Genetic affinity of Betula pendula from Iran using trnH-psbA chloroplast marker

Birch is one of the oldest remaining tree species in the Hyrcanian forest which categorized in plants with limited distribution, rare and critically endangered. Hybridization and polyploidy are two main reasons for uncertainty in taxonomy of the genus Betula in the world. The taxonomic status and genetic affinity of Iranian population of Betula with other species from this genus were investigated. Leaf samples were collected from four Birch populations form North and North west of Iran and after DNA extraction, trnH-psbA region amplified. Comparative sequence analysis of PCR product from five populations in iran with 17 sequences of other species of the genus Betula recorded in NCBI were done. Phylogenetic analysis indicated that birches were in three clades A, B and C which all Iranian samples located in clade A. Sharestanak population formed the subclade Aa, whereas the Siahmarzkouh, Sangedeh, Nohshar and Marmisho comprised subclade Ab. Based on ABGD method, the birches of Iran comprised three separated groups. Sharestanak sample showed the greatest similarity with Betula pendula based on K2P methods. Finally, this study support the belong of Iranian populations to subgenus Betula.