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Maglianesi MA, Brenes E, Chaves-Elizondo N, Zuniga K, Castro Jiménez A, Barreto E, Duchenne F, Graham CH. Species morphology better predicts plant-hummingbird interactions across elevations than nectar traits. Proc Biol Sci 2024; 291:20241279. [PMID: 39317323 PMCID: PMC11421924 DOI: 10.1098/rspb.2024.1279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 07/08/2024] [Accepted: 07/29/2024] [Indexed: 09/26/2024] Open
Abstract
Species traits greatly influence interactions between plants and pollinators where floral nectar is the primary energy source fostering this mutualism. However, very little is known about how nectar traits mediate interactions in pollination networks compared with morphological traits. Here, we evaluated the role of morphological and nectar traits in shaping plant-hummingbird interaction networks along an elevation gradient. For this, we assessed patterns in floral phenotypic traits and network properties of plant species across elevations in Costa Rica. We also analysed whether plant species with generalized flower traits are ecological generalists and how morphological trait matching versus nectar traits affect interactions. We found marked variation in floral phenotypic traits and flower abundance of hummingbird-visited plant species across 10 sites along the elevation gradient. We did not find evidence for a relationship between flower morphology and nectar traits or between morphological and ecological generalization of plant species. Plant-hummingbird interaction frequency increased when the lengths of hummingbird bill and flower corolla were similar, indicating morphological matching, whereas nectar traits were unrelated to interactions. While nectar may play a difficult-to-detect secondary role within plant-hummingbird networks, our results reinforce the idea that morphological matching is an important factor in structuring ecological communities.
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Affiliation(s)
- María A Maglianesi
- Escuela de Ciencias Exactas y Naturales, Universidad Estatal a Distancia (UNED), San Pedro de Montes de Oca , San José 474-2050, Costa Rica
| | - Emanuel Brenes
- Escuela de Ciencias Exactas y Naturales, Universidad Estatal a Distancia (UNED), San Pedro de Montes de Oca , San José 474-2050, Costa Rica
| | | | - Krystal Zuniga
- Escuela de Ciencias Exactas y Naturales, Universidad Estatal a Distancia (UNED), San Pedro de Montes de Oca , San José 474-2050, Costa Rica
| | - Alejandro Castro Jiménez
- Escuela de Ciencias Exactas y Naturales, Universidad Estatal a Distancia (UNED), San Pedro de Montes de Oca , San José 474-2050, Costa Rica
| | - Elisa Barreto
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) , Birmensdorf 8903, Switzerland
| | - François Duchenne
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) , Birmensdorf 8903, Switzerland
| | - Catherine H Graham
- Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) , Birmensdorf 8903, Switzerland
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Gavini SS, Quintero C. Predation risk and floral rewards: How pollinators balance these conflicts and the consequences on plant fitness. CURRENT RESEARCH IN INSECT SCIENCE 2024; 6:100091. [PMID: 39193177 PMCID: PMC11345579 DOI: 10.1016/j.cris.2024.100091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 07/09/2024] [Accepted: 07/15/2024] [Indexed: 08/29/2024]
Abstract
Foraging behavior of pollinators is shaped by, among other factors, the conflict between maximizing resource intake and minimizing predation risk; yet, empirical studies quantifying variation in both forces are rare, compared to those investigating each separately. Here, we discuss the importance of simultaneously assessing bottom-up and top-down forces in the study of plant-pollinator interactions, and propose a conceptual and testable graphical hypothesis for pollinator foraging behavior and plant fitness outcomes as a function of varying floral rewards and predation risk. In low predation risk scenarios, no noticeable changes in pollinator foraging behavior are expected, with reward levels affecting only the activity threshold. However, as predation risk increases we propose that there is a decrease in foraging behavior, with a steeper decline as plants are more rewarding and profitable. Lastly, in high predation risk scenarios, we expect foraging to approach zero, regardless of floral rewards. Thus, we propose that pollinator foraging behavior follows an inverse S-shape curve, with more pronounced changes in foraging activity at intermediate levels of predation risk, especially in high reward systems. We present empirical evidence that is consistent with this hypothesis. In terms of the consequences for plant fitness, we propose that specialized plant-pollinator systems should be more vulnerable to increased predation risk, with a steeper and faster decline in plant fitness, compared with generalist systems, in which pollinator redundancy can delay or buffer the effect of predators. Moreover, whereas we expect that specialist systems follows a similar inverse S-shape curve, in generalist systems we propose three different scenarios as a function not only of reward level but also compatibility, mating-system, and the interplay between growth form and floral display. The incorporation of trade-offs in pollinator behavior balancing the conflicting demands between feeding and predation risk has a promising future as a key feature enabling the development of more complex foraging models.
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Affiliation(s)
- Sabrina S. Gavini
- INIBIOMA, CONICET-CRUB, Universidad Nacional del Comahue, Quintral 1250, San Carlos de Bariloche, Río Negro, Argentina
| | - Carolina Quintero
- INIBIOMA, CONICET-CRUB, Universidad Nacional del Comahue, Quintral 1250, San Carlos de Bariloche, Río Negro, Argentina
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3
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Lunau K, De Camargo MGG, Brito VLG. Pollen, anther, stamen, and androecium mimicry. PLANT BIOLOGY (STUTTGART, GERMANY) 2024; 26:349-368. [PMID: 38407440 DOI: 10.1111/plb.13628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 01/23/2024] [Indexed: 02/27/2024]
Abstract
Floral colours represent a highly diverse communication signal mainly involved in flower visitors' attraction and guidance, but also flower discrimination, filtering non-pollinators and discouraging floral antagonists. The divergent visual systems and colour preferences of flower visitors, as well as the necessity of cues for flower detection and discrimination, foster the diversity of floral colours and colour patterns. Despite the bewildering diversity of floral colour patterns, a recurrent component is a yellow UV-absorbing floral centre, and it is still not clear why this pattern is so frequent in angiosperms. The pollen, anther, stamen, and androecium mimicry (PASAM) hypothesis suggests that the system composed of the flowers possessing such yellow UV-absorbing floral reproductive structures, the flowers displaying central yellow UV-absorbing structures as floral guides, and the pollen-collecting, as well as pollen-eating, flower visitors responding to such signals constitute the world's most speciose mimicry system. In this review, we call the attention of researchers to some hypothetical PASAM systems around the globe, presenting some fascinating examples that illustrate their huge diversity. We will also present new and published data on pollen-eating and pollen-collecting pollinators' responses to PASAM structures supporting the PASAM hypothesis and will discuss how widespread these systems are around the globe. Ultimately, our goal is to promote the idea that PASAM is a plausible first approach to understanding floral colour patterns in angiosperms.
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Affiliation(s)
- K Lunau
- Faculty of Mathematics and Natural Sciences, Institute of Sensory Ecology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - M G G De Camargo
- Phenology Lab, Department of Biodiversity, Biosciences Institute, UNESP - São Paulo State University, Rio Claro, São Paulo, Brazil
| | - V L G Brito
- Instituto de Biologia, Universidade Federal de Uberlândia, Uberlândia, Minas Gerais, Brazil
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Bailes EJ, Moscrop J, Mitchell S, Dorling M, Wood T, Thomas J, Glover BJ. Bumblebee responses to variation in pollinator-attracting traits of Vicia faba flowers. Ecol Evol 2023; 13:e10617. [PMID: 37953990 PMCID: PMC10638492 DOI: 10.1002/ece3.10617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 09/25/2023] [Accepted: 10/03/2023] [Indexed: 11/14/2023] Open
Abstract
Adaptations that attract pollinators to flowers are central to the reproductive success of insect-pollinated plants, including crops. Understanding the influence of these non-rewarding traits on pollinator preference is important for our future food security by maintaining sufficient crop pollination. We have identified substantial variation in flower shape, petal size, corolla-tube length, petal spot size and floral volatile compounds among a panel of 30 genetically distinct lines of Vicia faba. Using this variation, we found that Bombus terrestris was able to distinguish between natural variation in petal spot size, floral volatile emissions and corolla-tube length. Foragers showed some innate preference for spotted flowers over non-spotted flowers and preferred shorter corolla-tube lengths over longer tubes. Our results suggest that some floral traits may have significant potential to enhance pollinator attraction to V. faba crops, particularly if paired with optimised rewards.
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Affiliation(s)
- Emily J. Bailes
- Department of Plant SciencesUniversity of CambridgeCambridgeUK
- NIABCambridgeUK
| | - Jake Moscrop
- Department of Plant SciencesUniversity of CambridgeCambridgeUK
| | - Sarah Mitchell
- Department of Plant SciencesUniversity of CambridgeCambridgeUK
| | - Matthew Dorling
- Department of Plant SciencesUniversity of CambridgeCambridgeUK
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Sasidharan R, Junker RR, Eilers EJ, Müller C. Floral volatiles evoke partially similar responses in both florivores and pollinators and are correlated with non-volatile reward chemicals. ANNALS OF BOTANY 2023; 132:1-14. [PMID: 37220889 PMCID: PMC10550281 DOI: 10.1093/aob/mcad064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 05/19/2023] [Indexed: 05/25/2023]
Abstract
BACKGROUND Plants often use floral displays to attract mutualists and prevent antagonist attacks. Chemical displays detectable from a distance include attractive or repellent floral volatile organic compounds (FVOCs). Locally, visitors perceive contact chemicals including nutrients but also deterrent or toxic constituents of pollen and nectar. The FVOC and pollen chemical composition can vary intra- and interspecifically. For certain pollinator and florivore species, responses to these compounds are studied in specific plant systems, yet we lack a synthesis of general patterns comparing these two groups and insights into potential correlations between FVOC and pollen chemodiversity. SCOPE We reviewed how FVOCs and non-volatile floral chemical displays, i.e. pollen nutrients and toxins, vary in composition and affect the detection by and behaviour of insect visitors. Moreover, we used meta-analyses to evaluate the detection of and responses to FVOCs by pollinators vs. florivores within the same plant genera. We also tested whether the chemodiversity of FVOCs, pollen nutrients and toxins is correlated, hence mutually informative. KEY RESULTS According to available data, florivores could detect more FVOCs than pollinators. Frequently tested FVOCs were often reported as pollinator-attractive and florivore-repellent. Among FVOCs tested on both visitor groups, there was a higher number of attractive than repellent compounds. FVOC and pollen toxin richness were negatively correlated, indicating trade-offs, whereas a marginal positive correlation between the amount of pollen protein and toxin richness was observed. CONCLUSIONS Plants face critical trade-offs, because floral chemicals mediate similar information to both mutualists and antagonists, particularly through attractive FVOCs, with fewer repellent FVOCs. Furthermore, florivores might detect more FVOCs, whose richness is correlated with the chemical richness of rewards. Chemodiversity of FVOCs is potentially informative of reward traits. To gain a better understanding of the ecological processes shaping floral chemical displays, more research is needed on floral antagonists of diverse plant species and on the role of floral chemodiversity in visitor responses.
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Affiliation(s)
- Rohit Sasidharan
- Department of Chemical Ecology, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Robert R Junker
- Department of Biology, Evolutionary Ecology of Plants, University of Marburg, Karl-von-Frisch-Straße 8, 35043 Marburg, Germany
- Department of Environment and Biodiversity, University of Salzburg, Kapitalgasse 4-6, 5020 Salzburg, Austria
| | - Elisabeth J Eilers
- Department of Chemical Ecology, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
- CTL GmbH Bielefeld, Krackser Straße 12, 33659 Bielefeld, Germany
| | - Caroline Müller
- Department of Chemical Ecology, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
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Maldonado M, Fornoni J, Boege K, Pérez Ishiwara R, Santos-Gally R, Domínguez CA. The role of within-plant variation in nectar production: an experimental approach. ANNALS OF BOTANY 2023; 132:95-106. [PMID: 37419457 PMCID: PMC10550272 DOI: 10.1093/aob/mcad082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Indexed: 07/09/2023]
Abstract
BACKGROUND AND AIMS Nectar, a plant reward for pollinators, can be energetically expensive. Hence, a higher investment in nectar production can lead to reduced allocation to other vital functions and/or increased geitonogamous pollination. One possible strategy employed by plants to reduce these costs is to offer variable amounts of nectar among flowers within a plant, to manipulate pollinator behaviour. Using artificial flowers, we tested this hypothesis by examining how pollinator visitation responds to inter- and intra-plant variation in nectar production, assessing how these responses impact the energetic cost per visit. METHODS We conducted a 2 × 2 factorial experiment using artificial flowers, with two levels of nectar investment (high and low sugar concentration) and two degrees of intra-plant variation in nectar concentration (coefficient of variation 0 and 20 %). The experimental plants were exposed to visits (number and type) from a captive Bombus impatiens colony, and we recorded the total visitation rate, distinguishing geitonogamous from exogamous visits. Additionally, we calculated two estimators of the energetic cost per visit and examined whether flowers with higher nectar concentrations (richer flowers) attracted more bumblebees. KEY RESULTS Plants in the variable nectar production treatment (coefficient of variation 20 %) had a greater proportion of flowers visited by pollinators, with higher rates of total, geitonogamous and exogamous visitation, compared with plants with invariable nectar production. When assuming no nectar reabsorption, variable plants incurred a lower cost per visit compared with invariable plants. Moreover, highly rewarding flowers on variable plants had higher rates of pollination visits compared with flowers with few rewards. CONCLUSIONS Intra-plant variation in nectar concentration can represent a mechanism for pollinator manipulation, enabling plants to decrease the energetic costs of the interaction while still ensuring consistent pollinator visitation. However, our findings did not provide support for the hypothesis that intra-plant variation in nectar concentration acts as a mechanism to avoid geitonogamy. Additionally, our results confirmed the hypothesis that increased visitation to variable plants is dependent on the presence of flowers with nectar concentration above the mean.
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Affiliation(s)
- Michelle Maldonado
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de MéxicoA.P. 70-275, 04510 Mexico City, Mexico
| | - Juan Fornoni
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de MéxicoA.P. 70-275, 04510 Mexico City, Mexico
| | - Karina Boege
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de MéxicoA.P. 70-275, 04510 Mexico City, Mexico
| | - Rubén Pérez Ishiwara
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de MéxicoA.P. 70-275, 04510 Mexico City, Mexico
| | - Rocío Santos-Gally
- CONAHCYT-Instituto de Ecología, Departamento de Ecología Evolutiva, Universidad Nacional Autónoma de MéxicoA.P. 70-275, 04510 Mexico City, Mexico
| | - César A Domínguez
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de MéxicoA.P. 70-275, 04510 Mexico City, Mexico
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7
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Ye ZM, Jin XF, He YD, Cao Y, Zou Y, Wang QF, Traveset A, Bergamo PJ, Yang CF. The interplay between scale, pollination niche and floral attractiveness on density-dependent plant-pollinator interactions. Oecologia 2023; 203:193-204. [PMID: 37823959 DOI: 10.1007/s00442-023-05461-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 09/25/2023] [Indexed: 10/13/2023]
Abstract
Pollinators mediate interspecific and intraspecific plant-plant indirect interactions (competition vs. facilitation) via density-dependent processes, potentially shaping the dynamics of plant communities. However, it is still unclear which ecological drivers regulate density-dependent patterns, including scale, pollination niches (i.e., the main pollinator functional group) and floral attractiveness to pollinators. In this study, we conducted three-year field observations in Hengduan Mountains of southwest China. By gathering data for more than 100 animal-pollinated plant species, we quantified the effect (positive vs. negative) of conspecific and heterospecific flower density on pollination at two scales: plot-level (4 m2) and site-level (100-5000 m2). Then, we investigated how pollination niches and floral attractiveness to pollinators (estimated here as average per-flower visitation rates) modulated density-dependent pollination interactions. Pollinator visitation depended on conspecific and heterospecific flower density, with rare plants subjected to interspecific competition at the plot-level and interspecific facilitation at the site-level. Such interspecific competition at the plot-level was stronger for plants pollinated by diverse insects, while interspecific facilitation at the site-level was stronger for bee-pollinated plants. Moreover, we also found stronger positive conspecific density-dependence for plants with lower floral attractiveness at the site-level, meaning that they become more frequently visited when abundant. Our study indicates that the role of pollination in maintaining rare plants and plant diversity depends on the balance of density-dependent processes in species-rich communities. We show here that such balance is modulated by scale, pollination niches and floral attractiveness to pollinators, indicating the context-dependency of diversity maintenance mechanisms.
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Affiliation(s)
- Zhong-Ming Ye
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Xiao-Fang Jin
- College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Yong-Deng He
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yu Cao
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Yi Zou
- Department of Health and Environmental Sciences, Xi'an Jiaotong-Liverpool University, Suzhou, 215123, China
| | - Qing-Feng Wang
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, 430074, China
| | - Anna Traveset
- Mediterranean Institute for Advanced Studies, CSIC-UIB, Miquel Marqués 21, 07190, Esporles, Mallorca, Spain
| | - Pedro J Bergamo
- Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Rio De Janeiro, 22460-030, Brazil.
| | - Chun-Feng Yang
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, 430074, China.
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan, 430074, China.
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8
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Li DF, Chen YD, Liu Z, Liang AT, Tang J, Yan XC. Staminal hairs increase pollinator attraction and pollination accuracy in Tradescantia fluminensis (Commelinaceae). AOB PLANTS 2023; 15:plad067. [PMID: 37899981 PMCID: PMC10601385 DOI: 10.1093/aobpla/plad067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 09/29/2023] [Indexed: 10/31/2023]
Abstract
Staminal hairs are the particular appendages of stamens, which may affect pollinator foraging behaviour and pollen transfer. However, experimental evidence of the functions of staminal hairs in pollination remains scarce. Here, we conducted staminal hair manipulation experiments in Tradescantia fluminensis (Commelinaceae) to investigate their effects on visitation and pollen transfer by bees. Our observations revealed that both visitation rates and visit duration of honeybees (Apis cerana) to control flowers were significantly higher than that of hairless flowers. Moreover, removing the staminal hairs significantly decreased pollen deposition by honeybees (A. cerana), but did not affect pollen removal. The staminal hair was similar in length to the stamen and the pistil of T. fluminensis. The staminal hairs provide more footholds for honeybees, and they lay prone on the staminal hairs to collect pollen, which increased the accuracy of pollination through the consistent pollen placement and pick-up on the ventral surface of honeybees. These results showed that the staminal hairs in T. fluminensis may represent an adaptation to attract pollinators and enhance pollination accuracy.
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Affiliation(s)
- Deng-Fei Li
- Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong 637002, China
| | - Yi-Dan Chen
- Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong 637002, China
| | - Zhen Liu
- Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong 637002, China
| | - Ai-Ting Liang
- Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong 637002, China
| | - Ju Tang
- College of Life Sciences, Anhui Normal University, Wuhu 241000, Anhui, China
| | - Xian-Chun Yan
- Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong 637002, China
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van der Kooi CJ, Reuvers L, Spaethe J. Honesty, reliability, and information content of floral signals. iScience 2023; 26:107093. [PMID: 37426347 PMCID: PMC10329176 DOI: 10.1016/j.isci.2023.107093] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/11/2023] Open
Abstract
Plants advertise their presence by displaying attractive flowers, which pollinators use to locate a floral reward. Understanding how floral traits scale with reward status lies at the heart of pollination biology, because it connects the different interests of plants and pollinators. Studies on plant phenotype-reward associations often use different terms and concepts, which limits developing a broader synthesis. Here, we present a framework with definitions of the key aspects of plant phenotype-reward associations and provide measures to quantify them across different species and studies. We first distinguish between cues and signals, which are often used interchangeably, but have different meanings and are subject to different selective pressures. We then define honesty, reliability, and information content of floral cues/signals and provide ways to quantify them. Finally, we discuss the ecological and evolutionary factors that determine flower phenotype-reward associations, how context-dependent and temporally variable they are, and highlight promising research directions.
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Affiliation(s)
- Casper J. van der Kooi
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands
- Department of Behavioral Physiology and Sociobiology, University of Würzburg, Würzburg, Germany
| | - Lora Reuvers
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, the Netherlands
| | - Johannes Spaethe
- Department of Behavioral Physiology and Sociobiology, University of Würzburg, Würzburg, Germany
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10
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Oscillating flower colour changes of Causonis japonica (Thunb.) Raf. (Vitaceae) linked to sexual phase changes. Sci Rep 2022; 12:19682. [PMID: 36456651 PMCID: PMC9715941 DOI: 10.1038/s41598-022-24252-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 11/11/2022] [Indexed: 12/05/2022] Open
Abstract
Flower colour change may represent an 'honest signal' for pollinators, denoting flowers with good conditions for rewards and pollination. All previously reported flower colour changes are unidirectional, except for an incomplete case in one Fabaceae species. In this study, we discovered a very rare example of complete oscillating flower colour change associated with sexual phase changes in Causonis japonica (Vitaceae). More specifically, flower discs of C. japonica exhibit an orange colour in the initial male phase then soon fade into pink with desorption of the stamens. Several hours later in the daytime of the same or the following day, with stigma maturation and style elongation, the orange flower disc colour is recovered before fading into pink again. Importantly, we found that the colour change is caused by the accumulation and the degradation of carotenoids. Moreover, nectar secretion was roughly correlated with the abovementioned colour changes. This is the first example of an apparent oscillating colour change mediated by carotenoid content alteration in flowers.
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11
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Ma B, Wu J, Shi TL, Yang YY, Wang WB, Zheng Y, Su SC, Yao YC, Xue WB, Porth I, El-Kassaby YA, Leng PS, Hu ZH, Mao JF. Lilac (Syringa oblata) genome provides insights into its evolution and molecular mechanism of petal color change. Commun Biol 2022; 5:686. [PMID: 35810211 PMCID: PMC9271065 DOI: 10.1038/s42003-022-03646-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 06/28/2022] [Indexed: 11/09/2022] Open
Abstract
Color change during flower opening is common; however, little is understood on the biochemical and molecular basis related. Lilac (Syringa oblata), a well-known woody ornamental plant with obvious petal color changes, is an ideal model. Here, we presented chromosome-scale genome assembly for lilac, resolved the flavonoids metabolism, and identified key genes and potential regulatory networks related to petal color change. The genome assembly is 1.05 Gb anchored onto 23 chromosomes, with a BUSCO score of 96.6%. Whole-genome duplication (WGD) event shared within Oleaceae was revealed. Metabolome quantification identified delphinidin-3-O-rutinoside (Dp3Ru) and cyanidin-3-O-rutinoside (Cy3Ru) as the major pigments; gene co-expression networks indicated WRKY an essential regulation factor at the early flowering stage, ERF more important in the color transition period (from violet to light nearly white), while the MBW complex participated in the entire process. Our results provide a foundation for functional study and molecular breeding in lilac.
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Affiliation(s)
- Bo Ma
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Landscape Architecture, Beijing Laboratory of Urban and Rural Ecological Environment, Bioinformatics Center, Beijing University of Agriculture, Beijing, 102206, China
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, The Key Laboratory for Silviculture and Conservation of the Ministry of Education, National Engineering Research Center of Tree Breeding and Ecological Restoration, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, College of Forestry, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Jing Wu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Landscape Architecture, Beijing Laboratory of Urban and Rural Ecological Environment, Bioinformatics Center, Beijing University of Agriculture, Beijing, 102206, China
| | - Tian-Le Shi
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, The Key Laboratory for Silviculture and Conservation of the Ministry of Education, National Engineering Research Center of Tree Breeding and Ecological Restoration, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, College of Forestry, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Yun-Yao Yang
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Landscape Architecture, Beijing Laboratory of Urban and Rural Ecological Environment, Bioinformatics Center, Beijing University of Agriculture, Beijing, 102206, China
| | - Wen-Bo Wang
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Landscape Architecture, Beijing Laboratory of Urban and Rural Ecological Environment, Bioinformatics Center, Beijing University of Agriculture, Beijing, 102206, China
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, The Key Laboratory for Silviculture and Conservation of the Ministry of Education, National Engineering Research Center of Tree Breeding and Ecological Restoration, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, College of Forestry, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Yi Zheng
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Landscape Architecture, Beijing Laboratory of Urban and Rural Ecological Environment, Bioinformatics Center, Beijing University of Agriculture, Beijing, 102206, China
| | - Shu-Chai Su
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, The Key Laboratory for Silviculture and Conservation of the Ministry of Education, National Engineering Research Center of Tree Breeding and Ecological Restoration, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, College of Forestry, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China
| | - Yun-Cong Yao
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Landscape Architecture, Beijing Laboratory of Urban and Rural Ecological Environment, Bioinformatics Center, Beijing University of Agriculture, Beijing, 102206, China
| | - Wen-Bo Xue
- BGI Genomics, BGI-Shenzhen, Shenzhen, 518083, China
| | - Ilga Porth
- Départment des Sciences du Bois et de la Forêt, Faculté de Foresterie, de Géographie et Géomatique, Université Laval, Québec, QC, G1V 0A6, Canada
| | - Yousry A El-Kassaby
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Ping-Sheng Leng
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Landscape Architecture, Beijing Laboratory of Urban and Rural Ecological Environment, Bioinformatics Center, Beijing University of Agriculture, Beijing, 102206, China.
| | - Zeng-Hui Hu
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Landscape Architecture, Beijing Laboratory of Urban and Rural Ecological Environment, Bioinformatics Center, Beijing University of Agriculture, Beijing, 102206, China.
| | - Jian-Feng Mao
- Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, The Key Laboratory for Silviculture and Conservation of the Ministry of Education, National Engineering Research Center of Tree Breeding and Ecological Restoration, Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, College of Forestry, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, 100083, China.
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Russell AL, Sanders SR, Wilson LA, Papaj DR. The Size of it: Scant Evidence That Flower Size Variation Affects Deception in Intersexual Floral Mimicry. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.724712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Mutualisms involve cooperation, but also frequently involve conflict. Plant-pollinator mutualisms are no exception. To facilitate animal pollination, flowering plants often offer pollen (their male gametes) as a food reward. Since plants benefit by maximizing pollen export to conspecific flowers, we might expect plants to cheat on pollen rewards. In intersexual floral mimicry, rewarding pollen-bearing male flowers (models) are mimicked by rewardless female flowers (mimics) on the same plant. Pollinators should therefore learn to avoid the unrewarding mimics. Plants might impede such learning by producing phenotypically variable flowers that cause bees to generalize among models and mimics during learning. In this laboratory study, we used partially artificial flowers (artificial petals, live reproductive parts) modeled after Begonia odorata to test whether variation in the size of rewarding male flowers (models) and unrewarding female flowers (mimics) affected how quickly bees learned both to recognize models and to reject mimics. Live unrewarding female flowers have 33% longer petals and have 31% greater surface area than live rewarding male flowers, which bees should easily discriminate. Yet while bees rapidly learned to reduce foraging effort on mimics, learning was not significantly affected by the degree to which flower size varied. Additionally, we found scant evidence that this was a result of bees altering response speed to maintain decision accuracy. Our study failed to provide evidence that flower size variation in intersexual floral mimicry systems exploits pollinator cognition, though we cannot rule out that other floral traits that are variable may be important. Furthermore, we propose that contrary to expectation, phenotypic variability in a Batesian mimicry system may not necessarily have significant effects on whether receivers effectively learn to discriminate models and mimics.
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