Assessing phenolic and molecular diversity of arta (Calligonum comosum L.), a wild Tunisian desert plant

Abstract

• Calligonum comosum of Polygonaceae is one of the most economically important resources of the Tunisian desert. • To better appreciate and further refine the diversity analysis, we have opted for two molecular analysis techniques, RAPD and ISSR, and one technique of biochemical analysis. • HPLC/MS screened methanol extracts of identified phenolic compounds. • Biochemical and molecular polymorphism could provide information regarding genetic background and distribution of diversity of C. comosum . • Genetic diversity help to plan an effective conservation strategy for the species. The species Calligonum comosum of Polygonaceae is one of the most economically important resources of the Tunisian desert, playing an important role in the lives of the local populace. This plant has been reported to possess various chemical constituents and many medicinal effects. A great range of genetic diversity could be seen in diverse populations of this species spread of south Tunisian. To better appreciate and further refine the diversity analysis, we have opted for two molecular analysis techniques, RAPD and ISSR, and one technique of biochemical analysis. The extent of genetic variability was estimated in a set of seven Calligonum genotypes collected in seven Tunisian arid regions using 7 RAPD (random amplified polymorphic DNA) and 7 ISSR (inter simple sequence repeats) markers. ISSR and RAPD markers revealed 67% and 72, 85% polymorphic bands, respectively. The relative efficiencies of these marker systems are compared using various parameters such as effective multiplexing ratio (EMR), marker index (MI), and the polymorphic information content (PIC). RAPD seems to be the most informative and efficient system. A significant correlation is observed between the Jaccard dissimilarity matrices based on the ISSR and RAPD markers ( r = 0.66). HPLC/MS screened methanol extracts of the seven genotypes and the identified phenolic compounds were further quantified. Significant differences were observed among the various studied genotypes regarding their phenolic compound content. The overall results showed that C.comosum is an excellent source of diverse bioactive molecules, which could be an interesting material for industrial purposes. The biochemical markers do not correlate with the ISSR and RAPD markers. These findings are important for a better understanding of the adaptive strategy of C. comosum in south Tunisia. They will be useful for conservation managers to work out an effective strategy to protect this important species.