Impact of endophytic fungi on seed and seedling characteristics in tall and meadow fescues

Tall fescue and meadow fescue are naturally infected with fungal endophytes, Neotyphodium coenophialum and Neotyphodium uncinatum, respectively. Seed traits are an important measure of the effects of the endophytic fungi which has been less addressed. In this study we used endophyte-infected (EI) and endophyte-free (EF) clones of tall and meadow fescue genotypes in the field to investigate the effects of endophytes on seed production traits and subsequently on seed germination and seedling emergence. Endophyte infection increased the plant seed weight, the number of seeds per plant and the number of panicles per plant in both plant species. Seed germination was not affected by endophytes in tall fescue, while it was improved in endophyte-infected plants of meadow fescue. A negative endophyte effect was detectable for seedling emergence percentage and emergence rate of tall fescue, whereas EI plants of meadow fescue were positively affected by the endophyte for these characteristics. The better performance of EI plants for seed production traits may increase their relative fitness in populations and cause them to be more stable in different environmental conditions.