ISSN:
1432-1890
Keywords:
Key words Laccaria bicolor
;
Clone development
;
Population ecology
;
Genetic variability
;
Reproductive strategies
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Mating type allele distribution and phenotypic variability were investigated in field populations of Laccaria bicolor. Sporophores associated with Norway spruce (Picea abies), colonized by natural sources of inoculum and growing in a seed orchard, were sampled to obtain dikaryotic strains and assay their phenotypic variability for traits important to the symbiosis. Basidiospores were also collected for mating type analysis of different mycelia. Four sporophore mating types were identified containing seven A and five B factors. Outbreeding efficiency was estimated at 73.8% and the population was slightly inbred. Crosses with previously characterized L. b icolor strains from two nearby populations identified in total six sporophore mating types and ten A and nine B factors, for an estimated outbreeding efficiency (85.7%) similar to previous studies of more spatially disparate Laccaria spp. populations. Dikaryotic strains were tested for mycelial growth rate, as a measure of their competitive ability, on agar media containing a soluble (NaH2PO4), or an insoluble (CaHPO4) phosphate source. Their ability to solubilize the latter was also tested to assess their relative capacity to access insoluble, inorganic phosphate. In most cases, significant variation was detected among strains from the same site for all variables. On three sites (VC4, VC5 and VC7), each determined previously to possess a uniform mycelial genotype, phenotypic variability was likely due to epigenetic variation among different strains of the same genotype. Possible evidence for dikaryon-monokaryon crosses was observed in vivo on one sample site (VC2) where adjacent mycelia shared two mating factors. The phenotypic variability of different mycelial genotypes reflected their genetic variability observed as mating type allele diversity and underlined the importance of basidiospore dispersal in introducing new genotypes into the population. The reproductive strategies of L. bico lor are discussed and compared to those of other basidiomycete species.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s005720050084
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