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ABSTRACT Plant–microbe associations are ubiquitous, but parsing contributions of dispersal, host filtering, competition and temperature on microbial community composition is challenging. Floral nectar‐inhabiting microbes, which can influence flowering plant health and pollination, offer a tractable system to disentangle community assembly processes. We inoculated a synthetic community of yeasts and bacteria into nectars of 31 plant species while excluding pollinators. We monitored weather and, after 24 h, collected and cultured communities. We found a strong signature of plant species on resulting microbial abundance and community composition, in part explained by plant phylogeny and nectar peroxide content, but not floral morphology. Increasing temperature reduced microbial diversity, while higher minimum temperatures increased growth, suggesting complex ecological effects of temperature. Consistent nectar microbial communities within plant species could enable plant or pollinator adaptation. Our work supports the roles of host identity, traits and temperature in microbial community assembly, and indicates diversity–productivity relationships within host‐associated microbiomes.
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This content will become publicly available on May 1, 2026
In the nectar, there are answers: exploring the intersection of colored nectars and reactive oxygen species in manipulating pollinator behavior
Summary Nectar, a vital mediator of plant–pollinator interactions, exhibits remarkable chemical diversity beyond sugars, including reactive oxygen species and specialized metabolites such as pigments. Colored nectars, present in over 70 species, function as visual signals, inhibitors of microbial growth, or nutritional rewards, underscoring their ecological importance. Reactive oxygen species contribute to pigment formation and nectar stability, highlighting their dual roles in nectar chemistry and defense. Advances in analytical techniques and interdisciplinary research have highlighted the complex interplay between nectar composition, pollinator behavior, and microbial communities, emphasizing nectar's multifaceted roles in plant fitness and ecosystem dynamics.
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- Award ID(s):
- 2025297
- PAR ID:
- 10655514
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 246
- Issue:
- 3
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- 901 to 910
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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