Endophytes are micro-organisms living within the tissue of a plant as endosymbionts, without causing symptoms of disease.
Some of them are mutualistic symbionts with beneficial effects on their host, such as improved growth or resistance against disease or environmental stress, and are being used as microbial inoculants.
However, pathogens and saprophytes may also be endophytic at some point of their life cycle.
Endophytes are distinct from mycorrhizal fungi or rhizosphere microbes in that they live entirely within the plant.
Where specific variants or cultivars of a species are endophytic, this is detailed on the taxon's page.