The genus Tamarix (Tamaricaceae Link), commonly known as tamarisk, has about 54 to 90 species. This plant is known as a group with high complexity in terms of taxonomy and molecular phylogeny. This genus is one of the complex group of taxa in which multiple evolutionary mechanisms have played role in its evolution. There has been no report on genetic diversity and genetic structure of Tamarix dubia populations. The aim of this study was to illustrate genetic diversity versus genetic differentiation of the species in a geographical context in Iran. In total 112 plants of 23 populations in four geographical regions in Iran were sampled for molecular investigations. We used 100 SRAP loci for genetic analyses of 23 geographical populations. SRAP bands obtained were treated as binary data. Data matrix produced were used for genetic diversity analyses. Polymorphism percentage varied from 16.00% to 30% which indicates a low magnitude of genetic variability. Analysis of molecular variance (AMOVA) test showed significant genetic difference among the populations. Moreover, Fst value was significant for most of the populations indicating that the populations of the species have significant genetic difference. UPGMA dendrogram and MDS plot grouped the samples of each population in a separate cluster representing high intra-population genetic similarity. Heat map constructed based on the SRAP data differentiated the studied trees from each other. In general, the studied populations of T. dubia showed a low magnitude of genetic polymorphism which may be due to low effective population size (Ne), or random genetic drift.

Keywords