Foliar endophytic fungi: diversity in species and functions in forest ecosystems

As mycorrhizal fungi, endophytic fungi are ubiquitous in natural forest ecosystems. A great number of foliar endophytic fungi (FEFs) have been isolated from leaves of forest trees, and some metabolites are also isolated and characterized from the FEFs. These metabolites show strong potential to inhibit or kill insects and pathogenic fungi, especially those causing decline or damage of forest trees. In addition, FEFs can inhabit in leaf litter for a short or long period depending on endophytic species, thus they affect decomposition rate of leaf litter. Some FEFs can colonize in plant roots and promote plant growth. In the review, we provide an overview of the ecological roles of FEFs and hope the resources of FEFs can be developed and be used in forestry and agriculture to reduce use of insectcides and fungicides and in pharmacology to maintain human health.