The effect of host community functional traits on plant disease risk varies along an elevational gradient
Abstract
Quantifying the relative impact of environmental conditions and host community structure on disease is one of the greatest challenges of the 21st century, as both climate and biodiversity are changing at unprecedented rates. Both increasing temperature and shifting host communities towards more fast-paced life-history strategies are predicted to increase disease, yet their independent and interactive effects on disease in natural communities remains unknown. Here, we address this challenge by surveying foliar disease symptoms in 220, 0.5 meter-diameter herbaceous plant communities along a 1100-meter elevational gradient. We find that increasing temperature associated with lower elevation can increase disease by (1) relaxing constraints on parasite growth and reproduction, (2) determining which host species are present in a given location, and (3) strengthening the positive effect of host community pace-of-life on disease. These results provide the first field evidence, under natural conditions, that environmental gradients can alter how host community structure affects disease.
Data availability
The data and code supporting the results are available on Figshare (DOI: 10.6084/m9.figshare.14058059) and Github (https://github.com/fhalliday/Calanda19)
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Calanda Biological Observatory 2019 field dataFigshare 10.6084/m9.figshare.14058059.
Article and author information
Author details
Funding
Academy of Finland (296686)
- Anna-Liisa Laine
European Research Council (724508)
- Anna-Liisa Laine
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Yuxin Chen, Xiamen University, China
Version history
- Received: February 8, 2021
- Accepted: May 10, 2021
- Accepted Manuscript published: May 13, 2021 (version 1)
- Version of Record published: June 16, 2021 (version 2)
Copyright
© 2021, Halliday et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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