Herbicides act as human-mediated novel selective agents and community disruptors, yet their full effects on eco-evolutionary dynamics in natural communities has only begun to be appreciated. Here we synthesize how herbicide exposures can result in dramatic phenotypic and compositional shifts within communities at the agro-ecological interface and how these in turn affect species interactions and drive plant (and plant-associates’) evolution in ways that can feedback to continue to affect the ecology and ecosystem functions of these assemblages. We advocate a holistic approach to understanding these dynamics that includes plastic changes and plant community transformations and also extends beyond this single trophic level targeted by herbicides to the effects on non-target plant-associated organisms and their potential to evolve, thereby embracing the complexity of these real-world systems. We make explicit recommendations for future research to achieve this goal and specifically address impacts of ecology on evolution, evolution on ecology, and their feedbacks so that we can gain a more predictive view of the fates of herbicide-impacted communities.
This content will become publicly available on November 23, 2023
Interspecific variation in resistance and tolerance to herbicide drift reveals potential consequences for plant community coflowering interactions and structure at the agro-eco interface
Abstract Background and Aims When plant communities are exposed to herbicide ‘drift’, wherein particles containing the active ingredient travel off-target, interspecific variation in resistance or tolerance may scale up to affect community dynamics. In turn, these alterations could threaten the diversity and stability of agro-ecosystems. We investigated the effects of herbicide drift on the growth and reproduction of 25 wild plant species to make predictions about the consequences of drift exposure on plant-plant interactions and the broader ecological community. Methods We exposed potted plants from species that commonly occur in agricultural areas to a drift-level dose of the widely used herbicide dicamba or a control solution in the glasshouse. We evaluated species-level variation in resistance and tolerance for vegetative and floral traits. We assessed community-level impacts of drift by comparing species evenness and flowering networks of glasshouse synthetic communities comprised of drift-exposed and control plants. Key Results Species varied significantly in resistance and tolerance to dicamba drift: some were negatively impacted while others showed overcompensatory responses. Species also differed in the way they deployed flowers over time following drift exposure. While drift had negligeable effects on community evenness based on vegetative biomass, it caused salient differences in the structure of more »
- Award ID(s):
- 1834688
- Publication Date:
- NSF-PAR ID:
- 10386940
- Journal Name:
- Annals of Botany
- ISSN:
- 0305-7364
- Sponsoring Org:
- National Science Foundation
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