Phylogenetic Study Of Hedysarum In China Based On ITS Sequences Of Nuclear Ribosomal And TRNL-F Region Of Cpdna

Sequences of the internal transcribed spacers(ITS) of nuclear ribosomal DNA and trnL-F of cpDNA were analysed to resolve phylogenetic relationships among Hedysarum and its related genera-Stracheya. Onobrychis is the outgroup. 17 speices of 33 individuals were sequenced. Then 2 speices and 1 varietas of ITS sequences from Hedysarum and ITS,ITS2,trnL-F sequences of Onobrychis were downloaded from Genbank. The phylogeny trees were constructed by two methods, maximum parsimony and Neighbor-Joining.ITS sequences in two ways of constructing system has the same topological structure tree,which Support the Sect.Fruticosa is independented from Hedysarum and Stracheya belongs to Hedysarum. Sect. Multicaulia and Sect. Subacaulia have the high similarity.This phenomenon can inferred that in the course of evolution they have very near paternity. It is similar to the phylogeny trees of ITS2.Both trees with MP and NJ method of trnL-F have the same result with the other sequences'tree. But the NJ tree of trnL-F have a little difference with other trees. Stracheya did not cluster with Sect. Obscura.The six trees of ITS,ITS2 and trnL-F Support that Sect.Fruticosa is independented from Hedysarum and Stracheya belongs to Hedysarum. Stracheya can be a section of Hedysarum. In Hedysarum, Sect.Multicaulia and Sect.Subacaulia have the closest relationship. The results also show that the evolution rate of ITS and ITS2 is faster than the trnL - F sequence in Hedysarum. The evolution rate of ITS2 is closed to ITS,about 25%.trnL - F sequence'evolution rate is about 14.1%.From the above, This study supports Choi & Ohashi (2003) point of view. The definition of the Hedysarum have more evidences. They have further exposition about the Systematics relationship under Hedysarum.