Asexual endophytes of grasses: invisible symbionts, visible imprints in the host neigbourhood.

OMACINI, M

Advances in Endophytici research

Springer Verlag

Año: 2014; p. 143 - 157

Asexual fungi from the genus Neotyphodium (Clavicipitaceae) are symbionts of cool-season grasses inhabiting virtually all terrestrial ecosystems. The host plants incur carbon costs to sustain this symbi-osis and, in return, they obtain multiple benefits. These endophytic fungi are often considered to be defensive mutualists because they produce a considerable range of secondary metabolites, which prove to be toxic to livestock or deterrent to insects. Recently, ecologists have begun to recognize the critical role played by this grass-endophyte symbiosis in the structure and functioning of natural and human-made communities. In this chapter, I identify different path-ways through which the presence of endophytic plants or their dead tissues (litter) can alter the fitness of non-symbiotic plants. Those pathways lead to show how these symbionts impact on the perfor-mance of non-symbiotic neighbours and their interaction with multi-ple above- and belowground ecosystem components. Finally, I dis-cuss the relevance of placing these pathways under the spotlight in order to understand the processes that determine the frequency of symbiotic plants within a population and ecosystem functioning. Es-timating endophyte impacts on host fitness must consider ad-vantages or disadvantages transferred to conspecific plants in the neighbourhood, co-existing as a consequence of inefficiencies during the transmission from plants to seeds.