Phytoplasma diseases: a review of 50 year history and current advances

Phytoplasma diseases were known long before the discovery of their agent. Since the early 1930s in the former Soviet Union the infectious nature of the disease known under the name of “stolbur of tomato” has been recognized. Attempts were made to find vectors of the disease (I.K. Korachewski, 1934; V.L. Ryzhkov et al., 1934). In 1945 it was found that planthopper Hyalesthes obsoletus can be the disease vector (K. Sukhov et al., 1946). Searching for an infectious agent of plant diseases with symptoms of dwarfism, yellowing, damaged leaves and generative organs, which was unable to grow on artificial nutrient media was unsuccessfully conducted for several decades in our country and abroad. The discovery was made only in 1967 by Japanese researchers (Y. Doi et al., 1967). The causative agent of the disease, the unknown earlier phytopathogen from Mollicutes class, was similar to mycoplasma pathogens of animals. Later it was found that the life cycle of phytoplasmas is associated with the phloem cells of the plants, in which they multiply, and with vector insects of Hemiptera order which are feeding plant juice and able not only to support the phytoplasma reproduction in their body, but even transmit phytoplasma to the offspring...