Thirty-three grapevine varieties from Slovenia were genotyped at 21 microsatellite loci in order accurately to identify varieties and to evaluate their synonyms and homonyms, including varieties cultivated in neighbour countries. Among Slovenian varieties some previously assumed synonyms were confirmed and some new ones were discovered: ‘Poljšakica Drnovk’ = ‘Istrska Malvazija’, ‘Pikolit Italy’ = ‘Pikolit Vienna’, ‘Vitovska grganja’ = ‘Racuk’ and ‘Prosecco’ = ‘Glera’ = ‘Števerjana’. Types of Zelen (‘Zelen Pokov’, ‘Zelen 66’ and ‘Zelen 2.4’) were distinct at several microsatellite loci so can only be considered to be homonyms. Comparison of ‘Vitovska grganja’ from Slovenia with ‘Vitouska’ from Italy also showed dissimilarities at the majority of the analysed loci.
Additional 38 costal Slovenian grapevines were genotyped by using 11 SSR markers that have been shown to be highly polymorphic in European Vitis resources. Combining those data with previous study, 49 unique genotypes were identified within the varieties currently cultivated in the Slovenian Primorje region. These genotypes were further compared to 161 cultivars from 8 European countries in order to assess their genetic relationships. A high level of genetic diversity among Slovenian grapevines was revealed and some unknown relationships were discovered. Identity analyses revealed 11 groups of synonyms among Slovenian varieties and three pairs between a Slovenian variety and a variety from other countries. Several groups of Slovenian varieties with similar names resulted in different SSR profiles. The genetic distances between varieties used in Slovenia and the most popular cultivars used in other European countries revealed the closest relationship with Croatian varieties and the most distant with French varieties.
Microsatellite inferred genetic diversity and structure of Western Balkan grapevines (Vitis vinifera L.) performed in the frame of SEE-ERA net project Vitis-WBC (Towards the preservation of autochthonous grapevine (Vitis vinifera L.) varieties in Western Balkan Countries") - vitis.atcglabs.com
A collection of 196 grapevine samples from five countries of the Western Balkan region, representing local and traditional cultivars, was genotyped with 22 SSR markers. Identity analysis revealed 138 unique genotypes, which were further used for diversity assessment. Diversity statistic values were in a range allowing confirmation of the robustness of the overall analysis. The average number of alleles per locus detected in the set of analysed grapevines was 11 ± 3.53, ranging from 6 to 21. The overall low probability of obtaining identical genotypes shown in this study implies an even distribution of alleles within the analyzed set of grapevines and a sufficient number of loci. On the basis of the discriminatory power of each SSR, a set of five markers (VVMD5, VVMD7, VVMD28, VChr3a and VChr8b) was determined as sufficient for high-throughput discrimination of the target cultivars. A core collection covering the entire genetic diversity resulted in a set of 60 genotypes out of 138, approximately 50% from each region. Structure clustering of Balkan and West European cultivars resulted in four well distinct groups. The lowest level of admixed genotypes was assigned for BiH (61%) and the highest for Serbian (87%) grapevines. In terms of grape use, the grapevine cultivars were divided into three groups, of which only one group was intermixed, with half wine and half table grapes. The highest genetic distance (0.22) was discovered between Slovenian and Macedonian cultivars, while the lowest (0.09) was between Slovenian and Serbian cultivars. Macedonian cultivars were genetically most distant from the others (0.17).