A trait‐based framework linking the soil metabolome to plant–soil feedbacks

Abstract

SummaryBy modifying the biotic and abiotic properties of the soil, plants create soil legacies that can affect vegetation dynamics through plant–soil feedbacks (PSF). PSF are generally attributed to reciprocal effects of plants and soil biota, but these interactions can also drive changes in the identity, diversity and abundance of soil metabolites, leading to more or less persistent soil chemical legacies whose role in mediating PSF has rarely been considered. These chemical legacies may interact with microbial or nutrient legacies to affect species coexistence. Given the ecological importance of chemical interactions between plants and other organisms, a better understanding of soil chemical legacies is needed in community ecology. In this Viewpoint, we aim to: highlight the importance of belowground chemical interactions for PSF; define and integrate soil chemical legacies into PSF research by clarifying how the soil metabolome can contribute to PSF; discuss how functional traits can help predict these plant–soil interactions; propose an experimental approach to quantify plant responses to the soil solution metabolome; and describe a testable framework relying on root economics and seed dispersal traits to predict how plant species affect the soil metabolome and how they could respond to soil chemical legacies.

Neighbour-induced changes in root exudation patterns of buckwheat results in altered root architecture of redroot pigweed

“…Buckwheat may be recognizing other buckwheat or redroot pigweed neighbours (e.g., through the highlighted species-specific compounds) and responding to their unique cues. Species-specific soil chemical legacies also affect the vegetation composition and dynamics through plant-soil feedback effects 74 . Studies show that negative feedback in wheat result in the release of secondary metabolites of the family of the benzoxazinoids 75 .…”

If you can’t beat them, join them: using invasive plants to understand rhizodeposits as drivers of plant-soil feedbacks

“…Evidence suggests that invasive or other competitive plants invest more resources towards recruiting and supporting beneficial microbes in the rhizosphere compared to native plants (Kasťovskáet al, 2015;Yu et al, 2022), and when invasive plants alter the soil microbiome it often promotes invader success (Coats and Rumpho, 2014). Ultimately, invasive plant species can restructure the soil microbial community in ways that facilitate invasions, and these feedback loops are likely driven by their exudate and rhizodeposit profiles (Delory et al, 2023).…”