不同盐度下互花米草根结构的比较研究

以不同盐度下生长的互花米草(Spartina alterniflora)为材料,采用常规石蜡切片法对其根的横切结构进行显微观察,比较不同盐度下互花米草根结构的特点及变化规律,研究互花米草根对盐浸环境的适应性。观察结果显示:(1)互花米草根只有初生结构;(2)成熟根的表皮细胞基本毁坏、脱落;(3)互花米草根具有发达的外皮层和皮层通气组织,内皮层细胞壁五面加厚明显,且随盐度的升高呈先增大后减小的趋势;(4)维管柱中央被机械组织所填充,中柱鞘细胞壁也出现加厚现象。互花米草根的结构体现了其对盐浸环境的适应性特征。

Comparative Study of Spartina alterniflora Root Structure under Different Salinity

Conventional paraffin sectioning was used to observe the crosscutting structure of Spartina alterniflora roots grown under different salinities. To examine the plant's adaptability to salty environments, the characteristics and changes in root structure were compared along with changes in salinity. Results showed the following: (1) The roots of S. alterniflora were of primary structure; (2) The epidermal cells of the mature roots were destroyed and mostly fell off, while the exodermis and cortex aerenchyma were well-developed; (3) The endodermis cell walls thickened obviously in five surfaces, increasing at first and then decreasing; (4) The central vascular cylinder was filled with mechanical tissues, and the pericycle cell walls were also thickened. The structural characteristics of these roots showed the adaptation of S. alterniflora to salty environments.