Heavy metal toxicity on dehydrogenase activity on rhizospheric soil of ectomycorrhizal pine seedlings in field condition.

The present investigation was carried out to study the toxicity of heavy metals (Zn, Cd, Cu, Ni, Pb and Al) on the dehydrogenase activity of ectomycorrhizal (Suillus leutus, Scleroderma aurantium, Cenococcum graniforme and Boletus spp.) and non-mycorrhizal rhizospheric soil of pine seedlings. The treatment of heavy metals adversely affected the dehydrogenase activity. Inoculation of mixed ectomycorrhizal fungi harbored increased activity of dehydrogenase. It was observed that in absence of ectomycorrhizae, heavy metals drastically reduced the enzyme activity at higher concentration of metals.