Identification of mildew resistance in wild and cultivated Central Asian grape germplasm

BACKGROUND: Cultivated grapevines, Vitis vinifera subsp. sativa, evolved from their wild relative, V. vinifera subsp. sylvestris. They were domesticated in Central Asia in the absence of the powdery mildew fungus, Erysiphe necator, which is thought to have originated in North America. However, powdery mildew resistance has previously been discovered in two Central Asian cultivars and in Chinese Vitis species. RESULTS: A set of 380 unique genotypes were evaluated with data generated from 34 simple sequence repeat (SSR) markers. The set included 306 V. vinifera cultivars, 40 accessions of V. vinifera subsp. sylvestris, and 34 accessions of Vitis species from northern Pakistan, Afghanistan and China. Based on the presence of four SSR alleles previously identified as linked to the powdery mildew resistance locus, Ren1, 10 new mildew resistant genotypes were identified in the test set: eight were V. vinifera cultivars and two were V. vinifera subsp. sylvestris based on flower and seed morphology. Sequence comparison of a 620 bp region that includes the Ren1-linked allele (143 bp) of the co-segregating SSR marker SC8-0071-014, revealed that the ten newly identified genotypes have sequences that are essentially identical to the previously identified mildew resistant V. vinifera cultivars: ‘Kishmish vatkana’ and ‘Karadzhandal’. Kinship analysis determined that three of the newly identified powdery mildew resistant accessions had a relationship with ‘Kishmish vatkana’ and ‘Karadzhandal’, and that six were not related to any other accession in this study set. Clustering procedures assigned accessions into three groups: 1) Chinese species; 2) a mixed group of cultivated and wild V. vinifera; and 3) table grape cultivars, including nine of the powdery mildew resistant accessions. Gene flow was detected among the groups. CONCLUSIONS: This study provides evidence that powdery mildew resistance is present in V. vinifera subsp. sylvestris, the dioecious wild progenitor of the cultivated grape. Four first-degree parent progeny relationships were discovered among the hermaphroditic powdery mildew resistant cultivars, supporting the existence of intentional grape breeding efforts. Although several Chinese grape species are resistant to powdery mildew, no direct genetic link to the resistance found in V. vinifera could be established

New stable QTLs for berry weight do not colocalize with QTLs for seed traits in cultivated grapevine (Vitis vinifera L.)

International audienceBACKGROUND: In grapevine, as in other fruit crops, fruit size and seed content are key components of yield and quality; however, very few Quantitative Trait Loci (QTLs) for berry weight and seed content (number, weight, and dry matter percentage) have been discovered so far. To identify new stable QTLs for marker-assisted selection and candidate gene identification, we performed simultaneous QTL detection in four mapping populations (seeded or seedless) with various genetic backgrounds. RESULTS: For berry weight, we identified five new QTLs, on linkage groups (LGs) 1, 8, 11, 17 and 18, in addition to the known major QTL on LG 18. The QTL with the largest effect explained up to 31% of total variance and was found in two genetically distant populations on LG 17, where it colocalized with a published putative domestication locus. For seed traits, besides the major QTLs on LG 18 previously reported, we found four new QTLs explaining up to 51% of total variance, on LGs 4, 5, 12 and 14. The previously published QTL for seed number on LG 2 was found related in fact to sex. We found colocalizations between seed and berry weight QTLs only for the major QTL on LG 18 in a seedless background, and on LGs 1 and 13 in a seeded background. Candidate genes belonging to the cell number regulator CNR or cytochrome P450 families were found under the berry weight QTLs on LGs 1, 8, and 17. The involvement of these gene families in fruit weight was first described in tomato using a QTL-cloning approach. Several other interesting candidate genes related to cell wall modifications, water import, auxin and ethylene signalling, transcription control, or organ identity were also found under berry weight QTLs. CONCLUSION: We discovered a total of nine new QTLs for berry weight or seed traits in grapevine, thereby increasing more than twofold the number of reliable QTLs for these traits available for marker assisted selection or candidate gene studies. The lack of colocalization between berry and seed QTLs suggests that these traits may be partly dissociated

Pedigree ascertainment of interspecific grapevine cultivars

National audienc

Verdot (Grosse Mérille). Una antigua y rara variedad francesa, patrimonio de la viticultura chilena.

It is briefly described the various introductions of Vitis vinifera L. in Chile and its expansion in the territory, as well as the predominance of the French paradigm in its more recent development. From the beginning of the 21st century, the first steps are taken in search of a new identity, with the introduction of varieties of different origins and the rescue of smaller varieties. Among the latter, stands out Verdot or Grosse Mérille, an old and rare French variety. This variety describes its presence in Chile, some climatic requirements, phenology, ampelographic characteristics and potentiality of its wines

The kindgroup of the cultivar 'Chardonnay' revealed

International audienceDespite the importance of grapevine (Vitis vinifera L.), relatively few parentages were revealed until now because small databases were analyzed. In the present work, we developed a useful and readable routine for the analysis of large data set, integrating FaMoz software. The routine was applied to a data set consisting of 2,704 individuals of the French national INRA germplasm collection of grapevine, analyzed using 20 SSRs markers well scattered over the genome. The large-scale parentage analysis enabled the identification of several kin relationships. The kingroup of ‘Chardonnay’, one of the most celebrated international grapevine cultivars, was then revealed

Identification of grapevine accessions from Argentina introduced in the ampelographic collection of Domaine de Vassal

The study of accessions from Argentina may provide a valuable testimony on the origins of the different genetic resources and varieties which were sought and used to develop the vineyard of this country. 54 accessions introduced in the Vassal collection were analyzed using 20 microsatellite markers and ampelographic descriptors. Among them, 43 distinct varieties have been identified: 22 correspond to old traditional wine or table grape varieties from Europe and Middle East, 12 are probably varieties selected in Argentina or South America and are mostly descendants of Muscat of Alexandria and Mission, 4 are seedlings obtained in Italy, USA and Bulgaria, 2 are specific mutants and 3 are still currently original and of undetermined origin. These results highlight the links and help to trace the flows that have existed between the ancient world and Argentina. They are a particularly good example of the interest of the 2 traditional ways of multiplication which may exist for the vine, cuttings and seedlings. Some of these resources are now also highly original and rare and must be preserve

Use of chloroplast microsatellite markers as a tool to elucidate polymorphism, classification and origin of Tunisian grapevines

International audienceChloroplast microsatellite markers were used in this study to genotype 43 grapevines accessions grown in Tunisia. Size variation was observed for the three cpSSR loci, both in the sample of cultivars and in wild accessions. The seven alleles observed in the sample of cultivars for the three loci are present in wild accessions except that their distribution is different. Levels of genetic diversity obtained for the Tunisian grapevines either in wild or cultivated gene pools are high and comparable with values obtained with other studied samples of Vitis vinifera. The distribution of haplotypes within the two samples is differential. Indeed, the chlorotype A is most abundant in the wild sample, whereas the chlorotype C is majority in the sample of cultivars. Haplotypes frequencies for cultivated grapevine distinguish haplotypes B and C as the most frequent (28% and 44% respectively) and haplotypes A and D as the least frequent (16% and 12% respectively). For wild grapevines, the seven alleles combined in three haplotypes, A. C and D. The haplotype A is the most frequent (44%) in the analyzed sample of wild accessions while haplotypes C and D show a frequency of 28%. Chlorotype distribution in Tunisian cultivars is comparable with that of cultivars in the Eastern Region representing the primary centre of domestication of the species. These results agree with the higher relevance of table grape cultivars in Tunisian viticulture and support an oriental origin of a large part of autochthons cultivars. Our results agree with other studies based in nuclear and chloroplast microsatellite markers and suggest independent domestication events for V. vinifera L species. (C) 2011 Elsevier B.V. All rights reserved

Genetic diversity of ancient grape cultivars of the Crimea region

UMR AGAP équipe DAAV (Diversité, adaptation et amélioration de la vigne)International audienceA total of 76 accessions of Crimean autochthonous grape cultivars from the collection of the National Institute of Vine and Wine "Magarach" were genotyped using 22 nuclear and 3 chloroplast microsatellite loci (SSR) to characterize their genetic diversity. The total number of alleles was 238, the mean number of alleles per locus was 10.8 and the range of expected heterozygosity was 0.4-0.88. Several synonyms were identified based on the comparison of microsatellite profiles with INRA and EVD databases. Morphological, eno-carpo-logical and eno-chemical characterization of number of cultivars using BBCH scale and OIV descriptors were performed. A short synopsis of the origin and historical development of Crimean autochthonous grape cultivars is presented

Linkage disequilibrium in wild French grapevine, Vitis vinifera L. subsp silvestris

Contact: [email protected] audienceAssociation mapping based on linkage disequilibrium (LD) can provide high resolution for whole-genome mapping of genes underlying phenotypic variation. This field has received considerable attention over the last decade. We present here the first characterization of LD in wild French grapevine, Vitis vinifera L. subsp. silvestris. To assess the pattern and extent of LD, we used a sample of 85 plants from southern France and 36 microsatellite markers distributed over 5 linkage groups. LD was evaluated with independence tests and multiallelic r2, using both unphased genotypic data and reconstructed haplotypic data. LD decayed rapidly, with r2 values decreasing to 0.1 within 2.7 cM for genotypic data and within 1.4 cM for haplotypic data. Compared to the results of a previous study on cultivated grapevine subsp. sativa, where significant LD was found up to 16.8 cM, LD in subsp. silvestris was no longer significant past 1.4 cM. LD was therefore 12 times further extended in cultivated than wild grapevine, even though LD in wild grapevine seemed to extend slightly further than in wild relatives of other crops. Domestication bottlenecks and vegetative propagation are the primary factors responsible for this difference between cultivated and wild grapevine. The rapid decay of LD observed in this study seems promising for future association mapping studies of functional variation in wild V. vinifera grapevine

Verdot (Grosse Mérille). Una antigua y rara variedad francesa, patrimonio de la viticultura chilena.

International audienceIt is briefly described the various introductions of Vitis vinifera L. in Chile and its expansion in the territory, as well as the predominance of the French paradigm in its more recent development. From the beginning of the 21st century, the first steps are taken in search of a new identity, with the introduction of varieties of different origins and the rescue of smaller varieties. Among the latter, stands out Verdot or Grosse Mérille, an old and rare French variety. This variety describes its presence in Chile, some climatic requirements, phenology, ampelographic characteristics and potentiality of its wines