Abstract
The influence of different N sources on medium pH variation and the effect of the external mycelium of arbuscular mycorrhizal fungi on nutrient dynamics were studied using a two-compartment, aseptic Petri plate system. VA mycorrhizal, transformed roots of carrot (Daucus carota L.) were cultured in the proximal compartment and external mycorrhizal mycelium in the distal compartment. The medium in the distal compartament contained N either as NO3 – or as NH4 +. The pH and the anion and cation concentrations were measured every 15 days in filtrates prepared from the distal compartments. Thirteen weeks after colonization, there was a significant basification or a light acidification of the NO3 – and NH4 + medium, respectively. There was no change in NO3 – concentration but a significant decrease in NH4 + concentration. Treatments containing N as NO3 – showed no variation in cations such asCa2+ and Mg2+ or anions such as PO4 2–, and SO4 2– but showed significant increases in the concentration of K+. Treatments containing N as NH4 + showed no variation in cations or anions, except for increases in the concentrations of K+ and Cl–.
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Accepted: 7 March 1996
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Villegas, J., Williams, R., Nantais, L. et al. Effects of N source on pH and nutrient exchange of extramatrical mycelium in a mycorrhizal Ri T-DNA transformed root system. Mycorrhiza 6, 247–251 (1996). https://doi.org/10.1007/s005720050132
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DOI: https://doi.org/10.1007/s005720050132