Fungal endophytes decrease aphid performance in grasses: effects on virus transmission?

We examined how endophyte infection and nutrient availability affects the performance of bird-cherry aphid (Rhopalosiphum padi) in meadow fescue (Festuca pratensis). Endophyte infection drastically reduced aphid survival and reproduction in our study

Genetic Compatibility Determines Endophyte-Grass Combinations

Even highly mutually beneficial microbial-plant interactions, such as mycorrhizal- and rhizobial-plant exchanges, involve selfishness, cheating and power-struggles between the partners, which depending on prevailing selective pressures, lead to a continuum of interactions from antagonistic to mutualistic. Using manipulated grass-endophyte combinations in a five year common garden experiment, we show that grass genotypes and genetic mismatches constrain genetic combinations between the vertically (via host seeds) transmitted endophytes and the out-crossing host, thereby reducing infections in established grass populations. Infections were lost in both grass tillers and seedlings in F1 and F2 generations, respectively. Experimental plants were collected as seeds from two different environments, i.e., meadows and nearby riverbanks. Endophyte-related benefits to the host included an increased number of inflorescences, but only in meadow plants and not until the last growing season of the experiment. Our results illustrate the importance of genetic host specificity and trans-generational maternal effects on the genetic structure of a host population, which act as destabilizing forces in endophyte-grass symbioses. We propose that (1) genetic mismatches may act as a buffering mechanism against highly competitive endophyte-grass genotype combinations threatening the biodiversity of grassland communities and (2) these mismatches should be acknowledged, particularly in breeding programmes aimed at harnessing systemic and heritable endophytes to improve the agriculturally valuable characteristics of cultivars

No effects of Epichloë endophyte infection on nitrogen cycling in meadow fescue (Schedonorus pratensis) grassland

Peer reviewe

Grass endophytes in diet protect sibling voles from least weasel predation

In this study, we first examined how feeding on Neotyphodium endophyte infected (E+) or endophyte free (E-) meadow ryegrass (Scherodonus pratensis) affects body mass and reproduction of sibling voles (Microtus levis), and then whether diet mediates the vulnerability of voles to least weasel (Mustela nivalis nivalis) predation

Foraging Preferences of Barnacle Geese on Endophytic Tall and Red Fescues

Many grasses (Poaceae) have symbiotic fungal endophytes, which affect livestock by producing unpalatable or harmful secondary compounds. Less is known about the repelling effects of fungal endophytes on avian grazers despite potential wildlife management implications. Herbivorous goose (Branta spp.) species may become a nuisance in recreational use areas via fecal littering. Planting these areas with grasses that avian grazers avoid may help mitigate this damage. In 2016, we studied the foraging preference of the barnacle geese (B. leucopsis) with endophytic (E+) or endophyte-free (E-) red fescue (Festuca rubra) and/or tall fescue (Schedonorus phoenix) in 2 sites in Finland that had a history of nuisance geese damage. In the high grazing pressure site, we planted both grass species, while in the low grazing pressure site only tall fescue was used. Geese preference was measured as the percentage of the area grazed, the height of the residual grass grazed, and the number of fecal droppings in the grass plots. Geese foraging did not differ between E- and E+ grasses, but red fescues were preferred over tall fescues. This supports previous findings that tall fescues or other coarse species could reduce the attractiveness of recreational areas to geese

Endophytic Epichloe species and their grass hosts: from evolution to applications

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Glyphosate-Modulated Biosynthesis Driving Plant Defense and Species Interactions

Glyphosate has become the best-selling herbicide used in agriculture, horticulture,silviculture, and urban environments. It disrupts the shikimate metabolicpathway and thereby blocks the production of aromatic amino acids, which arethe basis for several plant metabolites. Glyphosate residues are reported insoils from diverse environments, but the effects on plant physiology and consequencesfor species interactions are largely unknown. Here, we emphasize thecomplexity of these physiological processes, and argue that glyphosate residuesmodulate biosynthetic pathways, individually or interactively, which may affectinteractions between plants and heterotrophic organisms. In this way, glyphosateresidues can substantially interfere with plant resistance and the attractionof beneficial insects, both of which are essential elements in integrated pestmanagement and healthy ecosystems.</p

Toward Comprehensive Plant Microbiome Research

Microbes have driven eco-evolutionary adaptations organizing biodiversity from the origin of life. They are ubiquitous and abundant, facilitating the biochemical processes that make Earth habitable and shape ecosystem structures, functions, and services. Recent studies reveal that commensalistic and beneficial microbes associated with wild and domesticated plants may aid in establishing sustainable agriculture for a changing climate. However, developing microbe-based biotechnologies and ecosystem services requires a thorough understanding of the diversity and complexity of microbial interactions with each other and with higher organisms. We discuss the hot and blind spots in contemporary research on plant microbiomes, and how the latest molecular biological techniques and empirical eco-evolutionary approaches could elevate our perception of microbe-plant interactions through multidisciplinary studies

Silicon, endophytes and secondary metabolites as grass defenses against mammalian herbivores

Article Accepted Date: 30 August 2014 Acknowledgments This study was supported by the Academy of Finland (grant no. 133495 to Otso Huitu; grants no. 137909 and 110658 to Kari Saikkonen) and by the NERC (grant no. NE/F003994/1 to Xavier Lambin). We thank Dr. Stefan Reidinger and Dr. James Stockdale for help with the silicon analyses. Technician Sinikka Sorsa conducted the phenolic extractions. Stephen Ryan and Anaïs Zimmer assisted with field work.Peer reviewedPublisher PD