{"pk":41360,"title":"‘Candidatus Liberibacter’ in four indigenous Rutaceous species from South Africa","subtitle":null,"abstract":"‘\nCandidatus \nLiberibacter africanus’ (Laf), a phloem restricted, gram negative bacteria of the α-proteobacteria is the agent associated with Citrus greening disease in South Africa. A related bacterium \n‘Candidatus \nLiberibacter africanus spp. capensis’ (LafC) was previously described from an indigenous Rutaceae tree, \nCalodendrum capense. \n This led to the hypothesis that other indigenous Rutaceous trees may also be infected with Liberibacters related to either Laf or LafC. Samples from 289 \nVepris lanceolata, \n231 \nZanthoxylum capense, \nand 234 \nClausena anisata \nwere collected from within the natural distribution of these trees in South Africa. Total DNA was extracted and tested for the presence of a Liberibacter using a generic Liberibacter real-time PCR. ‘\nCandidatus \nLiberibacters’ present in positive samples were characterised by amplifying and sequencing the β-operon, 16S and \nomp \ngene regions. The percentage of Liberibacter positive samples differed per tree species with 6% \nV. lanceolata, \n4% \nZ. capense \nand 11% \nC. anisata \nrespectively, being infected. Phylogenetic analysis of the β-operon and \nomp \ngene regions, revealed unique phylogenetic clusters for Liberibacters associated with each tree species. Phylogenetic analysis from the 16S gene region however indicated that sequences obtained from \nV. lanceolata \nand \nC. anisata \nwere similar to 16S sequences for LafC, whereas that obtained from \nZ. capense \ngrouped on its own. Laf has not been identified from HLB-infected orchards from other Citrus producing countries other than Africa and the Mascarene Islands. The presence of related Liberibacters from indigenous Rutaceae species in South Africa may therefore suggest that Laf originated on the African continent.","language":"en","license":{"name":"Creative Commons Attribution 4.0","short_name":"CC BY 4.0","text":"Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.\n\nNo additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.","url":"https://creativecommons.org/licenses/by/4.0"},"keywords":[],"section":"Abstracts of Presentations at the 3rd International Research Conference on Huanglongbing","is_remote":true,"remote_url":"https://escholarship.org/uc/item/89j7441b","frozenauthors":[{"first_name":"R.","middle_name":"","last_name":"Viljoen","name_suffix":"","institution":"Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria, RSA; \nForest and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, RSA","department":"None"},{"first_name":"E.","middle_name":"T.","last_name":"Steenkamp","name_suffix":"","institution":"Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria, RSA; \nForest and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, RSA","department":"None"},{"first_name":"G.","middle_name":"","last_name":"Pietersen","name_suffix":"","institution":"Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria, RSA;\nForest and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, RSA;\nAgricultural Research Council - Plant Protection Research Institute, Pretoria, RSA","department":"None"}],"date_submitted":"2014-12-20T03:58:49+01:00","date_accepted":"2014-12-20T03:58:49+01:00","date_published":"2014-01-01T01:00:00+01:00","render_galley":null,"galleys":[{"label":"","type":"pdf","path":"https://journalpub.escholarship.org/iocv_journalcitruspathology/article/41360/galley/30959/download/"}]}