EFFECTS OF FUNGAL ENDOPHYTES ON INTERSPECIFIC AND INTRASPECIFIC COMPETITION IN THE GRASSES FESTUCA-ARUNDINACEA AND LOLIUM-PERENNE

(1) This study examined interspecific and intraspecific competition between plants either infected or uninfected with a fungal endophyte. The two species used, tall fescue (Festuca arundinacea Schreb.) and perennial rye-grass (Lolium perenne L.), were grown at several densities and combinations in three greenhouse experiments. (2) In general, endophyte infection enhanced the competitive ability of tall fescue; in contrast, uninfected plants of perennial rye-grass performed better than infected plants under both interspecific and intraspecific competition. (3) The results suggest that the presence or absence of fungal endophytes could be an important determinant of competition success of grass species in grasslands.