ARS | Publication request: Localization and relative titer of Candidatus Liberibacter asiaticus in the salivary glands and alimentary canal of Diaphorini citri vector of citrus huanglongbing disease

Submitted to: Florida Entomological Society Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: July 22, 2010
Publication Date: July 23, 2010
Citation: Ammar, E.-D., Shatters, R.G., Hall, D.G. 2010. Localization and relative titer of Candidatus Liberibacter asiaticus in the salivary glands and alimentary canal of Diaphorini citri vector of citrus huanglongbing disease. Annual Meeting of the Florida Entomological Society, July 25-28, 2010, Jupiter, Florida.

Technical Abstract: Candidatus Liberibacter asiaticus (CLas) has been strongly associated with huanglongbing (HLB), or citrus greening, which is the most devastating citrus disease in Florida and other parts of the world. HLB is transmitted in a persistent manner by the psyllid vector Diaphorina citri. We used quantitative polymerase chain reaction to detect and study the relative titer of CLas in dissected organs of individual D. citri adults collected from HLB-infected citrus trees. Percentage of infected salivary glands (43-47 percent) was much lower than that of infected alimentary canals (87-92 percent). However, the relative titer of CLas was significantly higher in both the salivary gland and alimentary canal compared to that in the rest of the body. Only an average of 16% individual HLB-infected adult psyllids transmitted HLB to young potted citrus trees. These results strongly suggest that the salivary gland constitutes a major barrier to CLas infection and/or transmission in D. citri and that CLas may be replicating at least in the salivary glands of its psyllid vector.