毛乌素沙地12种蒿属植物叶的解剖特征

为了进一步研究蒿属植物系统分类及植物适应极旱生环境的机理,运用石蜡切片法,在光学显微镜下观察了毛乌素沙地12种蒿属植物叶的解剖特征。结果表明,12种蒿属植物的叶片分等面叶和异面叶两种类型,叶表皮细胞形状为长条形和不规则型,垂周壁式样为平直、弓形、浅波状和深波状;气孔器以不规则型为主,仅有1种为环列型,保卫细胞椭圆形或圆形,隆起,气孔排列方式为平列型和散乱型,气孔指数差异较大。12种蒿属植物叶片具有明显的强旱生植物结构特征,如叶面积显著缩小,表皮毛发达,角质膜厚,栅栏组织极为发达并具环栅结构,维管束多且具维管束鞘,气孔器密集,均生于表皮细胞水平下面,孔下室较大等。12种蒿属植物的叶解剖特征表现出一定的种间差异,如叶表皮细胞形状、细胞垂周壁式样、气孔指数等,这些特征为蒿属植物种间分类提供了依据。

Leaf anatomic characteristics of 12 species of Artemisia in Mu Us desert

The primary abjictive is to provide experimental evidence for the systematic taxonomy of Artemisia and for plant adaptive abilities to the aridiry.The leaf anatomic characters of 12 species of Artemisia in Mu Us desert were observed with the light microscope under the conditions of paraffin section.The results show that there are two types,the isolateral leaf and the bifacial leaf.The shape of leaf epidermal cells are oblong and irregular.The anticlinal walls can be divided into four types,straight,arched,sinuate and sinuolate.Most of the stomatal apparatuses are irregular,only one specie is cyclocytic.The style of stoma guard cell is oval or circular.Borehole pattern of stomatal has paracytic type and anomocytic type.The results also show the typical structure features of xerophytes:small leaves,thick cuticle vein and hair,developed surrounding paling tissues.Out of their veins there are surrounding bundle sheath.Stomatal is below the epidermal cell and so on.Some characters of the leaf epidermis of 12 species of Artemisia,such as shape of epidermis cell or pattern of anticlinal walls and stomatal index,etc.show more or less difference among the species.Those characters provide experimental evidences for the division of species of Artemisia.