Abstract: A first insight into the phylogenetic analysis of the Orychophragmus violaceus complex was constructed from complete sequences of nuclear ribosomal DNA internal transcribed spacer regions (ITS􊄯5. 8S) and chloroplast gene matK . The ITS results strongly supported the division of the O. violaceus complex into two major groups : one is composed of O. hupehensis, O. taibaiensis, the other consists of O. violaceus and O. diffusus . The matK phylogenetic trees showed O. diffusus and O. violaceus were the basal members of the complex . From previous karyotype study and the present results , we
considerated that the groups of O. hupehensis and O. taibaiensis should not be allocated in O. violaceus . And two possible ancestral cytotypes were also confirmed by our phylogenetic analysis .Moreover, the biogeographic analysis implied a presumed center of recent differentiation in the region from upper to mid Changkiang River to Qin Mountain .

Key words: Biogeography