title: High gene flow and outcrossing within populations of two cryptic fungal pathogens on a native and non-native host in Cameroon.
abstract: In this study, we determined the genetic diversity of 126 isolates representing both Lasiodiplodia theobromae and Lasiodiplodia pseudotheobromae, collected from Theobroma cacao and Terminalia spp. in Cameroon, using simple sequence repeat (SSR) markers. SSR alleles showed clear genetic distinction between L. theobromae and L. pseudotheobromae, supporting their earlier separation as sister species. Both L. theobromae and L. pseudotheobromae populations from Cameroon had high levels of gene diversity, moderate degrees of genotypic diversity, and high levels of gene flow between isolates from T. cacao and Terminalia spp. There was no evidence for geographic substructure in these populations across the region studied, and the SSR alleles were randomly associated in both species, suggesting outcrossing. The significant levels of aggressiveness, evolutionary potential represented by high levels of diversity, outcrossing and gene flow between geographically and host defined populations, identify these fungi as high-risk pathogens for their native and non-native hosts in Cameroon.
authors.affiliation: Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Private Bag X20, Hatfield, Pretoria 0028, South Africa.
authors.forename: Aime Didier
authors.initials: AD
authors.lastname: Begoude Boyogueno
authors.forename: Bernard
authors.initials: B
authors.lastname: Slippers
authors.forename: Guillermo
authors.initials: G
authors.lastname: Perez
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Wingfield
authors.forename: Jolanda
authors.initials: J
authors.lastname: Roux
mesh_terms: D001203:Ascomycota / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification* / Q000472:pathogenicity; D002099:Cacao / Q000382:microbiology*; D002163:Cameroon; D003433:Crosses, Genetic; D051456:Gene Flow; D005800:Genes, Fungal; D014644:Genetic Variation; D005838:Genotype; D058889:Molecular Typing; D016533:Mycological Typing Techniques; D058974:Phylogeography; D010935:Plant Diseases / Q000382:microbiology*; D029766:Terminalia / Q000382:microbiology*