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Sorokhaibam SS, Chandra A, Baishya R, Barik SK, Goel S, Tandon R. Contradistinctive floral attributes, pollination guilds and their consequence on the outcrossing rate in two elevational morphs of Rhododendron arboreum Sm. FRONTIERS IN PLANT SCIENCE 2024; 15:1355680. [PMID: 38606073 PMCID: PMC11007036 DOI: 10.3389/fpls.2024.1355680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 03/18/2024] [Indexed: 04/13/2024]
Abstract
Infraspecific floral trait variations may appear in response to elevational differences in alpine plant species. There is enormous information on the selection of such morphs mediated by biotic and/or abiotic variables. Whether such differences contribute to differences in reproductive strategy and mating outcomes is rarely investigated. We investigated these aspects in two distinct elevational floral morphs (Red and Pink) of Rhododendron arboreum Sm. in Western Himalaya. The red morphs occupy the lower elevations while pink morphs the higher elevations. The two morphs differ in floral traits like phenology, dimension, display, quality of floral rewards, and pollinators that happen to influence interaction with available pollinator pool at each elevation. The pink morph exhibits entomophily, while the red ones show ornithophily. Although experimental pollinations established that both the morphs are self-compatible, selfing results in significantly lower fruit-set than either cross- or open-pollinations. The outcrossing rate in the red morph, as determined by using simple sequence repeat (SSR) markers, was higher (tm=0.82) than that in the pink morph (tm=0.76), with a tendency of the latter to be shifting towards mixed-mating strategy. However, the extent of biparental inbreeding was comparable among the two morphs. It is inferred that the differences in the mating outcomes among the morphs in the tree species are linked to those emerging from floral traits and the pollination by different functional groups of floral visitors.
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Affiliation(s)
| | - Atika Chandra
- Department of Botany, Maitreyi College, University of Delhi, New Delhi, India
| | - Ratul Baishya
- Department of Botany, University of Delhi, New Delhi, India
| | - Saroj Kanta Barik
- Department of Botany, Centre for Advanced Studies in Botany, North-Eastern Hill University, Shillong, India
| | | | - Rajesh Tandon
- Department of Botany, University of Delhi, New Delhi, India
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2
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Santos‐Gómez SM, Figueroa‐Castro DM, Castañeda‐Posadas C. Are floral traits good predictors of effective pollinators? A test of pollination syndromes. Ecol Res 2021. [DOI: 10.1111/1440-1703.12285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Samantha Maite Santos‐Gómez
- Facultad de Ciencias Biológicas Benemérita Universidad Autónoma de Puebla Puebla Mexico
- Maestría en Ciencias Biológicas, Facultad de Ciencias Biológicas Benemérita Universidad Autónoma de Puebla Puebla Mexico
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Hilpman ET, Busch JW. Floral traits differentiate pollination syndromes and species but fail to predict the identity of floral visitors to Castilleja. AMERICAN JOURNAL OF BOTANY 2021; 108:2150-2161. [PMID: 34716581 DOI: 10.1002/ajb2.1784] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 07/06/2021] [Accepted: 07/07/2021] [Indexed: 06/13/2023]
Abstract
PREMISE Animal pollination is critical to plant reproduction and may cause convergent evolution of pollination syndromes. Pollination syndromes in Castilleja have been distinguished based on floral traits and historical observations of floral visitors. Here we addressed these questions: (1) Can pollination syndromes be distinguished using floral morphological traits or volatile organic compound emissions? (2) Is there significant variation in floral traits within a pollination syndrome at the level of populations or species? (3) Do pollination syndromes predict the most frequent floral visitor to Castilleja? METHODS Floral traits and visitation were measured for five co-occurring Castilleja species (C. applegatei, C. linariifolia, C. miniata, C. nana, and C. peirsonii), representing three pollination syndromes (bee, fly, and hummingbird), at four sites in the Sierra Nevada Mountains. We used nonmetric multidimensional scaling (NMDS) and multiple linear regressions to address key questions in the differentiation of Castilleja and floral visitors. RESULTS Our analyses revealed that both morphological traits and floral VOCs can be used to distinguish between some pollination syndromes and Castilleja species. Morphological traits defined pollination syndromes reliably, but within the hummingbird syndrome, there was also significant variation among populations and species. Pollination syndrome was a poor predictor of visitors to Castilleja. CONCLUSIONS Floral trait differentiation among Castilleja individuals reflects both taxonomy and pollination syndromes. Differentiation was generally more evident in morphological traits compared to VOCs. Furthermore, a priori notions of pollination syndromes in this system are overly simplistic and fail to predict which animals most frequently visit Castilleja in natural populations.
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Affiliation(s)
- Evan T Hilpman
- Washington State University, School of Biological Sciences, Pullman, WA, 99164, USA
| | - Jeremiah W Busch
- Washington State University, School of Biological Sciences, Pullman, WA, 99164, USA
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Valverde‐Espinoza JM, Chacón‐Madrigal E, Alvarado‐Rodríguez O, Dellinger AS. The predictive power of pollination syndromes: Passerine pollination in heterantherous Meriania macrophylla (Benth.) Triana (Melastomataceae). Ecol Evol 2021; 11:13668-13677. [PMID: 34707808 PMCID: PMC8525179 DOI: 10.1002/ece3.8140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 08/18/2021] [Accepted: 08/23/2021] [Indexed: 11/19/2022] Open
Abstract
The cloud forest species Meriania macrophylla (Benth.) Triana has pseudocampanulate flowers with bulbous stamen appendages, typical for the passerine pollination syndrome found in the Melastomataceae tribe Merianieae. The species is further characterized by strong stamen dimorphism (heteranthery), a condition otherwise associated with pollen-rewarding bee-pollinated species (both in Melastomataceae and beyond). In passerine-pollinated Merianieae, however, flowers usually only show weak stamen dimorphism. Here, we conducted field and laboratory investigations to determine the pollinators of M. macrophylla and assess the potential role of strong heteranthery in this species. Our field observations in Costa Rica confirmed syndrome predictions and indeed proved pollination by passerine birds in M. macrophylla. The large bulbous set of stamens functions as a food-body reward to the pollinating birds, and as trigger for pollen release (bellows mechanism) as typical for the passerine syndrome in Merianieae. In contrast to other passerine-pollinated Merianieae, the second set of stamens has seemingly lost its rewarding and pollination function, however. Our results demonstrate the utility of the pollination syndrome concept even in light of potentially misleading traits such as strong heteranthery.
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Affiliation(s)
- José Miguel Valverde‐Espinoza
- Escuela de BiologíaUniversidad de Costa RicaSan JoséCosta Rica
- Department of Botany and Biodiversity ResearchUniversity of ViennaViennaAustria
| | - Eduardo Chacón‐Madrigal
- Escuela de BiologíaUniversidad de Costa RicaSan JoséCosta Rica
- Herbario Luis A. Fournier Origgi (USJ)Centro de Investigación en Biodiversidad y Ecología TropicalUniversidad de Costa RicaSan JoséCosta Rica
| | - Olman Alvarado‐Rodríguez
- Escuela de BiologíaUniversidad de Costa RicaSan JoséCosta Rica
- Centro de Investigación en Estructuras MicroscópicasUniversidad de Costa RicaSan JoséCosta Rica
| | - Agnes S. Dellinger
- Department of Botany and Biodiversity ResearchUniversity of ViennaViennaAustria
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5
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van der Niet T. Paucity of natural history data impedes phylogenetic analyses of pollinator-driven evolution. THE NEW PHYTOLOGIST 2021; 229:1201-1205. [PMID: 32786085 DOI: 10.1111/nph.16813] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 07/03/2020] [Indexed: 06/11/2023]
Affiliation(s)
- Timotheüs van der Niet
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, P. Bag X01, Pietermaritzburg, South Africa
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6
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Dellinger AS. Pollination syndromes in the 21 st century: where do we stand and where may we go? THE NEW PHYTOLOGIST 2020; 228:1193-1213. [PMID: 33460152 DOI: 10.1111/nph.16793] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 05/31/2020] [Indexed: 06/12/2023]
Abstract
Pollination syndromes, recurring suites of floral traits appearing in connection with specific functional pollinator groups, have served for decades to organise floral diversity under a functional-ecological perspective. Some potential caveats, such as over-simplification of complex plant-animal interactions or lack of empirical observations, have been identified and discussed in recent years. Which of these caveats do indeed cause problems, which have been solved and where do future possibilities lie? I address these questions in a review of the pollination-syndrome literature of 2010 to 2019. I show that the majority of studies was based on detailed empirical pollinator observations and could reliably predict pollinators based on a few floral traits such as colour, shape or reward. Some traits (i.e. colour) were less reliable in predicting pollinators than others (i.e. reward, corolla width), however. I stress that future studies should consider floral traits beyond those traditionally recorded to expand our understanding of mechanisms of floral evolution. I discuss statistical methods suitable for objectively analysing the interplay of system-specific evolutionary constraints, pollinator-mediated selection and adaptive trade-offs at microecological and macroecological scales. I exemplify my arguments on an empirical dataset of floral traits of a neotropical plant radiation in the family Melastomataceae.
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Wang X, Wen M, Qian X, Pei N, Zhang D. Plants are visited by more pollinator species than pollination syndromes predicted in an oceanic island community. Sci Rep 2020; 10:13918. [PMID: 32811900 PMCID: PMC7434763 DOI: 10.1038/s41598-020-70954-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 08/03/2020] [Indexed: 11/09/2022] Open
Abstract
The pollination syndrome concept has provided powerful utility in understanding the evolution and adaptation of floral traits. However, the utility of this conception has been questioned on the grounds that flowers usually attract a broader spectrum of visitors than one might expect. Furthermore, the relationship between plant specialization and floral traits is poorly understood. Here, we examined the applicability of using the pollination syndrome to predict the pollinators of plants on Yongxing Island. We used the species-level specialization of pollination networks to compare the difference of plant ecological specialization among floral traits. The result of full model was not significant, indicating that floral traits did not affect the pollinator functional groups. The five floral traits explained only 22.5% of the pollinator's visitation preference. Our results showed that plants were visited by more pollinator species than pollination syndromes predicted. Plants with restrictive flowers showed higher specialization than those with unrestrictive flowers, while other floral traits exhibited no significant effect on plant specialization. Generalized pollination system on oceanic island might influence the predictive accuracy of pollination syndromes and the relationship between floral traits and plant ecological specialization. Our findings highlighted the utility and limitations of pollination syndromes concept in oceanic island communities.
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Affiliation(s)
- Xiangping Wang
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, Guangdong, China
| | - Meihong Wen
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, Guangdong, China
| | - Xin Qian
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, Guangdong, China
| | - Nancai Pei
- Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, China
| | - Dianxiang Zhang
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, 510650, Guangdong, China.
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Paudel BR, Kessler A, Shrestha M, Zhao JL, Li Q. Geographic isolation, pollination syndromes, and pollinator generalization in Himalayan
Roscoea
spp. (Zingiberaceae). Ecosphere 2019. [DOI: 10.1002/ecs2.2943] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Affiliation(s)
- Babu Ram Paudel
- Yunnan Key Laboratory of Plant Reproductive Adaption and Evolutionary Ecology Yunnan University Kunming Yunnan 650091 China
- Laboratory of Ecology and Evolutionary Biology State Key Laboratory for Conservation and Utilization of Bio‐Resources in Yunnan Yunnan University Kunming Yunnan China
- Department of Botany Prithvi Narayan Campus Tribhuvan University Pokhara Nepal
| | - André Kessler
- Ecology and Evolutionary Biology Cornell University Ithaca New York 14853 USA
| | - Mani Shrestha
- School of Media and Communications RMIT University Melbourne Victoria 3001 Australia
- Faculty of Information Technology Monash University Clayton Victoria 3800 Australia
| | - Jian Li Zhao
- Yunnan Key Laboratory of Plant Reproductive Adaption and Evolutionary Ecology Yunnan University Kunming Yunnan 650091 China
- Laboratory of Ecology and Evolutionary Biology State Key Laboratory for Conservation and Utilization of Bio‐Resources in Yunnan Yunnan University Kunming Yunnan China
| | - Qing‐Jun Li
- Yunnan Key Laboratory of Plant Reproductive Adaption and Evolutionary Ecology Yunnan University Kunming Yunnan 650091 China
- Laboratory of Ecology and Evolutionary Biology State Key Laboratory for Conservation and Utilization of Bio‐Resources in Yunnan Yunnan University Kunming Yunnan China
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9
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Song YP, Huang ZH, Huang SQ. Pollen aggregation by viscin threads in Rhododendron varies with pollinator. THE NEW PHYTOLOGIST 2019; 221:1150-1159. [PMID: 30121952 DOI: 10.1111/nph.15391] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Accepted: 07/13/2018] [Indexed: 06/08/2023]
Abstract
Pollen grains can be dispersed singly or variously aggregated in groups. Whether the evolution of pollen aggregation is driven by the pollinator remains unexplored. We hypothesize that an extensive pollen aggregation is favored under a scarcity of pollinators. Variation in pollen aggregation by viscin threads in 13 Rhododendron species was measured as it is related to pollen removal in a visit. Visitation rates of functional pollinator groups that vary in their grooming behavior were investigated in each species. Pollen deposited on stigmas in the field was also sampled. Seven Rhododendron species were infrequently pollinated by low-intensity grooming animals, including birds, butterflies and moths. The other six species were more frequently pollinated by bees with a high intensity of pollen grooming. Bird- and Lepidoptera-pollinated species produced longer pollen-connecting threads that connected more pollen grains. Phylogenetically independent contrast analysis of the 13 species showed that pollinator visitation frequency was negatively related to amounts of pollen removal per visit but not to stigmatic pollen loads. The finding of interspecific patterns in pollen removal related to pollinator visitation frequency suggests pollinator-mediated selection on pollen packaging strategies, supporting the hypothesis of floral evolution via pollen export.
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Affiliation(s)
- Yun-Peng Song
- Institute of Evolution and Ecology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Zhi-Huan Huang
- Guangxi Institute of Botany, Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guilin, 541006, China
| | - Shuang-Quan Huang
- Institute of Evolution and Ecology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
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10
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Dellinger AS, Chartier M, Fernández‐Fernández D, Penneys DS, Alvear M, Almeda F, Michelangeli FA, Staedler Y, Armbruster WS, Schönenberger J. Beyond buzz-pollination - departures from an adaptive plateau lead to new pollination syndromes. THE NEW PHYTOLOGIST 2019; 221:1136-1149. [PMID: 30368819 PMCID: PMC6492237 DOI: 10.1111/nph.15468] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 08/01/2018] [Indexed: 05/20/2023]
Abstract
Pollination syndromes describe recurring adaptation to selection imposed by distinct pollinators. We tested for pollination syndromes in Merianieae (Melastomataceae), which contain bee- (buzz-), hummingbird-, flowerpiercer-, passerine-, bat- and rodent-pollinated species. Further, we explored trait changes correlated with the repeated shifts away from buzz-pollination, which represents an 'adaptive plateau' in Melastomataceae. We used random forest analyses to identify key traits associated with the different pollinators of 19 Merianieae species and estimated the pollination syndromes of 42 more species. We employed morphospace analyses to compare the morphological diversity (disparity) among syndromes. We identified three pollination syndromes ('buzz-bee', 'mixed-vertebrate' and 'passerine'), characterized by different pollen expulsion mechanisms and reward types, but not by traditional syndrome characters. Further, we found that 'efficiency' rather than 'attraction' traits were important for syndrome circumscription. Contrary to syndrome theory, our study supports the pooling of different pollinators (hummingbirds, bats, rodents and flowerpiercers) into the 'mixed-vertebrate' syndrome, and we found that disparity was highest in the 'buzz-bee' syndrome. We conclude that the highly adaptive buzz-pollination system may have prevented shifts towards classical pollination syndromes, but provided the starting point for the evolution of a novel set of distinct syndromes, all having retained multifunctional stamens that provide pollen expulsion, reward and attraction.
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Affiliation(s)
- Agnes S. Dellinger
- Department of Botany and Biodiversity ResearchUniversity of ViennaRennweg 141030ViennaAustria
| | - Marion Chartier
- Department of Botany and Biodiversity ResearchUniversity of ViennaRennweg 141030ViennaAustria
| | - Diana Fernández‐Fernández
- Herbario Nacional del Ecuador (QCNE)Instituto Nacional de BiodiversidadRío Coca E06‐115 e Isla FernandinaQuitoEcuador
| | - Darin S. Penneys
- Department of Biology and Marine BiologyUniversity of North Carolina Wilmington601 S. College RoadWilmingtonNC28403USA
| | - Marcela Alvear
- Institute of Biodiversity Science and SustainabilityCalifornia Academy of Sciences55 Music Concourse DriveSan FranciscoCA94118‐4503USA
| | - Frank Almeda
- Institute of Biodiversity Science and SustainabilityCalifornia Academy of Sciences55 Music Concourse DriveSan FranciscoCA94118‐4503USA
| | - Fabián A. Michelangeli
- Institute of Systematic BotanyThe New York Botanical Garden2900 Southern BlvdBronxNY10458‐5126USA
| | - Yannick Staedler
- Department of Botany and Biodiversity ResearchUniversity of ViennaRennweg 141030ViennaAustria
| | - W. Scott Armbruster
- School of Biological ScienceUniversity of PortsmouthKing Henry 1 StreetPortsmouthP01 2DYUK
- Institute of Arctic BiologyUniversity of Alaska FairbanksFairbanksAK99775USA
| | - Jürg Schönenberger
- Department of Botany and Biodiversity ResearchUniversity of ViennaRennweg 141030ViennaAustria
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11
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Woźniak NJ, Sicard A. Evolvability of flower geometry: Convergence in pollinator-driven morphological evolution of flowers. Semin Cell Dev Biol 2018; 79:3-15. [DOI: 10.1016/j.semcdb.2017.09.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 09/18/2017] [Accepted: 09/19/2017] [Indexed: 01/01/2023]
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12
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Kenison EK, Weldy PY, Williams RN. There must be something in the water: assessing the behavioral responses of rusty crayfish (Orconectes rusticus) to fish and amphibian predator kairomones. J ETHOL 2017. [DOI: 10.1007/s10164-017-0529-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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13
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Huang ZH, Song YP, Huang SQ. Evidence for passerine bird pollination in Rhododendron species. AOB PLANTS 2017; 9:plx062. [PMID: 29308128 PMCID: PMC5751059 DOI: 10.1093/aobpla/plx062] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 11/07/2017] [Accepted: 11/09/2017] [Indexed: 06/02/2023]
Abstract
When insect activity is limited at low temperature, birds may be comparatively more important pollinators than insects for flowering plants. It has been thought that many large-flowered Rhododendron species are pollinated by local birds in the Himalayan regions because most of these species flower in spring at high elevation with cool atmospheric temperature. However, experimental evidence for the role of bird pollination in this hyperdiverse genus remains scarce. To examine the role of birds and insects in pollination, we observed floral visitors to 15 Rhododendron species with different floral sizes and abundant flowering individuals in the eastern Himalayas, Southwest China. To examine the role of birds and insects in female reproductive success in each species, cages were used to exclude birds but not insects from visiting flowers and net bags were used to exclude all floral visitors. Inflorescences where visitation was excluded did not produce fruits in any of the Rhododendron species, indicating that sexual reproduction in these species depended on pollinator visitation. Bird visits were generally less frequent than bee visits in the studied species. However, in the nine species on which bird visitors were observed, fruit and/or seed set were greatly reduced in inflorescences caged to exclude birds but not bees, compared to open-pollinated inflorescences. In the other six species on which bird visitation was not observed, fruit and seed set did not differ significantly between caged and open inflorescences except in one species (R. wardii). Manipulations to achieve selective exclusion of visitors demonstrated that birds could be effective pollinators for 10 out of 15 studied Rhododendron species in the eastern Himalayas. Floral characteristics of these Rhododendron species and weather conditions might favour the evolution of bird pollination systems in the East Himalayas.
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Affiliation(s)
- Zhi-Huan Huang
- Guangxi Institute of Botany, Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guilin, China
| | - Yun-Peng Song
- Institute of Evolution and Ecology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Shuang-Quan Huang
- Institute of Evolution and Ecology, School of Life Sciences, Central China Normal University, Wuhan, China
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14
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Abrahamczyk S, Lozada-Gobilard S, Ackermann M, Fischer E, Krieger V, Redling A, Weigend M. A question of data quality-Testing pollination syndromes in Balsaminaceae. PLoS One 2017; 12:e0186125. [PMID: 29036172 PMCID: PMC5642891 DOI: 10.1371/journal.pone.0186125] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 09/26/2017] [Indexed: 11/18/2022] Open
Abstract
Pollination syndromes and their predictive power regarding actual plant-animal interactions have been controversially discussed in the past. We investigate pollination syndromes in Balsaminaceae, utilizing quantitative respectively categorical data sets of flower morphometry, signal and reward traits for 86 species to test for the effect of different types of data on the test patterns retrieved. Cluster Analyses of the floral traits are used in combination with independent pollinator observations. Based on quantitative data we retrieve seven clusters, six of them corresponding to plausible pollination syndromes and one additional, well-supported cluster comprising highly divergent floral architectures. This latter cluster represents a non-syndrome of flowers not segregated by the specific data set here used. Conversely, using categorical data we obtained only a rudimentary resolution of pollination syndromes, in line with several earlier studies. The results underscore that the use of functional, exactly quanitified trait data has the power to retrieve pollination syndromes circumscribed by the specific data used. Data quality can, however, not be replaced by sheer data volume. With this caveat, it is possible to identify pollination syndromes from large datasets and to reliably extrapolate them for taxa for which direct observations are unavailable.
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Affiliation(s)
- Stefan Abrahamczyk
- Nees-Institute for Biodiversity of Plants, University of Bonn, Meckenheimer Allee 170, Bonn, Germany
- * E-mail:
| | - Sissi Lozada-Gobilard
- Nees-Institute for Biodiversity of Plants, University of Bonn, Meckenheimer Allee 170, Bonn, Germany
- Institute of Biochemistry and Biology, University of Potsdam, Maulbeerallee 1, Potsdam, Germany
| | - Markus Ackermann
- Institute for Integrated Natural Sciences–Biology, University of Koblenz-Landau, Universitätsstraße 1, Koblenz, Germany
| | - Eberhard Fischer
- Institute for Integrated Natural Sciences–Biology, University of Koblenz-Landau, Universitätsstraße 1, Koblenz, Germany
| | - Vera Krieger
- Nees-Institute for Biodiversity of Plants, University of Bonn, Meckenheimer Allee 170, Bonn, Germany
| | - Almut Redling
- Nees-Institute for Biodiversity of Plants, University of Bonn, Meckenheimer Allee 170, Bonn, Germany
| | - Maximilian Weigend
- Nees-Institute for Biodiversity of Plants, University of Bonn, Meckenheimer Allee 170, Bonn, Germany
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15
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Zhu YR, Yang M, Vamosi JC, Armbruster WS, Wan T, Gong YB. Feeding the enemy: loss of nectar and nectaries to herbivores reduces tepal damage and increases pollinator attraction in Iris bulleyana. Biol Lett 2017; 13:rsbl.2017.0271. [PMID: 28768796 DOI: 10.1098/rsbl.2017.0271] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 07/10/2017] [Indexed: 11/12/2022] Open
Abstract
Floral nectar usually functions as a pollinator reward, yet it may also attract herbivores. However, the effects of herbivore consumption of nectar or nectaries on pollination have rarely been tested. We investigated Iris bulleyana, an alpine plant that has showy tepals and abundant nectar, in the Hengduan Mountains of SW China. In this region, flowers are visited mainly by pollen-collecting pollinators and nectarivorous herbivores. We tested the hypothesis that, in I. bulleyana, sacrificing nectar and nectaries to herbivores protects tepals and thus enhances pollinator attraction. We compared rates of pollination and herbivory on different floral tissues in plants with flowers protected from nectar and nectary consumption with rates in unprotected control plants. We found that nectar and nectaries suffered more herbivore damage than did tepals in natural conditions. However, the amount of tepal damage was significantly greater in the flowers with protected nectaries than in the controls; this resulted in significant differences in pollinator visitation rates. These results provide the first evidence that floral nectar and nectaries may be 'sacrificed' to herbivores, leading to reduced damage to other floral tissues that are more important for reproduction.
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Affiliation(s)
- Ya-Ru Zhu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Min Yang
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Jana C Vamosi
- Department of Biological Sciences, University of Calgary, Calgary, Canada T2N 1N4
| | - W Scott Armbruster
- School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, UK.,Institute of Arctic Biology, University of Alaska, Fairbanks, AK 99775, USA
| | - Tao Wan
- Key Laboratory of Southern Subtropical Plant Diversity, Fairylake Botanical Garden, Shenzhen 518004, China
| | - Yan-Bing Gong
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan 430072, China
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Thompson JN, Schwind C, Friberg M. Diversification of Trait Combinations in Coevolving Plant and Insect Lineages. Am Nat 2017; 190:171-184. [PMID: 28731801 DOI: 10.1086/692164] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Closely related species often have similar traits and sometimes interact with the same species. A crucial problem in evolutionary ecology is therefore to understand how coevolving species diverge when they interact with a set of closely related species from another lineage rather than with a single species. We evaluated geographic differences in the floral morphology of all woodland star plant species (Lithophragma, Saxifragaceae) that are pollinated by Greya (Prodoxidae) moths. Flowers of each woodland star species differed depending on whether plants interact locally with one, two, or no pollinating moth species. Plants of one species grown in six different environments showed few differences in floral traits, suggesting that the geographic differences are not due significantly to trait plasticity. Greya moth populations also showed significant geographic divergence in morphology, depending on the local host and on whether the moth species co-occurred locally. Divergence in the plants and the moths involved shifts in combinations of partially correlated traits, rather than any one trait. The results indicate that the geographic mosaic of coevolution can be amplified as coevolving lineages diversify into separate species and come together in different combinations in different ecosystems.
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Opedal ØH, Albertsen E, Armbruster WS, Pérez-Barrales R, Falahati-Anbaran M, Pélabon C. Evolutionary consequences of ecological factors: pollinator reliability predicts mating-system traits of a perennial plant. Ecol Lett 2016; 19:1486-1495. [DOI: 10.1111/ele.12701] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 10/14/2016] [Indexed: 12/23/2022]
Affiliation(s)
- Øystein H. Opedal
- Centre for Biodiversity Dynamics; Department of Biology; Norwegian University of Science and Technology, NTNU; 7491 Trondheim Norway
| | - Elena Albertsen
- Centre for Biodiversity Dynamics; Department of Biology; Norwegian University of Science and Technology, NTNU; 7491 Trondheim Norway
| | - W. Scott Armbruster
- School of Biological Sciences; University of Portsmouth; King Henry Building, King Henry I Street Portsmouth PO1 2DY UK
- Department of Biology; Norwegian University of Science and Technology, NTNU; 7491 Trondheim Norway
- Institute of Arctic Biology; University of Alaska; Fairbanks AK 99775 USA
| | - Rocío Pérez-Barrales
- School of Biological Sciences; University of Portsmouth; King Henry Building, King Henry I Street Portsmouth PO1 2DY UK
| | - Mohsen Falahati-Anbaran
- School of Biology and Center of Excellence in Phylogeny of Living Organisms; University of Tehran; 14155-6455 Tehran Iran
| | - Christophe Pélabon
- Centre for Biodiversity Dynamics; Department of Biology; Norwegian University of Science and Technology, NTNU; 7491 Trondheim Norway
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Barônio GJ, Maciel AA, Oliveira AC, Kobal RO, Meireles DA, Brito VL, Rech AR. Plantas, polinizadores e algumas articulações da biologia da polinização com a teoria ecológica. RODRIGUÉSIA 2016. [DOI: 10.1590/2175-7860201667201] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Resumo A consolidação em uma área do conhecimento acontece principalmente quando as informações acerca de um determinado fato ou fenômeno são sistematizadas na forma de uma teoria explicativa, capaz de gerar novas hipóteses testáveis. Na biologia da polinização, o teste de diversas hipóteses ecológicas permitiu ampliar o entendimento sobre os processos que originam, mantêm, alteram ou ainda excluem as interações entre plantas e visitantes florais, gerando os padrões observados na natureza. Visando sintetizar esse panorama teórico e oferecer condições para que novas questões relacionadas ao funcionamento de interações de polinização sejam geradas, compilamos aqui um conjunto de 25 hipóteses, ideias e teorias ecológicas que fornecem aporte conceitual para a área. Essas ideias estão relacionadas a aspectos reprodutivos, morfológicos, cognitivos, macroecológicos e de coexistência, de acordo com a especialização das interações entre as plantas e seus polinizadores. Ao apresentarmos essas ideias principais, esperamos promover a utilização de uma abordagem teórico-conceitual explícita no planejamento e desenvolvimento de estudos em biologia da polinização. Concluímos com a expectativa de que essa contribuição direcione os estudos em biologia da polinização no Brasil e contribua para o avanço e internacionalização das pesquisas desenvolvidas no país.
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Affiliation(s)
| | | | | | | | | | | | - André R. Rech
- Universidade Federal dos Vales do Jequitinhonha e Mucuri, Brazil
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19
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Roalson EH, Roberts WR. Distinct Processes Drive Diversification in Different Clades of Gesneriaceae. Syst Biol 2016; 65:662-84. [DOI: 10.1093/sysbio/syw012] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 01/02/2016] [Indexed: 01/19/2023] Open
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20
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Bolstad GH, Hansen TF, Pélabon C, Falahati-Anbaran M, Pérez-Barrales R, Armbruster WS. Genetic constraints predict evolutionary divergence in Dalechampia blossoms. Philos Trans R Soc Lond B Biol Sci 2015; 369:20130255. [PMID: 25002700 PMCID: PMC4084540 DOI: 10.1098/rstb.2013.0255] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
If genetic constraints are important, then rates and direction of evolution should be related to trait evolvability. Here we use recently developed measures of evolvability to test the genetic constraint hypothesis with quantitative genetic data on floral morphology from the Neotropical vine Dalechampia scandens (Euphorbiaceae). These measures were compared against rates of evolution and patterns of divergence among 24 populations in two species in the D. scandens species complex. We found clear evidence for genetic constraints, particularly among traits that were tightly phenotypically integrated. This relationship between evolvability and evolutionary divergence is puzzling, because the estimated evolvabilities seem too large to constitute real constraints. We suggest that this paradox can be explained by a combination of weak stabilizing selection around moving adaptive optima and small realized evolvabilities relative to the observed additive genetic variance.
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Affiliation(s)
- Geir H Bolstad
- Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, 7491 Trondheim, Norway
| | - Thomas F Hansen
- Department of Biology, Centre for Ecological and Evolutionary Synthesis, University of Oslo, 0316 Oslo, Norway
| | - Christophe Pélabon
- Centre for Biodiversity Dynamics, Norwegian University of Science and Technology, 7491 Trondheim, Norway
| | - Mohsen Falahati-Anbaran
- Department of Biology, Norwegian University of Science and Technology, 7491 Trondheim, Norway School of Biology and Center of Excellence in Phylogeny of Living Organisms, University of Tehran, 14155-6455 Tehran, Iran
| | | | - W Scott Armbruster
- Department of Biology, Norwegian University of Science and Technology, 7491 Trondheim, Norway School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, UK Institute of Arctic Biology, University of Alaska, Fairbanks AK 99775, USA
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21
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Rosas-Guerrero V, Aguilar R, Martén-Rodríguez S, Ashworth L, Lopezaraiza-Mikel M, Bastida JM, Quesada M. A quantitative review of pollination syndromes: do floral traits predict effective pollinators? Ecol Lett 2014; 17:388-400. [DOI: 10.1111/ele.12224] [Citation(s) in RCA: 284] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 06/17/2013] [Accepted: 10/27/2013] [Indexed: 11/25/2022]
Affiliation(s)
- Víctor Rosas-Guerrero
- Centro de Investigaciones en Ecosistemas; Universidad Nacional Autónoma de México; Apartado Postal 27-3 (Xangari) 58089 Morelia Michoacán México
- Unidad Académica en Desarrollo Sustentable; Campus Costa Grande; Universidad Autónoma de Guerrero; Carretera Nacional Acapulco Zihuatanejo Km 106 + 900; Colonia Las Tunas Tecpan de Galeana Guerrero 40900 México
| | - Ramiro Aguilar
- Instituto Multidisciplinario de Biología Vegetal; Universidad Nacional de Córdoba - CONICET; C.C. 495 (5000) Córdoba Argentina
| | - Silvana Martén-Rodríguez
- Departamento de Biología Evolutiva, Instituto de Ecología A. C., Carretera Antigua a Coatepec No. 351, El Haya; Xalapa Veracruz 91070 México
- Centro Regional del Bajío, Instituto de Ecología, A. C.; Pátzcuaro, Michoacán 61600 México
| | - Lorena Ashworth
- Instituto Multidisciplinario de Biología Vegetal; Universidad Nacional de Córdoba - CONICET; C.C. 495 (5000) Córdoba Argentina
| | - Martha Lopezaraiza-Mikel
- Centro de Investigaciones en Ecosistemas; Universidad Nacional Autónoma de México; Apartado Postal 27-3 (Xangari) 58089 Morelia Michoacán México
- Unidad Académica en Desarrollo Sustentable; Campus Costa Grande; Universidad Autónoma de Guerrero; Carretera Nacional Acapulco Zihuatanejo Km 106 + 900; Colonia Las Tunas Tecpan de Galeana Guerrero 40900 México
| | - Jesús M. Bastida
- Centro de Investigaciones en Ecosistemas; Universidad Nacional Autónoma de México; Apartado Postal 27-3 (Xangari) 58089 Morelia Michoacán México
| | - Mauricio Quesada
- Centro de Investigaciones en Ecosistemas; Universidad Nacional Autónoma de México; Apartado Postal 27-3 (Xangari) 58089 Morelia Michoacán México
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de Jager ML, Ellis AG. Floral polymorphism and the fitness implications of attracting pollinating and florivorous insects. ANNALS OF BOTANY 2014; 113:213-22. [PMID: 24052554 PMCID: PMC3890383 DOI: 10.1093/aob/mct189] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 07/02/2013] [Indexed: 05/08/2023]
Abstract
BACKGROUND AND AIMS Floral polymorphism is frequently attributed to pollinator-mediated selection. Multiple studies, however, have revealed the importance of non-pollinating visitors in floral evolution. Using the polymorphic annual daisy Ursinia calenduliflora, this study investigated the importance of different insect visitors, and their effects on fitness, in the maintenance of floral polymorphism. METHODS The spatial structure of a discrete floral polymorphism was characterized based on the presence/absence of anthocyanin floret spots in U. calenduliflora. A 3-year observational study was then conducted in polymorphic populations to investigate differences in visitation rates of dominant visitors to floral morphs. Experiments were performed to explore the floral preference of male and female Megapalpus capensis (the dominant insect visitor) and their effectiveness as pollinators. Next, floral damage by antagonistic florivores and the reproductive success of the two floral morphs were surveyed in multiple populations and years. KEY RESULTS Floral polymorphism in U. calenduliflora was structured spatially, as were insect visitation patterns. Megapalpus capensis males were the dominant visitors and exhibited strong preference for the spotted morph in natural and experimental observations. While this may indicate potential fitness benefits for the spotted morph, female fitness did not differ between floral morphs. However, as M. capensis males are very efficient at exporting U. calenduliflora pollen, their preference may likely increase the reproductive fitness of the spotted morph through male fitness components. The spotted morph, however, also suffered significantly greater costs due to ovule predation by florivores than the spotless morph. CONCLUSIONS The results suggest that pollinators and florivores may potentially exert antagonistic selection that could contribute to the maintenance of floral polymorphism across the range of U. calenduliflora. The relative strength of selection imposed by each agent is potentially determined by insect community composition and abundance at each site, highlighting the importance of community context in the evolution of floral phenotypes.
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Affiliation(s)
- Marinus L. de Jager
- Botany and Zoology Department, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa
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Papadopulos AST, Powell MP, Pupulin F, Warner J, Hawkins JA, Salamin N, Chittka L, Williams NH, Whitten WM, Loader D, Valente LM, Chase MW, Savolainen V. Convergent evolution of floral signals underlies the success of Neotropical orchids. Proc Biol Sci 2013; 280:20130960. [PMID: 23804617 PMCID: PMC3712443 DOI: 10.1098/rspb.2013.0960] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
The great majority of plant species in the tropics require animals to achieve pollination, but the exact role of floral signals in attraction of animal pollinators is often debated. Many plants provide a floral reward to attract a guild of pollinators, and it has been proposed that floral signals of non-rewarding species may converge on those of rewarding species to exploit the relationship of the latter with their pollinators. In the orchid family (Orchidaceae), pollination is almost universally animal-mediated, but a third of species provide no floral reward, which suggests that deceptive pollination mechanisms are prevalent. Here, we examine floral colour and shape convergence in Neotropical plant communities, focusing on certain food-deceptive Oncidiinae orchids (e.g. Trichocentrum ascendens and Oncidium nebulosum) and rewarding species of Malpighiaceae. We show that the species from these two distantly related families are often more similar in floral colour and shape than expected by chance and propose that a system of multifarious floral mimicry—a form of Batesian mimicry that involves multiple models and is more complex than a simple one model–one mimic system—operates in these orchids. The same mimetic pollination system has evolved at least 14 times within the species-rich Oncidiinae throughout the Neotropics. These results help explain the extraordinary diversification of Neotropical orchids and highlight the complexity of plant–animal interactions.
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Pérez-Barrales R, Bolstad GH, Pélabon C, Hansen TF, Armbruster WS. Pollinators and seed predators generate conflicting selection onDalechampiablossoms. OIKOS 2013. [DOI: 10.1111/j.1600-0706.2013.20780.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Kula AAR, Dudash MR, Fenster CB. Choices and consequences of oviposition by a pollinating seed predator, Hadena ectypa (Noctuidae), on its host plant, Silene stellata (Caryophyllaceae). AMERICAN JOURNAL OF BOTANY 2013; 100:1148-54. [PMID: 23720431 DOI: 10.3732/ajb.1200636] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
PREMISE OF THE STUDY Pollinating seed predators are models for the study of mutualisms. These insects have dual effects on host-plant fitness, through pollination as adults and flower and fruit predation as larvae. A rarely examined question is whether pollinating seed-predator oviposition choices are influenced by plant floral and size traits and the potential consequences of oviposition for host-plant reproduction. • METHODS We quantified oviposition by a pollinating seed predator, Hadena ectypa, on its host, Silene stellata, to determine if oviposition was associated with specific plant traits and whether oviposition was significantly correlated with fruit initiation or flower and fruit predation over three years. We also quantified whether stigmatic pollen loads of flowers visited by Hadena that both fed on nectar and oviposited were greater than when Hadena only fed on nectar. • KEY RESULTS Hadena had significant preference for plants having flowers with long corolla tubes in all three years. Moth oviposition was correlated with other traits only in some years. Oviposition did not increase stigmatic pollen loads. We observed significant positive relationships between both oviposition and fruit initiation and oviposition and flower/fruit predation. • CONCLUSIONS Hadena ectypa oviposition choices were based consistently on floral tube length differences among individuals, and the consequences of oviposition include both fruit initiation (due to pollination while feeding on nectar prior to oviposition) and larval flower/fruit predation. The positive association between oviposition and fruit initiation may explain the long-term maintenance of facultative pollinating seed-predator interactions.
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Affiliation(s)
- Abigail A R Kula
- Behavior, Ecology, Evolution and Systematics Graduate Program, University of Maryland, College Park, MD 20742, USA.
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Armbruster WS, Lee J, Edwards ME, Baldwin BG. FLORAL PAEDOMORPHY LEADS TO SECONDARY SPECIALIZATION IN POLLINATION OF MADAGASCARDALECHAMPIA(EUPHORBIACEAE). Evolution 2012; 67:1196-203. [DOI: 10.1111/evo.12002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Pélabon C, Thöne P, Hansen TF, Armbruster WS. Signal honesty and cost of pollinator rewards in Dalechampia scandens (Euphorbiaceae). ANNALS OF BOTANY 2012; 109:1331-40. [PMID: 22628366 PMCID: PMC3359932 DOI: 10.1093/aob/mcs091] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 02/23/2012] [Indexed: 05/16/2023]
Abstract
BACKGROUND AND AIMS Most species of Dalechampia vines (Euphorbiaceae) attract bee pollinators with terpenoid resins secreted by a gland-like structure in the inflorescence. In some species, pollinating bees appear to preferentially visit inflorescences (blossoms) with large resin-producing glands, whereas in other species bees preferentially visit blossoms with large involucral bracts. In this study, the reliability of bract and gland size as signals of the quantity of resin produced in one species, D. scandens, was assessed. Whether resin secretion has a cost with respect to the number or mass of the seeds produced by a blossom was also examined. METHODS Measurements were made of bract size, gland size and the amount of resin secreted by blossoms of D. scandens maintained in a common environment, and the relationships between these traits were analysed. Resin production was also manipulated, and the effects of the manipulation were tested on seed set and seed mass. KEY RESULTS The amount of resin produced was better predicted by the size of the gland than by the size of the bract. Furthermore, when the effect of gland size was accounted for, bract size only weakly predicted the amount of resin produced. Neither an increase in resin secretion (by daily removal of the resin) nor a decrease (by removal of the resin gland) affected seed set or seed mass detectably, but resin production correlated positively with mean seed mass at the individual level once the size of the resin gland was accounted for. CONCLUSIONS Gland size is a better indicator of the amount of reward than bract size, although the latter remained an honest signal of the quantity of resin produced. Resin secretion has no detectable cost in terms of seed production, but may be condition dependent, as suggested by a positive correlation with seed mass at the individual level.
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Affiliation(s)
- Christophe Pélabon
- Centre for Conservation Biology, Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway.
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