地钱生殖托形态结构新观察及其对有性生殖的适应(英文)

New Observations on the Morphology and Structure of Marchantia polymorpha Gametophores in Sexual Reproduction Adaption

用显微观察技术对苔类植物地钱（Marchantia polymorpha）生殖托的形态结构进行了研究，本研究的新观察包括：（1）生殖托具有明显的背腹分化，被认为是叶状体为适应有性生殖而高度特化的直立枝；（2）雌托盘的9～11个指状裂瓣中边缘两个稍不同，除了两个边缘裂瓣外的其他裂瓣间具雌苞。托柄具有背腹之分，雌托柄背面具光合组织，并向两侧扩展形成纵沟，雌托柄的腹面具2条被鳞片重叠覆盖相互平行的纵沟，内具假根；（3）与雌托柄不同，雄托柄外观平滑，背面无光合组织及纵沟。观察发现，伞状的雌托能滞留水分，并沿雌托柄的纵沟缓慢释放连续的水流，游动精子沿着纵沟内的水流到达雌托下面的颈卵器。上述观察表明地钱生殖托的结构是对有性生殖的一种适应，这有助于我们理解地钱受精作用的机理。

The morphology and structure of the gametophores of the liverwort Marchantia polymorpha were studied using light microscopy. New observations included： （1） The gametophores had distinct dorso-ventral differentiation and were highly specialized upright branches of the thallus bearing sex organs. （2） Two marginal ones of 9-11 rays of the female receptacle were distinguished by their slightly different sizes compared with others. There was no involucre between the two marginal ones. The dorsal region of the archegoniophore stalk was comprised of photosynthetic tissue, which extended laterally and formed two narrow grooves under the extended photosynthetic tissue. The ventral region of the stalk consisted of two-parallel rhizoid furrows half-wrapped by overlapping scales. （3） In contrast to the female archegoniophore, the antheridiophore stalk was smooth and no photosynthetic tissue or grooves were formed in the dorsal region. The umbrella-shaped female receptacle retained water, which could be released slowly along the grooves to form a tiny water flow, through which the spermatozoids swam to the archegonia. The morphology and structure of the Marchantia receptacles were adaptations to sexual reproduction, and can help us to understand the mechanism of fertilization in Marchantia.