title: On the evolution and molecular epidemiology of the potyvirus Papaya ringspot virus.
abstract: The potyvirus Papaya ringspot virus (PRSV) is found throughout the tropics and subtropics. Its P biotype is a devastating pathogen of papaya crops and its W biotype of cucurbits. PRSV-P is thought to arise by mutation from PRSV-W. However, the relative impact of mutation and movement on the structure of PRSV populations is not well characterized. To investigate this, we have determined the coat protein sequences of isolates of both biotypes of PRSV from Vietnam (50), Thailand (13), India (1) and the Philippines (1), and analysed them together with 28 PRSV sequences already published, so that we can better understand the molecular epidemiology and evolution of PRSV. In Thailand, variation was greater among PRSV-W isolates (mean nucleotide divergence 7.6%) than PRSV-P isolates (mean 2.6%), but in Vietnamese populations the P and W biotypes were more but similarly diverse. Phylogenetic analyses of PRSV also involving its closest known relative, Moroccan watermelon mosaic virus, indicate that PRSV may have originated in Asia, particularly in the Indian subcontinent, as PRSV populations there are most diverse and hence have probably been present longest. Our analyses show that mutation, together with local and long-distance movement, contributes to population variation, and also confirms an earlier conclusion that populations of the PRSV-P biotype have evolved on several occasions from PRSV-W populations.
authors.affiliation: School of Life Sciences, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4000, Australia1.
authors.forename: Marion F
authors.initials: MF
authors.lastname: Bateson
authors.affiliation: School of Life Sciences, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4000, Australia1.
authors.forename: Rosemarie E
authors.initials: RE
authors.lastname: Lines
authors.affiliation: School of Life Sciences, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4000, Australia1.
authors.forename: Peter
authors.initials: P
authors.lastname: Revill
authors.affiliation: School of Life Sciences, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4000, Australia1.
authors.forename: Worawan
authors.initials: W
authors.lastname: Chaleeprom
authors.affiliation: Hanoi Agricultural University, Gia Lam, Vietnam2.
authors.forename: Cuong V
authors.initials: CV
authors.lastname: Ha
authors.affiliation: School of Botany and Zoology, Australian National University, ACT 2000, Australia3.
authors.forename: Adrian J
authors.initials: AJ
authors.lastname: Gibbs
authors.affiliation: School of Life Sciences, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4000, Australia1.
authors.forename: James L
authors.initials: JL
authors.lastname: Dale
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002213:Capsid / Q000235:genetics*; D036022:Capsid Proteins; D029441:Carica / Q000821:virology*; D004279:DNA, Viral; D019143:Evolution, Molecular; D014644:Genetic Variation; D008969:Molecular Sequence Data; D010802:Phylogeny; D010935:Plant Diseases / Q000821:virology; D019176:Potyviridae / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D013785:Thailand; D014744:Vietnam
chemical_list: D036022:Capsid Proteins; D004279:DNA, Viral; C073700:coat protein, Papaya ringspot virus