Multilocus sequence characterization of the phytoplasma associated with a phyllody disease of gaillardia in India

Phytoplasmas of the group 16SrII are among the most widespread phytoplasmas infecting many vegetables and ornamental crops worldwide. Considering the large molecular diversity and the number of subgroups reported a multilocus gene sequence analysis on 16Sr RNA, s ecY and ribosomal protein genes was applied to characterize a phytoplasma strain detected in gaillardia plant samples showing phyllody and stunted growth and collected during surveys in field-grown plants at Karnataka, India. The sequences of seven phytoplasma strains amplified on the 16S ribosomal gene were identical to each other's, therefore one strain, named GaPP1, was selected for further analysis. The 16S rRNA sequence comparisons showed that the closest phytoplasma sequences on this gene were those of ‘Candidatus Phytoplasma australasia’-related strains (16SrII-D) with a similarity coefficient of 0.83. The additional phylogenies on rp and secY genes, however, further confirmed a close relationships with phytoplasmas enclosed in the ribosomal group 16SrII. This phytoplasma is reported for the first time in gaillardia.