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Abstract Restoration of soil microbial communities, and microbial mutualists in particular, is increasingly recognized as critical for the successful restoration of grassland plant communities. Although the positive effects of restoring arbuscular mycorrhizal fungi during the restoration of these systems have been well documented, less is known about the potential importance of nitrogen‐fixing rhizobium bacteria, which associate with legume plant species that comprise an essential part of grassland plant communities, to restoration outcomes. In a series of greenhouse and field experiments, we examined the effects of disturbance on rhizobium communities, how plant interactions with these mutualists changed with disturbance, and whether rhizobia can be used to enhance the establishment of desirable native legume species in degraded grasslands. We found that agricultural disturbance alters rhizobium communities in ways that affect the growth and survival of legume species. Native legume species derived more benefit from interacting with rhizobia than did non‐native species, regardless of rhizobia disturbance history. Additionally, slow‐growing, long‐lived legume species received more benefits from associating with rhizobia from undisturbed native grasslands than from associating with rhizobia from more disturbed sites. Together, this suggests that native rhizobia may be key to enhancing the restoration success of legumes in disturbed habitats.
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This content will become publicly available on June 12, 2026
Rhizobia inoculation increases survival, flower production, herbivory, and pollinator visitation in an annual prairie legume
Native legumes are functionally important members of grasslands, but their reintroduction into degraded systems is limited by strong establishment filters. One of these establishment filters might be rhizobia limitation, where legume seedlings are unable to find suitable rhizobia symbionts in grasslands targeted for restoration. To test links between rhizobial inoculation and legume demographic parameters in a grassland restoration context, we evaluated how inoculation with rhizobia altered survival and seed production of a native annual legume (Chamaecrista fasciculata) inoculated with rhizobia and transplanted into a restored prairie. Small mammal herbivory was an important filter affecting survival ofC. fasciculatatransplants, with inoculated plants 81% more likely to be grazed than uninoculated plants. Despite this heavy grazing, plants inoculated with rhizobia survived transplantation 71% more often and, as a result, produced 82% more flowers, experienced 73% more visits by pollinators, and on average produced 220% more seeds. Our results indicate that although herbivory may also shape legume population establishment, at least in some years in some places, rhizobia could alterC. fasciculatainteractions with both herbivores and pollinators and improve population establishment.
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- Award ID(s):
- 1927671
- PAR ID:
- 10600480
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Restoration Ecology
- ISSN:
- 1061-2971
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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