Abstract
• Recent studies suggest that some plants may circumvent N mineralization carried out by saprotrophs because their ectomycorrhizal fungi have the capacity to hydrolyse protein. When complexed by tannins, however, proteins may be unavailable to some ectomycorrhizal fungi. • Here we tested the hypothesis that when protein-tannin complex is the N source, Pisolithus tinctorius will promote N uptake into red pine (Pinus resinosa) only in the presence of saprotrophs. • The model protein-tannin complex was stable at field pH. P. tinctorius could not obtain N from it, but saprotrophs could. Pre-treatment of the complex by saprotrophs did make its N available to ectomycorrhizal fungi. However, when the protein-tannin complex was the major N source, P. tinctorius increased shoot P but not N content, even in the presence of saprotrophs. • Interactions between saprotrophs and ectomycorrhizal fungi may be different for N and P because of immobilization of N by ectomycorrhizal fungi, or by the more rapid diffusion of ammonium than phosphate, rendering the absorptive surface area of ectomycorrhizal fungi superfluous for uptake of N but not for P.
Original language | English |
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Pages (from-to) | 131-139 |
Number of pages | 9 |
Journal | New Phytologist |
Volume | 159 |
Issue number | 1 |
DOIs | |
State | Published - Jul 1 2003 |
Keywords
- Ectomycorrhizal fungi
- Interaction
- Nitrogen cycling
- Pinus resinosa (red pine)
- Protein-tannin complex
- Saprotrophic microorganisms