不同成熟度烟草叶片细胞超微结构变化规律研究

A Study of Cell Ultrastructure of Tobacco Leaf with Different Maturity Grades

摘要: 对不同生长时期的烟草叶片叶肉细胞超微结构进行了观察研究。结果表明，成熟叶肉细胞细胞器丰富，有8～9个周壁叶绿体，为巨大的长椭圆形，基粒片层清晰，有淀粉粒，少量脂滴。衰老后叶肉细胞叶绿体由长椭圆形趋于圆形，基粒片层逐渐变得杂乱至模糊不清。不同成熟度叶片超微结构变化明显，主要表现在叶绿体片层结构整齐程度、线粒体个数和嵴数以及细胞核核液浓度上。

Abstract: Cell ultra-structure of tobacco leaves was studied. The results show that mature mesophyll cells had 8~9 oval chloroplasts, grana lamellae were distinct, and starch grains and a few lipid droplets could be seen. After the leaf senescence, chloroplasts became round and grana lamellae changed into disarray arrangement and blurring. The uniformity of chloroplast grana lamellae,, the numbers and cristae of mitochondria, and the concentration of nucleus karyolymph were different among different mature grade leaves.