【摘要】 DAPI是一种方便而又可靠的,专一性强的DNA染料,紫外光下DAPI-DNA复合物显示浅蓝色荧光,在高度稀释的DAPI溶液中(0.5ppm)浸泡植物材料2—24小时,细胞核即可染色。经浸染的材料仍有胞质环流现象,幼苗在同样的溶液中可正常的生长。所用方法对于植物材料中核穿壁现象的初步检查是适用的。以往对于核穿壁的研究结果主要来自单子叶植物,本研究更多地采用了双子叶植物。有些材料直接取自植物的某些器宫,有的采用徒手切片。切片包含几层细胞,以避免损伤和挤压可能引起的人工膺象。初步检查表明,所用植物材料具核穿壁现象的所占比例是相当大的,尽管每种材料所见的核穿壁细胞数目并不相同。一般地说,核穿壁见于胚性组织,急剧生长的组织,衰老组织以及短命组织,而在成熟的,具正常功能的器官中是没有的。更多还原

【Abstract】 DAPI (4,6-Diamidino-2-phenylindole) has been shown in this investiga- tion to be a convenient and reliable DNA-specific nuclear stain which will exhibit pale blue fluorescence under ultraviolet irradiation. It could be employed to stain the nu- cleus in living plant specimens by simply immersing them in highly diluted DAPI solu- tion (ca. 0.5 ppm) for 2-24 hours. The specimen with stained nucleus is still capable of exhibiting cyclosis. The seedling may grow steadily in such solution. Hence, the whole procedure is well suited for the preliminary survey of occurrence of nuclear ex- trusion in various higher plants chosen at random. As most investigations on nuclear extrusion have been intensively conducted on two monocots (wheat and Allium), special attention is paid to dicots. Free hand sections consisting of several layers of cells in thickness are taken from the various parts of a plant (flower bracts, petals and stipule) to avoid artificial indlced by injury and stripping. The main findings are summarized in Table, and the microscopic record illustrated in figures. The preliminary survey has adequately demonstrated that the frequency of successful detection of nuclear extrusion in plant samples taken at random is rather high although its occurrence is rare. Pa- tient search under microscope is usually required. In general it is present in embryo- nic as well as in senescent tissues and in tissues of transitory existence such as the leaf hairs, but it is absent in mature normal function-organs. The results are in conformity with those of prefious observations.更多还原