Skip to main content Accessibility help
  • Get access
    Check if you have access via personal or institutional login
  • Cited by 10
  • Print publication year: 2005
  • Online publication date: August 2009

9 - Tropical plants as chimera: some implications of foliar endophytic fungi for the study of host-plant defence, physiology and genetics



Fungal endophytes are defined as those fungi that live inside plant tissues (e.g. roots, stems, leaves) without causing apparent harm to their host (see Wilson 1995). Although we will also mention stem-associated endophytes (see Evans et al. 2003) and endophytes associated with roots (mycorrhizae; see Herre et al., this volume), throughout this chapter, we will focus primarily on the implications of recent studies of the endophytic fungi that live inside plant leaf tissue. These foliar endophytes are extremely diverse phylogenetically and have been documented in nearly all plants sampled (e.g. mosses, liverworts, ferns, conifers and angiosperms; Carroll 1988; Clay 1988; Petrini 1991; Schultess & Faeth 1998; Frohlich & Hyde 1999; Stone et al. 2000; Arnold et al. 2000; Arnold 2002; Arnold et al. 2003; Davis et al. 2003). Despite the growing recognition of their wide distribution across plant taxa, basic attributes of their biology are still poorly understood. Specifically, endophyte diversity, distributions, life cycles, interactions with hosts and other fungi, and their net chemical, physiological and ecological influences are only beginning to be appreciated and studied. This is particularly true in the extremely diverse tropics.

The best-studied endophytes are ascomycetes belonging to the family Clavicipitaceae. These fungi grow throughout the aboveground tissues of some temperate grass species (e.g. Festuca arundinacea, see Clay & Schardl 2002). Typically, in infected individuals, a single fungal genotype infects a single plant individual.

Arnold, A. E. (2002) Neotropical fungal endophytes: diversity and ecology. Unpublished Ph.D. thesis, University of Arizona
Arnold, A. E. & Herre, E. A. (2003) Canopy cover and leaf age affect colonization by tropical fungal endophytes: ecological pattern and process in Theobroma cacao (Malvaceae). Mycologia 95: 388–398
Arnold, A. E., Maynard, Z., Gilbert, G. S., Coley, P. D. & Kursar, T. A. (2000) Are tropical fungal endophytes hyperdiverse?Ecology Letters 3: 267–274
Arnold, A. E., Mejia, L. C., Kyllo, al. (2003) Fungal endophytes limit pathogen damage in a tropical tree. Proceedings of the National Academy of Science 100: 15649–15654
Bacon, C. W., , Porter J. K., Robbins, J. D. & Luttrell, E. S. (1977) Epichloe typhina from toxic tall fescue grasses. Applied Environmental Microbiology 34: 576–581
Bayman, P., Angulo-Sandoval, P., Baez-Ortiz, Z. & Lodge, D. J. (1998) Distribution and dispersal of Xylaria endophytes in two tree species in Puerto Rico. Mycological Research 102: 944–948
Camacho, F. J., Gernandt, D. S., Liston, A., Stone, J. K. & Klein, A. S. (1997) Endophytic fungal DNA, the source of contamination in spruce needle DNA. Molecular Ecology 6: 983–987
Carroll, G. (1988) Fungal endophytes in stems and leaves: from latent pathogen to mutualistic symbionts. Ecology 69: 2–9
Chiang, Y. C., Chou, C. H., Lee, P. R. & Chiang, T. Y. (2001) Detection of leaf associated fungi based on PCR and nucleotide sequence of the ribosomal internal transcribed spacer (ITS) in Miscanthus. Botanical Bulletin of Academia Sinica 42: 39–44
Chiang, Y. C., Chou, C. H., Huang, S. & Chiang, T. Y. (2003) Possible consequences of fungal contamination on the RAPD fingerprinting in Miscanthus (Poaceae). Australian Journal of Botany 51: 197–201
Clay, K. (1988) Fungal endophytes of grasses: a defensive mutualism between plants and fungi. Ecology 69: 10–16
Clay, K. & Schardl, C. (2002) Evolutionary origins and ecological consequences of endophyte symbiosis with grasses. American Naturalist 160: S99–S127
Clay, K., Cheplick, G. P. & Marks, S. (1989) Impact of the fungus Balansia henningsiana on Panicum agrostoides: frequency of infection, plant growth and reproduction, and resistance to pests. Oecologia 80: 374–380
Davis, E. C., Franklin, J. B., Shaw, A. J. & Vilgalys, R. (2003) Endophytic Xylaria (Xylariaceae) among liverworts and angiosperms: phylogenetics, distribution, and symbiosis. American Journal of Botany 90: 1661–1667
Deckert, R. J., Melville, L. H. & Peterson, R. L. (2001) Structural features of a Lophodermium endophyte during the cryptic life-cycle phase in the foliage of Pinus strobes. Mycological Research 105: 991–997
Evans, H. C., Holmes, K. A. & Thomas, S. E. (2003) Endophytes and mycoparasites associated with an indigenous forest tree, Theobroma gileri, in Ecuador and a preliminary assessment of their potential as biocontrol agents of cacao diseases. Mycological Progress 2: 149–160
Faeth, S. H. (2002) Are endophytic fungi defensive plant mutualists?Oikos 98: 25–36
Faeth, S. H. & Fagan, W. F. (2002) Fungal endophytes: common host plant symbionts but uncommon mutualists. Integrative and Comparative Biology 42: 360–368
Faeth, S. H. & Hammon, K. E. (1997) Fungal endophytes in oak trees: experimental analyses of interactions with leafminers. Ecology 78: 820–827
Ford, V. L. & Kirkpatrick, T. L.. (1989). Effects of Acremonium coenophialum in tall fescue on host disease and insect resistance and allelopathy to Pinus taeda seedlings. Proceedings of the Arkansas Fescue Toxicosis Conference 140: 29–34
Frank, S. A. (1996) Host–symbiont conflict over the mixing of symbiotic lineages. Proceedings of the Royal Society of London B 263: 339–344
Freeman, S. & Rodriguez, R. J. (1993) Genetic conversion of a fungal plant pathogen to a nonpathogenic, endophytic mutualist. Science 260: 75–78
Frohlich, J. & Hyde, K. D. (1999) Biodiversity of palm fungi in the tropics: are global fungal diversity estimates realistic?Biodiversity and Conservation 8: 977–1004
Gilbert, G. S., Mejía-Chang, M. & Rojas, E. (2002) Fungal diversity and plant disease in mangrove forests: salt excretion as a possible defense mechanism. Oecologia 132: 278–285
Gwinn, K. D. & Gavin, A. M.. (1992) Relationship between endophyte infection level of tall fescue seed lots and Rhizoctonia zeae seedling disease. Plant Disease 76: 911–914
Herre, E. A. (1999) Laws governing species interactions? Encouragement and caution from figs and their associates. In Keller, L., ed. Levels of Selection in Evolution. Princeton: Princeton University Press, pp. 209–237
Herre, E. A., Knowlton, N., Mueller, U. G. & Rehner, S. A. (1999) The evolution of mutualisms: exploring the paths between conflict and cooperation. Trends in Ecology & Evolution 14: 49–53
Kiers, E. T., Rousseau, R. A., West, S. A. & Denison, R. F. (2003) Host sanctions and the legume-rhizobium mutualism. Nature 425: 78–81
Lebrón, L., Lodge, D. J., Laureano, S. & Bayman, P. (2001) Where is the gate to the party?Phytopathology 91: 116
Lodge, D. J., Fisher, P. J. & Sutton, B. C. (1996) Endophytic fungi of Manilkara bidentata leaves in Puerto Rico. Mycologia 88: 733–738
Margulis, L. & D. Sagan (2002) Acquiring genomes: a theory of the origins of species. New York: Basic Press
Maynard Smith, J. & , E. Szarthmary (1995) The Major Transitions in Evolution. New York: Freeman
Mejia, L. C., E. Rojas, Z. Maynard et al. (2003) Inoculation of beneficial endophytic fungi into Theobroma cacao tissues. In Proceedings of the 14th International Cocoa Research Conference, Accra-Ghana
Ortiz-Garcia, S., Gernandt, D. S., Stone, J. K. & Johnson, P. R. (2003) Mycologia 95: 846–859
Petrini, O. (1991) Fungal endophytes of tree leaves. In , J. H. Andrews & , S. S. Hirano, eds. Microbial Ecology of Leaves. New York: Springer-Verlag, pp. 179–197
Petrini, O., Sieber, T. N., Toti, L. & Viret, O. (1992) Ecology, metabolite production and substrate utilization in endophytic fungi. Natural Toxins 1: 185–196
Preszler, R. W., Gaylord, E. S. & Boecklen, W. J. (1996) Reduced parasitism of a leaf-mining moth on trees with high infection frequencies of an endophytic fungus. Oecologia 108: 159–166
Rajagopal, K. & Suryanarayanan, T. S. (2000) Isolation of endophytic fungi from leaves of neem (Azadirachta indica A. Juss.). Current Science 78: 1375–1378
Saikkonen, K., Faeth, S. H., Helander, M. & Sullivan, T. J. (1998) Fungal endophytes: a continuum of interactions with host plants. Annual Review of Ecology and Systematics 29: 319–343
Schulthess, F. M. & Faeth, S. H. (1998) Distribution, abundances, and associations of the endophytic fungal community of Arizona fescue (Festuca arizonica). Mycologia 90: 569–578
Stone, J. K., C. W. Bacon & J. R. White (2000) An overview of endophytic microbes: endophytism defined. In , C. W. Bacon & , J. F. White, eds. Microbial Endophytes. New York: Marcel Dekker, pp. 3–29
Suryanarayanan, T. S., Venkatesan, G. & Murali, T. S. (2003) Endophytic fungal communities in leaves of tropical forest trees: diversity and distribution patterns. Current Science 85: 489–493
Webber, J. (1981). A natural biological control of Dutch elm disease. Nature 292: 449–450
Welty, R. E., Barker, R. E. & Azevedo, M. D.. (1993). Response of field-grown tall fescue infected by Acremonium coenophialum to Puccinia graminis ssp. graminicola. Plant Disease 77: 574–575
West, C. P., E. Izekor, R. T. Robbins, R. Gergerich & T. Mahmood (1990). Acremonium coenophialum effects on infestations of barley yellow dwarf virus and soil-borne nematodes and insects in tall fescue. In Quisenberry, S. S. & Joost, R. E., eds. Proceedings of the International Symposium of Acremonium/ Grass Interactions. Baton Rouge: Louisiana Agricultural Experiment Station, pp. 196– 198
Wilson, D. (1995) Endophyte: the evolution of a term, and clarification of its use and definition. Oikos 73: 274–276
Wilson, D. & Carroll, G. C. (1994) Infection studies of Discula quercina, an endophyte of Quercus garryana. Mycologia 86: 635–647
Wilson, D. & Carroll, G. C. (1997) Avoidance of high-endophyte space by gall-forming insects. Ecology 78: 2153–2163
Wilson, D. & Faeth, S. H. (2001) Do fungal endophytes result in selection for leafminer ovipositional preference?Ecology 82: 1097–1111
Wilkinson, D. M. (2001) Horizontally acquired mutualisms, an unsolved problem in ecology?Oikos 92: 377–384
Yue, Q., Wang, C., Gianfagna, T. J. & Meyer, W. A. (2001) Volatile compounds of endophyte-free and infected tall fescue (Festuca araundinacea Schreb.)Phytochemistry 58: 935–941