Identification of 'Candidatus Phytoplasma asteris' (16SrI-B) Causing Witches' Broom Disease of Mallotus japonicus in Korea

Mallotus japonicus with witches' broom disease were observed in Jeollabuk-do, Korea. A phytoplasma from the infected leaves was identified, based on the 16S rDNA, 16S-23S intergenic spacer region, and fragment of rp operon and tuf gene sequences. The 16S rDNA sequences exhibited maximum (99.7%) similarity with Iranian lettuce phytoplasma, the rp operon sequences exhibited 100% similarity with Goldenrain stunt phytoplasma, and the tuf gene sequences exhibited 99.8% similarity with Japanese spurge yellows phytoplasma. Results of the sequence analysis and phylogenetic studies confirmed that the phytoplasma associated with M. japonicus in Korea was an isolate of Aster Yellows group (subgroup16SrI-B).