Results obtained for S. bovinus suggest a lower Cd translocation to the shoots at 15 mg Cd kg−1 when compared with non inoculated seedlings.
However the increased shoot dry weight of S.bovinusinoculated seedlings at that specific concentration, and in the same proportion as the reduction in Cd concentration, suggests a misleading dilution effect.
At 15 mg Cd kg−1, R. roseolus increased total Cd concentration in the plant (by significantly increasing metal concentration in both parts of the plant) whereas at 30 mg Cd kg−1 this association provided the lowest accumulation.
Contradictory results have been reported on metal uptake by fungi (Jentschke and
Godbold, 2000).
Bücking and Heyser (1994) referred that metal transportation from the ectomycorrhiza to the pine host is partly dependent on the metal concentration of the soil, and Khan et al. (2000) suggested that this effect possibly applies to other heavy metals and it might explain some of the contradictory reports on metal uptake.
In this study, shoot Cd concentrations of R.roseolus-inoculated seedlings indeed remained constant when Cd concentration in the soil increased.
Nevertheless, the different behavior of S.bovinus-inoculated seedlings corroborates that metal uptake capacity is also utterly dependent on fungal species or strains (Jentschke and Godbold, 2000).