Detection and identification of ‘Candidatus Phytoplasma palmae’ strains in Hortensia similis and Pritchardia pacifica in Cuba

Lethal yellowing is the most important disease affecting coconut production worldwide and in America it is associated with the presence of different strains or ribosomal 16S subgroups of the ‘Candidatus Phytoplasma palmae’. A symptomatic ornamental palm plant species (Pritchardia pacifica) and individuals of the insect Hortensia similis were sampled in Cuba from selected areas to verify their possible role in the maintenance and dissemination of this phytoplasma. Both, plant and insect were positive for ‘Ca. P. palmae’ presence as cross verified by RFLP analyses on the 16S rRNA and groEl genes specific amplicons. The cloned sequences of phytoplasmas detected in H. similis are enclosed in the 16SrIV-A subgroup, while those from P. pacifica had different profiles with AluI, HhaI and Sau3A enzymes. Further RFLP analyses on 16S rDNA amplicons confirmed the presence of 16SrIV-A phytoplasmas also in P. pacifica suggesting a possible presence of a mixed infection of diverse phytoplasma strains/lineages. This is the first record of the occurrence of a ‘Ca. P. palmae’ strains in P. pacifica in Cuba and of H. similis as potential insect vector of this phytoplasma.