[Elaboration of the in vitro model system to study the interaction of phytopathogenic mollicutes with plant cells].

The model system based on the sugar beet calluses infected by mycoplasms (mollicutes) was elaborated, and changes in the callus cells morphology under the effect of these microorganisms were also studied. The calluses of sugar beet 3K51 cultivated on the Gamborg medium were infected by phytopathogenic mollicute Acholaplasma laidlawii var. granulum str.118. Under the effect of mollicute infection one could observe changes in the cell morphology of sugar beet calluses: the plant cells were transformed from round to lengthened, the intensity of polyploids forming was increased, their grouping and their total destruction were observed. Data of electron microscopy confirm the presence of the mollicute in the sugar beet calluses: acholeplasma cells were localized between and within undifferentiated plant cells.