Morphological properties and chemical composition of three Calligonum species Growing-wild in Tunisian Desert: A chemotaxonomic study

The essential oils of three wild species of Calligonum (C. azel, C. arich and C. comosum) growing in Tunisian desert were obtained by hydrodistillation and were analyzed in order to discern the differences and similarities between the volatiles chemical compositions of these species. A total of 110 compounds, which accounted for 93.95-99.68 % of the total composition of the oils, have been identified. The main constituents were viridiflorol (9.59 %) in C. azel, palmitic acid (20.06%) in C. arich and 9-Octadecenoic acid (19.76 %) in C. comosum. Morphological similarity study shows two groups: the first one contains C. azel and C. comosum and the second group is formed by C. arich. Based on their chemical composition, two chemotaxonomic groups may be established: C. azel on one hand, C. arich and C. comosum on the other hand. As a consequence, the morphological diversity of these species doesn’t reflect their chemical polymorphism.