Zinc uptake by mycorrhizal and uninfected roots of Pinus radiata and Araucaria cunninghamii

Uptake of zinc from solution by uninfected roots, ectomycorrhizas of Pinus radiata, and endomycorrhizas of Araucaria cunninyhamii occurred by a non-metabolic phase and by metabolically mediated absorption. The metabolically mediated absorption of Zn was 1.4–4.5 times greater for ectomycorrhizas than for uninfected roots and 2.6 times greater for endomycorrhizas than for uninfected roots. Part of the increase with ectomycorrhizas was due to their larger size than uninfected roots and when corrected for this, the uptake/cm² was 1.4–3.0 times greater. The roles of mycorrhizas in uptake of Zn and other trace elements from soil are discussed.