Comparative study of microsatellite profiles of DNA from oil and leaves of two Tunisian olive cultivars

The potential of microsatellites in traceability of Tunisian oils was assessed by comparison of the genetic profile for six SSR markers of DNA extracted from oil and leaves of the two Tunisian major olive cultivars: Chemlali and Chetoui. Different protocols of DNA extraction from oil were tested and compared and we found that the most reproducible protocol in terms of successful microsatellites amplification was the Qiagen QIAamp DNA Stool extraction Kit, which we slightly modified. After amplification and automatic genotyping of six SSRs, it has been shown that the pattern of the DNA purified from a monovarietal oil did not correspond exactly to the profile of the same cultivar leaves' DNA. In fact, we found evidence for the presence in the oil of alleles originating from the pollinators, which are present in the genome of the seed embryo. These alleles appear as minor peaks and could be easily distinguished from the mother tree's alleles, so they do not interfere with oil traceability.