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Title: Habitat‐adapted microbial communities mediate Sphagnum peatmoss resilience to warming
Summary

Sphagnumpeatmosses are fundamental members of peatland ecosystems, where they contribute to the uptake and long‐term storage of atmospheric carbon. Warming threatensSphagnummosses and is known to alter the composition of their associated microbiome. Here, we use a microbiome transfer approach to test if microbiome thermal origin influences host plant thermotolerance.

We leveraged an experimental whole‐ecosystem warming study to collect field‐grownSphagnum, mechanically separate the associated microbiome and then transfer onto germ‐free laboratorySphagnumfor temperature experiments. Host and microbiome dynamics were assessed with growth analysis, Chlafluorescence imaging, metagenomics, metatranscriptomics and 16S rDNA profiling.

Microbiomes originating from warming field conditions imparted enhanced thermotolerance and growth recovery at elevated temperatures. Metagenome and metatranscriptome analyses revealed that warming altered microbial community structure in a manner that induced the plant heat shock response, especially the HSP70 family and jasmonic acid production. The heat shock response was induced even without warming treatment in the laboratory, suggesting that the warm‐microbiome isolated from the field provided the host plant with thermal preconditioning.

Our results demonstrate that microbes, which respond rapidly to temperature alterations, can play key roles in host plant growth response to rapidly changing environments.

 
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Award ID(s):
1737899
NSF-PAR ID:
10367647
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
234
Issue:
6
ISSN:
0028-646X
Page Range / eLocation ID:
p. 2111-2125
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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