Orchid mycorrhizae are endomycorrhizal fungi which develop symbiotic relationships with the roots and seeds of plants of the family Orchidaceae. Nearly all orchids are myco-heterotrophic at some point in their life cycle. Orchid mycorrhizae are critically important during orchid germination, as an orchid seed has virtually no energy reserve and obtains its carbon from the fungal symbiont.[1][2]
The symbiosis starts with a structure called a protocorm.[3] During the symbiosis, the fungus develops structures called pelotons within the root cortex of the orchid.[4]
Many adult orchids retain their fungal symbionts throughout their life, although the benefits to the adult photosynthetic orchid and the fungus remain largely unexplained.
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