Epichloë endophytes affect the nutrient and fiber content of Lolium perenne regardless of plant genotype

25 páginas, 2 figuras, 6 tablas[Background and Aims] Epichloë endophytes inhabit aerial grass tissues but they can modify belowground processes that might affect host nutrient balance. We aimed to determine the effects of endophyte status (E+=endophyte-infected; E−=non-infected) and three Epichloë morphotypes (M1,M2,M3) on growth and nutrient content of a heterogeneous set of naturally infected asymptomatic plants of Lolium perenne. In addition, plant parameters were compared between asymptomatic E+ and plants with choke disease.[Methods] A field experiment was conducted with 194 plants obtained from six natural populations (97E+, 97E−). For each E+ plant, the endophyte morphotype it hosted was known.[Results] Endophyte-infected plants had significantly lower P, Ca, S, B, neutral detergent fiber and lignin contents, and higher Mn and digestibility than E−, independently of plant origin. Biomass production was affected by plant origin but not by endophytes. No effect of Epichloë morphotypes in any parameter was found. However, asymptomatic E+ and choke diseased plants differed in nutrients, fibers, and digestibility.[Conclusions] An endophyte effect was detected in nutrient and fiber content, in spite of the heterogeneous constitution of the plant and fungal material used. The results obtained indicate that Epichloë may affect above and possibly underground processes involved in nutrient absorption, as well as plant quality, what may potentially affect litter decomposition processes.This research was financed with project AGL2011-22783 granted by the Spanish Ministry of Economy and Competitiveness. MC Soto-Barajas was supported by a CONACyT (Mexican Council of Sciences and Technology) doctoral fellowship. Thanks are due to Amador Alvarez for technical assistance with field experiment. Useful comments by two anonymous reviewers helped to improve a previous version of this manuscript.Peer reviewe