Kruti Shukla, Heather A. Hager, Kathryn A. Yurkonis and Jonathan A. Newman
We investigated the generality of the grass-fungal endophyte work on host invasiveness, which has mostly involved studies of Schedonorus arundinaceus–Epichloë coenophiala, by studying a pair of closely related species, S. pratensis and E. uncinata. Grass abundance, endophyte infection rate, and the co-occurring vegetation were sampled 3, 4, 5, and 6 years, and aboveground invertebrate community 3 and 4 years, after cultivars with different levels of endophyte infection were experimentally seeded into an old-field habitat. Contrary to expectations, endophyte infection did not enable the grass to achieve high abundance in the plant community, and high-endophyte S. pratensis increased plant species richness. However, high-endophyte S. pratensis marginally decreased invertebrate taxon richness relative to low-endophyte cultivars. Our results suggest that the effect of the grass-fungal symbiosis on diversity is specific to species, cultivar, infection, and potentially site.