Occurrence of ‘Candidatus Phytoplasma aurantifolia’ (16SrII group) in Bolivia

During a survey for phytoplasma at the PROINPA Foundation, Cochabamba, Bolivia in June 2008, plants of podocarpus (Podocarpus macrophyllus) showed symptoms of shortened internodes, leaf size reduction and proliferation (Fig. 1A) compared to healthy ones (Fig 1B), while those of rose (Rosa sp.) exhibited little leaf and yellowing (Fig. 2). Both podocarpus and rose are widely distributed ornamental plants in the urban area of Cochabamba, and symptoms were observed in at least 20% of plants of each species surveyed at PROINPA. In addition, symptoms of leaf deformation, crinkling, and curling (Fig. 3) were displayed by wild plants of tomatillo (Physalis ixocarpa) growing nearby. Three plants with symptoms and one symptomless plant respectively of each species were collected. A nested PCR with universal 16S rRNA gene primers R16mF2/R1 and fU5/rU3 was carried out from total DNAs extracted from collected plant material. All plants with symptoms yielded PCR amplicons (~880 bp), whilst the symptomless plants did not. PCR products were purified (Wizard, Promega), cloned (pGEM T-Easy Vector, Promega) and sequenced (http: www.dnaseq.co.uk). A representative sequence was deposited in GenBank for podocarpus (FJ207457), rose (FJ207453) and tomatillo (FJ207452). BLAST comparisons indicated that the 16S rDNA sequences of these phytoplasmas showed the highest identity (99%) with those of phytoplasma members of group 16SrII, ‘Candidatus Phytoplasma aurantifolia’. A disease in tomatillo was recently associated with a ‘Ca. Phytoplasma asteris’-related strain in Mexico (Santos-Cervantes et al., 2007). However, no phytoplasmas have been reported associated with diseases in podocarpus or rose in the region. To our knowledge, this is the first report of phytoplasmas of group 16SrII in Bolivia and its association with diseases in podocarpus, tomatillo and rose plants.