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Summary Allelopathy is a common and important stressor that shapes plant communities and can alter soil microbiomes, yet little is known about the direct effects of allelochemical addition on bacterial and fungal communities or the potential for allelochemical‐selected microbiomes to mediate plant performance responses, especially in habitats naturally structured by allelopathy.Here, we present the first community‐wide investigation of microbial mediation of allelochemical effects on plant performance by testing how allelopathy affects soil microbiome structure and how these microbial changes impact germination and productivity across 13 plant species.The soil microbiome exhibited significant changes to ‘core’ bacterial and fungal taxa, bacterial composition, abundance of functionally important bacterial and fungal taxa, and predicted bacterial functional genes after the addition of the dominant allelochemical native to this habitat. Furthermore, plant performance was mediated by the allelochemical‐selected microbiome, with allelopathic inhibition of plant productivity moderately mitigated by the microbiome.Through our findings, we present a potential framework to understand the strength of plant–microbial interactions in the presence of environmental stressors, in which frequency of the ecological stress may be a key predictor of microbiome‐mediation strength.
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Microbiome‐mediated response to pulse fire disturbance outweighs the effects of fire legacy on plant performance
Summary Fire plays a major role in structuring plant communities across the globe. Interactions with soil microbes impact plant fitness, scaling up to influence plant populations and distributions. Here we present the first factorial manipulation of both fire and soil microbiome presence to investigate their interactive effects on plant performance across a suite of plant species with varying life history traits.We conducted fully factorial experiments on 11 species from the Florida scrub ecosystem to test plant performance responses to soils with varying fire histories (36 soil sources), the presence/absence of a microbiome, and exposure to an experimental burn.Results revealed interactive ‘pulse’ effects between fire and the soil microbiome on plant performance. On average, post‐fire soil microbiomes strongly reduced plant productivity compared to unburned or sterilized soils. Interestingly, longer‐term fire ‘legacy’ effects had minor impacts on plant performance and were unrelated to soil microbiomes.While pulse fire effects on plant–microbiome interactions are short‐term, they could have long‐term consequences for plant communities by establishing differential microbiome‐mediated priority effects during post‐disturbance succession. The prominence of pulse fire effects on plant–microbe interactions has even greater import due to expected increases in fire disturbances resulting from anthropogenic climate change.
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- Award ID(s):
- 1922521
- PAR ID:
- 10445870
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 233
- Issue:
- 5
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 2071-2082
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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