Endophytic Fungi

Abstract

Endophytic fungi are those that colonise the tissues of virtually all terrestrial plants species. Endophytism has evolved multiple times among disparate lineages of fungi. Thus, there are currently no natural systems for classifying endophytic fungi. Not surprisingly, their impacts on host plants may be negative, neutral or positive depending on both fungus–host combination and environmental conditions. From an ecological point of view, endophytic fungi may function nonexclusively as weak pathogens, saprotrophs or mutualists, depending on circumstances. Because some interactions between endophytic fungi and plants are highly beneficial to plants, particularly under stressful conditions, there is an interest in inoculating agricultural crops with particular fungal strains to improve yield. However, care must be exercised because a fungus that is beneficial to one plant species under particular circumstances may be less so under other circumstances or to other plant species.

Key Concepts

  • Endophytic fungi colonise living tissues of virtually all terrestrial plants.
  • Multiple lineages of fungi have evolved to engage in this symbiosis.
  • Transmission of fungal propagules may be either vertical or horizontal.
  • When the transmission is horizontal, colonisation may be limited by distance to inoculum source.
  • Endophytic fungi benefit from the symbiosis, but the net effect on the plant may be positive, neutral or negative.
  • Some endophytic fungi may function as plant pathogens under certain circumstances.
  • Some endophytic fungi may function as decomposers of plant litter.
  • Some endophytic fungi may confer a substantial benefit to their host plants.
  • Because endophytic fungi influence traits that determine plant fitness, it is useful to consider the symbiosis a holobiont.
  • Endophytic fungal inoculants are being considered in agricultural systems, but their impacts on nontarget plant species need to be carefully considered.

Keywords: biotrophic; decomposer; endophytic; holobiont; mutualistic; pathogenic; saprotrophic fungi

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Further Reading

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Rho H, Hsieh M, Kandel SL, et al. (2018) Do endophytes promote growth of host plants under stress? A meta‐analysis on plant stress mitigation by endophytes. Microbial Ecology 75: 407–418.

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Koide, Roger T(Nov 2019) Endophytic Fungi. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0027206]