采用改良 Knop′s 营养液液体培养基于25℃恒温培养箱中培养龙津蕨(Mesopteris tonkinensis )的孢子,每天光照12 h,黑暗12 h,光照强度为2500 lx.用光学显微镜观察记录其孢子萌发、配子体发育的全过程,为龙津蕨系统学的研究提供配子体发育方面的详实资料.结果表明：成熟孢子深褐色,不透明,两侧对称,极面观椭圆形,赤道面观圆角三角形,具单裂缝,孢子周壁具密集的脊状褶皱.播种后15 d 左右萌发,形成2~5个细胞长的丝状体.孢子萌发类型为书带蕨型(vittaria-type).具单细胞假根,不含叶绿体,基部膨大.20 d 左右发育成片状体,30 d 左右形成幼原叶体,幼原叶体不对称,成熟原叶体心脏形对称,56 d 左右形成成熟原叶体,原叶体发育类型为铁线蕨型(adiantum-type).幼原叶体仅左右两翼顶端细胞产生乳突毛状体,成熟原叶体边缘及背腹面都具少量乳突毛状体,毛状体由单细胞构成.68 d 左右精子器开始出现,精子器近圆球形,由基细胞、环细胞、盖细胞构成.75 d 左右颈卵器出现,成熟颈卵器颈部由3层细胞构成.其侧面观柱状,顶面观为铜面状.颈卵器垂直于原叶体表或向原叶体基部倾斜.另外,根据已知的金星蕨科其他属的配子体发育特征,发现龙津蕨配子体发育的这些特征与他们存在较大的区别,因此龙津蕨系统学位置还有待于进一步研究.%The spores of Mesopteris tonkinensis were artificial cultured in Knop′s liquid culture medium with constant temperature 25 ℃ incubator.Light intensity was 2 500 lx,and light 12 h,dark 12 h every day.And at every stage of the spore germination and gametophyte development had been observed and recorded detalledly under the microscope.We provided a lot of detalled data in the course of gametophytes development of M.tonkineusis ,and evi-dence for phylogenetic studies through these characteristics of spore germination and gametophyte development.The result showed that the mature spores were dark brown,bilateral symmetry and no transparent,elliptical in polar view,rounded triangle in equatorial view,and with a single fracture ,and perisporium with dense ridge folds.The size of these mature spores was 56.1(49.7-61.4)μm×67.2(58.8-69.3)μm.All the data were averages of random measured 10 numerical.The spore germination was Vittaria-type,and the gametophyte development was Adiantum-type.Having rhizoid,they consisted of single cell that had not chloroplasts.And the bottom of rhizoid was enlarge-ment.The spores germinat about 15 d after sowing,forming 2 - 5 cells long of filaments.The prothallial plates formed around 20 d after inoculation.The young prothallium developed about 30 d after sowing,and they were not symmetry.But the mature prothallus was symmetrical cordate type.Mature prothallus were formed about 56 d after sowing.There were some things that papillary trichomes were spreading on upper and lower surfaces and along the margin of prothallium.But the left and right wings apical cells of young prothallium also had papillary trichomes.These papillary trichomes consisted of single cell.Antheridium was appeared on mature prothallus around 68 d after sowing.The antheridium was nearly round ball.It made up of 3 cells.One was a basal cell.The other one was a ring cell.The third was a cover cell.As the antheridium matured,the cap cell dehisced.And the spermatozoids were discharged through the cap cell.Their archegonium had occurrence all most the same time.About 75 days after sowing,archegonium was avallable on the margin and the lower surface of the mature prothallus.The neck of mature archegonium was composed of 3 layers of cells.The archegonium was perpendicular to the surface or inclined to the root-based of prothallus.Their lateral view was column.And the top view was the copper surface shape.The top cells would lost when the archegonium open.The paper preliminary discussed their taxonomic significance.It was discov-ered that these characteristics of M.tonkineusis gametophyte development and other genera of gametophyte develop-ment characteristics in Thelypteridaceae had great difference.Therefore,phylogenetic relationship of M.tonkineusis need to be further investigated.
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