张氏红山茶叶片适应于环境的解剖特征

Anatomical Characteristics of Blade Adapted Itself to Environment in Camellia changii

张氏红山茶Camellia changiiYe是一年多次开花的植物,它具有全缘、倒卵形的叶,其异面叶具有异型结构的特点:叶的上表皮由1层偶见2层、下表皮由2层细胞组成复表皮,角质膜上覆盖着颇厚、透明的蜡被层;气孔器主要分布在下表皮,气孔口略凹陷,保卫细胞外面常由3个不等大的副卫细胞包围;栅栏组织由1层、偶见2层圆柱状的细胞组成;海绵组织多数,常见首尾相接连成网状;叶脉维管束由纤维细胞组成的扁圆形的维管束鞘包围,维管束鞘两端开放,小脉维管束鞘则由薄壁细胞组成;中脉的维管束鞘外具有多层的基本组织细胞,在接近表皮处基本组织中有大型的石细胞,在下表皮紧靠复表皮处分布石细胞带,带宽1～3个细胞,石细胞外形不规则,分枝粗短或不分枝;石细胞带的内侧为海绵组织细胞。张氏红山茶叶片解剖结构特征表明它是旱生性的中生植物,具有适应强阳光生长的生态习性。

Camellia changii Ye is a plant with blooming multi～times throughout the year,its obovate,coriaceous and integer leaves and bifacial blades with heteromorphic structure in anatomy are very different from other species in genus Camellia.Its upper epidermis is consisted of one layer,occasionally two layers of cells,and lower epidermis is consisted of two layers of cells,that i.e.multiple epidermis,outer of cuticle membrane is covered with transparent and compact waxy layer;stomata are mainly distributed on lower epidermis and slightly depressed,guard cells are surrounded by three subsidiary cells of different size;palisade tissue is consisted of one,sometime two layers of cylindrical cells;spongy tissue is consisted of numerous cells of different size and forms,which usually are connected in netted shape;upper side and lower side of the veins are coverer by flat circle vascular bundle sheath of fiber cells,the two ends of vascular bundle sheath are open.There are multiple layers of ground tissue,and some big stone cells and crystal cells in them,a team of stone cells is formed in parenchyma cells along main vein near epidermis especially besides its lower side,and the stone cell team is 3～4 stone cells in breadth.The stone cell is unequal in size and radially ramose.Its special structure showed that it is a xeromorphic mesophyte and possess some possibility to resistant strong sunlight.