The Phylogeny Of Partial Species In Chinese Iris L.(Iridaceae)

By the method of molecular systematics,more than 70% Iris species that distribute naturally in China have been analyzed with the chloroplast rbcL and matK gene fragments.Phylogenetic tree based on sequence data showed the relationships among these Iris species.Results in this study basically conform to Zhao's classification system which adopted in The Flora of China(1985).Phylogenetic trees showed that: I.tigridia,I.mandshurica,I.bloudowii and I.flavissima constitute one clade,separated from the species of Sect.Hexapogon(Bunge)Baker,it suggest that I.mandshurica,I.bloudowii and I.flavissima should be placed in a new section,and I.tigridia should be placed in another section based upon the violet purple flower.Belamcanda chinesis and I.dichotoma have very close relationship,and Belamcanda should be classified to genus Iris.In the Phylogenetic tree,I.subdichotoma was in the clade of Subgen.Nepalensis(Dykes)Lawr,it maybe a specie of Subgen.Nepalensis actually.I.confusa and I.japonica have quite close relationship,but they should be treated as distinct species.Subgen.Xyridion Tausch embedded in Sect.Limniris Tausch of Subgen.Limniris(Tausch)Spach,this result still needs a further analysis since it has been rarely studied.In Subgen.Limniris,Our results support the original partition of Sect.Ioniris Spach,but new series should be set up in Sect.Limniris,classifying these species clearly.I.odaesanensis was in Subgen.Crossiris Spach instead of Subgen.Limniris,This specie was a new record in China published in 2004 about which there is less research,it needs more studies on its status.The divergence time of Iris was estimated by the hypothesis of molecular clock.According to the results,Iris originated in the Miocene about 2000 Mya,and Subgen.Nepalensis originated in the late Pliocene,maybe related to the Himalayan orogeny.