Characterization and identification of the main Spanish and Italian olive cultivars by simple-sequence-repeat markers

Nine simple-sequence-repeat (SSR) primer pairs were assayed in 35 Spanish and Italian olive cultivars of commercial interest. All microsatellites were polymorphic, showing 5 to 13 alleles per locus (7.5 alleles per locus on average). The frequency of each alleles was generally low, with most of the alleles present at one or two cultivars. Heterozigosity ranged from 0.15 to 0.95; the discrimination power (PD) ranged from 0.30 to 0.93 (mean 0.79). The set of microsatellites analyzed discriminated all cultivars investigated. The combination of only three SSR primer pairs-UDO99-009+UDO99-043+UDO99-14-made possible the identification of all cultivars; included in the study. Cluster analysis did not find differences between Spanish and Italian cultivars, but most of the cultivars; from southern and central Spain grouped together. Hence, microsatellites markers are recommended for olive fingerprinting to generate a database for olive cultivar identification.