Quote:
Flowda said: WOw I have found morels in the wild, and I enjoyed this thread, because previously I didn't think they could be cultivated except by soaking picked wilds ones in water for a bit, then dumping the spores into prime areas and hope they latch onto some good root systems so they can mycorrhizally take over the entire area. Morels are great.
Morels are not usually mycorrhizal, but they are opportunistic. Actually they will send hyphae out to areas where there is already damage to a root system in order to aquire nitrogen/nutrients that have built up around the damage location.
Mycorrhiza
There has been an allusion to Morchella being mycorrhizal. The question is its relationship to plant roots.
The term mycorrhizal is becoming almost meaningless in the broadness of its use. All soil microbes more or less have a relationship to plant roots. The rhizosphere is where everything happens in the soil. Soil bacteria, including Pseudomonas fluorescens, cluster around plant roots, because nutrients accumulate over time in that area. Roots promote that result, since they benefit from the accumulation of nitrogen.
It has been found that Morchella Mycelium aggregates around plant roots and breaks down the outer layers of tissue (Buscot). This result is not the same as that of true mycorrhizal fungi. The observed result with Morchella was clumping around large roots rather than an association with fine roots.
If one therefore chooses to refer to Morchella as mycorrhizal, which is arbitrary, doing so tells nothing about the biology involved. It certainly does not lead to additional conclusions in regard to nutrition or plant specificity. Certainly plant roots are not required for the growth or nutrition of Morchella, since it grows readily in various composts. The study showing Morchella Mycelium aggregating around roots also indicated that the Mycelium initially grows in the soil without such aggregations.
It is possible that Morchella derives some nutrients directly from plant roots. But if it does, some form of root damage would apparently have to occur before root nutrients would be significantly available to the Mycelium. Evidence for the role of root damage is in the tendency for morels to be found in large numbers where there have been forest fires or trees dying from such factors as dutch elm disease. However, these nutrients are probably indirect, as bacteria probably precede Morchella in utilizing them.
Buscot, F. 1989. Can. J. Bot. 67:589-593./ 1992. J. Plant Physiol. 141:12-17.
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