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Iriart V, Baucom RS, Ashman TL. Interspecific variation in resistance and tolerance to herbicide drift reveals potential consequences for plant community co-flowering interactions and structure at the agro-eco interface. ANNALS OF BOTANY 2022; 130:1015-1028. [PMID: 36415945 PMCID: PMC9851304 DOI: 10.1093/aob/mcac137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/02/2022] [Accepted: 11/08/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND AND AIMS When plant communities are exposed to herbicide 'drift', wherein particles containing the active ingredient travel off-target, interspecific variation in resistance or tolerance may scale up to affect community dynamics. In turn, these alterations could threaten the diversity and stability of agro-ecosystems. We investigated the effects of herbicide drift on the growth and reproduction of 25 wild plant species to make predictions about the consequences of drift exposure on plant-plant interactions and the broader ecological community. METHODS We exposed potted plants from species that commonly occur in agricultural areas to a drift-level dose of the widely used herbicide dicamba or a control solution in the glasshouse. We evaluated species-level variation in resistance and tolerance for vegetative and floral traits. We assessed community-level impacts of drift by comparing the species evenness and flowering networks of glasshouse synthetic communities comprised of drift-exposed and control plants. KEY RESULTS Species varied significantly in resistance and tolerance to dicamba drift: some were negatively impacted while others showed overcompensatory responses. Species also differed in the way they deployed flowers over time following drift exposure. While drift had negligible effects on community evenness based on vegetative biomass, it caused salient differences in the structure of co-flowering networks within communities. Drift reduced the degree and intensity of flowering overlap among species, altered the composition of groups of species that were more likely to co-flower with each other than with others and shifted species roles (e.g. from dominant to inferior floral producers, and vice versa). CONCLUSIONS These results demonstrate that even low levels of herbicide exposure can significantly alter plant growth and reproduction, particularly flowering phenology. If field-grown plants respond similarly, then these changes would probably impact plant-plant competitive dynamics and potentially plant-pollinator interactions occurring within plant communities at the agro-ecological interface.
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Affiliation(s)
- Veronica Iriart
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Regina S Baucom
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Tia-Lynn Ashman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
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2
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Pollination success increases with plant diversity in high-Andean communities. Sci Rep 2021; 11:22107. [PMID: 34764375 PMCID: PMC8586006 DOI: 10.1038/s41598-021-01611-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 10/27/2021] [Indexed: 11/25/2022] Open
Abstract
Pollinator-mediated plant–plant interactions have traditionally been viewed within the competition paradigm. However, facilitation via pollinator sharing might be the rule rather than the exception in harsh environments. Moreover, plant diversity could be playing a key role in fostering pollinator-mediated facilitation. Yet, the facilitative effect of plant diversity on pollination remains poorly understood, especially under natural conditions. By examining a total of 9371 stigmas of 88 species from nine high-Andean communities in NW Patagonia, we explored the prevalent sign of the relation between conspecific pollen receipt and heterospecific pollen diversity, and assessed whether the incidence of different outcomes varies with altitude and whether pollen receipt relates to plant diversity. Conspecific pollen receipt increased with heterospecific pollen diversity on stigmas. In all communities, species showed either positive or neutral but never negative relations between the number of heterospecific pollen donor species and conspecific pollen receipt. The incidence of species showing positive relations increased with altitude. Finally, stigmas collected from communities with more co-flowering species had richer heterospecific pollen loads and higher abundance of conspecific pollen grains. Our findings suggest that plant diversity enhances pollination success in high-Andean plant communities. This study emphasizes the importance of plant diversity in fostering indirect plant–plant facilitative interactions in alpine environments, which could promote species coexistence and biodiversity maintenance.
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Smith GX, Swartz MT, Spigler RB. Causes and consequences of variation in heterospecific pollen receipt in Oenothera fruticosa. AMERICAN JOURNAL OF BOTANY 2021; 108:1612-1624. [PMID: 34460097 PMCID: PMC9291898 DOI: 10.1002/ajb2.1720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 05/25/2021] [Indexed: 05/05/2023]
Abstract
PREMISE Heterospecific pollen transfer, the transfer of pollen between species, is common among co-flowering plants, yet the amount of pollen received is extremely variable among species. Intraspecific variation in heterospecific pollen receipt can be even greater, but we lack an understanding of its causes and fitness consequences in wild populations. METHODS We examined potential drivers of variation in heterospecific pollen receipt in Oenothera fruticosa. We evaluated the relationship between heterospecific and conspecific pollen receipt and considered how visitation by different pollinator groups, local floral neighborhood composition, and flowering phenology affect the total amount and proportion of heterospecific pollen received. Finally, we tested whether variation in heterospecific pollen receipt translated into lower seed production. RESULTS Heterospecific pollen was ubiquitous on O. fruticosa stigmas, but the amount received was highly variable and unrelated to conspecific pollen receipt. Heterospecific pollen receipt depended on pollinator type, the proportion of nearby conspecific flowers, and flowering date. Significant interactions revealed that the effects of pollinator type and neighborhood were not independent, further contributing to variation in heterospecific pollen. Naturally occurring levels of heterospecific pollen were sufficient to negatively impact seed set, but large amounts of conspecific pollen counteracted this detrimental effect. CONCLUSIONS Although selection could act on floral traits that attract quality pollinators and promote synchronous flowering in O. fruticosa, the risk of heterospecific pollen is equally dependent on local floral context. This work highlights how extrinsic and intrinsic factors contribute to intraspecific variation in heterospecific pollen receipt in wild plants, with significant fitness consequences.
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Affiliation(s)
- Gerard X. Smith
- Department of BiologyTemple University1900 N. 12 StreetPhiladelphiaPA19122USA
| | - Mark T. Swartz
- The Pennsylvania Department of Military and Veterans AffairsFort Indiantown Gap National Guard Training CenterAnnvillePA17003USA
| | - Rachel B. Spigler
- Department of BiologyTemple University1900 N. 12 StreetPhiladelphiaPA19122USA
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4
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Smith GX, Swartz MT, Spigler RB. Causes and consequences of variation in heterospecific pollen receipt in Oenothera fruticosa. AMERICAN JOURNAL OF BOTANY 2021; 108:1612-1624. [PMID: 34460097 DOI: 10.5061/dryad.hqbzkh1g9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 05/25/2021] [Indexed: 05/22/2023]
Abstract
PREMISE Heterospecific pollen transfer, the transfer of pollen between species, is common among co-flowering plants, yet the amount of pollen received is extremely variable among species. Intraspecific variation in heterospecific pollen receipt can be even greater, but we lack an understanding of its causes and fitness consequences in wild populations. METHODS We examined potential drivers of variation in heterospecific pollen receipt in Oenothera fruticosa. We evaluated the relationship between heterospecific and conspecific pollen receipt and considered how visitation by different pollinator groups, local floral neighborhood composition, and flowering phenology affect the total amount and proportion of heterospecific pollen received. Finally, we tested whether variation in heterospecific pollen receipt translated into lower seed production. RESULTS Heterospecific pollen was ubiquitous on O. fruticosa stigmas, but the amount received was highly variable and unrelated to conspecific pollen receipt. Heterospecific pollen receipt depended on pollinator type, the proportion of nearby conspecific flowers, and flowering date. Significant interactions revealed that the effects of pollinator type and neighborhood were not independent, further contributing to variation in heterospecific pollen. Naturally occurring levels of heterospecific pollen were sufficient to negatively impact seed set, but large amounts of conspecific pollen counteracted this detrimental effect. CONCLUSIONS Although selection could act on floral traits that attract quality pollinators and promote synchronous flowering in O. fruticosa, the risk of heterospecific pollen is equally dependent on local floral context. This work highlights how extrinsic and intrinsic factors contribute to intraspecific variation in heterospecific pollen receipt in wild plants, with significant fitness consequences.
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Affiliation(s)
- Gerard X Smith
- Department of Biology, Temple University, 1900 N. 12th Street, Philadelphia, PA, 19122, USA
| | - Mark T Swartz
- The Pennsylvania Department of Military and Veterans Affairs, Fort Indiantown Gap National Guard Training Center, Annville, PA, 17003, USA
| | - Rachel B Spigler
- Department of Biology, Temple University, 1900 N. 12th Street, Philadelphia, PA, 19122, USA
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5
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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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Shrestha M, Dyer AG, Garcia JE, Burd M. Floral colour structure in two Australian herbaceous communities: it depends on who is looking. ANNALS OF BOTANY 2019; 124:221-232. [PMID: 31008511 PMCID: PMC6758583 DOI: 10.1093/aob/mcz043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 03/14/2019] [Indexed: 05/03/2023]
Abstract
BACKGROUND AND AIMS Pollinator-mediated interactions between plant species may affect the composition of angiosperm communities. Floral colour signals should play a role in these interactions, but the role will arise from the visual perceptions and behavioural responses of multiple pollinators. Recent advances in the visual sciences can be used to inform our understanding of these perceptions and responses. We outline the application of appropriate visual principles to the analysis of the annual cycle of floral colour structure in two Australian herbaceous communities. METHODS We used spectrographic measurements of petal reflectance to determine the location of flowers in a model of hymenopteran colour vision. These representations of colour perception were then translated to a behaviourally relevant metric of colour differences using empirically calibrated colour discrimination functions for four hymenopteran species. We then analysed the pattern of colour similarity in terms of this metric in samples of co-flowering plants over the course of a year. We used the same method to analyse the annual pattern of phylogenetic relatedness of co-flowering plants in order to compare colour structure and phylogenetic structure. KEY RESULTS Co-flowering communities at any given date seldom had colour assemblages significantly different from random. Non-random structure, both dispersion and clustering, occurred occasionally, but depended on which bee observer is considered. The degree of colour similarity was unrelated to phylogenetic similarity within a co-flowering community. CONCLUSIONS Perceived floral colour structure varied with the sensory capabilities of the observer. The lack of colour structure at most sample dates, particularly the rarity of strong dispersion, suggests that plants do not use chromatic signals primarily to enable bees to discriminate between co-flowering species. It is more likely that colours make plants detectable in a complex landscape.
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Affiliation(s)
- Mani Shrestha
- School of Biological Sciences, Monash University, Melbourne, Australia
- School of Media and Communication, RMIT University, Melbourne, Australia
| | - Adrian G Dyer
- School of Media and Communication, RMIT University, Melbourne, Australia
- Department of Physiology, Monash University, Melbourne, Australia
- For correspondence. E-mail
| | - Jair E Garcia
- School of Media and Communication, RMIT University, Melbourne, Australia
| | - Martin Burd
- School of Biological Sciences, Monash University, Melbourne, Australia
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7
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Are there magnet plants in Australian ecosystems: Pollinator visits to neighbouring plants are not affected by proximity to mass flowering plants. Basic Appl Ecol 2019. [DOI: 10.1016/j.baae.2018.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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8
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Simmons BI, Cirtwill AR, Baker NJ, Wauchope HS, Dicks LV, Stouffer DB, Sutherland WJ. Motifs in bipartite ecological networks: uncovering indirect interactions. OIKOS 2018. [DOI: 10.1111/oik.05670] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Benno I. Simmons
- Dept of Zoology, Univ. of Cambridge, The David Attenborough Building, Pembroke Street; Cambridge CB2 3QZ UK
| | - Alyssa R. Cirtwill
- Dept of Physics, Chemistry and Biology (IFM), Linköping Univ; Linköping Sweden
| | - Nick J. Baker
- Centre for Integrative Ecology, School of Biological Sciences, Univ. of Canterbury; Christchurch New Zealand
| | - Hannah S. Wauchope
- Dept of Zoology, Univ. of Cambridge, The David Attenborough Building, Pembroke Street; Cambridge CB2 3QZ UK
| | - Lynn V. Dicks
- School of Biological Sciences, Univ. of East Anglia; UK
| | - Daniel B. Stouffer
- Centre for Integrative Ecology, School of Biological Sciences, Univ. of Canterbury; Christchurch New Zealand
| | - William J. Sutherland
- Dept of Zoology, Univ. of Cambridge, The David Attenborough Building, Pembroke Street; Cambridge CB2 3QZ UK
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9
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Pauw A, Johnson CM. Mutualism between co-occurring plant species in South Africa's Mediterranean climate heathland is mediated by birds. PLANT BIOLOGY (STUTTGART, GERMANY) 2018; 20 Suppl 1:224-230. [PMID: 28960844 DOI: 10.1111/plb.12635] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 09/21/2017] [Indexed: 06/07/2023]
Abstract
Interactions among plant species via pollinators vary from competitive to mutualistic and can influence the probability of stable coexistence of plant species. We aimed to determine the nature of the interaction via flower visitors between Leucospermum conocarpodendron and Mimetes fimbriifolius, two shrubs in the Proteaceae that share many ecological traits and coexist on the Cape Peninsula, South Africa. To assess the extent of pollinator sharing we analysed nectar properties and recorded the pollinator fauna, their behaviour and contribution to seed set. To test for competition via interspecific pollen transfer, we recorded the movement patterns of pollinators and quantified pollen loads. To determine the effect of co-flowering on visitation rates we recorded visits in stands that varied in the density of the two species. We found that the species produce similar rewards and share pollinating Cape Sugarbirds (Promerops cafer). Interspecific pollen transfer is avoided by placing pollen on different parts of the bird. Both species are visited by nectar-thieving Orange-breasted Sunbirds (Anthobaphes violacea). Insects and autonomous self-pollination contributed little to seed set. Pollinator visits increased with conspecific density in both species, and the slope of the increase was steepest in the presence of high densities of the co-occurring plant species. Nectar thief visits also increased with conspecific density in both species, but the slope declined with increasing density of the co-occurring species. Co-occurrence enhanced pollinator visits and alleviated nectar robbing in both plant species, consistent with mutualisms. Mutualism within a trophic level is unusual, but may help to explain the stable coexistence of ecologically similar species.
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Affiliation(s)
- A Pauw
- Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - C M Johnson
- Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
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10
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Charlebois JA, Sargent RD. No consistent pollinator-mediated impacts of alien plants on natives. Ecol Lett 2017; 20:1479-1490. [PMID: 28901037 DOI: 10.1111/ele.12831] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 06/08/2017] [Accepted: 07/31/2017] [Indexed: 11/28/2022]
Abstract
The introduction of an alien plant is widely assumed to have negative consequences for the pollinator-mediated fitness of nearby natives. Indeed, a number of studies, including a highly cited meta-analysis, have concluded that the trend for such interactions is competitive. Here we provide evidence that publication bias and study design have obscured our ability to assess the pollinator-mediated impacts of alien plants. In a meta-analysis of 76 studies, we demonstrate that alien/native status does not predict the outcome of pollinator-mediated interactions among plants. Moreover, we found no evidence that similarity in floral traits or phylogenetic distance between species pairs influences the outcome of pollinator-mediated interactions. Instead, we report that aspects of study design, such as distance between the control and nearest neighbour, and/or the arrangement of study plants better predict the impact of a neighbour than does alien/native status. Our study sheds new light on the role that publication bias and experimental design play in the evaluation of key patterns in ecology. We conclude that, due to the absence of clear, generalisable pollinator-mediated impacts of alien species, management schemes should base decisions on community-wide assessments of the impacts of individual alien plant species, and not solely on alien/native status itself.
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Affiliation(s)
| | - Risa D Sargent
- Department of Biology, University of Ottawa, Ottawa, ON, Canada
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11
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Tóth P, Undas AK, Verstappen F, Bouwmeester H. Floral Volatiles in Parasitic Plants of the Orobanchaceae. Ecological and Taxonomic Implications. FRONTIERS IN PLANT SCIENCE 2016; 7:312. [PMID: 27014329 PMCID: PMC4791402 DOI: 10.3389/fpls.2016.00312] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Accepted: 02/29/2016] [Indexed: 05/11/2023]
Abstract
The holoparasitic broomrapes, Orobanche spp. and Phelipanche spp. (Orobanchaceae), are root parasites that completely depend on a host plant for survival and reproduction. There is considerable controversy on the taxonomy of this biologically and agronomically important family. Flowers of over 25 parasitic Orobanchaceae and a number of close, parasitic and non-parasitic, relatives emitted a complex blend of volatile organic compounds (VOCs), consisting of over 130 VOCs per species. Floral VOC blend-based phylogeny supported the known taxonomy in internal taxonomic grouping of genus and eliminated the uncertainty in some taxonomical groups. Moreover, phylogenetic analysis suggested separation of the broomrapes into two main groups parasitizing annual and perennial hosts, and for the annual hosts, into weedy and non-weedy broomrapes. We conclude that floral VOCs are a significant tool in species identification and possibly even in defining new species and can help to improve controversial taxonomy in the Orobanchaceae.
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Affiliation(s)
- Peter Tóth
- Laboratory of Plant Physiology, Wageningen University and Research CentreWageningen, Netherlands
- Department of Plant Protection, Slovak University of Agriculture in NitraNitra, Slovakia
| | - Anna K. Undas
- Laboratory of Plant Physiology, Wageningen University and Research CentreWageningen, Netherlands
- RIKILT, Wageningen University and Research CentreWageningen, Netherlands
| | - Francel Verstappen
- Laboratory of Plant Physiology, Wageningen University and Research CentreWageningen, Netherlands
| | - Harro Bouwmeester
- Laboratory of Plant Physiology, Wageningen University and Research CentreWageningen, Netherlands
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12
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Tur C, Sáez A, Traveset A, Aizen MA. Evaluating the effects of pollinator-mediated interactions using pollen transfer networks: evidence of widespread facilitation in south Andean plant communities. Ecol Lett 2016; 19:576-86. [DOI: 10.1111/ele.12594] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 11/06/2015] [Accepted: 02/04/2016] [Indexed: 11/26/2022]
Affiliation(s)
- C. Tur
- Cristina Tur. IMEDEA- Institut Mediterrani d'Estudis Avançats (CSIC-UIB); Miquel Marqués 21 07190 Esporles Illes Balears Spain
| | - A. Sáez
- Agustín Sáez. Laboratorio ECOTONO; INIBIOMA; UNComa. Pasaje Gutiérrez 1125 Bariloche Río Negro Argentina
| | - A. Traveset
- Anna Traveset. IMEDEA- Institut Mediterrani d'Estudis Avançats (CSIC-UIB); Miquel Marqués 21 07190 Esporles Illes Balears Spain
| | - M. A. Aizen
- Marcelo A. Aizen. Laboratorio ECOTONO; INIBIOMA; UNComa. Pasaje Gutiérrez 1125 Bariloche Río Negro Argentina
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13
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Liu YN, Li Y, Yang FS, Wang XQ. Floral nectary, nectar production dynamics, and floral reproductive isolation among closely related species of Pedicularis. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2016; 58:178-87. [PMID: 26172034 DOI: 10.1111/jipb.12374] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 07/06/2015] [Indexed: 05/22/2023]
Abstract
Floral nectar is thought to be one of the most important rewards that attract pollinators in Pedicularis; however, few studies have examined variation of nectary structure and/or nectar secretion in the genus, particularly among closely related species. Here we investigated nectary morphology, nectar quality, and nectar production dynamics in flowers of Pedicularis section Cyathophora. We found a conical floral nectary at the base of the ovary in species of the rex-thamnophila clade. Stomata were found on the surface of the nectary, and copious starch grains were detected in the nectary tissues. In contrast, a semi-annular nectary was found in flowers of the species of the superba clade. Only a few starch grains were observed in tissues of the semi-annular nectary, and the nectar sugar concentration in these flowers was much lower than that in the flowers of the rex-thamnophila clade. Our results indicate that the floral nectary has experienced considerable morphological, structural, and functional differentiation among closely related species of Pedicularis. This could have affected nectar production, leading to a shift of the pollination mode. Our results also imply that variation of the nectary morphology and nectar production may have played an important role in the speciation of sect. Cyathophora.
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Affiliation(s)
- Ya-Nan Liu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
- University of Chinese Academy of Sciences, Beijing, 100039, China
| | - Yan Li
- Institute of Alpine Economic Plant, Yunnan Academy of Agricultural Sciences, Lijiang, 674100, China
| | - Fu-Sheng Yang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
| | - Xiao-Quan Wang
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China
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14
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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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15
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Falik O, Hoffmann I, Novoplansky A. Say it with flowers: flowering acceleration by root communication. PLANT SIGNALING & BEHAVIOR 2014; 9:e28258. [PMID: 24598343 PMCID: PMC4091325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 02/17/2014] [Indexed: 03/29/2024]
Abstract
The timing of reproduction is a critical determinant of fitness, especially in organisms inhabiting seasonal environments. Increasing evidence suggests that inter-plant communication plays important roles in plant functioning. Here, we tested the hypothesis that flowering coordination can involve communication between neighboring plants. We show that soil leachates from Brassica rapa plants growing under long-day conditions accelerated flowering and decreased allocation to vegetative organs in target plants growing under non-inductive short-day conditions. The results suggest that besides endogenous signaling and external abiotic cues, flowering timing may involve inter-plant communication, mediated by root exudates. The study of flowering communication is expected to illuminate neglected aspects of plant reproductive interactions and to provide novel opportunities for controlling the timing of plant reproduction in agricultural settings.
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Affiliation(s)
- Omer Falik
- Mitrani Department of Desert Ecology; Blaustein Institutes for Desert Research; Ben-Gurion University of the Negev; Midreshet Ben-Gurion, 84990, Israel
| | - Ishay Hoffmann
- Mitrani Department of Desert Ecology; Blaustein Institutes for Desert Research; Ben-Gurion University of the Negev; Midreshet Ben-Gurion, 84990, Israel
| | - Ariel Novoplansky
- Mitrani Department of Desert Ecology; Blaustein Institutes for Desert Research; Ben-Gurion University of the Negev; Midreshet Ben-Gurion, 84990, Israel
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16
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Falik O, Hoffmann I, Novoplansky A. Say it with flowers: flowering acceleration by root communication. PLANT SIGNALING & BEHAVIOR 2014; 9:e28258. [PMID: 24598343 PMCID: PMC4091325 DOI: 10.4161/psb.28258] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 02/17/2014] [Indexed: 05/26/2023]
Abstract
The timing of reproduction is a critical determinant of fitness, especially in organisms inhabiting seasonal environments. Increasing evidence suggests that inter-plant communication plays important roles in plant functioning. Here, we tested the hypothesis that flowering coordination can involve communication between neighboring plants. We show that soil leachates from Brassica rapa plants growing under long-day conditions accelerated flowering and decreased allocation to vegetative organs in target plants growing under non-inductive short-day conditions. The results suggest that besides endogenous signaling and external abiotic cues, flowering timing may involve inter-plant communication, mediated by root exudates. The study of flowering communication is expected to illuminate neglected aspects of plant reproductive interactions and to provide novel opportunities for controlling the timing of plant reproduction in agricultural settings.
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Affiliation(s)
- Omer Falik
- Mitrani Department of Desert Ecology; Blaustein Institutes for Desert Research; Ben-Gurion University of the Negev; Midreshet Ben-Gurion, 84990, Israel
| | - Ishay Hoffmann
- Mitrani Department of Desert Ecology; Blaustein Institutes for Desert Research; Ben-Gurion University of the Negev; Midreshet Ben-Gurion, 84990, Israel
| | - Ariel Novoplansky
- Mitrani Department of Desert Ecology; Blaustein Institutes for Desert Research; Ben-Gurion University of the Negev; Midreshet Ben-Gurion, 84990, Israel
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17
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Yang CF, Wang QF, Guo YH. Pollination in a patchily distributed lousewort is facilitated by presence of a co-flowering plant due to enhancement of quantity and quality of pollinator visits. ANNALS OF BOTANY 2013; 112:1751-1758. [PMID: 24131615 PMCID: PMC3838553 DOI: 10.1093/aob/mct228] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 08/09/2013] [Indexed: 06/02/2023]
Abstract
BACKGROUND AND AIMS Plants surrounded by individuals of other co-flowering species may suffer a reproductive cost from interspecific pollen transfer (IPT). However, differences in floral architecture may reduce or eliminate IPT. METHODS A study was made of Pedicularis densispica (lousewort) and its common co-flowering species, Astragalus pastorius, to compare reproductive and pollination success of lousewort plants from pure and mixed patches. Floral architecture and pollinator behaviour on flowers of the two plants were compared along with the composition of stigmatic pollen load of the louseworts. The extent of pollen limitation of plants from pure and mixed patches was also explored through supplemental pollination with self- and outcross pollen (PLs and PLx). KEY RESULTS Mixed patches attracted many more nectar-searching individuals of Bombus richardsi. These bumble-bees moved frequently between flowers of the two species. However, they pollinated P. densispica with their dorsum and A. pastorius with their abdomen. This difference in handling almost completely eliminated IPT. Lousewort plants from mixed patches yielded more seeds, and seeds of higher mass and germinability, than those from pure patches. Moreover, louseworts from mixed patches had lower PLs and PLx compared with those from pure patches. CONCLUSIONS Differences in floral architecture induced differences in pollinator behaviour that minimized IPT, such that co-flowering plants significantly enhanced quantity and quality of pollinator visits for the lousewort plants in patchy habitat. These findings add to our understanding of the mechanisms of pollination facilitation.
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Affiliation(s)
- Chun-Feng Yang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, The Chinese Academy of Sciences, Wuhan 430074, China
| | - Qing-Feng Wang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, The Chinese Academy of Sciences, Wuhan 430074, China
| | - You-Hao Guo
- College of Life Sciences, Wuhan University, Wuhan 430072, China
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Natalis LC, Wesselingh RA. PARENTAL FREQUENCIES AND SPATIAL CONFIGURATION SHAPE BUMBLEBEE BEHAVIOR AND FLORAL ISOLATION IN HYBRIDIZINGRHINANTHUS. Evolution 2013; 67:1692-705. [DOI: 10.1111/evo.12044] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 11/14/2012] [Indexed: 11/28/2022]
Affiliation(s)
- Laurent C. Natalis
- Biodiversity Research Centre, Earth and Life Institute; Université catholique de Louvain; Croix du Sud 4-5 Box L7.07.04 B-1348 Louvain-la-Neuve Belgium
| | - Renate A. Wesselingh
- Biodiversity Research Centre, Earth and Life Institute; Université catholique de Louvain; Croix du Sud 4-5 Box L7.07.04 B-1348 Louvain-la-Neuve Belgium
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19
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Li AR, Smith FA, Smith SE, Guan KY. Two sympatric root hemiparasitic Pedicularis species differ in host dependency and selectivity under phosphorus limitation. FUNCTIONAL PLANT BIOLOGY : FPB 2012; 39:784-794. [PMID: 32480829 DOI: 10.1071/fp12159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Accepted: 07/19/2012] [Indexed: 05/12/2023]
Abstract
Parasitic biology of Pedicularis L. (Orobanchaceae) has been underinvestigated despite its wide distribution and potential ecological significance. To better understand the parasitic aspects of the root hemiparasites, host-parasite interactions were investigated with two sympatric Pedicularis species, Pedicularis rex C. B. Clarke and Pedicularis tricolor Hand.-Mazz., at two developmental stages. Plant DW, shoot phosphorus (P) content, root:shoot ratio and number of haustoria were measured in Pedicularis grown with either a host plant or a plant of its own species in pot experiments. In addition, effects of parasitism and intraspecific competition on growth and biomass allocation in four host species belonging to three major functional groups (grasses, legumes and forbs) were investigated. The two Pedicularis species showed obvious host preference, but preferred different host species. Interactions between Pedicularis and their hosts depended on both species identity and developmental stages of the partners. Overall, P. rex showed much weaker host dependency and less damage to hosts than P. tricolor. Interspecific variations were observed among different host species in their responses to intraspecific competition and parasitism. We concluded that different Pedicularis-host pairs showed different interaction patterns. Sympatric Pedicularis may have differential influence on plant community structure and productivity.
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Affiliation(s)
- Ai-Rong Li
- Key Laboratory of Economic Plants and Biotechnology, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming 650204, PR China
| | - F Andrew Smith
- Soils Group, School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, SA 5005, Australia
| | - Sally E Smith
- Soils Group, School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, SA 5005, Australia
| | - Kai-Yun Guan
- Key Laboratory of Economic Plants and Biotechnology, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming 650204, PR China
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