Diversity and distribution of Neotyphodium-infected grasses in Argentina

In the present work, we studied the presence of "epichloë/neotyphodium endophytes" in native grasses from Argentina. An extensive area of this country, representative of several different environments, was studied. Nine new host species of the genera Briza, Bromus and Poa were observed to be infected with asexual seed-borne endophytes. Epichloë stromata were not observed on any grass species. The incidence of infection in natural populations was highly variable among host species and among populations of the same host species. Morphological characterization revealed differences among the endophytes of different host species and among endophytes of different populations of the same host species. We also summarize the previous knowledge and present unpublished data on host diversity and distribution of these fungi in Argentina. Our results are discussed and compared with previous studies on endophytes in Argentina. This work supports the hypothesis that sexual species (Epichloë) are not present in the southern hemisphere, and suggests the existence of a high diversity of asexual endophytes in South America.