title: A possible centre of diversity in South East Asia for the tree pathogen, Ceratocystis manginecans.
abstract: The fungal pathogen, Ceratocystis manginecans, has caused serious canker and wilt disease on Mangifera indica (mango), on legume tree species in Oman and Pakistan and on Acacia spp. in Indonesia. A Ceratocystis species, with similar morphology to C. manginecans, has recently been reported in Vietnam, causing severe disease of Acacia trees. Previous population genetic studies on isolates from M. indica in Oman and Pakistan have shown that the pathogen represents a single clonal haplotype, indicative of an introduced pathogen. The aim of this study was to investigate the genetic diversity and population structure of 160 C. manginecans isolates, from four host-associated populations from Oman, Pakistan, Indonesia and Vietnam. This was done by applying a combination of 14 previously developed microsatellite markers and a new set, designed in this study from two different C. manginecans genomes. Sequence data confirmed that the isolates in Vietnam are the same species as those in Indonesia and were thus identified as C. manginecans. Unlike the populations in Oman and Pakistan, relatively high levels of genetic variation were found for the isolates from Indonesia and Vietnam. The Vietnam population was significantly differentiated from the other populations and isolates from this area had the highest level of genetic diversity thus far encountered for the pathogen.
authors.affiliation: Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, 0002, South Africa.
authors.forename: Arista
authors.initials: A
authors.lastname: Fourie
authors.affiliation: Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, 0002, South Africa.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Wingfield
authors.affiliation: Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, 0002, South Africa.
authors.forename: Brenda D
authors.initials: BD
authors.lastname: Wingfield
authors.affiliation: Forest Protection Research Centre, Vietnamese Academy of Forest Sciences, Dong Ngac, Tu Liem, Hanoi, Vietnam.
authors.forename: Pham Q
authors.initials: PQ
authors.lastname: Thu
authors.affiliation: Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, 0002, South Africa. Electronic address: irene.barnes@fabi.up.ac.za.
authors.forename: Irene
authors.initials: I
authors.lastname: Barnes
mesh_terms: D000045:Acacia / Q000382:microbiology; D001203:Ascomycota / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D001210:Asia, Southeastern; D004271:DNA, Fungal / Q000235:genetics*; D021903:DNA, Ribosomal Spacer / Q000235:genetics*; D014644:Genetic Variation; D016681:Genome, Fungal; D006239:Haplotypes; D031022:Mangifera / Q000382:microbiology; D018895:Microsatellite Repeats; D010802:Phylogeny; D058974:Phylogeography; D010935:Plant Diseases / Q000382:microbiology; D014197:Trees / Q000382:microbiology*
chemical_list: D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer
keywords: Acacia spp.; Ceratocystis manginecans; Mango trees; Population genetic diversity; Vietnam