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Abstract A paradigm in the plant defence literature is that defending against herbivores comes at a cost to growth, resulting in a growth–defence trade‐off. However, while there is strong evidence for growth–defence trade‐offs across species, evidence is mixed within species.Several mechanisms can account for this equivocal support within species, but teasing them apart requires examining growth–defence relationships both within and among populations, an approach seldom employed.We examined correlations between plant biomass (growth) and terpene production (defence) within and among populations ofMonarda fistulosa, a perennial herb. We sampled populations from Montana and Wisconsin, regions that differ in resource availability characterized by different summer precipitation and associated abiotic conditions that influence plant productivity.We found negative, neutral and positive growth–defence correlations, depending on the scale examined. Negative correlations occurred across populations originating from divergent regions, positive correlations occurred across populations originating from within the high‐resource region and neutral correlations were found within single populations.Collectively, these results challenge the general expectation of ubiquitous trade‐offs and support emerging views that resource availability (as it affects productivity) shapes the evolution of defence at different scales. A freePlain Language Summarycan be found within the Supporting Information of this article.
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This content will become publicly available on August 19, 2025
Biomimetic laser-induced graphene fern leaf and enzymatic biosensor for pesticide spray collection and monitoring
Monitoring of pesticide concentration distribution across farm fields is crucial to ensure precise and efficient application while preventing overuse or untreated areas.
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- Award ID(s):
- 2037026
- PAR ID:
- 10560121
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- Nanoscale Horizons
- Volume:
- 9
- Issue:
- 9
- ISSN:
- 2055-6756
- Page Range / eLocation ID:
- 1543 to 1556
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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