test of their allelic diversity in a set of 81 seedless and seeded varieties. In contrast to SCP18, SSC8 was found to be a useful marker at least in the seedless x seedless progenies and to show a good linkage disequilibrium with seedlessness in our set of varieties

Distribution des principaux caractères phénologiques, agronomiques et technologiques chez Vitis vinifera L.

Dans la collection de vignes du Domaine de Vassal (INRA, France), l'espèce Vitis vinifera L. est représentée par 5311 introductions, soit 2236 cépages répertoriés et 1090 introductions en cours d'étude.Après description et identification, le potentiel viticole des cépages est évalué. Ces données, recueillies depuis plus de 40 ans, sont maintenant rassemblees dans une banque de données informatisée. Il est ainsi possible de calculer la répartition des principaux caractères sur un grand nombre de cépages (2236). Les génotypes analysés étant d'origines trés diverses, on peut considérer cet échantillon comme une des meilleures représentations disponibles de Vitis vinifera L.Les distributions, moyennes, valeurs modales et extrêmes sont présentées pour les caractères suivants: dates de débourrement et de maturité, port et fertilité, poids moyen des baies et des grappes. La connaissance de la répartition de ces caractères est très utile pour estimer la potentialité des semis , déterminer les cépages "extrêmes" susceptibles d'être utilisés dans des programmes d'amélioration et mieux apprécier Vitis vinifera L.Distribution of the main phenological, agronomical and technical characters of Vitis vinifera L.In the grapevine collection of the ''Domaine de Vassal'' (INRA, France) 5311 accessions belong to Vitis vinifera L. That represents 2236 varieties and 1090 accessions which are still in process of being studied. After being described and identified, the viticultural performances of the varieties are evaluated. These data have been collected since 40 years and are now registred and joined together in a computerized data bank. So, it is possible to calculate distributions and repartitions for the most important characters of a great number of varieties (2236). The origins of these varieties are very diversified and therefore this large sample can be considered like one of the best available representations of Vitis vinifera L. The distribution, average, modal, minimum and maximum values of the following characters are presented: date of budburst, date of maturity, shoot habit, fertility, mean berry weight and mean bunch weight. The knowledge of the repartition of these characters is very useful to estimate the potentiality of seedlings and to determine the ''extreme'' varieties which could be used in different programs of grape improvement. It supplies also a contribution to a better knowledge of Vitis vinifera L

Comparative agronomical, phenological and molecular analyses between the grape variety 'Moscato branco' and accessions of Brazilian and French grape germplasm banks.

Resumo

Genetic clustering and parentage analysis of Western Balkan grapevines (Vitis vinifera L.)

A total of 90 grapevine samples collected in five countries of the Western Balkan region were evaluated for trueness-to-type and kinship relations based on comparative analysis with 1,130 grapevine genotypes held at the INRA "Domaine de Vassal" French Grape Germplasm Repository, using 14 microsatellite markers. In the context of the comparative analysis, twenty-four synonyms/counterparts and the putative parents for twelve Balkan accessions were identified. We discovered five pairs of homonyms, subsequently confirming the identity or parentage of three of them. Some of the examined accessions were identified either on the basis of the genotypes found in the literature, or through parentage relationships revealed in this study. For the remaining fifty accessions we were unable to establish either their pedigree or to identify them on the basis of SSR profiles available elsewhere. Finally, the Balkan genotypes that were not well classified by synonymy or parentage analysis were further studied with a Principal Coordinate Analysis to reveal genetic clustering within larger datasets of genotypes. The graphical display of the individual and group distances showed that about forty accessions (85 %) are structured within a group of Balkan and Eastern Europe genotypes and only a minor proportion resulted in admixed population assignment

The European Vitis Database (www.eu-vitis.de) – a technical innovation through an online uploading and interactive modification system

The objective of the European Vitis Database is to safeguard and enhance germplasm by monitoring its preservation. Two issues are strongly related to that purpose: (1) participation of collections covering almost all grape biodiversity and (2) assessment of accessions trueness to type. In the scope of the European project GrapeGen06 efforts have been made towards both objectives. The 35 participating grape germplasm repositories are found between the Iberian Peninsula and Transcaucasia, thus covering a broad range of grape diversity. Altogether they maintain 32,410 accessions. However with respect to biodiversity, gaps are still evident and further collections need to be included and trueness to type assessment absolutely needs to be pursued to organize duplication of endangered genotypes. Within the GrapeGen06 project focus was laid on the establishment of a database conferring the collection holders a high degree of responsibility and independence. Hence for the first time in a European Central Crop Database an on-line uploading application and an interactive modification system for data administration was implemented. These innovations disburden the database manager and offer the curators of collections more flexibility. Prerequisites for data import, descriptors applied, access levels, database contents, uploading, export and search functions are described

Transposable Elements Are a Major Cause of Somatic Polymorphism in Vitis vinifera L.

Through multiple vegetative propagation cycles, clones accumulate mutations in somatic cells that are at the origin of clonal phenotypic diversity in grape. Clonal diversity provided clones such as Cabernet-Sauvignon N°470, Chardonnay N° 548 and Pinot noir N° 777 which all produce wines of superior quality. The economic impact of clonal selection is therefore very high: since approx. 95% of the grapevines produced in French nurseries originate from the French clonal selection. In this study we provide the first broad description of polymorphism in different clones of a single grapevine cultivar, Pinot noir, in the context of vegetative propagation. Genome sequencing was performed using 454 GS-FLX methodology without a priori, in order to identify and quantify for the first time molecular polymorphisms responsible for clonal variability in grapevine. New generation sequencing (NGS) was used to compare a large portion of the genome of three Pinot noir clones selected for their phenotypic differences. Reads obtained with NGS and the sequence of Pinot noir ENTAV-INRA® 115 sequenced by Velasco et al., were aligned on the PN40024 reference sequence. We then searched for molecular polymorphism between clones. Three types of polymorphism (SNPs, Indels, mobile elements) were found but insertion polymorphism generated by mobile elements of many families displayed the highest mutational event with respect to clonal variation. Mobile elements inducing insertion polymorphism in the genome of Pinot noir were identified and classified and a list is presented in this study as potential markers for the study of clonal variation. Among these, the dynamic of four mobile elements with a high polymorphism level were analyzed and insertion polymorphism was confirmed in all the Pinot clones registered in France

Genetic diversity, linkage disequilibrium and power of a large grapevine (Vitis vinifera L) diversity panel newly designed for association studies

UMR-AGAP Equipe DAVV (Diversité, adaptation et amélioration de la vigne) ; équipe ID (Intégration de Données)International audienceAbstractBackgroundAs for many crops, new high-quality grapevine varieties requiring less pesticide and adapted to climate change are needed. In perennial species, breeding is a long process which can be speeded up by gaining knowledge about quantitative trait loci linked to agronomic traits variation. However, due to the long juvenile period of these species, establishing numerous highly recombinant populations for high resolution mapping is both costly and time-consuming. Genome wide association studies in germplasm panels is an alternative method of choice, since it allows identifying the main quantitative trait loci with high resolution by exploiting past recombination events between cultivars. Such studies require adequate panel design to represent most of the available genetic and phenotypic diversity. Assessing linkage disequilibrium extent and panel power is also needed to determine the marker density required for association studies.ResultsStarting from the largest grapevine collection worldwide maintained in Vassal (France), we designed a diversity panel of 279 cultivars with limited relatedness, reflecting the low structuration in three genetic pools resulting from different uses (table vs wine) and geographical origin (East vs West), and including the major founders of modern cultivars. With 20 simple sequence repeat markers and five quantitative traits, we showed that our panel adequately captured most of the genetic and phenotypic diversity existing within the entire Vassal collection. To assess linkage disequilibrium extent and panel power, we genotyped single nucleotide polymorphisms: 372 over four genomic regions and 129 distributed over the whole genome. Linkage disequilibrium, measured by correlation corrected for kinship, reached 0.2 for a physical distance between 9 and 458 Kb depending on genetic pool and genomic region, with varying size of linkage disequilibrium blocks. This panel achieved reasonable power to detect associations between traits with high broad-sense heritability (> 0.7) and causal loci with intermediate allelic frequency and strong effect (explaining > 10 % of total variance).ConclusionsOur association panel constitutes a new, highly valuable resource for genetic association studies in grapevine, and deserves dissemination to diverse field and greenhouse trials to gain more insight into the genetic control of many agronomic traits and their interaction with the environment