Hyperaccumulation of silver by Amanita strobiliformis and related species of the section Lepidella

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 (0.07–1.01 mg kg−1 Ag). The Ag contents of both Amanita species were mostly in the range of 200–700 mg kg−1d.w. with the highest Ag content of 1253 mg kg−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.