Molecular phylogeny of Onobrychis persica Širj. & Rech.f. (Fabaceae) based on nrDNA ITS sequences

چکیده مقاله

Iran is one of the main centres of diversity for the genus Onobrychis Miller. Onobrychis persica Širj. & Rech.f. which belongs to Sect. Onobrychis, is a perennial herb with particularly high levels of morphological variation among populations. As the other species of this section, O. persica is an important perennial herb that can be used for high-protein fodder for ruminants and equines, for increasing the nutritive value of drought-resistant pastures due to its nitrogen fixation, and for soil conservation. This study includes 26 specimens from twenty representative wild populations of Onobrychis persica originating from their natural habitats in Iran. The aim of this study is to provide a detailed genetic characterization of O. persica in Iran based on nrDNA ITS sequences. Among the nuclear markers, ITS regions have been especially useful at lower taxonomic levels in many angiosperm groups, including Fabaceae. Total genomic DNA was isolated from dried leaves using the standard CTAB extraction protocol. The ITS region was amplified using the ITS4 and ITS5 primers. For each sample the ITS region was sequenced using the ITS4 primer. ITS sequences of Onobrychis bungei was included in the analyses as outgroup. ITS sequences were aligned with Bioedit Ver. 7.0.5 and adjusted manually. Trees were reconstructed with the Neighbor Joining and maximum likelihood method using MEGA5 software. The aligned ITS data matrix consisted of 482 characters of which 11 characters are variable and parsimony-informative. The trees were reconstructed by NJ and ML analyses of the aligned ITS sequences showed that all populations can be divided in two main groups with high bootstrap values (more than 95%). Thus two apparent ecotypes for this species can be distinguished.