Determining uptake of radio-labile soil cadmium by arbuscular mycorrhizal hyphae using isotopic dilution in a compartmented-pot system

Abstract

asterisk inside a circle sign Here, we examined uptake of radio-labile cadmium (Cd) by arbuscular mycorrhizal (AM) fungi from topsoil historically contaminated by Cd, lead (Pb) and zinc (Zn) from mine-spoil. asterisk inside a circle sign Using compartmented pots, Plantago lanceolata plants were grown with or without AM inoculum, isolated from the same soil as used in the experiment. Uptake of radio-labile Cd was determined from the specific activity in the host plant and measured radio-labile Cd pool in the soil. asterisk inside a circle sign Specific activity of 109Cd in plant shoots showed that 10% of the Cd uptake occurred through AM fungal hyphae. Cd concentrations were greatest in the roots of mycorrhizal plants and the shoots of nonmycorrhizal plants, possibly indicating fungal immobilisation of Cd within the mycorrhiza. asterisk inside a circle sign The method presented here allows discrimination between Cd uptake by roots and hyphae in individual plants. © New Phytologist (2004).