title: Population dynamics of the ectomycorrhizal fungal species Tricholoma populinum and Tricholoma scalpturatum associated with black poplar under differing environmental conditions.
abstract: Fungi combine sexual reproduction and clonal propagation. The balance between these two reproductive modes affects establishment dynamics, and ultimately the evolutionary potential of populations. The pattern of colonization was studied in two species of ectomycorrhizal fungi: Tricholoma populinum and Tricholoma scalpturatum. The former is considered to be a host specialist whereas T. scalpturatum is a generalist taxon. Fruit bodies of both basidiomycete species were mapped and collected over several years from a black poplar (Populus nigra) stand, at two different sites. Multilocus genotypes (= genets) were identified based on the analysis of random amplified polymorphic DNA (RAPD) patterns, inter-simple sequence repeat (ISSR) patterns and restriction fragment length polymorphisms (RFLPs) in the ribosomal DNA intergenic spacer (rDNA IGS). The genetic analyses revealed differences in local population dynamics between the two species. Tricholoma scalpturatum tended to capture new space through sexual spores whereas T. populinum did this by clonal growth, suggesting trade-offs in allocation of resources at the genet level. Genet numbers and sizes strongly differ between the two study sites, perhaps as a result of abiotic disturbance on mycelial establishment and genet behaviour.
authors.affiliation: Laboratoire Evolution et Diversité Biologique, UMR 5174 CNRS-UPS-ENFA, Bât. 4R3, Université Paul Sabatier-Toulouse III, 118 route de Narbonne, 31062 Toulouse Cedex 9, France. gryta@cict.fr
authors.forename: Hervé
authors.initials: H
authors.lastname: Gryta
authors.forename: Fabian
authors.initials: F
authors.lastname: Carriconde
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Charcosset
authors.forename: Patricia
authors.initials: P
authors.lastname: Jargeat
authors.forename: Monique
authors.initials: M
authors.lastname: Gardes
mesh_terms: D000363:Agaricales / Q000235:genetics / Q000254:growth & development*; D004271:DNA, Fungal / Q000235:genetics*; D021903:DNA, Ribosomal Spacer / Q000235:genetics*; D017753:Ecosystem; D005800:Genes, Fungal; D018895:Microsatellite Repeats / Q000235:genetics; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D032107:Populus / Q000382:microbiology*
chemical_list: D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer