ectomycorrhizal fungi (left) and the proportion of lead translocated to agar, distant from the site of lead addition, through the fungal mycelium. Source: Data from Vodnik et al. (1998).

In an experimental system, Vodnik et al. (1998) investigated the movement of lead through the mycelia of four ectomycorrhizal fungi, each having a different tolerance to lead as a pollutant. They showed that lead uptake by Pisolithus tinctorius (1.1% of the total lead added to the experimental system) was much less than uptake by Laccaria laccata and Suillus bovinus (6.2% and 5.4%, respectively). Internal translocation of lead and its release into the environment at a distance from the site of uptake was also different between species. Some 45% of the lead taken up by Laccaria laccata was released in a different part of the mycelium, whereas only 10% was released by Suillius bovines, showing a greater

EC50 (mmol m−3)

Cd Pb Zn Sb Lactarius deliciosus 0.79 45 100 0.66

Paxillus involutus 2.3 25 188 50

Suillus variegatus 0.008 25 343 50

Suillus granulatus 12.6 2.5 336 5.0

Suillus luteus 0.42 25 284 50

Source: Data from Hartley et al. (1997a).