Pollinator selection against toxic nectar as a key facilitator of a plant invasion
Citation:
P. A. Egan, P. C. Stevenson and J. C. Stout, Pollinator selection against toxic nectar as a key facilitator of a plant invasion, Philosophical Transactions of the Royal Society B: Biological Sciences, 2022, 377, 1853, 20210168Abstract:
Plant compounds associated with herbivore defence occur widely in floral nectar and can impact pollinator health. We showed previously that Rhododendron ponticum nectar contains grayanotoxin I (GTX I) at concentrations that are lethal or sublethal to honeybees and a solitary bee in the plant’s non-native range in Ireland. Here we further examined this conflict and tested the hypotheses that nectar GTX I is subject to negative pollinator-mediated selection in the non-native range– but that phenotypic linkage between GTX I levels in nectar and leaves acts as a constraint on independent evolution. We found that nectar GTX I experienced negative directional selection in the non-native range, in contrast to the native Iberian range, and that the magnitude and frequency of pollinator limitation indicated that selection was pollinator mediated. Surprisingly, nectar GTX I levels were decoupled from those of leaves in the non-native range, which may have assisted post-invasion evolution of nectar without compromising the anti-herbivore function of GTX I (here demonstrated in bioassays with an ecologically relevant herbivore). Our study emphasizes the centrality of pollinator health as a concept linked to the invasion process, and how post-invasion evolution can be targeted towards minimising lethal or sub-lethal effects on pollinators.
Sponsor
Grant Number
Science Foundation Ireland (SFI)
10/RFP/EOB2842
Author's Homepage:
http://people.tcd.ie/stoutjDescription:
PUBLISHED
Author: Stout, Jane
Type of material:
Journal ArticleCollections
Series/Report no:
Philosophical Transactions of the Royal Society B: Biological Sciences;377;
1853;
Availability:
Full text availableSubject (TCD):
Smart & Sustainable Planet , Biological Invasion , EVOLUTION , Evolution , Insects , POLLINATION , Pollination ecologyDOI:
10.1098/rstb.2021.0168Metadata
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