Non-systemic fungal endophytes in Festuca rubra plants infected by Epichloë festucae in subarctic habitats

• Published in: Fungal diversity 2013-05, Vol.60 (1), p.25-32
• Main Authors: Zabalgogeazcoa, Iñigo, Gundel, Pedro E., Helander, Marjo, Saikkonen, Kari
• Format: Article
• Language: English
• Subjects: Ascomycetes; Basidiomycetes; Biodiversity; Biomedical and Life Sciences; Biotechnology; Endophytes; Epichloe festucae; Festuca rubra; Grasses; Life Sciences; Meadows; Medical Microbiology; Metabolites; Microbial Ecology; Microbiology; Mycology; Plant Physiology; River banks; Taxa
• ISSN: 1560-2745; 1878-9129
• DOI: 10.1007/s13225-013-0233-x

Epichloë festucae is an endophytic fungus that infects systemically the aerial tissues of the host grass Festuca rubra . This fungus is transmitted vertically from the mother plant to seeds. Hypothetically, the presence of E. festucae could affect the infection of a plant by other fungal species. This could occur if E. festucae metabolites produced in planta interfere negatively with other fungal infections; or alternatively, if the modulation of plant defenses by the endophyte favour further fungal infections. We have analyzed the presence of culturable non-systemic endophytes in plants of F. rubra infected (E+) and not infected (E−) by E. festucae in two subarctic habitats, meadows and riverbanks in Northern Finland. The observed non-systemic endophyte infection frequencies were similar among E+ and E− plants from riverbanks, and E+ plants from meadows. In contrast to these, the infection frequency was significantly lower in E− plants from meadows. This result suggests that the presence of E. festucae is not a main factor determining the presence of non-systemic endophytes in plants. Instead, plant genetic characteristics related to compatibility with E. festucae and other endophytes in the more stable meadow populations might play a role in these fungus–fungus–plant interactions. As a result of the survey, 18 different taxa of non-systemic endophytes were identified in plants of F. rubra . All were ascomycetes except for one basidiomycete. Three endophytic taxa could not be ascribed to a genus, but sequence data indicated that they were conspecific with other unidentified endophytes that have been isolated in cold biomes at different locations.