Genetic variability and geographic differentiation and endangered medicinal plant Thymus daenensis subsp. daenensis revealed by RAPD Markers

Thymus daenensis is a medicinal, aromatic plantendemic to Iran. Among these species T.daenensis iswidely distributed in western Iran and has extensivepharmaceuticals application. This study was aimed toevaluate genetic diversity and differentiation amongpopulation of T.daenensis from different geographicalregions of Iran using RAPD markers and to determinewhether the genetic distances among the accessions arecorrelated with their geographic distribution patterns.Sixteen primers were used to amplify 145 bands out ofwhich 127(87%) were polymorphic. Cluster and principlecoordinate analysis (PCA) showed that most genotypeswere grouped based on their geographical distribution.PCA was performed to visualize the association amongaccessions in more detail. The results show that the firstthese principal coordinate explain 22.86% of the totalvariation, and they correspond largely to the resultsobtained through cluster analysis. Analysis of molecularvariance (AMOVA) revealed that the differences amongpopulations only accounted for 18.12% of the totalvariation, whereas differences within populations were81.87%. Genetic distances among 4 Iranian populationsshowed that the minimum gene diversity over loci wasobserved in Charmahal population (0.2062), while thehighest gene diversity was found in Isfahan population(0.35).The information obtained here could be valuablefor devising strategies for conservation of this medicinalplant.

کلیدواژه ها:

Thymus daenensis ، Medicinal plant ، RAPD marker ، Genetic diversity