Characterization of grapevine (Vitis vinifera L.) cultivars from northern Portugal using RAPD and microsatellite markers

Twelve grapevine cultivars from northern Portugal were characterized with RAPD and microsatellites. Nine primers were used in the RAPD analysis; 8 of the varieties showed monotypic patterns. With the 6 microsatellite loci a total of 38 alleles was obtained. Relationships among the studied varieties were observed. Both types of molecular markers have proved useful for identification. Existence of synonymies is discussed.

Molecular diversity and genetic relationships in Secale

The objective of this study was to quantify the molecular diversity and to determine the genetic relationships among Secale spp. and among cultivars of Secale cereale using RAPDs, ISSRs and sequence analysis of six exons of ScMATE1 gene. Thirteen ryes (cultivated and wild) were genotyped using 21 RAPD and 16 ISSR primers. A total of 435 markers (242 RAPDs and 193 ISSRs) were obtained, with 293 being polymorphic (146 RAPDs and 147 ISSRs). Two RAPD and nine ISSR primers generated more than 80% of polymorphism. The ISSR markers were more polymorphic and informative than RAPDs. Further, 69% of the ISSR primers selected achieved at least 70% of DNA polymorphism. The study of six exons of the ScMATE1 gene also demonstrated a high genetic variability that subsists in Secale genus. One difference observed in exon 1 sequences from S. vavilovii seems to be correlated with Al sensitivity in this species. The genetic relationships obtained using RAPDs, ISSRs and exons of ScMATE1 gene were similar. S. ancestrale, S. kuprijanovii and S. cereale were grouped in the same cluster and S. segetale was in another cluster. S. vavilovii showed evidences of not being clearly an isolate species and having great intraspecific differences

Identification of minority grapevine cultivars from Vinhos Verdes Portuguese DOC Region

The Portuguese Vinhos Verdes DOC Region retains a considerable biodiversity in grapevine varieties. Unfortunately, regional grapevine patrimony is in danger of disappearing. The present study was carried out in order to genotype, using 12 microsatellite loci, a group of 39 accessions of Vinhos Verdes DOC region, including underuse and minor varieties included in the wine list of varieties and also several unknown accessions with regional designations. The accessions analyzed were identified and grouped into 34 different genotypes, nine of them referred as new genotypes. Some new synonyms were detected, namely between Spanish and Portuguese cultivars. Misidentifications and wrong designations were also detected

Prospection and identification of grapevine varieties cultivated in north Portugal and northwest Spain

A broad prospection of grapevine plants was carried out in northwest Spain and north of Portugal during the period from 2002 to 2009. It included zones located in Galicia as well as in the provinces of León, Zamora and Salamanca in Spain and the region delimited by the right side of the Douro river and the spanish border in Portugal. A total of 669 accessions were sampled, studied and identified, both by using the six microsatellite loci included in the OIV descriptors list, plus ampelographic characters. As a result of the study a total of 53 different grapevine varieties were identified. Most of them correspond to minor varieties that are present in the zone. In many cases the same variety was detected in both countries, although denominated with different names that are synonymous. The molecular markers that were analyzed are those included in the OIV 801 to 806 descriptors, and correspond to the following loci: VVS2, VVMD5, VVMD7, VVMD27, ssrVrZAG62 and ssrVrZAG79. Allele sizes of the studied varieties are recorded. Relationships among these varieties seem to be possible. Recommended priority names for the studied varieties both in Spain and in Portugal are listed, in order to avoid misidentifications and reduce the incidence of homonymies.

Effectiveness of AFLPs and retrotransposon-based markers for the identification of portuguese grapevine cultivars and clones

Grapevine germplasm, including 38 of the main Portuguese cultivars and three foreign cultivars, Pinot Noir, Pinot Blanc and Chasselas, used as a reference, and 37 true-to-type clones from the Alvarinho, Arinto, Loureiro, Moscatel Galego Branco, Trajadura and Vinhão cultivars were studied using AFLP and three retrotransposon-based molecular techniques, IRAP, REMAP and SSAP. To study the retrotransposon-based polymorphisms, 18 primers based on the LTR sequences of Tvv1, Gret1 and Vine-1 were used. In the analysis of 41 cultivars, 517 IRAP, REMAP, AFLP and SSAP fragments were obtained, 83% of which were polymorphic. For IRAP, only the Tvv1Fa primer amplified DNA fragments. In the REMAP analysis, the Tvv1Fa-Ms14 primer combination only produced polymorphic bands, and the Vine-1 primers produced mainly ISSR fragments. The highest number of polymorphic fragments was found for AFLP. Both AFLP and SSAP showed a greater capacity for identifying clones, resulting in 15 and 9 clones identified, respectively. Together, all of the techniques allowed for the identification of 54% of the studied clones, which is an important step in solving one of the challenges that viticulture currently faces

Berry color variation in grapevine as a source of diversity

Even though it is one of the oldest perennial domesticated fruit crops in the world, grapevine (Vitis vinifera L.) cultivation today is the result of both conventional breeding practices (i.e. hybridizations adopted during the last century) and vegetative propagation. Human-assisted asexual propagation has allowed the maintenance of desired traits but has largely impacted the frequency of spontaneous somatic mutations observed in the field. Consequently, many grapevine fruit attributes to date have been artificially selected, including: fruit yield, compactness, size and composition, the latter being greatly diversified in the pursuit of altering berry skin coloration. The present review provides an overview of various aspects related to grapevine diversity, with a special emphasis on grape berry skin color variation and will discuss the current knowledge of how grape skin color variation is affected by the synthesis of phenolic compounds, particularly anthocyanins and their underlying genetic factors. We hope this knowledge will be useful in supporting the importance of the berry color trait diversity in cultivated grapevines, which is used as basis for selection during breeding programs because of its application for vine growers, winemakers and consumers

Molecular characterization of berry skin color reversion on grape somatic variants

[BACKGROUND], During grapevine domestication somatic variation has been used as a source of diversity for clonal selection. [OBJECTIVE], This work provides additional information on the molecular mechanisms responsible for berry skin color reversion on a subset of somatic variants for berry skin color never investigated before. [METHODS], The berry color locus and its surrounding genomic regionwere genetically characterized through a layer-specific approach, which has already been proven to be a successful method to decipher the molecular mechanisms responsible for color reversions on somatic variants. [RESULTS], Deletions of different extent and positions were detected among less-pigmented/unpigmented variants derived from a pigmented wild-type. These deletions affected only the inner cell layer in the less pigmented variants and both cell layers in the unpigmented variants. Regarding the pigmented variants derived from an unpigmented wild-type, only one group was distinguished by the Gret1 retrotransposon partial excision from the VvMybA1 promoter. Moreover, within this latter group, VvMybA2 showed an important role regarding the phenotypic variation, through the recovery of the functional G allele. [CONCLUSIONS], This investigation focused on the berry color locus using somatic variants for berry skin color, promotes a better understanding of the evolutionary events behind their origin and variability, opening an opportunity for their use in the genetic improvement of varieties

Genetics and expression of anthocyanin pathway genes in the major skin-pigmented Portuguese cultivar ‘Vinhão’ developing berries

‘Vinhão’ is an autochthonous Portuguese cultivar with an intense black-bluish skin color, highly appreciated due to this feature. This study aimed to give the first insights into the genetic background that may be responsible for the skin color properties of cv. ‘Vinhão’. For this purpose, the allelic composition of MYBA1 and MYBA2 genes was investigated, along with quantification of the expression levels of structural and regulatory genes involved in the anthocyanin biosynthetic pathway via qRT-PCR. The molecular characterization of MYBA1 and MYBA2 loci revealed that cv. ‘Vinhão’ is homozygous for the functional allele in both genes, corresponding to the most ancestral haplotype, which is consistent with the high colored phenotype that characterizes this cultivar. There were no differences in the DNA sequence of the MYBA1 promoter region between cv. ‘Vinhão’ and the grapevine reference genome Pinot Noir. The expression patterns of genes playing key functional roles in anthocyanin biosynthesis was analyzed in four developmental stages. The dynamics occurring throughout grape berry development revealed the involvement of these genes in the progression of key development events, mainly from veraison to mature berries. These findings provide the first molecular characterization focused on the skin color feature of cv. ‘Vinhão’ to improve our understanding of the genetics behind its intense skin pigmentation