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aGlobal Plant Clinic, CABI, Bakeham Lane, Egham, Surrey, TW20 9TY, UK; b Agricultural Advisory Society, House # 8/7 (Ground Floor), Block-B, Lalmatia, Dhaka-1207, Bangladesh; and c PROINPA, Av. Meneces s/n Km.4 (zona EI Paso), Cochabamba, Bolivia All peoples have names for and knowledge of plants, animals and other things in the real world. An ethnopathology (or, more strictly, ‘ethnophytopathology’) ‐ study in Bangladesh, Uganda and Bolivia revealed that smallholder farmers label plant health problems with meaningful names. A local name for a plant health problem typically has two kinds of meaning. The first is a literal translation of the name, often a kind of shorthand description of the symptom. The second and most important kind of meaning is the denotative meaning (the thing in the real world which the name actually refers to). Local words for plant health problems often label the symptom rather than the actual disease. This is logical, since smallholders cannot observe microscopic causal organisms. Local concepts for plant health problems do not necessarily classify the natural world in exactly the same way that scientists do, yet local terms for plant health problems are still meaningful. It is not clear if folk classifications of plant health problems are phylogenetic classifications (e.g. ‘mammals’ vs. ‘fish’) or ecological (e.g. ‘seafood’ vs. ‘meat and poultry’). Cross-culturally, local knowledge recognizes that plants are alive, and that they may be ill or healthy, perhaps in analogy with human health.

Mimosa pudica is 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 Samosir Island in North Sumatera, M. pudica is a common invasive speciesof crops and waste areas. In October 2007, leaf yellowing, little leaf and proliferation ofaxillary shootswereobserved 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. TotalDNAwasextractedandusedasatemplate inanestedPCRassaywith 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 PCRampliconswerepurifiedanddirectlysequenced(http://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%) withthoseofmembersofgroup16SrI, ‘CandidatusPhytoplasmaasteris’. 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’. 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.

In November 2006, researchers at the Ministry of Agriculture, Forestry and Fisheries, first observed symptoms of witches’ broom on cacao trees in the Union Vale, La Dauphine, and Robot estates in Saint Lucia. The disease has since been found in other smallholder plots throughout the island. Estate managers report up to 50% of the cacao trees are infected. Diseased trees have dense, slightly curved proliferations of shoots with shortened internodes (witches’ brooms), arising from the lateral buds. Other symptoms include leaf necrosis, distortion and enlargement of the leaf lamina and veins, and stem swellings. Brooms in cacao are characteristic of infection by the fungus Moniliophthora perniciosa (formerly Crinipellis perniciosa ). In May 2007, samples of older, well-dried brooms were sent to the Global Plant Clinic, UK for confirmation of the pathogen. Aggregations of white saprotrophic hyphae were seen under the bark, which under microscopic examination revealed clamp connections that are characteristic of M. perniciosa . A more definitive morphological identification was obtained by inducing the fungus to produce basidiocarps. Brooms were suspended in a cabinet and subjected to a daily cycle of wetting and drying. The subsequent basdiocarps were pink, tinged with crimson and had a delicate pileus that was radially grooved with fluted edges. Fungal mycelia isolated directly from the brooms were also tested using molecular characterisation. The ITS regions of the rDNA was amplified and sequenced with fungal specific primers ITS6 (Cooke & Duncan, 1997) and ITS4 (White et al ., 1990). The sequence obtained (GenBank Accession No. EU861393) showed greater than 99% homology to 16 strains of this species held in the GenBank database. Witches’ broom of cacao is endemic to the Amazon basin region of South America, but has spread to plantations in the Americas and several Caribbean islands. This fungus can cause up to 90% pod losses and is considered to be one of the main limiting factors for cacao production in South America and the Caribbean islands (Griffith et al ., 1994). The disease has previously been recorded from the Caribbean islands of the Dominican Republic, Grenada, St Vincent and Grenadines and Trinidad and Tobago, but this is the first confirmed report of witches’ broom in cacao from Saint Lucia.