Initial and residual toxicity of soil-applied thiram on the vesicular-arbuscular mycorrhizal symbiosis

摘要: The effect of the non-systemic fungicide thiram on vesicular-arbuscular mycorrhizal (VAM) symbiosis and Leucaena leucocephala was evaluated in a greenhouse experiment. In uninoculated soil treated with P at level optimal for activity, colonization roots low, did not change as concentration increased from 0 to 1000 mg/kg. When this inoculated VAM fungus Glomus aggregatum, enhanced significantly, but decreased increase until it coincided observed soil. Similarly, symbiotic effectiveness reduced, its expression delayed or completely eliminated thiram. Amending sufficient non-mycorrhizal host growth fully compensated thiram-induced loss activity if levels exceed 125 50 mg thiram/kg, toxicity dissipated within 66 days application. At higher concentrations, chemical appeared be enhanced.