Genetic variability in wild cardoon (Cynara cardunculus L. var.sylvestris) revealed by SSR markers and morphological traits

This research aims at characterizing germplasm diversity of wild cardoon (Cynara cardunculus var.sylvestris) for future breeding. Six populations were identified in in the north of Tunisia and 20 individ-uals per population were evaluated using UPOV descriptors, and a large variability was revealed betweenpopulations for their leaf characteristics. The genetic diversity was also assessed using SSR markers atseventeen loci, which were all polymorphic, and a high genetic variation was found out. A low differenti-ation (Fst = 0.104) coupled with a high level of gene flow (Nm = 2.25) were observed among populations.Only 10.4% of total genetic variability is shared between populations in comparison to 89.6% within pop-ulation. Both morphological and molecular characterization showed that population grouping was notclearly related to their geographical distribution and this could be the result of the gene flow betweenregions. These results highlight a high level of genetic variation in Tunisian wild cardoon germplasm,which represents an interesting material to be conserved and exploited in breeding programs ofartichoke.