广西三种主要海草的茎叶解剖结构研究

Stem and leaf anatomical structures of three seagrass species in Guangxi

利用光学显微镜观察了分布于广西北部湾沿岸的三种主要海草(矮大叶藻、二药藻和喜盐草)的茎叶解剖构造。结果表明:(1)三种海草的叶片结构和根状茎均有发达的气腔组织,叶肉及皮层细胞数量较少,且胞间隙明显;(2)叶肉及皮层中夹杂有纤维群,皮层薄壁细胞均有不同程度的木质化现象;(3)维管束结构简化,主要起机械支持作用而非输导功能。这些特征反映出矮大叶藻、二药藻和喜盐草对海洋环境中海浪和潮汐冲击、光等胁迫的高度适应。

Under optical microscope, the anatomical observations were made on the rhizomes and leaves of Zostera ja- ponica, Halodule uninervis and Halophila ovalis. The results were as followed： （1） well-developed aerenchymaes and distinct intercellular space were found both at the rhizomes and leaves structure in all three seagrass species, while mesophylls and cortical cells were less compared to the general terrestrial plants~ （2）fiber clusters were found be- tween mesophylls and cortices, and lignified parenchyma cells were also found inside cortices~ （3）the structures of vascular bundles, playing a role of mechanical support rather than conducting tissue, were simplified. The anatomical structure of leaf and rhizome in these seagrass species reflected their greatly ecological adaptability to the surrounding high-wave and low-light habitat.