This study is performed in order to determine the boundary among different species of genus Tilia in Hyrcanian forests by using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). All samples belong to six species of Tilia begonifolia, Tilia rubra, Tilia dasystyla, Tilia xeuchlora, Tilia sabetti and Tilia cordata. In addition to these species, Identification of some other collected samples was not possible just with morphological studies and we introduced them as the No. 8 tree and No. 11 tree. Thus for appellation of these species complementary studies are required. Based on the revealing results, 11 bands in poly acrylamide gel were observed. Dendrogram of cluster analysis showed that separation of populations and species occurred relatively. The complete separation has occurred for two species T. cordata and T. xeuchlora and has been effective in separation of two species T. rubra and T. begonifolia. The protein markers in genetic diversity studies could be valuable as a recognition character.
