Amelia Salimonti

A consensus list of microsatellite markers for olive genotyping

Cultivar identification is a primary concern for olive growers, breeders, and scientists. This study was aimed at examining the SSR markers retrieved from the literature and currently used in olive study, in order to select those most effective in characterizing the olive accessions and to make possible the comparison of data obtained by different laboratories. Olive microsatellite profiles were assessed by four independent laboratories, which analyzed 37 pre-selected SSR loci on a set of 21 cultivars. These SSR markers were initially tested for their reproducibility, power of discrimination and number of amplified loci/alleles. Independent segregation was tested for each pair of SSRs in a controlled cross and the allelic error rate was quantified. Some of them were finally selected as the most informative and reliable. Most of the alleles were sequenced and their sizes were determined. Profiles of the reference cultivars and a list of alleles with their sizes obtained by sequencing are reported. Several genetic parameters have been analysed on a larger set of cultivars allowing for a deeper characterization of the selected loci. Results of this study provide a list of recommended markers and protocols for olive genotyping as well as the allelic profile of a set of reference cultivars that would be useful for the establishment of a universal database of olive accessions.

Microsatellite markers for identification of a group of italian olive accessions

Cultivar characterization for fruit trees certification requires fast, efficient and reliable techniques. Microsatellite markers (SSR) were used in the molecular characterization of 23 genotypes of Olea europaea subsp europaea. The DNA from the olive cultivars was analyzed using nine pre-selected SSR primers (GAPU59, GAPU71A, GAPU71B, GAPU103A, UDO99-01, UDO99-12, UDO99-28 and UDO99-39) and revealed 29 alleles, which allowed each genotype to be identified. In the dendrogram, the nine primers allowed the 23 olive genotypes to be grouped into subgroups corresponding to the same cultivar denominations. SSR markers proved to be efficient and reliable for the molecular characterization of Italian olive cultivars.

Molecular Characterization of Italian Olive Cultivars by Microsatellite Markers.

Olive (Olea europaea L.) is a very important oil-producing crop in the Mediterranean area. Despite the long cultivation history and the great social-economic interest of the olive tree, its germplasm is today poorly characterized on the whole. Indeed, elaiographical and biometrical studies are surprisingly insufficient to well address its management and preservation. In addition, reliable molecular standardized methods in order to elucidate the potential occurrence of homonyms (one denomination for several genotypes) or synonyms (one genotype with several denominations) are needed to eliminate ambiguities in variety identification. Genetic diversity studies using microsatellite analysis were carried out in a set of 100 Italian olive (Olea europaea L.) cultivars (14 cvs from Abruzzo region, 9 cvs from Basilicata, 7 cvs from Calabria, 2 cvs from Campania, 4 cvs from Lazio, 1 cv from Liguria, 12 cvs from Molise, 12 cvs from Apulia, 29 cvs from Sicilia and 10 cvs from Toscana region). Samples of olive leaves were harvested from plants growing in the olive germplasm collection of the Consiglio per la Ricerca e Sperimentazione in Agricoltura (C.R.A.) – Istituto Sperimentale per l’Olivicoltura (ISOl) of Rende (CS), Italy. All microsatellites were polymorphic. A total of 52 alleles over nine loci were observed, ranging from 2.0 at UDO01 to 11.0 alleles at UDO39, with a mean of 5.8 alleles per locus. The expected heterozygosity ranged from 0.39 at UDO01 to 0.79 at UDO39 and the discrimination power varied from 0.40 at UDO01 to 0.89 GAPU103A. The results of alleles identification were then used to create a qualitative data matrix of presence (1) and absence (0) that was processed using NTSYS-PC software. Pairwise similarities between cultivars were calculated using Dice coefficient for qualitative data. The resulting similarity matrix was used to construct a dendrogram by means of the UPGMA (unweighted pairgroup method with arithmetical averages) algorithm. The following three presumable synonyms were detected: 1‘Filare’ and ‘Grossa di Venafro’, 2‘Giarraffa’ and ‘Pizzo di Corvo’ 3‘Frantoio’ and ‘Ogliarola barese’. Therefore, synonyms characterisation is very important to avoid genotype redundancy in order to maximise genetic diversity in Italian olive germplasm collection. This study showed that the use of molecular markers like SSRs is very useful to build a data base available for variety analysis and for olive germplasm collection management.

Traceability of “Tuscan PGI” Extra Virgin Olive Oils by 1H NMR Metabolic Profiles Collection and Analysis

According to Coldiretti, Italy still continues to hold the European Quality record in extra virgin olive oils with origin designation and protected geographical indication (PDO and PGI). To date, 46 Italian brands are recognized by the European Union: 42 PDO and 4 PGI (Tuscan PGI, Calabria PGI; Tuscia PGI and PGI Sicily). Specific regulations, introduced for these quality marks, include the designation of both the geographical areas and the plant varieties contributing to the composition of the olive oil. However, the PDO and PGI assessment procedures are currently based essentially on farmer declarations. Tuscan PGI extra virgin olive oil is one of the best known Italian trademarks around the world. Tuscan PGI varietal platform is rather wide including 31 specific olive cultivars which should account for at least 95% of the product. On the other hand, while the characteristics of other popular Italian extra virgin olive oils (EVOOs) cultivars from specific geographical areas have been extensively studied (such as those of Coratina based blends from Apulia), little is still known about Tuscan PGI EVOO constituents. In this work, we performed, for the first time, a large-scale analysis of Tuscan PGI monocultivar olive oils by 1H NMR spectroscopy and multivariate statistical analyses (MVA). After genetic characterization of 217 leaf samples from 24 selected geographical areas, distributed all over the Tuscany, a number of 202 micro-milled oil samples including 10 PGI cultivars, was studied. The results of the present work confirmed the need of monocultivar genetically certified EVOO samples for the construction of 1H-NMR-metabolic profiles databases suitable for cultivar and/or geographical origin assessment. Such specific PGI EVOOs databases could be profitably used to justify the high added value of the product and the sustainability of the related supply chain.