The Editor’s Choice article for issue for Volume 106 Issue 6 is a study by Wooliver et al. about the role fungi plays in the variation of plant responses to nitrogen enrichment. Senior Editor Amy Austin has taken a closer look at the paper in the blog post below…
Nitrogen deposition generated by human activities (industry, livestock farming, agriculture) is of considerable concern for the potential negative effects on existing biodiversity, ecosystem functioning and ecosystem services in many terrestrial ecosystems (Galloway et al., 2008).
One of the most difficult aspects of mitigating or reducing this contamination is the non-point source nature of N deposition, which often affects natural or undisturbed natural ecosystems that are adjacent to areas of human activity. While considerable attention has been focused on plant responses to these exogenous N (Janssens et al. 2010), the broad range of plant-microbial interactions are still very much unknown in terms of what can happen to the ecological complexity of other organisms interacting with plants.
The Editor’s Choice from this issue, literally and figuratively, goes ´down under´ — focusing on what is happening belowground with free-living fungi and mycorrhizae, in 15 eucalypt species from Tasmania, Australia. Rachel Wooliver and colleagues used a greenhouse experiment to test how soil conditioning would affect plant response to N enrichment across a subgenus of eucalypts known as Symphomytrus, which contains some of the best known eucalpyt species such as blue gums.
The authors found that soil fungi play a surprisingly important role in dictating aboveground responses to N enrichment. One lineage of eucalypts, which reduced their investment in ectomycorrhizal (ECM) fungal relationships, responded more to N enrichment than their congeneric species, who maintained their ECM symbioses (and hence their carbon investment). The implications of this, and one of the novel insights of this study, is that the phylogenetic relationships observed in previous work by these authors with respect to increased N (Wooliver et al. 2017) may be ultimately driven by the response of their symbionts to N enrichment, and the relative carbon investment that the plants make in maintaining these symbioses.
Next stop is the field! We look forward to seeing further experiments under natural conditions to see if these patterns established in controlled conditions are generalizable to the complexity of the natural world. Stay tuned!
Amy Austin, Senior Editor, Journal of Ecology
Read the new issue of Journal of Ecology online. Read the Editor’s Choice paper: Soil fungi underlie a phylogenetic pattern in plant growth responses to nitrogen enrichment