The Study Of Didvmocarpus S.Str Systematics

Didymocarpus Wall. S. Str belongs to Gesneriaceae.The wholle world has180species.Chiana has31species,3varieties.The phylogenetic relationshipsofSmilacaceaewere comprehensively investigated by means of comparative seed coat,palynology,morphologicalcladistic and molecular systematics which was based on three DNA regions.Theresults were summarized as follows：Pollen morphyology of scannong electron microscope on Didymocarpus and relatedplants use to study.three distinct pollen types grouped were distinguished：D.mollifoliusW.T.Wang D.sinoprimulinusW.T.Wang.one:Finelyreticulate:D.salviiflorusChunD.cortusifolius(Hance)H.LévD.heucherifoliusHand.-MaTwo;CoarselyreticulateD.praeteritusB.L.Burtt&R.Davidson.D.purpureobracteatus W.W. Sm.There tuberculate Gyrocheilos chorisepalumW.T.WangThe pollen of Didymocarpus Wall. S. Str and Gyrocheilos chorisepalumW.T.Wang have3colporate.Amb is3-lobed circular.P/E of The pollen of Didymocarpus Wall. S.StrP/E betwen1.09and1.28.Then pollen study suppored Weber and Burtt’vie.Seed macromorphology and seed—coat micromorphology ofDidymocarpusWall. S. Str、Gyrocheilos and Chirita of16species were observed under lightmicroscope and scanning electron microscope.The seeds are Long cylindricalcones.Conico acuminate.Oval and so on.The seed coat of Didymocarpus Wall. S.Str is smooth,but Gyrocheilos’s are slightly rough.Chirita’s has high.Inferred from the separate and combined analyses based on two DNA regions (ITSand trnL-F) of Didymocarpus Wall. S. Str and its allies, the systematic position ofGyrocheilos and phylogenetic relationships within subgenera of Didymocarpus Wall.S. Str were discussed：The taxa of DidymocarpusS.Str. included in this study formed astrongly supported multivariata clade.the most plants of Didymocarpus S.Str.arecomparison of proximal relationship with Chirita.