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Abstract: Two ectomycorrhizal macrofungal Amanita species of the section Lepidella, A. strobiliformis and A. solitaria, were found to hyperaccumulate silver (Ag). All samples were collected from non-argentiferous areas with background Ag content in soils (0.07–1.01mgkg−1 Ag). The Ag contents of both Amanita species were mostly in the range of 200–700mgkg−1 d.w. with the highest Ag content of 1253mgkg−1 in one sample of A. strobiliformis. Silver concentrations in macrofungal fruit bodies were commonly 800–2500 times higher than in underlying soils. A. strobiliformis and A. solitaria are the first eukaryotic organisms known to hyperaccumulate Ag. [Copyright &y& Elsevier]

Basidiomes of 43 samples of eight Amanita species were gathered from different habitats of Hungary. The mineral composition (22 elements) was analysed by the ICP method in three independent replications, and mineral compositions found as discussed and compared. The Amanita species analysed were very different in As-, Cd-, Cr-, Mo-, Mn-, Se- and mainly in V-content. Other elements (Al, B, Ba, Ca, Co, Cu, Fe, Mg, Na, Ni, Sr, Ti, Zn) occur in the basidiomes in balanced concentrations. The K and P contents have the lowest differences. Summarizing all the data (n=43), the average mineral status of species of Amanita can be deduced. The lowest variability measured was for K and P, and the highest for chromium, nickel and vanadium.Specific, significant accumulation was found only for vanadium, due to the previously demonstrated occurrence of a binding molecule amavadine in the basidiomes of A. muscaria. Remarkable Cd-levels were estimated in A. pantherina and A. muscaria (11.4 and 12.3 mg kg-1D.M., respectively). The higher contents of other elements (e.g. K, practically in all species; Se in A. strobiliformis) are analytical facts but, not accumulations.The mineral compositions of the ectomycorrhizal genus Amanita, of litter decomposing Agaricus and of wood decaying Trametes were compared. Some significant differences were found (AsAmanitaKTrametes; PAmanita>PTrametes) but it seems that the mineral composition of the basidiomes is practically independent of the ectomycorrhizal habit. The specificities of the fungi-tree symbiotic interactions are known, and well documented (higher uptake and transport of certain elements first of all of P), however, the differences found in the mineral components are due to other factors (e.g. substrates, accumulating ability) and not to the mycorrhizal status. [ABSTRACT FROM AUTHOR]

Basidiomes of Amanita alboverrucosa, A. ochrophylla, and A. pyramidifera were collected from native mixed sclerophyll forest sites and of A. conicoverrucosa and A. punctata from planted stands of Eucalyptus maculata in New South Wales, Australia. DNA was extracted from stipe tissue and subjected to inter-simple sequence repeat (ISSR) PCR analysis conducted using the primers (GTG)5 and (GACA)4 in order to determine genotype distribution at each site. Two to nine genotypes of one of the species were identified at each field site. Genotypes of A. ochrophylla, A. conicoverrucosa and A. punctata were spread over areas of ca 10–60 m diam, suggesting vegetative spread via large below-ground mycelial genets. In contrast, genotypes of A. alboverrucosa were more spatially restricted, suggesting recent establishment via basidiospores and more limited below-ground vegetative spread. Two groups of A. pyramidifera basidiomes that were separated by ca 600 m were found to be of the same genotype. While this might reflect long distance spread of below-ground mycelium in this taxon, the proximity of the basidiomes to a roadway makes movement of vegetative basidiome tissue via vehicular activity and subsequent establishment equally plausible. [ABSTRACT FROM AUTHOR]

This issue of Mycological Research News features: Vagaries in interest in natural products by drug discovery companies. The first paper in this issue describes the application of topological analysis to hyphal branching patterns in fungal colonies for the first time. Molecular phylogenetic papers concern the relationships of genera and species of Peronosporaceae, South American Cortinarius species, Amanita spp. genotypes in Australian sclerophyll vegetation, new cryptic species of Albatrellus, Cantharellus and Ophiostoma, and the occurrence of group I introns in Beauveria bassiana. The sterols of field and fungicide resistant Cercospora beticola have been studied, and three novel illudins are described from Coprinopsis episcopalis. An innovative seed-baiting technique to detect different orchid mycorrhizas at the same time has also been devised, and local site variations in fungi on pine needles is documented. The following new scientific names are introduced in this part: Albatrellus citrinus, Cantharellus cascadensis, and Ophiostoma kryptum spp. nov.; and O. crenulatum (syn. Ceratocystiopsis crenulata) comb. nov. [ABSTRACT FROM AUTHOR]