Abstract: The anatomical structure of leaves in four species of ornamental grasses,Iris lactea.var.chinensis,Carex lanceolata,Pennisetum alopecuroides,Phalaris arundinacea var.picta,were studied by using paraffin sections and microscope technology,in order to provide anatomical foundation for their wide application in future. We observed the size and arrangement style of epidermis cells,veins and mesophyll cells in the leaves of these ornamental grasses. For I. Iris lactea. var.chinensis,the cuticle on the epidermal cells and the whole leaf were thicker,mesophyll cells were multilayered in neat arrangement,and the huge air cavity was intersected in the middle mesophyll. Sclerenchyma cells were attached to upper and lower epidermis,above or below parallel veins. And there was abundant tannin in the mesophyll cells. As for Carex lanceolata,the upper epidermal cells were 4~5 folds larger than the lower ones,and the layer number of mesophyll cells in the adaxial plane were bigger than that in the abaxial plane. The gas cavity between the mesophyll was developed,which was separated by leaf vein so as to form a huge gas chamber;Furthermore,the bulliform cells in the middle vein were large and numerous,so the leaf can fold and close into half when lacking water. The leaf structure of Pennisetum alopecuroides was similar to that of Miscanthus. It is a C₄ plant,with large,medium and small veins arranged alternately,and pith cells were in the mid-vein. In Phalaris arundinacea var.picta there were large bulliform cells above the mid-vein,and small gas cavity among the mesophyll cells. Some mesophyll cells contained chloroplasts,and some having leucoplast,respectively,corresponding to the yellow-green or white-green stripes on the leaf surface. The leaf anatomical structures of the four ornamental grasses showed that Iris lactea.var.chinensis,Carex lanceolatax and Phalaris arundinacea var.picta could not only adapt to arid lands because of their structure traits,but also to wet lands with developed gas cavity;Iris lactea.var.chinensis are also resistance to cold;Pennisetum alopecuroides has strong adaptability to drought and tropical high temperature habitat.

Key words: Iris lactea Pall. ‘chinensis’ (Fisch.) Koidz., Carex lanceolata Boott, Pennisetum alopecuroides L. Spreng, Phalaris arundinacea L.‘picta’., Anatomical structure

摘要： 本研究对马蔺（Iris lactea Pall. ‘chinensis’.）、披针叶苔草（Carex lanceolata Boott）、紫穗狼尾草（Pennisetum alopecuroides （L.） ‘Spreng’）和花叶虉草（Phalaris arundinacea L. ‘picta’）叶片解剖结构进行了观察，为其广泛应用提供解剖学理论基础。观察表明：马蔺叶片较厚，角质层也厚，叶肉细胞多层，排列整齐，叶片富含单宁，有巨大的气腔横亘在中部叶肉层间，平行叶脉上下有厚壁细胞；披针叶苔草上表皮是下表皮的4~5倍大，近轴面叶肉细胞层数多于远轴面，叶肉层间气腔发达，中脉处泡状细胞大而多；紫穗狼尾草是典型的C₄植物，大、中、小叶脉相间排列，中脉有髓细胞；花叶虉草叶肉细胞间有小气腔，叶肉含叶绿体或白色体，与叶面黄绿色或白绿色条纹相对应。4种观赏草叶片结构显示，马蔺、披针叶苔草和花叶虉草可适应干旱环境和湿生环境；马蔺具有一定的耐寒性；紫穗狼尾草对干旱和热带高温生境均有较强的适应性。

关键词: 马蔺, 披针叶苔草, 紫穗狼尾草, 花叶虉草, 解剖结构