减压、低温条件下制样的几种植物液泡图象

样品制作中选用的固定剂不同,在电子显微镜下所得的图象差异甚大。高锰酸钾固定的样品中(Luft 1956,Mollenhauer1959),液泡是一个空泡,核也是一个空泡。用四氧化锇(Palade 1952)和醛类-四氧化锇双固定的样品(Sabatini等1963)核内有物质,但液泡仍是一空泡。所有电子显微技术样品制作都离不开固定、脱水、包埋等过程中化学试剂的反复处理,化学试剂处理细胞会抽去部分细胞内含物;或与细胞某些内含物结合形成络合物。从而

The Image of Vacuole in Some Plant Cells Under Low Temperature and Reduced Pressure

Using Scanning Electron Microscope Cryogenic System CS-1 and improved freeze-etching technique, we observed the specimen of vacuole in the mesophyll cells of Narcissus tazetta and Nicotiana tabacum and in the parenchymatous cell of Eichhornia crassipes, and discovered a loose fibriform network. The networks differ with plants. With SEM it was observed that in the mesophyll cell of N. tazetta, the branches from the thick longitudinal fibriform material formed a central support, and the fine fibriform material from the central support formed a network. In the mesophyll cell of N. tabacum, the network in vacuole was composed of some even fibriform materials, The network in the parenchymatous cell of E. crassipes petiole was like a tree. There were small bubbles strewn between the fibre in the vacuoles of these three kinds of cells.With TEM we also observed a network consisting of some uneven fibriform materials in the vacuole of mesophyll cell of N. tazetta. Since the fibri form materials looked like a ribbon, it was called filmy ribbons. They had the same length, but differed in width, because of the branching of filmy ribbon. Between the ribbons there were many bubbles covered by a layer of thin membrane and linked to the film ribbons by filaments.