Conversion of inorganic nitrogen by mutualistic nitrogen-fixing bacteria is essential for plant growth and reproduction, as well as the development of chemical and mechanical defenses. It is unclear, however, how these bacteria alter cooccurring symbioses at higher trophic levels; e.g., extrafloral nectary (EFN) induction, in response to herbivory, to attract defensive mutualists. We hypothesized that plants colonized by nitrogen-fixing bacteria would mount a larger inducible, defensive response than plants lacking symbioses, as defensive traits are costly. We predicted that bean plants, Vicia faba L., harboring Rhizobium leguminosarum bv. viciae Frank would produce more EFNs upon leaf damage, than plants lacking the symbionts, as EFN induction in V. faba is resource-dependent. Here we report that V. faba colonized by R. leguminosarum produced similar numbers of EFNs as did plants without symbionts. Plants with symbionts, however, produced significantly fewer EFNs over 1 week in response to leaf damage, than those without leaf damage. As such, nitrogen-fixing bacteria may not always benefit the host plant, but rather, the utility of these bacteria may be dependent on the prevailing ecological conditions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.