mycorrhiza

Product of close association between the branched, tubular filaments (hyphae) of a fungus and the roots of higher plants. The association usually enhances the nutrition of both the host plant and the fungal symbiont. The establishment and growth of certain plants (e.g., citrus plants, orchids, pines) depends on mycorrhizae; other plants survive but do not flourish without their fungal symbionts.

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