title: Latency and Persistence of 'Candidatus Liberibacter asiaticus' in Its Psyllid Vector, Diaphorina citri (Hemiptera: Liviidae).
abstract: Although 'Candidatus Liberibacter asiaticus' (Las) is a major pathogen associated with citrus huanglongbing (HLB), some characteristics of transmission by the psyllid vector Diaphorina citri are not fully understood. We examined the latent period and persistence of transmission of Las by D. citri in a series of experiments at 25°C, in which third-instar psyllid nymphs and 1-week-old adults were confined on infected citrus for an acquisition access period (AAP), and submitted to sequential inoculation access periods (IAPs) on healthy citrus seedlings. The median latent period (LP50, i.e., acquisition time after which 50% of the individuals can inoculate) of 16.8 and 17.8 days for psyllids that acquired Las as nymphs and adults, respectively, was determined by transferring single individuals in 48-h IAPs. Inoculation events were intermittent and randomly distributed over the IAPs, but were more frequent after acquisition by nymphs. A minimum latent period of 7 to 10 days was observed by transferring groups of 10 psyllids in 48-h IAPs, after a 96-h AAP by nymphs. Psyllids transmitted for up to 5 weeks, when submitted to sequential 1-week IAPs after a 14-day AAP as nymphs. The long latent period and persistence of transmission are indirect evidences of circulative propagation of Las in D. citri.
authors.affiliation: First, second, third, and fifth authors: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture, University of São Paulo, C.P. 9, Piracicaba, SP, 13.418-900, Brazil; first author: Agricultural Research Company of Santa Catarina State, Epagri, C.P. 791, Chapecó, SC, 89803-904, Brazil; and fourth author: Centro de Citricultura Sylvio Moreira, IAC, C.P. 4, Cordeirópolis, SP, 13490-970, Brazil.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Canale
authors.affiliation: First, second, third, and fifth authors: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture, University of São Paulo, C.P. 9, Piracicaba, SP, 13.418-900, Brazil; first author: Agricultural Research Company of Santa Catarina State, Epagri, C.P. 791, Chapecó, SC, 89803-904, Brazil; and fourth author: Centro de Citricultura Sylvio Moreira, IAC, C.P. 4, Cordeirópolis, SP, 13490-970, Brazil.
authors.forename: Arthur Fernando
authors.initials: AF
authors.lastname: Tomaseto
authors.affiliation: First, second, third, and fifth authors: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture, University of São Paulo, C.P. 9, Piracicaba, SP, 13.418-900, Brazil; first author: Agricultural Research Company of Santa Catarina State, Epagri, C.P. 791, Chapecó, SC, 89803-904, Brazil; and fourth author: Centro de Citricultura Sylvio Moreira, IAC, C.P. 4, Cordeirópolis, SP, 13490-970, Brazil.
authors.forename: Marineia de Lara
authors.initials: ML
authors.lastname: Haddad
authors.affiliation: First, second, third, and fifth authors: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture, University of São Paulo, C.P. 9, Piracicaba, SP, 13.418-900, Brazil; first author: Agricultural Research Company of Santa Catarina State, Epagri, C.P. 791, Chapecó, SC, 89803-904, Brazil; and fourth author: Centro de Citricultura Sylvio Moreira, IAC, C.P. 4, Cordeirópolis, SP, 13490-970, Brazil.
authors.forename: Helvécio
authors.initials: H
authors.lastname: Della Coletta-Filho
authors.affiliation: First, second, third, and fifth authors: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture, University of São Paulo, C.P. 9, Piracicaba, SP, 13.418-900, Brazil; first author: Agricultural Research Company of Santa Catarina State, Epagri, C.P. 791, Chapecó, SC, 89803-904, Brazil; and fourth author: Centro de Citricultura Sylvio Moreira, IAC, C.P. 4, Cordeirópolis, SP, 13490-970, Brazil.
authors.forename: João Roberto Spotti
authors.initials: JR
authors.lastname: Lopes
mesh_terms: D000818:Animals; D002957:Citrus / Q000382:microbiology*; D006430:Hemiptera / Q000382:microbiology*; D007303:Insect Vectors / Q000382:microbiology*; D009758:Nymph; D010935:Plant Diseases / Q000382:microbiology*; D012230:Rhizobiaceae / Q000502:physiology*
keywords: Asian citrus psyllid; citrus greening; prokaryote−vector relationship; retention time