Ultrastructure of the Statocytes and Cells of the Distal Elongation Zone of Arabidopsis Thaliana Under the Conditions of Clinorotation

This paper presents the results of an electron microscope study of the root apices of 3-, 5- and 7- day-old seedlings of Arabidopsis thaliana grown under the conditions of stationary control and clinorotation. We demonstrated both the similarities with the control group and the differences in the ultrastructure of statocytes and cells of the distal zone of elongation under clinorotation. For the first time it was possible to establish the sensitivity of ER bodies, which are granular endoplasmic reticulum derived organelles containing beta-glucosidase, to the influence of simulated microgravity. As a result, an increase in the number and area of ER bodies per section of a cell and in the variability of their forms was detected. The degree of these changes correlated with the duration of clinorotation. The supposition concerning the protective role of ER bodies in plant adaptation to microgravity is based on the data obtained.