| The content of this study is about the taxonomic research of Bipolaris Shoemaker in China. More than 300 isolates were received from the 2000 specimens of leafage, deadwood, cortices and seeds, which we collected from Fujian, Jiangxi, Zhejiang, Jiangsu, Anhui, Shaanxi, Gansu, Xinjiang, Sichuan, Henan, Qinghai, Jilin Provinces, Neimengu Autonomous Region, Shanghai, Chongqing and other places.We also observed the HMAS specimens in Academia Sinica.We found and described 29 species. 2 new species are B. alocasiae H. Deng et T.Y. Zhang n. sp and Bipolaris poae-pratensis H. Deng et T.Y. Zhang, n. sp.; 5 new records in China are Bipolaris buchloes (Lefebvre & A.G. Johnson) Shoemaker. B. kusanoi (Nisikado & Miyake) Shoemaker, B. neergaardii (Danquah) Alcorn, B. nicotiae (Mouchacca) Alcorn and B. papendorfii (van der Aa) Alcorn. Other 23 species, which have been reported in China, are Bipolaris austi-aliensis (M.B. Ellis) Tsuda & Ueyama, B.chinensis G.Y. Sun et T.Y. Zhang, B. coicis (Nisikado) Shoemaker, B. Crustacea (Henn) Alcorn, B. cylindrical Alcorn, B. cynodontis (Marignoni) Shoemaer, B. hcnvaiiensis (Ellis) Tsuda & Ueyama, B. heveae (Fetch) J.H. Peng & J.Y. Lu. B. maydis (Nisikado & Miyake) Shoemaker, B. nodulosa (Nerk. & M.A. Curtis) Shoemaker, B. oryzae (Breda de Haan) Shoemaker, B. panici-miliacei (Nisikado) Shoemaker, B. peregianensis Alcorn, B. sacchari (E. Butler) Shoemaker, B. setariae (Saw.) Shoemaker, B. sorghicola (Lefebvre & Sherwin) Alcorn, B. (Sacc.) Shoemaker, B. spicijlrj V3:,ier) Subram., B. stenospila (Drechsler) Shoemaer, B. yamadae (Nisikado) Shoemaker, B. zeicola (Stout) Shoemaker and B. zizaniae (Nisikado) Shoemaker. There were also 3 unknown species, Bipolaris sp Bipolaris sp Bipolaris sp.3, which are possiblly new species.After many research workers studied the genera of Bipolaris, the main results of this research are the revision of the latin and Chinese names of this genus and the species in it. We found more hosts and wider distributions of the fungi in this genus besides finding new species and new records in China, which made us know about them better. What's more, we especially care to study the taxonomic methods and criteria of this genus. Weselected the most adaptive culture medium, temperature and light to produce abundant and natural conidia. We also studied the formation of distosepta. conidia germination, the characters of the formation of conidia on the conidiophores.The results show that most isolates produce enough condia. which are similar to those directly received from the hosts, when they grow on the TWA+W culture media for about 1-2 weeks, under 18-22 and alternative NUV light for 12h and in dark for 12h. But we should try several different kinds of culture media to produce the natural condia for some special species. The first-formed distosptum in conidia of Bipolaris is median to submedian, then the second septum delimits the basal cell of the mature conidium and the third distoseptum is distal. This character can be used to differentiate this genus from other similar genera. The conidia of Bipolaris species germinate principally from one or both polar cells with the basal germ tube originating close to the hilum and growing semiaxially and not germinate from the middle cells. The modes of the growth of the conidia on the conidiophores between species of Bipolaris are similar and the minute differences between them are according to the different shape of the conidia.The taxonomic criteria of Bipolaris species mainly base on the shape of conidia. and the conidiophores between the species are rarely different. The character of the colonies is important for special species. The results show that the characters of conidia shape and color are very important, the steady number of distosepta and the size of conidia are important too. Otherwise, the special hosts corresponding to the species help us identify these species.
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