The presence of a foreign microbial community promotes plant growth and reduces filtering of root fungi in the arctic-alpine plant Silene acaulis

ABSTRACT

Background

Climate change is expected to drive trailing-edge range redistributions of arctic-alpine plant populations, bringing together immigrant plant ecotypes and soil microbial communities associated with already resident ecotypes.

Aims

The goal of the present study was to assess growth performance and plant–microbe interactions between seedlings and native and foreign microbial communities in ecotypes of the cushion plant Silene acaulis from Europe and North America.

Methods

Using seed sourced from Colorado, USA, and Ireland we grew Silene seedlings in sterile bulk soil with live inocula added from their own local soil and each other’s soil. We measured above-ground plant growth metrics, and analysed fungal and bacterial community composition using marker gene sequencing and microscopy.

Results

Seedlings growing in foreign soil inocula showed significantly greater biomass or shoot length compared to growth in home soil inocula. While seedling root microbiomes were overall convergent with each other compared to source soil inocula, significantly lower filtering of fungal taxa from the soil was observed for seedlings growing in foreign compared to home soil inocula.

Conclusions

Foreign plant ecotypes from distant habitats may experience competitively beneficial effects when growing in local soil communities; however, the nature and generality of these interactions requires further analysis.

KEYWORDS:

• Bacteria
• endophytes
• filtering
• fungi
• plant-microbe interactions

Acknowledgements

We thank Harry Kranichfeld and Elise Castle for help in the greenhouse and lab. This project was funded by National Science Foundation grant DEB 1457827 to KNS and SKS. CM was funded by the 2016-2017 Fulbright International Visiting Scholar program [Fulbright-EPA Irish Scholar Award,  Project No: 2016-CCRP-FS.26]. We thank the University of Colorado Mountain Research Station and Niwot Ridge Long-Term Ecological Research Program (National Science Foundation grant DEB 1637686) for logistical support. We thank Tom Lemieux, Janice Harvey, and Tess Additon at the University of Colorado greenhouse for assistance. We thank five anonymous reviewers for helpful feedback on this manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplemental data for this article can be accessed here.

Additional information

Funding

This work was supported by the National Science Foundation Division of Environmental Biology [1457827,1637686]; US-Ireland Fulbright Commission [Fulbright-EPA Irish Scholar Award,  Project No: 2016-CCRP-FS.26].

Notes on contributors

Conor V. Meade

Conor V. Meade is a professor at Maynooth University. Research in his lab group focuses plant molecular ecology and the phylogeography of arctic-alpine and tropical plants.

Clifton P. Bueno de Mesquita

Clifton P. Bueno de Mesquita is a postdoctoral scholar at the University of Colorado. His dissertation work focused on plant-microbe interactions in the alpine in the context of climate change.

Steven K. Schmidt

Katharine N. Suding is a professor at the University of Colorado. Research in her lab group focuses on restoration ecology, community ecology, trait-based ecology, and responses to global change.

Katharine N. Suding

Steven K. Schmidt is a professor at the University of Colorado. Research in his lab group focuses on the microbial ecology of high elevation and high latitude ecosystems.