Role of endophytic fungi in grass litter decomposition

Fungal endophytes of grasses affect ecosystem processes through mutualistic interactions with host plants, but how grass endophytes affect litter decomposition remains unclear. In this study, previously published data on litter quality and decomposition of grasses are summarised and effects of fungal endophytes of grasses on litter quality and decomposition are reviewed to discuss possible roles of endophytes in decomposition. Aboveground litters of grasses have relatively low nitrogen (N) and lignin contents and show slow increase of N and lignin contents during decomposition. Endophyte-infected litter have slightly lower N contents than non-infected litter, but the differences so far reported were not statistically significant. A negative effect of grass endophytes on litter decomposition rates was demonstrated, but the effect of endophyte infection on decomposition was not as strong as the effects of other biological and environmental factors. This suggests that grass endophytes have a relatively minor effect of on litter quality and decomposition, but more studies are necessary to verify this tentative conclusion. Keywords: decomposition, lignin, litter, nitrogen