Erigeron (Conyza) bonariensis, a host of ‘Candidatus Phytoplasma fraxini’-related strain in Brazil

Erigeron bonariensis, the flax-leaved fleabane is found in several regions of Brazil. In the State of Rio de Janeiro, plants of E. bonariensis exhibiting shortened internodes, reduced leaf size, witches’ broom and yellowing were tested for phytoplasma presence. Amplicons were obtained from nested PCR with primers designed for 16S rRNA and tuf genes. RFLP analyses of the ribosomal DNA revealed similarity to phytoplasmas of the ash yellows group and sequence analyses demonstrated 100% identity with phytoplasma strains belonging to subgroup 16SrVII-B from Argentina and Brazil. The sequence from tuf gene showed a maximum of 94% identity with ‘Candidatus Phytoplasma fraxini’ strain ASY3, and 92% identity with other strains of the ash yellows group. To our knowledge, this is the first report of the species Erigeron bonariensis harboring a ‘Ca. P. fraxini’-related strain in Brazil.