title: Ecology and population structure of a tree wound-infecting fungus in a native South African forest environment.
abstract: Ceratocystis tsitsikammensis was first isolated from bark harvesting wounds on two indigenous tree species in the Afromontane forests of the Western Cape Province of South Africa. Inoculation studies indicated that it is a potential pathogen of native Rapanea melanophloeos trees. In this study, we investigated the distribution, ecology and biology of C. tsitsikammensis in the Garden Route National Park of South Africa. Isolates were obtained from wounds on R. melanophloeos, three non-native hosts as well as from nitidulid and staphylinid beetles visiting wounds on these trees. The genetic diversity and population biology of the fungus was examined using microsatellite markers. Its mating strategy was also determined by amplifying its mating type genes and the fungus was shown to be homothallic. Despite the homothallic nature of the fungus, high levels of random mating and absence of genetic structure was found in the investigated population, suggesting a strong effect of gene flow, probably linked to insect dispersal. The gene diversity of C. tsitsikammensis was similar to that of a related fungus, Ceratocystis albifundus, that is known to be native in Africa. This, together with the fact that C. tsitiskamensis is not known elsewhere, within or outside South Africa, suggests that it is native and endemic to the Cape Afromontane region.
authors.affiliation: Department of Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa.
authors.forename: Alain C
authors.initials: AC
authors.lastname: Misse
authors.affiliation: Department of Genetics, FABI, Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa.
authors.forename: Irene
authors.initials: I
authors.lastname: Barnes
authors.affiliation: Department of Conservation Ecology and Entomology, Stellenbosch University, 7600 Stellenbosch, South Africa.
authors.forename: Francois
authors.initials: F
authors.lastname: Roets
authors.affiliation: Department of Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa.
authors.forename: Michael
authors.initials: M
authors.lastname: Mbenoun
authors.affiliation: Department of Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Wingfield
authors.affiliation: Department of Plant and Soil Sciences, FABI, Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Pretoria 0028, South Africa. Electronic address: jolanda.roux@fabi.up.ac.za.
authors.forename: Jolanda
authors.initials: J
authors.lastname: Roux
mesh_terms: D000818:Animals; D001203:Ascomycota / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D001517:Coleoptera / Q000382:microbiology*; D004271:DNA, Fungal / Q000235:genetics; D065928:Forests; D049770:Genes, Mating Type, Fungal; D014644:Genetic Variation; D005838:Genotype; D018895:Microsatellite Repeats; D010935:Plant Diseases / Q000382:microbiology*; D013019:South Africa; D014197:Trees / Q000382:microbiology*
chemical_list: D004271:DNA, Fungal
keywords: Ceratocystidaceae; Ceratocystis; Mating type; Microascales; Nitidulidae; Staphylinidae