Mycorrhiza: a beneficial Symbiosis
The symbiosis formed between plant roots and certain soil fungi is called mycorrhiza
(= fungus + root).
These fungi provide the plant with an enhanced access to the nutrients and to the water available in the soil, extracting them through their extended mycelium (=fungal growth system).
This enhancement is in part explained by the spatial spread and by the increased interfacial area represented by the mycelium.
In exchange, the plant provides the fungus with energy and all substances derived from the photosynthesis.
As each partner takes profit of the action of the other, the symbiosis is a beneficial one.
Mycorrhizal fungi are pervasive in the environment, in all soil types around the world. With very few exceptions (some tree species, brassicaceae), almost all plant species can form mycorrhizae.
The fungi produced and put to use by MYCOSYM are endomycorrhizal fungi also called Arbuscular Mycorrhizal fungi (AM): they penetrate into the root cells which they need as host to enable their reproduction.
Effects of mycorrhizae on plant development are:
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Increased vigour and biomass due to a better use of nutrients and water;
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Improved resistance to stress conditions (biotic and abiotic)
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Protective effect against contaminants such as heavy metals and other pollutants, by blocking them before they would be absorbed by the plant
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Protective effect against root diseases (soil pathogens) and nematodes
Depending on soil composition, mycorrhizal systems may establish themselves in a natural way. However, when mycorrhizal fungi are absent, or when the soil has become infertile by sterilisation, salinization or by contamination, it is possible to re-create the symbiosis by inoculation.
The mycorrhizal fungus must be provided in the close vicinity of the roots at the time of planting or of transplanting. Also, it is possible to obtain pre-mycorrhized plantlets in the nursery.