Development of molecular tools for characterization and genetic diversity analysis in Tunisian fig (Ficus carica) cultivars.

Fig, Ficus carica L., is a useful genetic resource for commercial cultivation. In this study, RAPD (60), ISSR (48), RAMPO (63), and SSR (34) markers were compared to detect polymorphism and to establish genetic relationships among Tunisian fig tree cultivars. The statistical procedures conducted on the combined data show considerable genetic diversity, and the tested markers discriminated all fig genotypes studied. The identification key established on the basis of SSR permitted the unambiguous discrimination of cultivars and confirmed the reliability of SSR for fingerprinting fig genotypes. The study findings are discussed in relation to the establishment of a national reference collection that will aid in the conservation of Tunisian fig resources.

Genetic diversity of different Tunisian fig (Ficuscarica L.) collections revealed by RAPD fingerprints.

The genetic diversity in Tunisian fig (Ficus carica L.) was studied using RAPD markers. Thirty-five fig cultivars originating from diverse geographical areas and belonging to three collections were analysed. Random decamer primers were screened to assess their ability to detect polymorphisms in this crop. Forty-four RAPD markers were revealed and used to survey the genetic diversity and to detect cases of mislabelling. As a result, considerable genetic diversity was detected among the studied F. carica accessions. The relationships among the 35 varieties were studied by cluster analysis. The dendrogram showed two main groups composed of cultivars with similar geographic origin. Moreover, the male accessions (caprifigs) were clustered indistinctively within the female ones, suggesting a narrow genetic diversity among these accessions. Our data proved that RAPD markers are useful for germplasm discrimination as well as for investigation of patterns of variation in fig. Since this designed procedure has permitted to establish a molecular database of the reference collections, the opportunity of this study is discussed in relation to the improvement and rational management of fig germplasm.

Genetic diversity of Tunisian date palms (Phoenixdactylifera L.) revealed by nuclear microsatellite polymprohism.

Fourteen microsatellite loci of Phoenix dactylifera were targeted to examine the genetic diversity in Tunisian date-palms germplasm. They showed a high level of polymorphism in 49 accessions from three main oases with little geographic structure within Tunisia. The microsatellite data agrees with previous analyses of Tunisian germplasm using other molecular markers. 100% of local date-palms accessions were successfully fingerprinted and easily distinguished by the help of only three loci. The possibility of using microsatellites for large scale molecular labelling of offshoots and in vitro plantlets and their implication in the plant material certification is discussed.