Genetic diversity of the Turkish watermelon genetic resources was evaluated using different Citrullus species, wild relatives, foreign landraces, open pollinated (OP) and commercial hybrid cultivars by RAPD markers. The germplasm was consisted of 303 accessions collected from various geographical regions. Twenty-two of 35 RAPD primers generated a total of 241 reproducible bands, 146 (60.6%) of which were polymorphic. Based on the RAPD data the genetic similarity coefficients were calculated and the dendrogram was constructed using UPGMA (Unweighted pair-group method with arithmetic average). Cluster analysis of the 303 accessions employing RAPD data resulted in a multi-branched dendrogram indicating that most of the Turkish accessions belonging to var. lanatus of Citrullus lanatus (Thunb.) Matsum et Nakai were grouped together. Accessions of different Citrullus species and Praecitrullus fistulosus (Stocks) Pangalo formed distant clusters from C. lanatus var. lanatus. Among 303 accessions, a subset of 56 accessions was selected representing different groups and a second dendrogram was constructed. The genetic similarity coefficients (GS) within the Turkish accessions were ranged from 0.76 to 1.00 with 0.94 average indicating that they are closely related. Taken together, our results indicated that low genetic variability exist among the watermelon genetic resources collected from Turkey contrary to their remarkable phenotypic diversity.
Cyclamen sp. occupies a wide swathe of habitats across Turkey. Ten wild Cyclamen species grow naturally in Turkey, some being endemic. Due to this genetic variation, wild Cyclamen sp. with traits such as flower shape and colour, leaf shape and colour and disease resistance make these species important for cyclamen breeders. In this study, the potential of somatic embryogenesis from different explants (ovules, divided ovary parts, leaves and petiole segments) of 15 separate genotypes from one wild species (Cyclamen persicum Mill.) was studied. Explants were cultured on medium containing half-strength Murashige and Skoog macro- and micro-elements and 2.0 mg l−1 2,4-dichlorophenoxyacetic acid and 0.8 mg l−1 6-(γ,γ-dimethylallylamino) purine for inducing embryogenic callus. Embryogenic potential differed significantly between explants and genotypes. Although callus was most prolific from petiole explants, somatic embryos formed most efficiently on ovary explants. The ability of petiole, ovary, ovule and leaf explants, when averaged for the 15 genotypes, to form callus, was 34.3, 30.16, 26.6 and 15.6%, respectively while the percentages of somatic embryos formed were 11.3, 8.00, 4.16 and 2.83% of ovary, petiole, leaf and ovule explants, respectively.