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ABSTRACT Mite–plant defense mutualisms are among the most common defense mutualisms in the world—yet studies providing basic information on their prevalence in plant communities remain rare. Here, we systematically surveyed common woody plants in a North American deciduous forest for the presence of plant–mite mutualistic interactions. We scored 16 common woody species in a wooded natural area for the presence and number of mite domatia—small structures on the underside of plant leaves that are known to house mutualistic mites. We found that 80% of common woody species in the forest had mite domatia, the highest reported percentage of mite domatia in any survey conducted thus far. We paired our survey with a quantification of the number of mites found on each leaf and investigated the relationship between mite domatia and mite abundance within and across species. We found that plants with mite domatia had significantly more mites on their leaves than species that lacked mite domatia, and that plants with more domatia had more mites. Together, our study provides much needed systematic survey data on plant–mite mutualism prevalence in an important plant community and points to northern temperate forests as a promising system to study plant–mite mutualisms in high densities in the future.
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This content will become publicly available on June 12, 2027
Micromorphology and chemistry of mite domatia: mutualistic trait convergence and variation across eight sympatric north American species
Abstract Mite domatia — small structures on plant leaves that house mutualistic mites — are widespread across plants yet remain relatively understudied. Here we investigate the chemistry and micromorphology of mite domatia across sympatric species of broadleaf deciduous woody species that have convergently evolved tuft-form mite domatia. Specifically, we test whether domatia display similar micromorphological and chemical properties using metabolomics and scanning electron microscopy across multiple independent sympatric lineages. To identify domatia-specific phenotypes, we also compare tissue within domatia to that of nearby leaf tissue on each of the four domatium-bearing species, and test whether species with domatia exhibit reduced chemical defense relative to species that lack domatia using four additional species that lack prominent domatia as a control. We found that domatium-bearing species had significantly lower total phenolic concentrations and lower total defense compound abundance compared to control species, consistent with an evolutionary trade-off between chemical and mutualistic defense. However, within leaves, domatium tissue chemical defense did not differ from surrounding laminar tissue. In contrast, trichome morphology showed clear convergent modification: domatium trichomes were 24–31% longer than trichomes elsewhere on the leaf, a pattern reversed in control species. Together, our findings shed light on the degree of phenotypic convergence in a widespread, ecologically important trait.
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- Award ID(s):
- 2236747
- PAR ID:
- 10704164
- Publisher / Repository:
- Symbiosis
- Date Published:
- Journal Name:
- Symbiosis
- ISSN:
- 0334-5114
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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