七叶一枝花根的显微结构及其内生真菌分布研究

Microstructure and endophytic fungus distribution of the root of Paris polyphylla

本文采用石蜡永久制片和光学显微摄像的方法对七叶一枝花Parispolyphylla根的显微结构及其内生真菌的分布进行了研究。结果表明,七叶一枝花的根茎由栓皮层、薄壁组织及维管组织组成,其中栓皮层由4层细胞组成;薄壁组织的细胞含有丰富的营养物质,其内有时分布有针状结晶束。不定根由表皮层、皮层、内皮层及维管束构成,表皮上有根毛,皮层所占根径的比例达80%以上;木质部为三原型。在七叶一枝花的根茎和不定根的皮层细胞中均有内生真菌的分布。真菌由表皮、外皮层侵入到皮层薄壁组织,在皮层薄壁细胞中形成菌丝结,并扩展成一定的侵染区域,部分皮层细胞中菌丝结已被消化吸收。内生真菌只侵染皮层薄壁细胞,不侵染维管柱。七叶一枝花可以通过消化细胞内的菌丝作为营养的来源之一。

Microstructure and distribution of endophytic fungi of the root of Paris polyphylla were studied through permanent paraffin-cut section and optical microscope photography. The results indicated that the rhizome of P polyphylla consisted of cortex, parenchyma and vascular cylinder. The cortex was composed of four layer cells, and the parenchyma cells were abundant in inclusions, in which the cylinder were sometimes observed. The adventitious roots of P. polyphylla consisted of epidermis, cortex and endoderm. The epidermis had many root hairs, the cortex occupied more than 80% of the diameter of root, and the xylem had three ridges of protoxylem. The hyphae of endophytic fungi were colonized only in cortex of rhizome and adventitious root. They infected the cortex parenchyma through epidermis and exodermis, and then, formed pelotons, and expanded their occupying area of cortex. The pelotons were digested and absorded in some cells.