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Lev-Yadun S. Visual-, Olfactory-, and Nectar-Taste-Based Flower Aposematism. Plants (Basel) 2024; 13:391. [PMID: 38337924 PMCID: PMC10857241 DOI: 10.3390/plants13030391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 01/08/2024] [Accepted: 01/12/2024] [Indexed: 02/12/2024]
Abstract
Florivory, i.e., flower herbivory, of various types is common and can strongly reduce plant fitness. Flowers suffer two very different types of herbivory: (1) the classic herbivory of consuming tissues and (2) nectar theft. Unlike the non-reversibility of consumed tissues, nectar theft, while potentially reducing a plant's fitness by lowering its attraction to pollinators, can, in various cases, be fixed quickly by the production of additional nectar. Therefore, various mechanisms to avoid or reduce florivory have evolved. Here, I focus on one of the flowers' defensive mechanisms, aposematism, i.e., warning signaling to avoid or at least reduce herbivory via the repelling of herbivores. While plant aposematism of various types was almost ignored until the year 2000, it is a common anti-herbivory defense mechanism in many plant taxa, operating visually, olfactorily, and, in the case of nectar, via a bitter taste. Flower aposematism has received only very little focused attention as such, and many of the relevant publications that actually demonstrated herbivore repellence and avoidance learning following flower signaling did not refer to repellence as aposematism. Here, I review what is known concerning visual-, olfactory-, and nectar-taste-based flower aposematism, including some relevant cases of mimicry, and suggest some lines for future research.
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Affiliation(s)
- Simcha Lev-Yadun
- Department of Biology & Environment, Faculty of Natural Sciences, University of Haifa-Oranim, Tivon 36006, Israel
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2
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Costa A, Moré M, Sérsic AN, Cocucci AA, Drewniak ME, Izquierdo JV, Coetzee A, Pauw A, Traveset A, Paiaro V. Floral colour variation of Nicotiana glauca in native and non-native ranges: Testing the role of pollinators' perception and abiotic factors. Plant Biol (Stuttg) 2023; 25:403-410. [PMID: 36744723 DOI: 10.1111/plb.13509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
Invasive plants displaying disparate pollination environments and abiotic conditions in native and non-native ranges provide ideal systems to test the role of different ecological factors driving flower colour variation. We quantified corolla reflectance of the ornithophilous South American Nicotiana glauca in native populations, where plants are pollinated by hummingbirds, and in populations from two invaded regions: South Africa, where plants are pollinated by sunbirds, and the Balearic island of Mallorca, where plants reproduce by selfing. Using visual modelling we examined how corolla reflectance could be perceived by floral visitors present in each region. Through Mantel tests we assessed a possible association between flower colour and different abiotic factors. Corolla reflectance variation (mainly along medium to long wavelengths, i.e. human green-yellow to red colours) was greater among studied regions than within them. Flower colour was more similar between South America and South Africa, which share birds as pollinators. Within invaded regions, corolla reflectance variation was lower in South Africa, where populations could not be distinguished from each other by sunbirds, than in Spain, where populations could be distinguished from each other by their occasional visitors. Differences in corolla colour among populations were partially associated with differences in temperature. Our findings suggest that shifts in flower colour of N. glauca across native and invaded ranges could be shaped by changes in both pollination environment and climatic factors. This is the first study on plant invasions considering visual perception of different pollinators and abiotic drivers of flower colour variation.
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Affiliation(s)
- A Costa
- Instituto Multidisciplinario de Biología Vegetal (CONICET-UNC), Córdoba, Argentina
| | - M Moré
- Instituto Multidisciplinario de Biología Vegetal (CONICET-UNC), Córdoba, Argentina
| | - A N Sérsic
- Instituto Multidisciplinario de Biología Vegetal (CONICET-UNC), Córdoba, Argentina
| | - A A Cocucci
- Instituto Multidisciplinario de Biología Vegetal (CONICET-UNC), Córdoba, Argentina
| | - M E Drewniak
- Instituto Multidisciplinario de Biología Vegetal (CONICET-UNC), Córdoba, Argentina
| | - J V Izquierdo
- Instituto Multidisciplinario de Biología Vegetal (CONICET-UNC), Córdoba, Argentina
| | - A Coetzee
- Fitz Patrick Institute of African Ornithology, DSI-NRF Centre of Excellence, University of Cape Town, Rondebosch, South Africa
| | - A Pauw
- Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - A Traveset
- Instituto Mediterráneo de Estudios Avanzados (CSIC, UIB), Mallorca, Balearic Islands, Spain
| | - V Paiaro
- Instituto Multidisciplinario de Biología Vegetal (CONICET-UNC), Córdoba, Argentina
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3
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Johnson SD. Bird pollination. Curr Biol 2022; 32:R1059-R1060. [DOI: 10.1016/j.cub.2022.06.081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Basso-Alves JP, da Silva RF, Coimbra G, Leitão SG, de Rezende CM, Bizzo HR, Freitas L, Paulino JV, Mansano VDF. Heteromorphic stamens are differentially attractive in Swartzia (Fabaceae). AoB Plants 2022; 14:plac041. [PMID: 36267642 PMCID: PMC9575666 DOI: 10.1093/aobpla/plac041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 09/08/2022] [Indexed: 06/16/2023]
Abstract
The division of labour hypothesis between stamens has explained the evolution of divergent functions between dimorphic stamens in the same flower. However, little is known about whether the distinct type of stamens differs in attractiveness to pollinators. Therefore, we investigate whether the two types of stamens commonly found in Swartzia have different visual and olfactory attractants. We performed observations of anthesis dynamics, registration and collection of floral visitors, measurements of reflectance of floral parts and chemical analysis of the volatile organic compounds of the floral parts of two species, S. flaemingii and S. simplex. Both species have two distinct sets of stamens: one with smaller and abundant stamens in the centre of the flower and the other with fewer but larger abaxial stamens. The sets differ in UV reflectance (only S. simplex) and exhibit a distinct chromatic contrast. Concerning olfactory attractiveness, aliphatic compounds make up most of the odour of the two species, both whole flowers and most of their floral organs. On the other hand, only S. simplex presented apocarotenoids (as ionones) and benzenoids. Furthermore, there are differences in the proportion of volatiles emitted by the stamen in both cases, as the high proportion of sesquiterpenes among the smaller stamens compared to the larger ones. In conclusion, the two types of stamens found in S. flaemingii and S. simplex show a distinct attractiveness. In addition, our data have demonstrated diverse ways of differential attractiveness both between distinct stamens set per flower and between the two species from the same pollen flowers genus.
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Affiliation(s)
| | - Rafael Ferreira da Silva
- Departamento de Química Orgânica/GQO, Instituto de Química, Universidade Federal Fluminense (UFF), Niterói, RJ 24020141, Brazil
| | - Gabriel Coimbra
- Programa de Pós-Graduação em Botânica, Escola Nacional de Botânica Tropical, Jardim Botânico do Rio de Janeiro, Rio de Janeiro, RJ 22460-036, Brazil
- Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, DIPEQ-JBRJ, Rio de Janeiro, RJ 22460-030, Brazil
| | - Suzana Guimarães Leitão
- Departamento de Produtos Naturais e Alimentos, Faculdade de Farmácia, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ 21941-902, Brazil
| | - Claudia Moraes de Rezende
- Instituto de Química, Centro de Tecnologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ 22945970, Brazil
| | | | - Leandro Freitas
- Programa de Pós-Graduação em Botânica, Escola Nacional de Botânica Tropical, Jardim Botânico do Rio de Janeiro, Rio de Janeiro, RJ 22460-036, Brazil
- Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, DIPEQ-JBRJ, Rio de Janeiro, RJ 22460-030, Brazil
| | - Juliana Villela Paulino
- Programa de Pós-Graduação em Botânica, Escola Nacional de Botânica Tropical, Jardim Botânico do Rio de Janeiro, Rio de Janeiro, RJ 22460-036, Brazil
- Departamento de Produtos Naturais e Alimentos, Faculdade de Farmácia, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ 21941-902, Brazil
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Valderrama E, Landis JB, Skinner D, Maas PJM, Maas-van de Kramer H, André T, Grunder N, Sass C, Pinilla-Vargas M, Guan CJ, Phillips HR, de Almeida AMR, Specht CD. The genetic mechanisms underlying the convergent evolution of pollination syndromes in the Neotropical radiation of Costus L. Front Plant Sci 2022; 13:874322. [PMID: 36161003 PMCID: PMC9493542 DOI: 10.3389/fpls.2022.874322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 06/27/2022] [Indexed: 06/16/2023]
Abstract
Selection together with variation in floral traits can act to mold floral form, often driven by a plant's predominant or most effective pollinators. To investigate the evolution of traits associated with pollination, we developed a phylogenetic framework for evaluating tempo and mode of pollination shifts across the genus Costus L., known for its evolutionary toggle between traits related to bee and bird pollination. Using a target enrichment approach, we obtained 957 loci for 171 accessions to expand the phylogenetic sampling of Neotropical Costus. In addition, we performed whole genome resequencing for a subset of 20 closely related species with contrasting pollination syndromes. For each of these 20 genomes, a high-quality assembled transcriptome was used as reference for consensus calling of candidate loci hypothesized to be associated with pollination-related traits of interest. To test for the role these candidate genes may play in evolutionary shifts in pollinators, signatures of selection were estimated as dN/dS across the identified candidate loci. We obtained a well-resolved phylogeny for Neotropical Costus despite conflict among gene trees that provide evidence of incomplete lineage sorting and/or reticulation. The overall topology and the network of genome-wide single nucleotide polymorphisms (SNPs) indicate that multiple shifts in pollination strategy have occurred across Costus, while also suggesting the presence of previously undetected signatures of hybridization between distantly related taxa. Traits related to pollination syndromes are strongly correlated and have been gained and lost in concert several times throughout the evolution of the genus. The presence of bract appendages is correlated with two traits associated with defenses against herbivory. Although labellum shape is strongly correlated with overall pollination syndrome, we found no significant impact of labellum shape on diversification rates. Evidence suggests an interplay of pollination success with other selective pressures shaping the evolution of the Costus inflorescence. Although most of the loci used for phylogenetic inference appear to be under purifying selection, many candidate genes associated with functional traits show evidence of being under positive selection. Together these results indicate an interplay of phylogenetic history with adaptive evolution leading to the diversification of pollination-associated traits in Neotropical Costus.
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Affiliation(s)
- Eugenio Valderrama
- School of Integrative Plant Science, Section of Plant Biology and the L.H. Bailey Hortorium, Cornell University, Ithaca, NY, United States
| | - Jacob B. Landis
- School of Integrative Plant Science, Section of Plant Biology and the L.H. Bailey Hortorium, Cornell University, Ithaca, NY, United States
- BTI Computational Biology Center, Boyce Thompson Institute, Ithaca, NY, United States
| | - Dave Skinner
- Le Jardin Ombragé, Tallahassee, FL, United States
| | - Paul J. M. Maas
- Section Botany, Naturalis Biodiversity Center, Leiden, Netherlands
| | | | - Thiago André
- Departamento de Botânica, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF, Brazil
| | - Nikolaus Grunder
- Department of Biological Sciences, California State University, East Bay, Hayward, CA, United States
| | - Chodon Sass
- University and Jepson Herbaria, University of California, Berkeley, Berkeley, CA, United States
| | - Maria Pinilla-Vargas
- School of Integrative Plant Science, Section of Plant Biology and the L.H. Bailey Hortorium, Cornell University, Ithaca, NY, United States
| | - Clarice J. Guan
- School of Integrative Plant Science, Section of Plant Biology and the L.H. Bailey Hortorium, Cornell University, Ithaca, NY, United States
| | - Heather R. Phillips
- School of Integrative Plant Science, Section of Plant Biology and the L.H. Bailey Hortorium, Cornell University, Ithaca, NY, United States
| | | | - Chelsea D. Specht
- School of Integrative Plant Science, Section of Plant Biology and the L.H. Bailey Hortorium, Cornell University, Ithaca, NY, United States
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Hou QZ, Shao WJ, Ehmet N, Yang G, Zhong YQ, Min WR, Xu YF, Gao RC. The Biomechanical Screening Game between Visitor Power and Staminode Operative Strength of Delphinium caeruleum (Ranunculaceae). Plants 2022; 11:plants11172319. [PMID: 36079701 PMCID: PMC9459735 DOI: 10.3390/plants11172319] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 08/27/2022] [Accepted: 08/29/2022] [Indexed: 11/28/2022]
Abstract
During the evolution of angiosperm flowers, some floral traits may undergo certain changes in order to participate in screening. The stamens and pistils of Delphinium caeruleum are covered by two “door-like” staminodes, the evolutionary function of which, however, is quite unknown. In this study, we investigated whether D. caeruleum staminodes acted as visitor filters by assessing the respective strengths of staminodes and visitor insects (six bee species). We measured the operative strength required to open the staminodes and the strength that insects were capable of exerting using a biological tension sensor. Furthermore, we compared the strength required to open staminodes at different phases of the flowering period (male and female phases) and the strength of different visitors (visitors and non-visitors of D. caeruleum). The results showed that the strength needed to open staminodes in the male phase was significantly higher than that in the female phase. There was no significant difference between the strength exerted by visitors and required by staminodes of D. caeruleum in the male phase, but the visitor strength was significantly higher than that required to open staminodes in the female phase flowers. The strength of non-visitors was significantly lower than that required to open staminodes in the male phase. Furthermore, there was a significant positive association between the strength and the body weight of the bees. These results highlighted the observation that only strong visitors could press the two staminodes to access the sex organs and achieve successful pollination. Furthermore, these results revealed the function of pollinator screening by the staminodes of D. caeruleum. The biomechanical approach to the study of flowers allowed us to address relevant ecological and evolutionary questions of the plant–pollinator interaction and explore the functional modules within the flower structure in other plant species.
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Affiliation(s)
- Qin-Zheng Hou
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
- Correspondence: ; Tel.: +86-189-1983-2688
| | - Wen-Juan Shao
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
- Physical Chemistry Biology Teaching and Research Group, Lanzhou Oriental School, Lanzhou 730070, China
| | - Nurbiye Ehmet
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Guang Yang
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Yu-Qin Zhong
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Wen-Rui Min
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Yi-Fan Xu
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
| | - Ruo-Chun Gao
- College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
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León‐Osper M, Narbona E. Unravelling the mystery of red flowers in the Mediterranean Basin: How to be conspicuous in a place dominated by hymenopteran pollinators. Funct Ecol 2022. [DOI: 10.1111/1365-2435.14166] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Melissa León‐Osper
- Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide Sevilla España
| | - Eduardo Narbona
- Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide Sevilla España
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Mundi O, Awa Ii T, Chmel K, Ewome FL, Uceda-Gómez G, Janečková P, Janeček Š. The ornithophily of Impatiens sakeriana does not guarantee a preference by sunbirds. Biol J Linn Soc Lond 2022. [DOI: 10.1093/biolinnean/blac083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
In recent decades, the tight mutual specialization between nectarivorous birds and ornithophilous plants has been questioned, and instead, high degrees of generalization and interaction asymmetry have been highlighted. Here, we studied interactions among two sunbirds and four plant species in two Mount Cameroon forests, with two plant species from each forest. First, we investigated whether sunbirds differ in frequencies of visitation to target plant species in natural conditions. Second, using a cage experiment, we investigated whether sunbirds prefer various plant species, plants with which they are more familiar and that occur in the habitat where they were caught and/or the only studied ornithophilous plant, Impatiens sakeriana. In natural conditions, the short-billed sunbird, Cinnyris reichenowi, fed more on flowers with shorter tubes than the long-billed sunbird, Cyanomitra oritis. Likewise, sunbirds differed in their experimental preferences. Local plants were generally preferred. This was most obvious in the case of I. sakeriana, which was often visited by both sunbirds, but only in the habitat where it grows naturally. This study supports the importance of associative learning. Together with other studies, we suggest that the signalling traits of flowers with bird pollination syndromes evolved to filter out other visitors rather than to attract bird pollinators.
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Affiliation(s)
- Onella Mundi
- Laboratory of Applied Biology and Ecology, Faculty of Science, University of Dschang , PO Box 67, Dschang, West Region , Cameroon
| | - Taku Awa Ii
- Laboratory of Applied Biology and Ecology, Faculty of Science, University of Dschang , PO Box 67, Dschang, West Region , Cameroon
| | - Kryštof Chmel
- Department of Ecology, Faculty of Science, Charles University , Viničná 7, CZ-128 44 Praha 2 , Czech Republic
| | - Francis Luma Ewome
- Department of Ecology, Faculty of Science, Charles University , Viničná 7, CZ-128 44 Praha 2 , Czech Republic
| | - Guillermo Uceda-Gómez
- Department of Ecology, Faculty of Science, Charles University , Viničná 7, CZ-128 44 Praha 2 , Czech Republic
| | - Petra Janečková
- Department of Ecology, Faculty of Science, Charles University , Viničná 7, CZ-128 44 Praha 2 , Czech Republic
| | - Štěpán Janeček
- Department of Ecology, Faculty of Science, Charles University , Viničná 7, CZ-128 44 Praha 2 , Czech Republic
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van der Kooi CJ, Spaethe J. Caution with colour calculations: spectral purity is a poor descriptor of flower colour visibility. Ann Bot 2022; 130:1-9. [PMID: 35726715 PMCID: PMC9295922 DOI: 10.1093/aob/mcac069] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 05/26/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND The colours of flowers are of key interest to plant and pollination biologists. An increasing number of studies have investigated the importance of saturation of flower colours (often called 'spectral purity' or 'chroma') for visibility to pollinators, but the conceptual, physiological and behavioural foundations for these metrics as well as the calculations used rest on slender foundations. METHODS We discuss the caveats of colour attributes that are derived from human perception, and in particular spectral purity and chroma, as variables in flower colour analysis. We re-analysed seven published datasets encompassing 774 measured reflectance spectra to test for correlations between colour contrast, spectral purity and chroma. MAIN FINDINGS AND CONCLUSIONS We identify several concerns with common calculation procedures in animal colour spaces. Studies on animal colour vision provide no ground to assume that any pollinator perceives (or responds to) saturation, chroma or spectral purity in the way humans do. A re-analysis of published datasets revealed that values for colour contrast between flowers and their background are highly correlated with measures for spectral purity and chroma, which invalidates treating these factors as independent variables as is currently commonplace. Strikingly, spectral purity and chroma - both of which are metrics for saturation and are often used synonymously - are not correlated at all. We conclude that alternative, behaviourally validated metrics for the visibility of flowers to pollinators, such as colour contrast and achromatic contrast, are better in understanding the role of flower colour in plant-pollinator signalling.
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Affiliation(s)
| | - Johannes Spaethe
- Department of Behavioral Physiology and Sociobiology, University of Würzburg, Germany
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Xiang WQ, Malabrigo PL, Tang L, Ren MX. Limited-Distance Pollen Dispersal and Low Paternal Diversity in a Bird-Pollinated Self-Incompatible Tree. Front Plant Sci 2022; 13:806217. [PMID: 35283871 PMCID: PMC8914170 DOI: 10.3389/fpls.2022.806217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 01/25/2022] [Indexed: 06/14/2023]
Abstract
Bird pollination in Asia is regarded as an uncommon phenomenon and, therefore, only a few investigations on mating pattern and paternity in fruits of Asian bird-pollinated plants have been conducted. Here, we examined spatial genetic structure, pollen dispersal, and multiple paternity in a natural population of Bombax ceiba (B. ceiba) (Malvaceae) in Hainan Island, South China, using simple sequence repeat (SSR) markers. A low genetic diversity (H e = 0.351 ± 0.0341 and 0.389 ± 0.043, respectively, for adults and offspring) and bottleneck effects were observed. Genetic kinship was significant within 400 m or in 1,800-3,800 m. Both the mating pattern and paternity analysis confirmed obligate xenogamy and a low multiple paternity in B. ceiba. There was a strongly negative relationship between the frequency of matings and the distance between mating pairs. The average pollen dispersal distance was 202.89 ± 41.01 m (mean ± SE) and the farthest distance of > 1 km was recorded. Realized mating events showed an extremely leptokurtic distribution within 1,200 m, suggesting that the pollen dispersal distance was consistent with the optimal foraging theory of generalist birds such as Zosterops spp. and Pycnonotus spp. Paternity per tree ranged from two to six and the average effective number of pollen donors per maternal plant was 3.773, suggesting a low level of paternity diversity as compared to other bird-pollinated plants. We concluded that optimal foraging behavior by generalist birds could explain the leptokurtic pollen dispersal distribution and predominantly near-neighbor matings in B. ceiba. The limited pollen dispersal distance and low multiple paternity were consistent with low fruit setting rate (3.27 ± 0.93%) in this self-incompatible tree, which was caused mainly by the restricted flight distance of birds and human disturbances. Low genetic diversity and significant spatial genetic structure might have largely resulted from logging and human collection of fruits.
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Affiliation(s)
- Wen-Qian Xiang
- Key Laboratory of Ministry of Education for Genetics and Germplasm Innovation of Tropical Special Trees and Ornamental Plants, Hainan University, Haikou, China
- Center for Terrestrial Biodiversity of the South China Sea, Hainan University, Haikou, China
| | - Pastor L. Malabrigo
- Department of Forest Biological Sciences, College of Forestry and Natural Resources, University of the Philippines Los Baños, Los Baños, Philippines
| | - Liang Tang
- Key Laboratory of Ministry of Education for Genetics and Germplasm Innovation of Tropical Special Trees and Ornamental Plants, Hainan University, Haikou, China
- Center for Terrestrial Biodiversity of the South China Sea, Hainan University, Haikou, China
| | - Ming-Xun Ren
- Key Laboratory of Ministry of Education for Genetics and Germplasm Innovation of Tropical Special Trees and Ornamental Plants, Hainan University, Haikou, China
- Center for Terrestrial Biodiversity of the South China Sea, Hainan University, Haikou, China
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Abrahamczyk S, Weigend M, Becker K, Dannenberg LS, Eberz J, Atella‐Hödtke N, Steudel B. Influence of plant reproductive systems on the evolution of hummingbird pollination. Ecol Evol 2022; 12:e8621. [PMID: 35222976 PMCID: PMC8853967 DOI: 10.1002/ece3.8621] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 01/20/2022] [Accepted: 01/25/2022] [Indexed: 01/10/2023] Open
Abstract
Many hummingbird‐pollinated plant species evolved from bee‐pollinated ancestors independently in many different habitats in North and South America. The mechanisms leading to these transitions are not completely understood. We conducted pollination and germination experiments and analyzed additional reproductive traits in three sister species pairs of which one species is bee‐ and the other hummingbird‐pollinated. All hummingbird‐pollinated species showed higher seed set and germination rates in cross‐pollinated than in self‐pollinated flowers. In the self‐compatible, bee‐pollinated sister species this difference did not exist. As expected, seed set and germination rate were higher after cross‐pollination in the largely self‐incompatible genus Penstemon independently of the pollination syndrome. However, the bird‐pollinated species produce only half of the amount of ovules and pollen grains per flower compared to the bee‐pollinated sister species. This indicates that hummingbird pollination is much more efficient in self‐incompatible populations because hummingbirds waste less pollen and provide higher outcrossing rates. Therefore, hummingbird pollination is less resource costly. Overall, we suggest that hummingbirds may increase the reproductive success compared to bees, influencing the evolution of hummingbird pollination in ecosystems with diverse bee assemblages.
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Affiliation(s)
- Stefan Abrahamczyk
- Nees Institute for Biodiversity of Plants University of Bonn Bonn Germany
| | - Maximilian Weigend
- Nees Institute for Biodiversity of Plants University of Bonn Bonn Germany
| | - Katrin Becker
- Nees Institute for Biodiversity of Plants University of Bonn Bonn Germany
| | | | - Judith Eberz
- Nees Institute for Biodiversity of Plants University of Bonn Bonn Germany
| | | | - Bastian Steudel
- Health and Environmental Sciences Xi'an Jiaotong‐Liverpool University Suzhou China
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Bergamo PJ, Streher NS, Zambon V, Wolowski M, Sazima M. Pollination generalization and reproductive assurance by selfing in a tropical montane ecosystem. Naturwissenschaften 2021; 108:50. [PMID: 34626232 DOI: 10.1007/s00114-021-01764-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 09/22/2021] [Accepted: 09/29/2021] [Indexed: 10/20/2022]
Abstract
Pollination and reproduction are important processes for understanding plant community dynamics. Information regarding pollination and reproduction is urgent for threatened ecosystems, such as tropical montane ecosystems. In tropical mountains, pollination patterns are expected to conform to the reproductive assurance theory (due to low pollinator activity) and old, climatically buffered and infertile landscapes (OCBIL) theory (due to restricted plant range size). For 82 plant species of the Itatiaia National Park (including endemic and endangered species), we evaluated at least one of the following features: pollinator identity, flower color and size, flowering phenology, and pollinator dependence. Most plant species (ca. 60%) were pollinated by two or more functional groups of pollinators (generalized pollination), with high importance of flies as pollinators. There was low pollinator activity overall (less than one visit per flower per hour). Notably, the invasive honeybee Apis mellifera L. performed half of the visits to this entire plant community, suggesting an impact on the native pollinator fauna and consequently on the native flora. Most endemic plants were generalized with white and small flowers, while endangered species were pollination-specialized with colorful and large flowers. Thus, endangered species are susceptible to changes in pollinator fauna. Flowering seasonality reflected the importance of climatic constraints in this environment. One-third of the plant species were autogamous. Our data suggest that pollinator scarcity may have promoted reproductive assurance strategies such as generalization and pollinator independence. Our community-level study highlighted consistent pollination patterns for tropical mountains and emphasized threats for specialized endangered species.
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Narbona E, del Valle JC, Arista M, Buide ML, Ortiz PL. Major Flower Pigments Originate Different Colour Signals to Pollinators. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.743850] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Flower colour is mainly due to the presence and type of pigments. Pollinator preferences impose selection on flower colour that ultimately acts on flower pigments. Knowing how pollinators perceive flowers with different pigments becomes crucial for a comprehensive understanding of plant-pollinator communication and flower colour evolution. Based on colour space models, we studied whether main groups of pollinators, specifically hymenopterans, dipterans, lepidopterans and birds, differentially perceive flower colours generated by major pigment groups. We obtain reflectance data and conspicuousness to pollinators of flowers containing one of the pigment groups more frequent in flowers: chlorophylls, carotenoids and flavonoids. Flavonoids were subsequently classified in UV-absorbing flavonoids, aurones-chalcones and the anthocyanins cyanidin, pelargonidin, delphinidin, and malvidin derivatives. We found that flower colour loci of chlorophylls, carotenoids, UV-absorbing flavonoids, aurones-chalcones, and anthocyanins occupied different regions of the colour space models of these pollinators. The four groups of anthocyanins produced a unique cluster of colour loci. Interestingly, differences in colour conspicuousness among the pigment groups were almost similar in the bee, fly, butterfly, and bird visual space models. Aurones-chalcones showed the highest chromatic contrast values, carotenoids displayed intermediate values, and chlorophylls, UV-absorbing flavonoids and anthocyanins presented the lowest values. In the visual model of bees, flowers with UV-absorbing flavonoids (i.e., white flowers) generated the highest achromatic contrasts. Ours findings suggest that in spite of the almost omnipresence of floral anthocyanins in angiosperms, carotenoids and aurones-chalcones generates higher colour conspicuousness for main functional groups of pollinators.
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Chmel K, Ewome FL, Gómez GU, Klomberg Y, Mertens JEJ, Tropek R, Janeček Š. Bird pollination syndrome is the plant's adaptation to ornithophily, but nectarivorous birds are not so selective. OIKOS 2021. [DOI: 10.1111/oik.08052] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Kryštof Chmel
- Dept. of Ecology, Faculty of Science, Charles Univ. Viničná Prague Czechia
- Inst. of Entomology, Biology Centre, Czech Academy of Sciences Branišovská České Budějovice Czechia
| | | | | | - Yannick Klomberg
- Dept. of Ecology, Faculty of Science, Charles Univ. Viničná Prague Czechia
- Naturalis Biodiversity Center Darwinweg Leiden the Netherlands
| | - Jan E. J. Mertens
- Dept. of Ecology, Faculty of Science, Charles Univ. Viničná Prague Czechia
| | - Robert Tropek
- Dept. of Ecology, Faculty of Science, Charles Univ. Viničná Prague Czechia
- Inst. of Entomology, Biology Centre, Czech Academy of Sciences Branišovská České Budějovice Czechia
| | - Štěpán Janeček
- Dept. of Ecology, Faculty of Science, Charles Univ. Viničná Prague Czechia
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Dyer AG, Jentsch A, Burd M, Garcia JE, Giejsztowt J, Camargo MGG, Tjørve E, Tjørve KMC, White P, Shrestha M. Fragmentary Blue: Resolving the Rarity Paradox in Flower Colors. Front Plant Sci 2021; 11:618203. [PMID: 33552110 PMCID: PMC7859648 DOI: 10.3389/fpls.2020.618203] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 12/17/2020] [Indexed: 05/05/2023]
Abstract
Blue is a favored color of many humans. While blue skies and oceans are a common visual experience, this color is less frequently observed in flowers. We first review how blue has been important in human culture, and thus how our perception of blue has likely influenced the way of scientifically evaluating signals produced in nature, including approaches as disparate as Goethe's Farbenlehre, Linneaus' plant taxonomy, and current studies of plant-pollinator networks. We discuss the fact that most animals, however, have different vision to humans; for example, bee pollinators have trichromatic vision based on UV-, Blue-, and Green-sensitive photoreceptors with innate preferences for predominantly short-wavelength reflecting colors, including what we perceive as blue. The subsequent evolution of blue flowers may be driven by increased competition for pollinators, both because of a harsher environment (as at high altitude) or from high diversity and density of flowering plants (as in nutrient-rich meadows). The adaptive value of blue flowers should also be reinforced by nutrient richness or other factors, abiotic and biotic, that may reduce extra costs of blue-pigments synthesis. We thus provide new perspectives emphasizing that, while humans view blue as a less frequently evolved color in nature, to understand signaling, it is essential to employ models of biologically relevant observers. By doing so, we conclude that short wavelength reflecting blue flowers are indeed frequent in nature when considering the color vision and preferences of bees.
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Affiliation(s)
- Adrian G. Dyer
- School of Media and Communication, RMIT University, Melbourne, VIC, Australia
| | - Anke Jentsch
- Department of Disturbance Ecology, Bayreuth Center for Ecology and Environmental Research, University of Bayreuth, Bayreuth, Germany
| | - Martin Burd
- School of Biological Sciences, Monash University, Melbourne, VIC, Australia
| | - Jair E. Garcia
- School of Media and Communication, RMIT University, Melbourne, VIC, Australia
| | - Justyna Giejsztowt
- Department of Disturbance Ecology, Bayreuth Center for Ecology and Environmental Research, University of Bayreuth, Bayreuth, Germany
| | - Maria G. G. Camargo
- Phenology Lab, Biosciences Institute, Department of Biodiversity, UNESP – São Paulo State University, São Paulo, Brazil
| | - Even Tjørve
- Inland Norway University of Applied Sciences, Lillehammer, Norway
| | | | - Peter White
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Mani Shrestha
- School of Media and Communication, RMIT University, Melbourne, VIC, Australia
- Faculty of Information Technology, Monash University, Melbourne, VIC, Australia
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