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Abstract Despite the importance of insect pollination to produce marketable fruits, insect pollination management is limited by insufficient knowledge about key crop pollinator species. This lack of knowledge is due in part to (1) the extensive labour involved in collecting direct observations of pollen transport, (2) the variability of insect assemblages over space and time and (3) the possibility that pollinators may need access to wild plants as well as crop floral resources.We address these problems using strawberry in the United Kingdom as a case study. First, we compare two proxies for estimating pollinator importance: flower visits and pollen transport. Pollen‐transport data might provide a closer approximation of pollination service, but visitation data are less time‐consuming to collect. Second, we identify insectparametersthat are associated with high importance as pollinators, estimated using each of the proxies above. Third, we estimated insects' use of wild plants as well as the strawberry crop.Overall, pollinator importances estimated based on easier‐to‐collect visitation data were strongly correlated with importances estimated based on pollen loads. Both frameworks suggest that bees (ApisandBombus) and hoverflies (Eristalis) are likely to be key pollinators of strawberries, although visitation data underestimate the importance of bees.Moving beyond species identities, abundant, relatively specialised insects with long active periods are likely to provide more pollination services.Most insects visiting strawberry plants also carried pollen from wild plants, suggesting that pollinators need diverse floral resources.Identifying essential pollinators or pollinator parameters based on visitation data will reach the same general conclusions as those using pollen transport data, at least in monoculture crop systems. Managers may be able to enhance pollination service by preserving habitats surrounding crop fields to complement pollinators' diets and provide habitats for diverse life stages of wild pollinators.
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Characterizing each step of pollination in Phlox drummondii reveals that a single butterfly species predominates in the pollinator assemblage
Abstract PremiseA central goal of pollination biology is to connect plants with the identity of their pollinator(s). While predictions based on floral syndrome traits are extremely useful, direct observation can reveal further details of a species' pollination biology. The wildflowerPhlox drummondiihas a floral syndrome consistent with pollination by Lepidoptera. We tested this prediction using empirical data. MethodsWe observed each step of pollination inP. drummondii. First, we observed 55.5 h of floral visitation across the species range. We used temporal pollinator exclusion to determine the contribution of diurnal and nocturnal pollination to reproductive output. We then quantifiedP. drummondiipollen transfer by the dominant floral visitor,Battus philenor. Finally, we tested the effect ofB. philenorvisitation onP. drummondiireproduction by quantifying fruit set following single pollinator visits. ResultsBattus philenoris the primary pollinator ofP. drummondii. Pollination is largely diurnal, and we observed a variety of lepidopteran visitors during the diurnal period. However,B. philenorwas the most frequent visitor, representing 88.5% of all observed visits. Our results show thatB. philenoris an extremely common visitor and also an effective pollinator by demonstrating that individuals transfer pollen between flowers and that a single visit can elicit fruit set. ConclusionsOur data are consistent with the prediction of lepidopteran pollination and further reveal a single butterfly species,B. philenor, as the primary pollinator. Our study demonstrates the importance of empirical pollinator observations, adds to our understanding of pollination mechanics, and offers a specific case study of butterfly pollination.
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- Award ID(s):
- 1844906
- PAR ID:
- 10559888
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- American Journal of Botany
- Volume:
- 110
- Issue:
- 5
- ISSN:
- 0002-9122
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/ajb2.16172
