铁角蕨属4种植物配子体发育的比较研究

Comparative Research of Gametophyte Development of Four Species in Asplenium

以腐叶土为基质培养铁角蕨(Asplenium trichomanes L.)、阿尔泰铁角蕨[A.altajense(Kom.)Grubov]、假大羽铁角蕨(A.pseudolaserpitii folium Ching)和细裂铁角蕨(A.tenui folium D.Don)的孢子,用光学显微镜观察并比较它们的配子体发育过程,以期为铁角蕨属的系统学研究提供基础资料.结果显示,4种铁角蕨属植物配子体均具有:孢子两面型、单裂缝、周壁具褶皱、书带蕨型萌发,成熟原叶体心形,原叶体具有毛状体等共同特征,表明铁角蕨属的演化处于较进化的系统位置,但它们的毛状体形态和细胞数目明显不同,可为属内分系提供依据.研究发现,4种铁角蕨属植物配子体的边缘细胞形状以及假根的形态和数量均有差异,其叶绿体能象单细胞一样进行无丝分裂,强光照射下叶绿体向相邻细胞的侧壁集中等现象.

The spores of Asplenium trichomanes L. ,A. altajense （Kom.） Grubov,A. pseudolaserpitii folium Ching and A. tenuifolium D. Don are cultivated with leaf mould substrate. Their gametophyte development is observed and compared by light microscope in order to provide basal data for the systematical research of Asplenium. The results indicate the same characteristics of the gametophytes of the four species in Asplenium. Spores are bilateral type, monolete, and with crease perine. Germination is Vittaria-type. Adult gametophytes are cordate,and with trichomes. These features suggest that the systematic position of the evolution of Asplenium is more progressive,but the shape and cell number of their trichomes are different obviously,which can provide gist for the classification of system in genus. There is difference in the shape of prothallial border cells of gametophytes of the four species in Asplenium,as well as the shape and number of rhizoids. We also find the phenomena that the chloroplasts can carry out amitosis like unicell and under high-intensity light the chloroplasts will concentrate to the lateral cell wall of adjacent cells.