| The Brassicaceae has great economic value including many important cropplants that are grown as vegetables (Brassica, Raphanus) and sources of vegetableoils and condiments. The family includes many ornamentals and Chinese traditionalmedicine and so on. Arabidopsis thaliana, which is naturalized in China, has becomethe model organism in many fields of experimental biology.The Brassicaceae has been acknowledged as a natural taxon comprehensively forthe family is well defined by its cross corolla,stamens tetradynamous,silique orsiliqua,and so on.But there are stilI some problems among its tribes,subtribes andgenera. And because of the unclear of the genera delimition,there are many debateson the attaching of some species.So many work should be done to build a naturalsystem.Fruit morphology has great value in classification. This paper intend to providenew proofs by study on Pericarp and seed coat micro-morphology and analyzing ITSgene sequence.Light microscopes are used to examine fruit epidermal features such as the typeof stoma apparatus, the shape of epidermal cells and the anticlinal wall of 83 spiecesof 41 genera in 10 tribe of Brassicaceae from China. It is canculated and analysed thatthe data of the ratio between stoma's length and wide, stoma density and stoma index.The results split the Brassicaceae into 12 types and indicate Trib. Lepidieae,Trib.Arabideae,Trib.Sisymbrieae and Trib.Euclidieae, Trib.Drabeae as polyphylogetictaxon. This paper suggests Trib.Matthioleae be put into Trib. Hesperideae. LepidiumCardaria and Thlaspi are near and Coronopus should be put into the Lepidium insteadof Cardaria. The results also indicate Capsella is near to Trib.Arabideae,and indicatethe relative of Nasturtium,Roroppa and Cardamine and support the relative of Arabisand Arabidopsis, Sisymbrium and Thellungiella. Camelina are near to genera ofTrib.Arabideae.Scaning electron microscopes are used to examine seed coat micro-morphologyof 65 species of 32 genera. The results split the Brassicaceae into 8 types. The resultssupports the idea of grouping Lepidium 3 sections and suggests Lepidium virginicumL. be upgradea as a section-Sect. Accumbentum F. Z. Li, J. Q. Zheng & Z. Y.Sun,sect. nov.. The experiments indicate Isatis is related with Tauscheria and alsoindicate the relative of Nasturtium and Roroppa,.Arabis and Arabidopsis are bothpolyphyletic and they should be apart into sections. This experiment supports thatCrucihimalaya and Olimarabidopsis are origined from Arabidopsis. Descurainia andBerteroella are obviously different other species of Trib.Sisymbrieae and C.microcarpa Crantz is near to Arabis and Arabidopsis.The ITS gene sequence of 38 species is distributed into 4 lineages, It alsosupports the idea of grouping Lepidium 3 sections and suggests Lepidium virginicumL. be upgradea as a section-Sect. Accumbentum F. Z. Li, J. Q. Zheng & Z. Y.Sun,sect. nov. The analysis indicates Coronopus Cardaria and Thlaspi are relatedwith Lepidium and supports Isatis and Tauscheria are both put into Trib. Sisymbrieaeby 《The Families And Genera of Angiosperms in China》. The experiment agreesCapsella has more related with Trib. Arabidieae than Trib. Lepidieae,so this papersuggest Capsella should be put into Arabidieae. This sequence also indicates Arabisand Arabidopsis are near and Trib. Sisymbrieae is near to Trib. Brassiceae. Theresults suggest Camelina should be put into Trib. Arabidieae. The sequence indicatesBrassica is related with Sisymbrium and whether Trib.Brassiceae is monophyletic isworth while to further study. Capsella and Camelina are assemble to near Arabis, sothey should be put into Trib. Arabidieae with character of Pericarp. The sequencedoes not support that Rorripa and Nasturtium are united one.The experiment suggests Berteroella should be apart from Trib. Sisymbrieae andbe upgraded from genus to tribe by pericarp and seed coat micro-morphology and ITSgene sequence.
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