Floral nectar contains microbes that can influence nectar chemistry and pollinator visitation, and these microbial communities can be affected by pollinators in turn. Some flowers are also visited by nectar robbers, which feed on nectar through holes cut in floral tissue. If nectar robbers alter nectar microbial communities, they might have unexpected impacts on pollinator visitation. We investigated whether robbing could affect nectar microbial communities directly, by introducing microbes, or indirectly, by triggering a plant response to floral damage. We applied four treatments to flowers of
- PAR ID:
- 10252205
- Date Published:
- Journal Name:
- Annual Review of Ecology, Evolution, and Systematics
- Volume:
- 51
- Issue:
- 1
- ISSN:
- 1543-592X
- Page Range / eLocation ID:
- 363 to 386
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Floral nectar, an important resource for pollinators, is inhabited by microbes such as yeasts and bacteria, which have been shown to influence pollinator preference. Dynamic and complex plant-pollinator-microbe interactions are likely to be affected by a rapidly changing climate, as each player has their own optimal growth temperatures and phenological responses to environmental triggers, such as temperature. To understand how warming due to climate change is influencing nectar microbial communities, we incubated a natural nectar microbial community at different temperatures and assessed the subsequent nectar chemistry and preference of the common eastern bumble bee, Bombus impatiens . The microbial community in floral nectar is often species-poor, and the cultured Brassica rapa nectar community was dominated by the bacterium Fructobacillus . Temperature increased the abundance of bacteria in the warmer treatment. Bumble bees preferred nectar inoculated with microbes, but only at the lower, ambient temperature. Warming therefore induced an increase in bacterial abundance which altered nectar sugars and led to significant differences in pollinator preference.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1146/annurev-ecolsys-011720-013401
