Grape Accessions Research Articles

Anthocyanin Composition of Several Wild Grape Accessions

This study investigated the anthocyanin composition of 21 mostly Spanish wild grapevine accessions preserved at El Encin Germoplasm Bank and selected in consideration of observed ampelographic differences and molecular characterization. Sampling was carried out in 2006, 2007, and 2008. After extraction from grape skins, total anthocyanins was determined by spectrophotometry and the anthocyanin fingerprint of grapes, based on 15 anthocyanin variables, was determined by HPLC. Total anthocyanin concentration was similar to that found in winegrape cultivars. The accessions studied showed considerable variability in their anthocyanin fingerprints and it was possible to distinguish several groups, similar to previous reports on the anthocyanin fingerprint of winegrapes. The anthocyanin composition of wild grapevine accessions was similar to that of cultivated grapes. Nevertheless, the presence of wild accessions with anthocyanin fingerprints uncommon or nonexistent in Spanish cultivated varieties suggests that the genetic variability related to anthocyanins in Spanish wild grapevine populations may be higher than that of cultivated varieties commonly considered of Spanish origin.

Phenotypic divergence among wine grap accessions in the semi-arid region of Brazil

The objective was to estimate the phenotypic divergence in wine grapes based on 11 agronomic variables. Two contrasting groups, both for white as for red grapes, were formed by principal component analysis. In white grapes, greatest divergence was observed in the accessions Baco Blanc, Campanário and Palomino. In red grapes, the most divergent were Aramon and Tannat; Castelão and Mars. The standardized Euclidean distance indicated 52.4 and 40.0% white and red grape accessions, respectively, with means exceeding the overall mean. By UPGMA, four major groups were formed for white and red grapes. Both principal component analysis and UPGMA showed that the genealogy of the accessions Petite Sirah FR and Petite Sirah RS is similar. The accessions with most divergence in the traits studied should be used to produce hybrids, as well as for selection of accessions with a view to regional wine making.

Evaluation of DNA polymorphism among cultivated and wild grapevine accessions from Azerbaijan

To estimate genetic relationships among 31 cultivated and 34 wild grape accessions originating from regions near the Caspian Sea in the Azerbaijan Republic, RAPD analysis was performed with 27 decamer primers selected from a total of 55 primers. The most discriminating primers were OPC-16, OPF-18 and OPA-17, which showed the highest values of genetic diversity (0.927, 0.914 and 0.909, respectively). The lowest values of diversity pertained to the markers OPA-1 (0.615) and V-20 (0.624). The cluster analysis representing genetic similarity among all selected samples divided the genotypes into nine separate groups at similarity index 0.508. Within the studied Azerbaijan grape populations the highest genetic diversity belonged to the population of cultivated samples originating from the Absheron peninsula, with a diversity index 0.852 and the next ranks were assigned to the wild populations originating from Nabran and Guba regions, with a diversity index 0.824 and 0.793, respectively. The lowest diversity was observed within Davachi individuals, with a diversity index 0.765. The wild population from Azerbaijan was molecularly similar to the cultivated gene pool from this area. This result supported the hypothesis that the southwest of the Caspian Sea is a region where grape was brought into culture. During the analysis a special band was observed which could be used in identifying wild and cultivated grape accessions with high or low resveratrol content. The results of this work clearly indicated that the RAPD analysis can be used to estimate genotypic similarities, genetic diversity and for clustering cultivated and wild grape accessions.

Genetic Relationships of Chinese Grape Accessions to European and American Cultivars Assessed by Microsatellite Markers

ABSTRACTA total of 45 grape accessions were used to investigate the genetic polymorphism and relationships among Chinese and other European or America grape accessions by microsatellite markers. Eighty-six alleles were detected in 9 simple sequence repeat (SSR) loci with an average of 9.6 alleles per locus. Genetic similarity ranged from 0.38 to 0.83 with an average value of 0.58. This indicated sufficient diversity among the accessions. Based on cluster analysis and principal coordinate analysis, the results showed that all accessions could be divided into three major groups and the clustering pattern was related to the classical ecogeographical grouping: occidentalis, pontica and orientalis. Those from the same ecological group could cluster preferentially in most cases into one group, suggesting the positive correlation between the cluster results and the geographical origin of the grape accessions. Wine grapes were significantly differentiated from table grapes no matter whether the accessions were from China or other countries.

Genetic structure and differentiation among grapevines (Vitis vinifera) accessions from Maghreb region

Three gene pools representative of Vitis vinifera L. subsp. vinifera (=subsp. sativa Beger) growing in the Maghreb regions (North Africa) from Tunisia (44), Algeria (31) and Morocco (18) and 16 wild grape accessions (Vitis vinifera L. subsp. sylvestris (Gmelin) Beger) from Tunisia were analysed for genetic diversity and differentiation at twenty nuclear microsatellites markers distributed throughout the 19 grape chromosomes. 203 alleles with a mean number of 10.15 alleles per locus were observed in a total of 109 accessions. Genetic diversities were high in all populations with values ranging from 0.6775 (Moroccan cultivars) to 0.7254 (Tunisian cultivars). Fst pairwise values between cultivated grapevine populations were low but found to be significantly different from zero. High Fst pairwise values were shown between wild and cultivated compartments. Two parent offspring relationships, two synonyms and two clones of the same cultivar were detected. The rate of gene flow caused by vegetative dissemination of cultivated grapevine plants was not sufficient to genetically homogenise the pools of cultivars grown in different regions. The Neighbour Joining cluster analysis showed a clear separation according to geographical origins for the cultivated grapevines gene pools and revealed a high dissimilarity between cultivated and wild grapevine. However, three cultivars (Plant d’Ouchtata 1, Plant de Tabarka 3 and Plant d’Ouchtata 3) are very close to wild accessions and may result from a hybridisation between cultivated and wild accessions. The high level of differentiation between cultivated and wild accessions indicates that the cultivated accessions do not derive directly from local wild populations but could mostly correspond to imported materials introduced from others regions during historical times or derived from crossing between them.

PHYLOGENETICS ANALYSIS OF NORTH AMERICAN NATIVE 'CYNTHIANA'/'NORTON' GRAPE CULTIVAR USING DNA MICROSATELLITE MARKERS

‘Cynthiana’/‘Norton’ is considered the best American native grape variety for fine wine with suspected to have tolerance to PD (Pierce’s disease) and proven low susceptibility to foliar and fruit disease. The variety has been very successfully grown for commercial wine production for more then a century in the eastern United States and for the past decade in Louisiana within PD zone as well. Most of the grapevine varieties in existence today are centuries old and are considered to have arisen by various means: domestication of wild vines, spontaneous crosses between wild vines and varieties, and crosses between two or more varieties. Using the methods of molecular analysis, the pedigree describing the genetic history of grape variety can be reconstructed. DNA microsatellites have proved to be the markers of choice for this purpose since they are transmitted in a codominant Mendelian manner. It is assumed that ‘Cynthiana’/‘Norton’ is originated from Vitis aestivalis, Michaux. We are investigating the phylogenetics of the ‘Cynthiana’/‘Norton’ grape via data mining in the North American grape germplasm collections, ampelographic analysis and specifically expressed in the variety microsatellite markers. We are using an already-published set of ten pairs of SSR primers designed for Vitis riparia. For the purpose developing more specific markers, ‘Norton’ publicly available expressed sequence tags (ESTs) were used to screen for SSR. Two 202 SSRs out of 2,101 ESTs were located and the promising SSR primers were synthesized for specific amplification in the targeted grape accessions. This study is designed to identify the pedigree and genetic make up of ‘Cynthiana’/‘Norton’ grape and to verify that this particular grape variety carry tolerance to Pierce’s disease and is appropriate for high quality red wine production under Florida environmental conditions.

GRAPE GENETIC RESOURCES AND RESEARCH AT THE DAVIS CALIFORNIA NATIONAL CLONAL GERMPLASM REPOSITORY

The Davis, California National Clonal Germplasm Repository (NCGR) houses most Mediterranean-adapted fruit and nut crop collections in the U.S., including grapes (Vitis). The NCGR is part of the USDA National Plant Germplasm System (NPGS). Our missions are to acquire, preserve, characterize, and distribute germ- plasm resources of our designated crops (http://www.ars.usda.gov/pwa/davis/ npgs). It is NPGS policy to distribute plant material, free of charge, to research interests around the world. The NCGR grape collection includes >2800 different accessions, including one of the world's finest Vitis species collections, -.600 V vinifera wine grape varieties, and —600 V i'inifera table grape varieties. Our sister repository in Geneva, NY houses the cold-hardy grape collection. At the Davis NCGR, genetic markers have been used intensively to assess diversit y, relatedness, and trueness to type within the collection. To date, DNA microsatellite and AFLP fingerprinting has been conducted on more than 700 NCGR grape accessions, including 366 V vinifera. Examination of genetic relationships across numerous Vitis species revealed genetic affinities roughly corresponding to taxonomic distinctions derived morphologically. Proper identifica- tion is a key concern since individual grape cultivars have been widely dispersed, with many synonyms, and often the same name used for different cultivars. Except for known or presumed bud-sports, a standard eight microsatellites have uniquely identified each genotype tested. Recent fingerprinting for V vinifera in European national collections should make it possible to verify identity of many of the J' vinifera varieties in our collection. We will complete standard fingerprinting of named cultivars in our collection by 2008.

PCR Screening forXylella fastidiosain Grape Genebank Accessions Collected in the Southeastern United States

The National Clonal Germplasm Repository (NCGR) in Davis, California (CA) maintains the United States collection of warm-climate grapes in a field genebank in Winters, CA. This collection includes numerous accessions that are highly susceptible to Pierce’s disease (PD) as well as many PD-tolerant accessions that are native to the southeastern United States. If the glassy-winged sharpshooter became established in the Winters area, then reservoirs of the PD causal agent <i>Xylella fastidiosa</i> (Xf) within the collection would provide abundant inoculum for the rapid spread of Xf throughout the genebank. Therefore, PCR screening for Xf was conducted using a primer pair that is genome sequence specific to Xf and is reported to provide a high degree of sensitivity and specificity to all Xf strains that have been tested. Basal leaf petioles were collected from 60 different accessions in the NCGR representing a broad cross section of taxa and periods of time since collection in the region where Xf is endemic. Only Chardonnay previously inoculated was found positive for presence of Xf. It is concluded that NCGR grape accessions collected as budwood in the southeastern United States, where Xf and PD are endemic, are not a significant reservoir of Xf. There appears to be no reason for removing these vines if GWSS populations become established in the area surrounding the genebank.

Characterization of Grapevine Accessions from Ukraine Using Microsatellite Markers

Forty-seven wine and table grape accessions representing cultivars widely grown in Ukraine and 28 reference accessions were genotyped at six microsatellite loci (VVS2, VVMD5, VVMD7, VVMD27, VrZAG62, and VrZAG79) in order to solve accession labeling problems among Ukrainian accessions, characterize their genetic diversity, and establish genetic relationships with other European grapevine cultivars. Genotypes were standardized to meet the requirements of the European Vitis Database. Genetic diversity (<i>H_E</i> = 0.845) and allelic richness (<i>A</i>_S = 8.09 alleles/locus/random sample of 16 individuals) were found to be higher in the Ukrainian collection than in any other geographical region, based on previously published studies on grapevine accessions. No geographic structure was identified in the total data set. However, winegrapes were significantly differentiated from table grapes and a Bayesian method detected two genetic clusters, one containing mainly table and Muscat grapes and the other mainly winegrape accessions from throughout Europe, including Ukraine. These results highlight the contribution of Muscat and European winegrapes in the breeding design of Ukrainian varieties and suggest that selection and historical and contemporary movement of germplasm are major factors shaping the structure of the grapevine gene pool. The genetically rich and diversified gene pool of Ukrainian varieties represents valuable source material for future sustainable breeding and improvement of grapevine.

A SNP transferability survey within the genus Vitis

BackgroundEfforts to sequence the genomes of different organisms continue to increase. The DNA sequence is usually decoded for one individual and its application is for the whole species. The recent sequencing of the highly heterozygous Vitis vinifera L. cultivar Pinot Noir (clone ENTAV 115) genome gave rise to several thousand polymorphisms and offers a good model to study the transferability of its degree of polymorphism to other individuals of the same species and within the genus.ResultsThis study was performed by genotyping 137 SNPs through the SNPlex™ Genotyping System (Applied Biosystems Inc.) and by comparing the SNPlex sequencing results across 35 (of the 137) regions from 69 grape accessions. A heterozygous state transferability of 31.5% across the unrelated cultivars of V. vinifera, of 18.8% across the wild forms of V. vinifera, of 2.3% among non-vinifera Vitis species, and of 0% with Muscadinia rotundifolia was found. In addition, mean allele frequencies were used to evaluate SNP informativeness and develop useful subsets of markers.ConclusionUsing SNPlex application and corroboration from the sequencing analysis, the informativeness of SNP markers from the heterozygous grape cultivar Pinot Noir was validated in V. vinifera (including cultivars and wild forms), but had a limited application for non-vinifera Vitis species where a resequencing strategy may be preferred, knowing that homology at priming sites is sufficient. This work will allow future applications such as mapping and diversity studies, accession identification and genomic-research assisted breeding within V. vinifera.

Genetic structure and differentiation in cultivated grape, Vitis vinifera L.

222 cultivated (Vitis vinifera) and 22 wild (V. vinifera ssp. sylvestris) grape accessions were analysed for genetic diversity and differentiation at eight microsatellite loci. A total of 94 alleles were detected, with extensive polymorphism among the accessions. Multivariate relationships among accessions revealed 16 genetic groups structured into three clusters, supporting the classical eco-geographic grouping of grape cultivars: occidentalis, pontica and orientalis. French cultivars appeared to be distinct and showed close affinity to the wild progenitor, ssp. sylvestris from south-western France (Pyrenees) and Tunisia, probably reflecting the origin and domestication history of many of the old wine cultivars from France. There was appreciable level of differentiation between table and wine grape cultivars, and the Muscat types were somewhat distinct within the wine grapes. Contingency chi2 analysis indicated significant heterogeneity in allele frequencies among groups at all loci. The observed heterozygosities for different groups ranged from 0.625 to 0.9 with an overall average of 0.771. Genetic relationships among groups suggested hierarchical differentiation within cultivated grape. The gene diversity analysis indicated narrow divergence among groups and that most variation was found within groups (approximately 85%). Partitioning of diversity suggested that the remaining variation is somewhat structured hierarchically at different levels of differentiation. The overall organization of genetic diversity suggests that the germplasm of cultivated grape represents a single complex gene pool and that its structure is determined by strong artificial selection and a vegetative mode of reproduction.

GENETIC CHARACTERISATION OF ITALIAN WINE GRAPE CULTIVARS BY MICROSATELLITE DNA ANALYSIS

Fifty-three red and white Vitis vinifera wine grape accessions, chosen for similarities of growing district or morphological features from central northern Italy, were selected for genetic analysis employing the six microsatellite loci VVS1, VVS2, VVS5, VVS29, VVS 16 and VVMD7. The resulting data made it possible to characterise all the accessions and to evaluate the discriminating power of the 6 microsatellite markers, three of which appear to be sufficient to separate all the varieties. The data were also employed to assess the genetic relationships among the cultivars via two distinct approaches: δ μ (delta mu) and fuzzy set similarity. The cultivar clustering shown by the fuzzy set dendrogram appears to better match the geographical distribution of the varieties.

Using Simple Sequence Repeats (SSRs) for DNA Fingerprinting Germplasm Accessions of Grape (Vitis L.) Species

The USDA-ARS Vitis genetic resources collections in Geneva, N.Y., and Davis, Calif., contain ≈3600 accessions of &gt;35 species. Accurate and unambiguous identification of these grapes is essential for efficient and effective use of this germplasm. Previous workers have successfully used polymerase chain reaction (PCR)-generated SSRs to fingerprint cultivars of the wine and table grape species, V. vinifera. Building on this work, we conducted a test of five previously characterized SSR loci on 110 accessions of 25 grape taxa (21 Vitis species and 4 hybrids) to determine if they would satisfy our need for identifying cultivars within the USDA-ARS grape collections. Scorable SSR fragments were produced with all 550 primer-accession combinations, with no null loci observed. The loci were highly polymorphic, with 16 to 38 different alleles found at a locus. Heterozygosity values ranged from 0.464 to 0.818, while gene diversity values ranged from 0.875 to 0.955. Discrimination power at a locus varied from a low of 0.947 to a high of 0.987. Combined discrimination power of all loci was effectively 1.000, with 2 chances in 100,000,000 that two sexually, independently derived grape accessions would not be distinguishable using this set of five SSR loci. Two plants in the study that had previously been classified as belonging to different grape species were shown to have identical SSR fingerprints, showing that they almost certainly possessed the same genotype. Because SSR markers are codominant and highly polymorphic and SSR loci are generally conserved across a range of related species, we strongly recommend SSRs for fingerprinting not only grape, but other clonal genetic resources collections as well.

Proposed Biochemical Descriptors for Amino Acids to Evaluate Grape Germplasm.

Amino acid profiles in juice were determined by using 259 grape germplasm including 169 cultivars, 81 breeder's lines, 5 rootstocks and 4 clones of wild species. Amino acid contents of cultivars and breeder's lines were higher than those of rootstocks and wild species. For amino acid composition, arginine (Arg), alanine (Ala) and glutamic acid (Glu) were predominant compared with asparatic acid (Asp), threonine (Thr), serine (Ser), valine (Val), methionine (Met), isoleucine (Ile), and leucine (Leu). Based on the primary amino acids, the grape accessions could be classified into the following five types: Glu, Arg, Ala, Arg+Ala and Ala+ Arg. Furthermore, to evaluate amino acid composition easi-ly, a new biochemical descriptor designated as γ ratio= [Thr+Ser+ Ala] /([Asp+Glu] + [Val + Met + Ile + Leu + Arg] ) was introduced. The variation in γ ratio is significantly associated with both use and species parentage, indicating that genetic differentiation for amino acid composition exists among grape germplasm. In addition, as the biochemical descriptor, amino acid profiles in grape germplasm were defined as 3 classes of amino acid content (3 : ?? 1.00 mmol ; 5 : 1.012.00 mmol ; 7 : 2.01 mmol ??, class interval= 1.0 mmol/100 ml equivalent), and 5 classes of γ ratio (1 : ?? 0.50 ; 3 : 0.511.00 ; 5 : 1.011.50 ; 7 : 1.512.00 ; 9 : 2.01 ??, class interval=0.5), respectively.

EVALUATION OF GRAPE GERMPLASM FOR DOWNY MILDEW RESISTANCE

Trials were established in Fayetteville, Ark., in 1993 and in 1994 to evaluate grape germplasm for downy mildew resistance. Accessions were obtained from the national grape repositories in Geneva, N.Y.; Davis, Calif.; and the Univ. of Arkansas fruit substation, Clarksville. The 1993 trial contained 26 cultivars, eight selections, and 24 Vitis species; the 1994 trial contained 37 cultivars. Each trial had four single-plant replications. Plants were rated on a scale of 0 to 5 for sporulation, chlorosis, and necrosis on 23 Aug. and 26 Sept. 1994. Fungicides were not applied to the vineyard to better determine the level of natural downy mildew resistance. The results from both trials indicated that several grape accessions showed little or no symptoms of downy mildew, which suggests these have resistance that would be beneficial to use in a breeding program.

Berry and seed characteristics associated with stenospermy in vinifera grapes

SummaryBerries from stenospermic grape accessions contain partially formed seed that are variable in size, number and texture of the inviable seed traces. Methods of detecting the stenospermic character usually require some degree of subjectivity or sensory evaluation. In this study, berry and seed trace variables were examined in 28 accessions of Vitis vinifera L. for their association with the stenospermic trait. It was shown that seed germination was an unreliable indicator of the stenospermic trait. Seeded and stenospermic grape accessions were separated most clearly on the basis of sinker frequency. Standardized procedures are given for determining the frequency of sinkers from grape accessions.