Fine-scale genetic analyses reveal unexpected spatial-temporal heterogeneity in two natural populations of the commercial mushroom Agaricus bisporus.
This study examined the fine-scale genetic variation of the commercial mushroom, Agaricus bisporus, over 2 years at two sites in France. One site was a meadow fertilized with horse manure and disturbed regularly by humans; the other was a Monterey cypress forest free of human disturbance. Altogether, 50 mushrooms were collected and analysed for mitochondrial and nuclear genetic variation marked by RFLPs and multilocus enzyme electrophoretic polymorphisms. Population samples from these two sites were genetically different and both sites contained high levels of genetic diversity. No identical genotypes were found at either site between the 2 years and there was little evidence for extensive vegetative clonality for this species. Contrary to expectations, very limited evidence of pseudohomothallic reproduction was found. Results from tests of Hardy-Weinberg equilibrium and genotypic equilibrium showed that outcrossing and recombination have played significant roles in both populations. The results demonstrated spatial-temporal genetic heterogeneity of A. bisporus in natural populations.
Xu
Jianping
J
Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, CanadaL8S 4K11.
Desmerger
Christophe
C
Centre Technique du Champignon, Munet, 49400 Distré, France2.
Callac
Philippe
P
Institute National de la Recherche Agronomique, Unité de Recherche sur les Champignons, B.P. 81, 33883 Villenave d'Ornon, France3.
D000364:Agaricus / Q000166:cytology / Q000235:genetics*; D005075:Biological Evolution; D003433:Crosses, Genetic; D005787:Gene Frequency; D005819:Genetic Markers; D014644:Genetic Variation / Q000235:genetics*; D005838:Genotype; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D011995:Recombination, Genetic; D012098:Reproduction; D013997:Time Factors
D005819:Genetic Markers