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

Abstract

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.

Editorial special issue: soil, plants and endophytes

“…This suggests that the Epichloid may not decrease the benefit of the endophyte-grass symbiosis by reducing soil fertility. Soto-Barajas et al (2016) using several Epichloë endophytes and Lolium perenne showed also that endophyte-infected plants had significantly lower P, Ca, S, B, neutral detergent fiber and lignin contents, and higher Mn and digestibility than non-inoculated plants, independently of the plant origin. Biomass production was not affected by endophytes but by the plant origin.…”

“…Soussi et al (2016) provided a comprehensive overview of the microbial diversity in arid lands and deserts versus specific microbial assemblages associated with the endosphere of plants. Discussion about the drivers shaping the endophytic diversity, on how plant-associated microbiomes are selected, and on their biotechnological potential was well provided.…”

A fungal endophyte of a palatable grass affects preference of large herbivores

“…populations infected with E. occultans exhibit peramines (Sugawara et al 2006), N-acetylnorlolines and N-formyllolines (Moore et al 2015) in variable concentrations according to plant organs, phenological stage and geographical origin. As documented for domestic herbivores consuming other grass species (Oliveira et al 2004;Zabalgogeazcoa et al 2006;Soto-Barajas et al 2016), patterns of plant nutritional values and digestibility associated with endophyte presence in L. multiflorum might influence animal preference. Nevertheless, in addition to fungal alkaloids, several studies suggest that epichloid endophytes may exert further ecophysiological and metabolomic effects (e.g.…”

“…We analysed those traits usually affecting preference by domestic herbivores (Bailey et al 1996;Jung et al 1997) that, in turn, can be also modified by the endophyte (Miranda et al 2011;Soto-Barajas et al 2016). We analysed those traits usually affecting preference by domestic herbivores (Bailey et al 1996;Jung et al 1997) that, in turn, can be also modified by the endophyte (Miranda et al 2011;Soto-Barajas et al 2016).…”

“…different silica absorption, flavonoid and volatile compound synthesis, lignin concentration) with potential impacts on herbivores' preference (Rasmussen et al 2008(Rasmussen et al , 2009Huitu et al 2014;Li et al 2014;Dupont et al 2015). As documented for domestic herbivores consuming other grass species (Oliveira et al 2004;Zabalgogeazcoa et al 2006;Soto-Barajas et al 2016), patterns of plant nutritional values and digestibility associated with endophyte presence in L. multiflorum might influence animal preference.…”