沟稃草属及其近缘属植物颖片微形态特征研究

The Micromorphology of Glumes of Aniselytronand Its Related Genera

通过扫描电镜对沟稃草属及其近缘属共14属20种2变种植物颖片微形态进行观察。结果显示:(1)沟稃草属颖片脉间长细胞长筒形或短筒形,细胞壁波状弯曲,显著增厚;脉间短细胞单生,脉间栓细胞近圆形,脉间硅细胞缺失;脉上硅细胞单生,近圆形,有气孔器,气孔副卫细胞平行形至低圆屋顶形;脉上、脉间刺毛常见,有钩毛,无微毛,有乳突,无大毛。(2)根据颖片微形态特征所构建的系统发育树显示,沟稃草属与早熟禾族植物聚为一支,表明其亲缘关系较近,支持将沟稃草属置于早熟禾族中。(3)沟稃草属与拂子茅属、野青茅属植物相距较远,颖片微形态证据不支持将沟稃草属作为广义拂子茅属的成员,其应该单独成属。

The micromorphology of glumes for 20 species and 2varieties belonging to Aniselytronand its related genera of Poaceae was examined by scanning electron microscope.The results showed that：（1）the glumes of Aniselytronand its related genera were characterized by long tubular or short tubular intercostal long cells with markedly sinuous walls.Intercostal cork cells distributed solitary with the shape of subrotund and intercostal silica bodies were absent.The shapes of silica cells in costal zones were subrotund.Parallel-sides to low dome shaped subsidiary cells were found.Prickles were frequently occurred in both costal zones and intercostal zones.Hook-hairs and papillaes could be seen while no micro-hairs and macrohairs were found.（2）A phylogenetic tree was constructed according to the characters of glumes micromorphology.Aniselytronand Poeae clustered together,which indicated that they have a close relationship and distantly related to Calamagrostis and Deyeuxia.（3）According to the micromorphology of the glumes,we draw the conclusion that Aniselytron should not as a member of Calamagrostis s.l.and should as an independent genus be placed in Poeae.