中文摘要：

采用扫描电镜和焦锑酸钙沉淀的电镜细胞化学法，研究了番茄花柄脱落过程中离区细胞以及钙分布的变化。结果表明：离区的分离开始于皮层与维管束周围小细胞，先在这两个区域出现少量不连续的胞间空隙，并逐渐在维管组织区形成连续的断裂面，此后断裂面向中央的髓部组织延伸，先是维管组织的分离，然后是最中间的髓部以及最外侧表皮组织。钙分布研究发现脱落发生之前钙主要分布在细胞壁、质膜及液泡中。脱落发生后，钙颗粒主要分布在退化细胞壁和细胞间隙中，少量分布在细胞质中。皮层、维管束以及髓部细胞在整个脱落过程中钙分布以及钙形态明显不同，这可能是造成离区各组织在脱落中有不同分离程度的主要原因。

英文摘要：

Cell ultrastructure and calcium distribution during tomato pedicel abscission were studied by using scanning electron microscopy and antimoniate precipitate calcium electromicroscopic cytochemical methods. Results showed that the abscission was initialed in cortex and cellule around vascular bundle on which two inconsecutive cell interspaCeSr appeared firstly, and later the cell interspaces of vascular bundle formed consecutive separation parts gradually. As the abscission procession happened, separation parts were extended to middle of abscission plate, then vascular bundle ruptured, and the marrow tissue and outer epidermis separated at latest. Ca^2＋ location analysis showed that before abscission calcium iron mainly concentrated within vascular and vacuole, cell wall and cell membrane of cortex and marrow. After abscission there was a mass calcium deposition in vascular bundle, when marrow separated, calcium grain mainly in degraded cell wall and intercellular space, little detected in cytoplasm. In abscission there was a great difference in calcium location and contents between cortex, vascular and marrow which would be mainly caused by different separation procession of the abscission zone tissue.