Four Ganoderma species (G . tsugae, G. subamboinense var. laevisporium, A T C C 52419, G. tropicum and G. lucidum) were incubated in liquid medium containing different concentrations o f germanium (Ge) for r up to 20 days at 28° C. Increasing the Ge concentration o f the medium resulted in a gradual decrease in the growth of the fungal mycelium. However, the Ge content in the mycelium increased with increasing Ge concentration. Different species recorded different levels o f tolerance towards the Ge. In each case, the optimum concentration of the incorporated Ge in the medium was established as 100 mg/I fo r both optimal uptake o f Ge by the fungal mycelium and optimal mycelial growth.