梯牧草属(Phleum)叶表皮微形态特征研究

Micromorphology of Leaf Epidermis of Phleum

利用扫描电子显微镜对禾本科梯牧草属及其近缘属共17属35种2变种植物的叶片上下表皮微形态特征进行了研究。结果显示,梯牧草属植物叶片上下表皮脉间长细胞都为长筒形或长菱形,细胞壁平直或弯曲,脉上硅细胞结节形,气孔副卫细胞平行形,脉上刺细胞常见,脉间偶见或缺失,无乳突,无微毛;同时,根据叶表皮微形态性状构建了系统发育树,结果表明梯牧草属与早熟禾族聚为一支,显示其亲缘关系较近,而与燕麦族、剪股颖族和虉草族的亲缘关系则相对较远,因此叶表皮微形态证据支持将梯牧草属置于早熟禾族中。

The micromorphology of the leaf epidermis for 35 species and 2 varieties belonging to Phleum and its related genera of Poaceae were examined by scanning electron microscope. The intercostal long cells on both abaxial and adaxial epidermis of Phleum were long tubular or rhomboid,and the outlines of long cells were straight or curved. The shapes of silica cells in costal zones were nodular. Parallel-sided subsidiary cells were found. Prickles were frequently occurred in costal zones and absent or rarely seen in intercostal zones. No papillaes and micro-hairs were found. Meanwhile, a phylogenetic tree was constructed according to the characters of leaf epidermal micromorphology. Phleum and Poeae clustered together,which indicated that they had the closer relationship and distantly related to Aveneae,Agrostideae and Phalarideae. According to the micromorphology of leaf epidermises. Phleum should place into Poeae.