|Novelli, V. M.|
|Carvalho, S. A.|
|Locali, E. C.|
|Machado, M. A.|
Submitted to: International Organization of Citrus Virologists Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 11/15/2004
Publication Date: 11/30/2004
Citation: Novelli, V., Freitas-Astua, J., Astua-Monge, G., Carvalho, S., Locali, E., Rodrigues, V., Arrivaben, F., Hilf, M.E., Gottwald, T.R., Machado, M. 2004. Widespread occurrence of an endosymbiont bacterium in brevipalpus phoenicis populations in the southeastern region of Brazil. International Organization of Citrus Virologists Proceedings. Interpretive Summary: Mites belonging to the Brevipalpis phoenicis group are vectors for a virus that causes an important disease of citrus called leprosis. Leprosis is common in Brazil, but does not exist in US citrus growing areas. A bacterium found in the mite vectors might influence the ability to transmit the leprosis virus, so knowing how common this bacterium is in mite populations is important to understanding how to control the disease.
Technical Abstract: Brevipalpus phoenicis transmits Citrus leprosis virus (CiLV), the causal agent of citrus leprosis, which is considered the most important viral disease in citrus in Brazil due to the severe symptoms it induces and the high cost involved in controlling the mite vector. The presence of an endosymbiont bacterium belonging to the Cytophaga-Flavobacterium-Bacteroides (CFB) phylum has been recently reported in a B. phoenicis population from coffee trees in Sao Paulo, Brazil. Here, we report the first effort towards determining the prevalence of this endosymbiont in B. phoenicis mite populations from ten different citrus production areas in the southeastern region of Brazil. PCR was performed with primers specific for the amplification of an 832-bp fragment from within the 16S rDNA gene of the endosymbiont. All B. phoenicis populations tested yielded bands of the expected size as assessed in agarose gels, indicating that the bacterium is prevalent in mite populations from cirus orchards. Analysis of the sequence of PCR products from two of the populations confirmed the presence and identity of the endosymbiont in B. phoenicis populations from citrus. Other populations from citrus are being tested for the presence of the bacteria and more sequencing is in progress in order to assess the genetic variability of this organism using both 16S rDNA and the internal transcribed spacer (ITS) region. In addition, studies are being carried out in order to determine if the endosymbiont plays a role in CiLV acquisition and transmission to citrus plants.