Integrating SCoT, CBDP, and ISSR molecular markers for genetic diversity assessment and taxonomic authentication of some Asteraceae species in Egypt

Abstract Despite the few numbers of molecular investigations exploring the genetic diversity, very scarce information is available for supporting the taxonomic and anatomical investigations of Asteraceae species in Egypt. Thus, the adoption of modern DNA based marker techniques is an urgent need to dive into the taxonomic authentication, evolutionary relationship in addition to the calculation of genetic variations within and between Asteraceae species. Hence, the current study was conducted to assess the intraspecific genetic diversity and authenticate taxa at the species level among and within 20 different species of Asteraceae family. Using 19 primers combinations belonging to three different molecular marker systems namely, Start Codon Targeted (SCoT), CAAT box-derived Polymorphism (CBDP) and Inter Simple Sequence Repeats (ISSR). A total of 285 amplified DNA fragments were produced, including 273 polymorphic DNA bands, with an average of percentage of polymorphism (PPB) ranged from 91.10 to 100.00% and the average of polymorphism information content (PIC) for SCoT, CBDP, and ISSR markers were 0.349, 0.403, and 0.418 respectively. The population structure analysis suggested that the 20 Asteraceae species could be categorized into 2 or 7 or 8 genetic groups based on SCoT, CBDP, and ISSR markers datasets, respectively. Both factorial and phylogenetic analyses based on the presence or absence of the amplified bands/fragments were performed by Jaccard’s similarity coefficient. Interestingly, Unweighted pair group method with arithmetic mean (UPGMA) cluster dendrograms for all markers system) two main clusters that all subsequently divided into different subgroups of species. Surprisingly, the UPGMA dendrogram generated based on CBDP marker data was divided into main clusters only one species of Centaurea cristata L. that collected from AGERI was clustered as a unique and main cluster separately while the remaining 19 species of Asteraceae family spreading over the first main cluster. Together, this study showed that the combination of these three molecular marker systems rather than independently could be useful tool for comprehensive evaluation of genetic diversity among and within Asteraceae species in Egypt.