The Destructive Tree Pathogen Phytophthora ramorum Originates from the Laurosilva Forests of East Asia

Journal of Fungi

József Bakonyi¹  Ildikó Csorba¹  Bruno Scanu²  Ana Pérez-Sierra³  CliveM. Brasier³  Helen Rees³  AnnaR. Harris³  Jack Forster³  JoanF. Webber³  Hayato Masuya⁴  Seiji Uematsu⁵  MaríliaHorta Jung⁶  Zoltán Nagy⁶  Tomáš Kudláček⁶  Sneha Patra⁶  Thomas Jung⁶  Josef Janoušek⁶  Tamara Corcobado⁶  Ivan Milenković⁶  Koji Kageyama⁷  Ayaka Hieno⁷ 

[1] Centre for Agricultural Research, Plant Protection Institute, ELKH, H-1022 Budapest, Hungary;Department of Agricultural Sciences, University of Sassari, 07100 Sassari, Italy;Forest Research, Alice Holt Lodge, Farnham GU10 4LH, Surrey, UK;Forestry and Forest Products Research Institute (FFPRI), Tsukuba, Ibaraki 305-8687, Japan;Laboratory of Molecular and Cellular Biology, Departament of Bioregulation and Biointeraction, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan;Phytophthora Research Centre, Faculty of Forestry and Wood Technology, Mendel University in Brno, 613 00 Brno, Czech Republic;River Basin Research Center, Gifu University, Gifu 501-1193, Japan;

关键词: epidemic;    lineages;    phylogeny;    evolutionary history;    mating types;    biosecurity;   

DOI  :  10.3390/jof7030226

来源: DOAJ

【 摘 要 】

As global plant trade expands, tree disease epidemics caused by pathogen introductions are increasing. Since ca 2000, the introduced oomycete Phytophthora ramorum has caused devastating epidemics in Europe and North America, spreading as four ancient clonal lineages, each of a single mating type, suggesting different geographical origins. We surveyed laurosilva forests for P. ramorum around Fansipan mountain on the Vietnam-China border and on Shikoku and Kyushu islands, southwest Japan. The surveys yielded 71 P. ramorum isolates which we assigned to eight new lineages, IC1 to IC5 from Vietnam and NP1 to NP3 from Japan, based on differences in colony characteristics, gene x environment responses and multigene phylogeny. Molecular phylogenetic trees and networks revealed the eight Asian lineages were dispersed across the topology of the introduced European and North American lineages. The deepest node within P. ramorum, the divergence of lineages NP1 and NP2, was estimated at 0.5 to 1.6 Myr. The Asian lineages were each of a single mating type, and at some locations, lineages of “opposite” mating type were present, suggesting opportunities for inter-lineage recombination. Based on the high level of phenotypic and phylogenetic diversity in the sample populations, the coalescence results and the absence of overt host symptoms, we conclude that P. ramorum comprises many anciently divergent lineages native to the laurosilva forests between eastern Indochina and Japan.

【 授权许可】

Unknown