FINGERPRINTING OF ON-FARM CONSERVED LOCAL TUNISIAN ORANGE CULTIVARS (CITRUS SINENSIS (L.) OSBECK) USING MICROSATELLITE MARKERS

This study aims to illustrate the diversity among local orange genotypes. Collecting missions targeting the traditional culture areas were organized by the National Gene Bank. Twenty-five cultivars have been screened, some of them have not yet been included in established orange collections. A powerful set of seven SSR Primer pairs was used to indentify forty-four alleles and forty-four genotypes. Polymorphic information content varies from 0.55 to 0.78 with an average of 0.66. Some mislabeling cases such as synonymy and homonymy have been clarified and genetic relationships among cultivars based on genetic distances have been revealed showing two major clusters. Finally, on the basis of multilocus genotyping, an identification key was established to unambiguously distinguish 23 well-defined genotypes (resolving a power of 92%).