title: Origin and Evolution of the Kiwifruit Canker Pandemic.
abstract: Recurring epidemics of kiwifruit (Actinidia spp.) bleeding canker disease are caused by Pseudomonas syringae pv. actinidiae (Psa). In order to strengthen understanding of population structure, phylogeography, and evolutionary dynamics, we isolated Pseudomonas from cultivated and wild kiwifruit across six provinces in China. Based on the analysis of 80 sequenced Psa genomes, we show that China is the origin of the pandemic lineage but that strain diversity in China is confined to just a single clade. In contrast, Korea and Japan harbor strains from multiple clades. Distinct independent transmission events marked introduction of the pandemic lineage into New Zealand, Chile, Europe, Korea, and Japan. Despite high similarity within the core genome and minimal impact of within-clade recombination, we observed extensive variation even within the single clade from which the global pandemic arose.
authors.affiliation: New Zealand Institute for Advanced Study, Massey University, Auckland, New Zealand.
authors.forename: Honour C
authors.initials: HC
authors.lastname: McCann
authors.affiliation: Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.affiliation: Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.
authors.forename: Yifei
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China.
authors.forename: Dawei
authors.initials: D
authors.lastname: Li
authors.affiliation: Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Pan
authors.affiliation: Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China.
authors.forename: Caihong
authors.initials: C
authors.lastname: Zhong
authors.affiliation: The New Zealand Institute for Plant and Food Research Limited, Auckland, New Zealand.
authors.forename: Erik H A
authors.initials: EHA
authors.lastname: Rikkerink
authors.affiliation: The New Zealand Institute for Plant and Food Research Limited, Auckland, New Zealand.|School of Biological Sciences, University of Auckland, New Zealand.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Templeton
authors.affiliation: New Zealand Institute for Advanced Study, Massey University, Auckland, New Zealand.
authors.forename: Christina
authors.initials: C
authors.lastname: Straub
authors.affiliation: New Zealand Institute for Advanced Study, Massey University, Auckland, New Zealand.
authors.forename: Elena
authors.initials: E
authors.lastname: Colombi
authors.affiliation: New Zealand Institute for Advanced Study, Massey University, Auckland, New Zealand.|Department of Microbial Population Biology, Max Planck Institute for Evolutionary Biology, Plön, Germany.|École Supérieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI ParisTech), CNRS UMR 8231 PSL Research University, Paris, France.
authors.forename: Paul B
authors.initials: PB
authors.lastname: Rainey
authors.affiliation: Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China.|Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China.
authors.forename: Hongwen
authors.initials: H
authors.lastname: Huang
mesh_terms: D029042:Actinidia / Q000235:genetics / Q000382:microbiology*; D002681:China; D005638:Fruit / Q000382:microbiology; D014644:Genetic Variation; D009520:New Zealand; D058873:Pandemics; D058974:Phylogeography; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D044224:Pseudomonas syringae / Q000235:genetics* / Q000472:pathogenicity
keywords: bacterial plant pathogen; disease emergence; genomic epidemiology; pathogen evolution; plant-microbe interactions