First report of group 16SrI, ‘Candidatus Phytoplasma asteris’ associated with Mimosa pudica yellows in Indonesia

Mimosa pudicais a perennial plant, widespread in tropical and sub-tropical regions. Known in English as the “sensitive plant” because of its rapid leaf movements when touched, it is a serious weed in managed grasslands and plantation crops such as coffee, tea and oil palm (Waterhouse, 1993). It is also a popular ornamental plant with medicinal properties.

On SamosirIsland in North Sumatera, M. pudica is a common invasive species of crops and waste areas. In October 2007, leaf yellowing, little leaf and proliferation of axillary shoots (Fig. 1) were observed in plants from roadsides and in crop fields around Pangururan village. Leaf and stem samples were collected from three plants with symptoms and one symptomless plant. Total DNA was extracted and used as a template in a nested PCR assay with phytoplasma universal 16S rRNA gene primers R16F2m/R1 and fU5/rU3. All samples with symptoms yielded PCR products of expected size (~880 bp), and identical HaeIII, RsaI and AluI RFLP profiles. No PCR products were produced with DNA from the symptomless plant. Nested PCR amplicons were purified and directly sequenced (www.dnaseq.co.uk). The 16S rDNA sequences were 100% identical, and deposited in GenBank (Accession No. EU273883). BLAST comparisons of the M. pudica phytoplasma 16S rDNA sequence yielded the highest identity (99%) with those of members of group 16SrI, ‘Candidatus Phytoplasma asteris’.

Phytoplasmas have been found previously in Indonesia associated with diseases such as legume witches’ broom (Roechan et al., 1978), chilli and tamarillo diseases (Harling et al., 2009) and Kalimantan coconut wilt (Warokka et al., 2006). However, none of these have been from ‘Candidatus Phytoplasma asteris’, and to our knowledge, this is the first record of a yellows disease on M. pudica worldwide, its association with a phytoplasma and identification of ‘Ca. Phytoplasma asteris’ in Indonesia.