Cytokinesis in Impatiens balsamina and the effect of caffeine.

A description of cytokinesis in cells of roots of Impatiens balsamina is given, and the effect of caffeine on this process. The disposition of organelles, microtubules and vesicles which form the new cell plate is similar in normal and caffeine treated roots. In sections cut in the plane of the developing cell plate, membranous arms radiating from common centres appear to play an important role in promoting efficient fusion of the vesicles, and caffeine reduces their occurrence. The possible presence of callose in the newly formed cell plate, and the formation of plasmodesmata, are discussed. Mechanisms of membrane fusion and effects of caffeine on this event are also considered.