In 1996, a new disease of glaucidium (Glaucidium palmatum Sieb. et Zucc.), causing stunt and witches' broom, occurred in Fukushima Prefecture. Electron microscopy revealed the presence of numerous phytoplasma particles in the sieve tubes of diseased plants. The pathogenic phytoplasma was transmitted by the leafhopper, Scleroracus flavopictus, with 22 species of plants in 10 families being infected after an inoculation test with S. flavopictus. Restriction fragment length polymorphism (RFLP) analysis of PCR-amplified 16S rDNA indicates that the pathogenic phytoplasma is closely related to gentian witches' broom phytoplasma and should be assigned to Western-X disease phytoplasma group. “Glaucidium witches' broom” was proposed for the disease.
