光轴肿足蕨配子体发育及其系统学意义

Gametophyte Development in Hypodematium hirsutum and Its Systematic Significance

采用改良Knop′s液体培养基对光轴肿足蕨(Hypodematium hirsutum(D.Don)Ching)的孢子进行培养,观察其孢子萌发和配子体发育过程。结果表明,成熟的孢子深褐色,不透明,两面体型,单裂缝,极面观椭圆形,赤道面观为豆形,周壁褶皱。接种18天后孢子开始萌发,孢子萌发为书带蕨型,播种25天左右发育为3～5个细胞的丝状体,35天左右发育为片状体,50天左右形成幼原叶体,原叶体发育为三叉蕨型。幼原叶体不对称,成熟的原叶体呈对称心形。原叶体边缘及背腹面都具单细胞乳头状的毛状体。播种65天左右开始出现性器官,精子器近圆球形,由3层细胞构成,成熟颈卵器颈部由4～5层细胞构成。光轴肿足蕨的配子体发育特征表现出较为进化的特点。

The spores of Hypodernatiurn hirsuturn （D. Don） Ching were artificial cultured, and the spore germination and gametophyte development were observed under the microscope. The mature spores were dark-brown, bilateral type, monolete, bean-shaped in equatorial view and elliptical in polar view with a wrinkled perines. The spore germianation pattern occured about 18 days after inoculation and was of the Vittaria-type. The gametophyte development was of the Aspidium-type. Filamentous growth appeared within 25 days after inoculation and formed a fil- ament of 3 ~ 5 cells. Prothallial plates growth appeared within 35 days after inoculation. The young prothallium developed about 50 days after sowing. They were not symmetry,but the ma- ture prothallium was symmetrical cordate type with one type hair. Antheridia were appeared on prothallus 65 days after inoculation. The pelletlike was consisted of three cells while the neck of mature archegonium was composed of 4-5 layers of cells. The characteristics of spore germination and gametophyte development were relatively advanced, and its taxonomic significance was discussed preliminarily.