Ultrastructural features of the parenchyma of young leaves of Datura stramonium L. systemically infected with potato virus X.
Mosaic symptoms were observed on the tip parts of upper leaves of Datura stramonium L. (2-3 cm in length), systemically infected with potato virus X (PVX); symptoms were absent on basal parts of the same leaves. Virus-like particles were not observed in the parenchyma cells of the basal parts lacking symptoms. Considerable retraction of the plasmalemma from the cell wall and the appearance of vesicles and tubules between them were the most characteristic features of such cells. In the tip parts of the leaves with mosaic symptoms, numerous PVX particles were observed in many parenchyma cells, where they were dispersed in the cytoplasm or grouped in aggregates. As a rule the dispersed PVX virions were associated with specific laminated inclusions. Sometimes virions appeared in areas of the cytoplasm subjected to local autolysis. The tonoplast was often disturbed in infected cells, and virus particles were released into a central vacuole.
Reunov
A V
AV
Institute of Biology and Pedology, Far East Science Centre, USSR Academy of Sciences, Vladivostok 690022, USSR.