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Facilitative pollinator sharing decreases with floral similarity in multiple systems. Oecologia 2020; 195:273-286. [PMID: 33040162 DOI: 10.1007/s00442-020-04770-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Accepted: 09/25/2020] [Indexed: 01/25/2023]
Abstract
Investigating the factors that determine whether interactions are competitive or facilitative is essential to understanding community structure and trait evolution. Co-flowering plants interact indirectly through shared pollinators, and meta-analyses suggest that phylogenetic relatedness and floral trait similarity may predict the outcome of these interactions. In a comparative approach, we manipulated the floral community across five focal species to assess how floral similarity and phylogenetic relatedness affect the outcome of interactions. To assess the extent of pollinator-mediated competition versus facilitation, we compared pollen limitation in five focal species growing with floral neighbors (either congeners or neighbors from a different family) relative to a control (growing alone). We measured floral morphology, color, and nectar traits to calculate multivariate floral similarity between species pairs and inferred a phylogeny to calculate phylogenetic distance. Pollinator-mediated interaction values were regressed against floral similarity and phylogenetic distance. We found evidence of pollinator-mediated facilitation in nine of 13 species pairs. Furthermore, floral similarity and phylogenetic distance reduced facilitative interactions, but the latter relationship was not significant when controlling for the identity of the focal species. Our results suggest that facilitative pollinator sharing is more common than reported in the literature, but co-flowering plant species with similar floral traits are less likely to facilitate pollination. A better understanding of the factors that promote facilitation versus competition has important potential applications for managing rare and invasive species.
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2
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Vamosi JC, Gong YB, Adamowicz SJ, Packer L. Forecasting pollination declines through DNA barcoding: the potential contributions of macroecological and macroevolutionary scales of inquiry. THE NEW PHYTOLOGIST 2017; 214:11-18. [PMID: 27901268 DOI: 10.1111/nph.14356] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
While pollinators are widely acknowledged as important contributors to seed production in plant communities, we do not yet have a good understanding of the importance of pollinator specialists for this ecosystem service. Determination of the prevalence of pollinator specialists is often hindered by the occurrence of cryptic species and the limitations of observational data on pollinator visitation rates, two areas where DNA barcoding of pollinators and pollen can be useful. Further, the demonstrated adequacy of pollen DNA barcoding from historical records offers opportunities to observe the effects of pollinator loss over longer timescales, and phylogenetic approaches can elucidate the historical rates of extinction of specialist lineages. In this Viewpoint article, we review how advances in DNA barcoding and metabarcoding of plants and pollinators have brought important developments to our understanding of specialization in plant-pollinator interactions. We then put forth several lines of inquiry that we feel are especially promising for providing insight on changes in plant-pollinator interactions over space and time. Obtaining estimates of the effects of reductions in specialists will contribute to forecasting the loss of ecosystem services that will accompany the erosion of plant and pollinator diversity.
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Affiliation(s)
- Jana C Vamosi
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada
| | - Yan-Bing Gong
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Sarah J Adamowicz
- Biodiversity Institute of Ontario & Department of Integrative Biology, University of Guelph, 50 Stone Road East, Guelph, ON, N1G 2W1, Canada
| | - Laurence Packer
- Department of Biology, York University, Toronto, ON, M3J 1P3, Canada
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3
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Temporally dependent pollinator competition and facilitation with mass flowering crops affects yield in co-blooming crops. Sci Rep 2017; 7:45296. [PMID: 28345653 PMCID: PMC5366890 DOI: 10.1038/srep45296] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 02/23/2017] [Indexed: 11/23/2022] Open
Abstract
One of the greatest challenges in sustainable agricultural production is managing ecosystem services, such as pollination, in ways that maximize crop yields. Most efforts to increase services by wild pollinators focus on management of natural habitats surrounding farms or non-crop habitats within farms. However, mass flowering crops create resource pulses that may be important determinants of pollinator dynamics. Mass bloom attracts pollinators and it is unclear how this affects the pollination and yields of other co-blooming crops. We investigated the effects of mass flowering apple on the pollinator community and yield of co-blooming strawberry on farms spanning a gradient in cover of apple orchards in the landscape. The effect of mass flowering apple on strawberry was dependent on the stage of apple bloom. During early and peak apple bloom, pollinator abundance and yield were reduced in landscapes with high cover of apple orchards. Following peak apple bloom, pollinator abundance was greater on farms with high apple cover and corresponded with increased yields on these farms. Spatial and temporal overlap between mass flowering and co-blooming crops alters the strength and direction of these dynamics and suggests that yields can be optimized by designing agricultural systems that avoid competition while maximizing facilitation.
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Arceo-Gómez G, Alonso C, Abdala-Roberts L, Parra-Tabla V. Patterns and sources of variation in pollen deposition and pollen tube formation in flowers of the endemic monoecious shrub Cnidoscolus souzae (Euphorbiaceae). PLANT BIOLOGY (STUTTGART, GERMANY) 2016; 18:594-600. [PMID: 26916543 DOI: 10.1111/plb.12445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 02/19/2016] [Indexed: 06/05/2023]
Abstract
Pollen deposition and pollen tube formation are key components of angiosperm reproduction but intraspecific variation in these has rarely been quantified. Documenting and partitioning (populations, plants and flowers) natural variation in these two aspects of plant reproduction can help uncover spatial mosaics of reproductive success and underlying causes. In this study, we assess variation in pollen deposition and pollen tube formation for the endemic monoecious shrub Cnidoscolus souzae throughout its distribution range in Mexico, and determine how this variation is structured among populations, plants and flowers. We also infer the relative importance of pollen quantity and quality in determining pollination success in this species. While we found no evidence suggesting that pollen receipt limits C. souzae reproduction across 19 populations, we did find extensive variation in pollen load size and pollen tube number per flower. Total variation in pollen receipt and pollen tube number was mostly explained by intra-individual and among-population variance. Furthermore, pollen load size had a stronger effect on the number of pollen tubes at the base of the style than pollen germination rate, suggesting that pollen quantity may be more important than quality for pollen tube success in C. souzae. Our results suggest that both small within-plant flower differences and broad-scale differences in community attributes can play an important role in determining pollination success. We emphasise the need to evaluate patterns and sources of variation in pollen deposition and pollen tube formation as a first step in understanding the causes of variation in pollination success over broad spatial scales.
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Affiliation(s)
- G Arceo-Gómez
- Department of Tropical Ecology, University of Yucatan, Merida-Xtmakuil, Yucatan, Mexico
| | - C Alonso
- Department of Evolutionary Ecology, Estación Biológica de Doñana, CSIC, Sevilla, Spain
| | - L Abdala-Roberts
- Department of Tropical Ecology, University of Yucatan, Merida-Xtmakuil, Yucatan, Mexico
| | - V Parra-Tabla
- Department of Tropical Ecology, University of Yucatan, Merida-Xtmakuil, Yucatan, Mexico
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5
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MacIvor JS, Cadotte MW, Livingstone SW, Lundholm JT, Yasui SLE. Phylogenetic ecology and the greening of cities. J Appl Ecol 2016. [DOI: 10.1111/1365-2664.12667] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- James S. MacIvor
- Department of Biological Sciences; University of Toronto Scarborough; 1265 Military Trail Toronto ON Canada
| | - Marc W. Cadotte
- Department of Biological Sciences; University of Toronto Scarborough; 1265 Military Trail Toronto ON Canada
- Stake Key Laboratory of Biocontrol; Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong; Higher Education Institutes; College of Ecology and Evolution; Sun Yat-sen University; Guangzhou PR China
- Department of Ecology and Evolutionary Biology; University of Toronto; 25 Willcocks St. Toronto ON Canada
| | - Stuart W. Livingstone
- Department of Physical & Environmental Sciences; University of Toronto Scarborough; 1265 Military Trail Toronto ON Canada
| | - Jeremy T. Lundholm
- Biology Department; Saint Mary's University; 923 Robie St. Halifax NS Canada
| | - Simone-Louise E. Yasui
- Department of Ecology and Evolutionary Biology; University of Toronto; 25 Willcocks St. Toronto ON Canada
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6
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Astegiano J, Massol F, Vidal MM, Cheptou PO, Guimarães PR. The robustness of plant-pollinator assemblages: linking plant interaction patterns and sensitivity to pollinator loss. PLoS One 2015; 10:e0117243. [PMID: 25646762 PMCID: PMC4315602 DOI: 10.1371/journal.pone.0117243] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 12/20/2014] [Indexed: 11/19/2022] Open
Abstract
Most flowering plants depend on pollinators to reproduce. Thus, evaluating the robustness of plant-pollinator assemblages to species loss is a major concern. How species interaction patterns are related to species sensitivity to partner loss may influence the robustness of plant-pollinator assemblages. In plants, both reproductive dependence on pollinators (breeding system) and dispersal ability may modulate plant sensitivity to pollinator loss. For instance, species with strong dependence (e.g. dioecious species) and low dispersal (e.g. seeds dispersed by gravity) may be the most sensitive to pollinator loss. We compared the interaction patterns of plants differing in dependence on pollinators and dispersal ability in a meta-dataset comprising 192 plant species from 13 plant-pollinator networks. In addition, network robustness was compared under different scenarios representing sequences of plant extinctions associated with plant sensitivity to pollinator loss. Species with different dependence on pollinators and dispersal ability showed similar levels of generalization. Although plants with low dispersal ability interacted with more generalized pollinators, low-dispersal plants with strong dependence on pollinators (i.e. the most sensitive to pollinator loss) interacted with more particular sets of pollinators (i.e. shared a low proportion of pollinators with other plants). Only two assemblages showed lower robustness under the scenario considering plant generalization, dependence on pollinators and dispersal ability than under the scenario where extinction sequences only depended on plant generalization (i.e. where higher generalization level was associated with lower probability of extinction). Overall, our results support the idea that species generalization and network topology may be good predictors of assemblage robustness to species loss, independently of plant dispersal ability and breeding system. In contrast, since ecological specialization among partners may increase the probability of disruption of interactions, the fact that the plants most sensitive to pollinator loss interacted with more particular pollinator assemblages suggest that the persistence of these plants and their pollinators might be highly compromised.
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Affiliation(s)
- Julia Astegiano
- CEFE UMR 5175, CNRS—Université de Montpellier—Université Paul-Valéry Montpellier—EPHE campus CNRS, Montpellier, France
- Departamento de Ecologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
- * E-mail:
| | - François Massol
- CEFE UMR 5175, CNRS—Université de Montpellier—Université Paul-Valéry Montpellier—EPHE campus CNRS, Montpellier, France
- Laboratoire GEPV, CNRS UMR 8198, Université Lille 1, Villeneuve d’Ascq, France
| | - Mariana Morais Vidal
- Departamento de Ecologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Pierre-Olivier Cheptou
- CEFE UMR 5175, CNRS—Université de Montpellier—Université Paul-Valéry Montpellier—EPHE campus CNRS, Montpellier, France
| | - Paulo R. Guimarães
- Departamento de Ecologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
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Arceo-Gómez G, Ashman TL. Patterns of pollen quantity and quality limitation of pre-zygotic reproduction inMimulus guttatusvary with co-flowering community context. OIKOS 2014. [DOI: 10.1111/oik.01309] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Gerardo Arceo-Gómez
- Dept of Biological Sciences; Univ. of Pittsburgh; 4249 Fifth Avenue Pittsburgh PA 15260-3929 USA
| | - Tia-Lynn Ashman
- Dept of Biological Sciences; Univ. of Pittsburgh; 4249 Fifth Avenue Pittsburgh PA 15260-3929 USA
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8
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Devaux C, Lepers C, Porcher E. Constraints imposed by pollinator behaviour on the ecology and evolution of plant mating systems. J Evol Biol 2014; 27:1413-30. [PMID: 24750302 DOI: 10.1111/jeb.12380] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 01/31/2014] [Accepted: 03/20/2014] [Indexed: 01/10/2023]
Abstract
Most flowering plants rely on pollinators for their reproduction. Plant-pollinator interactions, although mutualistic, involve an inherent conflict of interest between both partners and may constrain plant mating systems at multiple levels: the immediate ecological plant selfing rates, their distribution in and contribution to pollination networks, and their evolution. Here, we review experimental evidence that pollinator behaviour influences plant selfing rates in pairs of interacting species, and that plants can modify pollinator behaviour through plastic and evolutionary changes in floral traits. We also examine how theoretical studies include pollinators, implicitly or explicitly, to investigate the role of their foraging behaviour in plant mating system evolution. In doing so, we call for more evolutionary models combining ecological and genetic factors, and additional experimental data, particularly to describe pollinator foraging behaviour. Finally, we show that recent developments in ecological network theory help clarify the impact of community-level interactions on plant selfing rates and their evolution and suggest new research avenues to expand the study of mating systems of animal-pollinated plant species to the level of the plant-pollinator networks.
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Affiliation(s)
- C Devaux
- Institut des Sciences de l'Evolution de Montpellier, UMR 5554, Université Montpellier 2, Montpellier, France
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Arceo-Gómez G, Ashman TL. Coflowering Community Context Influences Female Fitness and Alters the Adaptive Value of Flower Longevity in Mimulus guttatus. Am Nat 2014; 183:E50-63. [DOI: 10.1086/674358] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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10
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Janovský Z, Mikát M, Hadrava J, Horčičková E, Kmecová K, Požárová D, Smyčka J, Herben T. Conspecific and heterospecific plant densities at small-scale can drive plant-pollinator interactions. PLoS One 2013; 8:e77361. [PMID: 24204818 PMCID: PMC3804547 DOI: 10.1371/journal.pone.0077361] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 09/02/2013] [Indexed: 11/25/2022] Open
Abstract
Generalist pollinators are important in many habitats, but little research has been done on small-scale spatial variation in interactions between them and the plants that they visit. Here, using a spatially explicit approach, we examined whether multiple species of flowering plants occurring within a single meadow showed spatial structure in their generalist pollinator assemblages. We report the results for eight plant species for which at least 200 individual visits were recorded. We found that for all of these species, the proportions of their general pollinator assemblages accounted for by particular functional groups showed spatial heterogeneity at the scale of tens of metres. This heterogeneity was connected either with no or only subtle changes of vegetation and flowering species composition. In five of these species, differences in conspecific plant density influenced the pollinator communities (with greater dominance of main pollinators at low-conspecific plant densities). The density of heterospecific plant individuals influenced the pollinator spectrum in one case. Our results indicate that the picture of plant-pollinator interactions provided by averaging data within large plots may be misleading and that within-site spatial heterogeneity should be accounted for in terms of sampling effort allocation and analysis. Moreover, spatially structured plant-pollinator interactions may have important ecological and evolutionary consequences, especially for plant population biology.
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Affiliation(s)
- Zdeněk Janovský
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
| | - Michael Mikát
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
| | - Jiří Hadrava
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
| | - Eva Horčičková
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
| | | | | | - Jan Smyčka
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
| | - Tomáš Herben
- Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic
- Institute of Botany, Academy of Sciences of the Czech Republic, Průhonice by Prague, Czech Republic
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11
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Ashman TL, Arceo-Gómez G. Toward a predictive understanding of the fitness costs of heterospecific pollen receipt and its importance in co-flowering communities. AMERICAN JOURNAL OF BOTANY 2013; 100:1061-70. [PMID: 23624924 DOI: 10.3732/ajb.1200496] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
PREMISE OF THE STUDY While we have a good understanding of how co-flowering plants interact via pollinator foraging, we still know very little about how plants interact via heterospecific pollen (HP) receipt. To fill this gap, we sought to illuminate the extent of HP receipt and quantitatively evaluate the fitness consequences of HP receipt. We consider plant traits that could mediate the fitness costs of HP receipt in an effort to better understand the potential consequences of pollinator sharing in natural communities. • METHODS We survey the literature for occurrence of HP receipt and assess variation in the fitness effects of a standard HP treatment. We develop a conceptual framework for understanding variation in fitness consequences of HP receipt. • KEY RESULTS We find evidence for variation in HP receipt and its costs. Our framework predicts that certain traits (self-incompatibility, small, highly aperaturate or allelopathic pollen) will lead to detrimental HP donors, whereas others (self-compatibility, small or wet stigmas, short styles) will lead to vulnerable HP recipients. We also predict that detrimental effects of HP receipt will increase with decreasing phylogenetic distance between donor and recipient. • CONCLUSIONS Our framework can guide much needed additional work so that we can evaluate whether and which plant traits contribute to the variation in the effects of HP receipt. This will be a step toward predicting the consequences of HP receipt in natural communities, and ultimately transform our understanding of the role of postpollination interactions in floral trait evolution and pollinator sharing.
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Affiliation(s)
- Tia-Lynn Ashman
- Department of Biological Sciences, University of Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA 15260-3929, USA.
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12
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Srivastava DS, Cadotte MW, MacDonald AAM, Marushia RG, Mirotchnick N. Phylogenetic diversity and the functioning of ecosystems. Ecol Lett 2012; 15:637-48. [PMID: 22583836 DOI: 10.1111/j.1461-0248.2012.01795.x] [Citation(s) in RCA: 269] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 01/14/2012] [Accepted: 03/29/2012] [Indexed: 11/30/2022]
Abstract
Phylogenetic diversity (PD) describes the total amount of phylogenetic distance among species in a community. Although there has been substantial research on the factors that determine community PD, exploration of the consequences of PD for ecosystem functioning is just beginning. We argue that PD may be useful in predicting ecosystem functions in a range of communities, from single-trophic to complex networks. Many traits show a phylogenetic signal, suggesting that PD can estimate the functional trait space of a community, and thus ecosystem functioning. Phylogeny also determines interactions among species, and so could help predict how extinctions cascade through ecological networks and thus impact ecosystem functions. Although the initial evidence available suggests patterns consistent with these predictions, we caution that the utility of PD depends critically on the strength of phylogenetic signals to both traits and interactions. We advocate for a synthetic approach that incorporates a deeper understanding of how traits and interactions are shaped by evolution, and outline key areas for future research. If these complexities can be incorporated into future studies, relationships between PD and ecosystem function bear promise in conceptually unifying evolutionary biology with ecosystem ecology.
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Affiliation(s)
- Diane S Srivastava
- Department of Zoology & Biodiversity Research Centre, University of British Columbia, 6270 University Blvd, Vancouver, British Columbia, V6T 1Z4, Canada.
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Arceo-Gómez G, Ashman TL. Heterospecific pollen deposition: does diversity alter the consequences? THE NEW PHYTOLOGIST 2011; 192:738-746. [PMID: 21777248 DOI: 10.1111/j.1469-8137.2011.03831.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
• In natural communities, plants can receive pollen from multiple heterospecifics as well as conspecifics. However, studies on the effects of interspecific pollen transfer have focused on interactions between species pairs. The potential exists for diverse interactions among heterospecific pollen (HP) grains on the stigma, and for these to affect plant reproduction, alone or in combination with conspecific pollen (CP) loss, but these interactions have not yet been explored. • We used hand-pollinations to simulate increasing community diversity and CP loss on Mimulus guttatus stigmas. We used pollen mixes of one to three heterospecific donors to determine how species composition and CP load size affect seed production and to characterize the mechanisms underlying fertilization failure. • Heterospecific pollen deposition reduced M. guttatus seed production and while the effect increased with the number of heterospecific donors, the strength depended on species composition and was independent of conspecific load size. Different types of interactions (additive and synergistic) are hypothesized to underlie the diverse effects on M. guttatus reproductive success. • Our results suggest that an increase in the diversity of heterospecific donors will not always lead to a greater decrease in fitness because multispecies effects depend on the interacting species.
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Affiliation(s)
- Gerardo Arceo-Gómez
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
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14
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Sargent RD, Kembel SW, Emery NC, Forrestel EJ, Ackerly DD. Effect of local community phylogenetic structure on pollen limitation in an obligately insect-pollinated plant. AMERICAN JOURNAL OF BOTANY 2011; 98:283-289. [PMID: 21613117 DOI: 10.3732/ajb.1000329] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
PREMISE OF THE STUDY Pollination is a key aspect of ecosystem function in the majority of land plant communities. It is well established that many animal-pollinated plants suffer lower seed set than they are capable of, likely because of competition for pollinators. Previously, competition for pollinator services has been shown to be most intense in communities with the greatest plant diversity. In spite of the fact that community evolutionary relations have a demonstrated impact on many ecological processes, their role in competition for pollinator services has rarely been examined. METHODS In this study, we explore relations among several aspects of the surrounding plant community, including species richness, phylodiversity, evolutionary distance from a focal species, and pollen limitation in an annual insect-pollinated plant. KEY RESULTS We did not find a significant effect of species richness on competition for pollination. However, consistent with a greater role for facilitation than competition, we found that a focal species occurring in communities composed of species of close relatives, especially other members of the Asteraceae, was less pollen limited than when it occurred in communities composed of more distant relatives. CONCLUSIONS Our results demonstrate that community phylodiversity is an important correlate of pollen limitation in this system and that it has greater explanatory power than species richness alone.
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Affiliation(s)
- Risa D Sargent
- Department of Integrative Biology, University of California, Berkeley, CA, USA.
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