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

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Ecological interactions between plants and insects are of paramount importance for the maintenance of biodiversity and ecosystem functioning. Herbicides have long been considered a threat to plant and insect populations, but global increases in intensive agriculture and availability of herbicide-resistant crops have intensified concerns about their full impact on biodiversity. Here, we argue that exposure to sublethal herbicide doses has the potential to alter plant-insect interactions as a result of disruptions in their chemical communication. This is because herbicides interfere with biosynthetic pathways and phytohormones involved in the production of several classes of plant volatiles that mediate plant-insect chemical communication. Sublethal herbicide doses can modify the morphological and life-history plant traits and affect interactions with insects. However, the potential changes in plant volatiles and their consequences for plant-insect chemical communication have not yet received as much attention. We discuss how target-site (disruptors of primary metabolism) and non-target-site (synthetic auxins) herbicides could alter the production of plant volatiles and disrupt plant-insect chemical communication. We suggest research avenues to fill in the current gap in our knowledge that might derive recommendations and applied solutions to minimize herbicides' impacts on plant-insect interactions and biodiversity.

Societal Impact Statement The practice of writing science blogs benefits both the scientist and society alike by providing professional development opportunities and delivering information in a format that is accessible to large and diverse audiences. By designing a project that introduced upper‐level undergraduate students to science blog writing with a focus on plant biology, we piqued students' interest in science writing and the content of a popular plant science blog website. If adopted more widely, this work could broaden the scope of science education and promote the development of effective science communication skills for the next generation of scientists. Summary Successful scientists must communicate their research to broad audiences, including distilling key scientific concepts for the general public. Students pursuing careers in Science, Technology, Engineering, and Mathematics (STEM) fields benefit from developing public communication skills early in their careers, but opportunities are limited in traditional biology curricula. We created the “Plant Science Blogging Project” for a Plant Biology undergraduate course at the University of Pittsburgh in Fall 2018 and 2019. Students wrote blog posts merging personal connections with plants with plant biology concepts for the popular science blogs Plant Love Stories and EvoBites. By weaving biology into their narratives, students learned how to share botanical knowledge with the general public. The project had positive impacts on student learning and public engagement. In post‐assignment surveys, the majority of students reported that they enjoyed the assignment, felt it improved their understanding of plant biology, and piqued their interest in reading and writing science blogs in the future. Approximately one‐third of the student‐authored blogs were published, including two that rose to the top 10 most‐read posts on Plant Love Stories. Some dominant themes in student blogs, including medicine and culture, differed from common story themes published on the web, indicating the potential for students to diversify science blog content. Overall, the Plant Science Blogging Project allows undergraduate students to engage with plant biology topics in a new way, sharpen their scientific communication skills in accordance with today's world of mass information sharing, and contribute to the spread of scientific knowledge for public benefit.

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 coflowering networks within communities. Drift reduced the degree and intensity of flowering overlap among species, altered the composition of groups of species that were more likely to coflower with each other than with others, and shifted species roles (e.g., from dominant to inferior floral producers and vice versa). Conclusions These results demonstrate that even low levels of herbicide exposure can significantly alter plant growth and reproduction, particularly flowering phenology. If field-grown plants respond similarly, then these changes would likely impact plant-plant competitive dynamics and potentially plant-pollinator interactions occurring within plant communities at the agro-ecological interface.