Respiratory activity of intact and excised ectomycorrhizal mycelial systems growing in unsterilized soil
Ectomycorrhizal mycelial systems were grown in unsterile soil using specially designed growth chambers, and the respiratory activity of the mycelium was measured before and after its excision from the host roots. Approximately 30% of the total respiration in the intact system was attributable to the mycorrhizal mycelium in the soil. Severance of mycelial connections at the roots lead to a greater