The investigation of chloroplast marker trnL-F in determination of different between two species of Populus: Populus caspica and Populus alba

The purpose of this study is to evaluate of the choloroplast trnL-F marker’s power in genetic differentiation and phylogenetic relationships between Populus caspica and Populus alba. The 15 leaf samples collected from seven different growthing areas of hyrcanian forests, Iran; Guilan and Mazandaran provinces. Genomic DNA extracted from leaves using the CTAB and SDS-potassium acetatate combined method. PCR performed by universal primers and amplified trnL-F fragments sequenced. Results showed that, the entire length of the trnL-F region was 392-394 nucleotides in both species. In compaire to available sequences of the GenBank, Adenin and Thimine nucleotides in P. caspica and P. alba are more than other nucleotides. These two species have shown high similarity in nucleotide composition of trnL-F spacer region with minimum gegetic distance (=0.005). Parsimony analysis of 582 characters revealed 178 constant, 56 variable, 151 parsimony informative and 46 characters are unique positon. Too, bootstrap consensus trees showed that the trnL-F sequence data cannot distinguish P. caspica from P. alba because, investigated samples have located in common group. Therefore, for accurate recognition of this species, phylogenetic reconstruction using other choloroplastic and nuclear markers suggested.