Synthesis in Vitro, microanalysis and 31P-NMR study of metachromatic granules in birch mycorrhizas



The synthesis in vitro of metachromatic granules was demonstrated in the mycelia of Paxillus involutus (Batsch) Fr. both in pure culture and associated with birch (Betula pendula Roth) roots. X-ray microanalysis revealed the presence of phosphorus and calcium in the granules of mycorrhizas. Phosphorus-31 NMR spectroscopy was used to identify intracellular orthophosphate and polyphosphates. In the mycelin, orthophosphate represented the major form of phosphorus accumulation, and a small pool of polyphosphate was detected in the oldest phases of culture. On the other hand, an important NMR resonance corresponding to polyphosphates was identified in the spectra of synthetic mycorrhizas. The association between a mycelium and a root seems to modify the metabolism of fungus considerably.