Floral nectar is frequently colonised by microbes. However, nectar microbial communities are typically species‐poor and dominated by few cosmopolitan genera. One hypothesis is that nectar constituents may act as environmental filters. We tested how five non‐sugar nectar compounds as well as elevated sugar impacted the growth of 12 fungal and bacterial species isolated from nectar, pollinators, and the environment. We hypothesised that nectar isolated microbes would have the least growth suppression. Additionally, to test if nectar compounds could affect the outcome of competition between microbes, we grew a subset of microbes in co‐culture across a subset of treatments. We found that some compounds such as H2O2suppressed microbial growth across many but not all microbes tested. Other compounds were more specialised in the microbes they impacted. As hypothesised, the nectar specialist yeast
This content will become publicly available on January 17, 2025
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
- NSF-PAR ID:
- 10487073
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Plant Species Biology
- ISSN:
- 0913-557X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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