The vacuole system in stomatal cells ofAllium. vacuole movements and changes in morphology in differentiating cells as revealed by epifluorescence,video and electron microscopy

Summary The development of autofluorescent vacuoles in the stomatal cells ofAllium cepa andA. vineale was investigated using fluorescence microscopy of live cells, low light level television, cytochemistry and electron microscopy. During cell differentiation, the vacuole undergoes two major changes in morphology. In an intermediate form, it consists of a reticulum or network of interlinked tubules and small chambers. The network is formed from globular cisternae in very young GMCs and is maintained as a reticulum until it is transformed back into a globular form later in the differentiation of guard cells. The network thus remains intact through the course of one cell division. During its existence, the reticulum undergoes complex movements and rearrangements. The significance of these changes in the vacuole is discussed in terms of vacuole ontogeny and function and the mechanisms that control motility in plant cells.Abbreviations used DIC differential interference contrast - TV television - L³TV low light level television - GMC guard mother cell - I²V double image intensifier vidicon - I³V triple image intensifier vidicon - CCU camera control unit - SEG special effects generator - VTR video tape recorder - VCR video cassette recorder - TDG time-date generator - TBC time base corrector - SYNC synchronization - BL blanking - VD vertical drive - HD horizontal drive - PMT photomultiplier tube - ALC automatic light compensation - LED light emitting diode.