In Fungal Endophyte Symbiosis and Plant Diversity in Successional Fields, Clay and Holah aim to improve the understanding of the impact of endophyte infection within Tall fescue (Festuca arundinace) on biodiversity and succession. To do this, they seeded 8 20x20m plots of land with Tall fescue seeds, half of which had a high rate of infection form the Neotyphodium coenophialum endophyte. All plots were also seeded with forbs. To measure the biomass they harvested a transact on each plot after two months, dried them and weighed them. This was repeated twice a year and once on the last year for 4 years. They counted the plant species harvest to measure biodiversity. They found that the endophyte positive sites had a significantly lower species diversity than uninfected sites (22 to 27 species, respectively). The variation of the species diversity was initially due to the variation of the transacts selected and eventually the variance was largely explained by whether or not the plot had a high rate of endophyte infection. The biomass was similar for both infected and uninfected plots, with infected plots being marginally higher. the dominance of the Tall fescue increased in endophyte positive sites and decreased in endophyte negative sites. An explanation for the reduced diversity on infected sites may be due to the endophyte suppressing mycorrhizal association, which disables a symbiotic relationship in many plants. Other explanations include the endophytes toxin altering feeding behaviours of predators and improved drought tolerance increasing Tall fescues competitiveness
Applied Plant Ecology Winter 2020 