Investigating the genetic diversity of three different species of Ziziphora sp. using ISSR markers

In this study, ISSR marker was employed to measure the genetic diversity within and among 29 accessions of Ziziphora specie from different regions of Iran including Z. tenuior, Z. persica and Z. capitata from 19, 5 and 5 geographical region, respectively. A total of 154 bands were amplified, and 86.67%, 81.13% and 84% were polymorphic in Z. tenuior, Z. persica and Z. capitata, correspondingly. Average number of amplified bands for each primer in 29 accessions was 10.26, while average number of amplified bands for each primer in Z. tenuior, Z. persica and Z.capitata was 3.8, 7.6 and 6.8, respectively. The most Polymorphic information content among tenuior, persica and capitata species belonged to UBC-805 (0.46), UBC-811 (0.35) and UBC-824 (0.37) primers respectively. The results of cluster analysis indicated that the ISSR marker could easily separate the tenuior species from the other two species, persica and capitata, although it was unable to separate the latter two species. Analysis of molecular variance (AMOVA) showed that there is a significant differences within the samples. Indeed, 38% of the observed genetic diversity is related to genetic diversity between populations and 62% is related to genetic diversity within populations. The results of principal coordinate analysis (PCoA) demonstrated that the first two vectors explained an 80.3% of the total variance, which shows the high correlation of the selected primers. Therefore, with a smaller number of primers and, as a result, the cost, it is possible to separate the tenuior species from the other two species. Considering that the primers UBC-805, UBC-811 and UBC-812 in the tenuior species contained the most polymorphic information and marker index and also showed 100% polymorphism, they can be used as efficient primers to investigate genetic diversity in this species. Overall, high genetic diversity in the Ziziphora sp. plants were identified in this study, which can be useful in the management and maintenance of the germplasm of this plant.