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Scaccabarozzi D, Guzzetti L, Pioltelli E, Brundrett M, Aromatisi A, Polverino G, Vallejo-Marin M, Cozzolino S, Ren ZX. Evidence of introduced honeybees (Apis mellifera) as pollen wasters in orchid pollination. Sci Rep 2024; 14:14076. [PMID: 38890342 PMCID: PMC11189403 DOI: 10.1038/s41598-024-64218-x] [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: 04/03/2024] [Accepted: 06/06/2024] [Indexed: 06/20/2024] Open
Abstract
Biological invasions threaten global biodiversity, altering landscapes, ecosystems, and mutualistic relationships like pollination. Orchids are one of the most threatened plant families, yet the impact of invasive bees on their reproduction remains poorly understood. We conduct a global literature survey on the incidence of invasive honeybees (Apis mellifera) on orchid pollination, followed by a study case on Australian orchids. Our literature survey shows that Apis mellifera is the primary alien bee visiting orchids worldwide. However, in most cases, introduced honeybees do not deposit orchid pollen. We also test the extent to which introduced honeybees affect orchid pollination using Diuris brumalis and D. magnifica. Diuris brumalis shows higher fruit set and pollination in habitats with both native and invasive bees compared to habitats with only introduced bees. Male and female reproductive success in D. magnifica increases with native bee abundance, while conversely pollinator efficiency decreases with honeybee abundance and rises with habitat size. Our results suggest that introduced honeybees are likely involved in pollen removal but do not effectively deposit orchid pollen, acting as pollen wasters. However, Apis mellifera may still contribute to pollination of Diuris where native bees no longer exist. Given the global occurrence of introduced honeybees, we warn that certain orchids may suffer from pollen depletion by these invaders, especially in altered habitats with compromised pollination communities.
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Affiliation(s)
- Daniela Scaccabarozzi
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18 D, 752 36, Uppsala, Sweden.
- School of Molecular and Life Sciences, Curtin University, Perth, Australia.
| | - Lorenzo Guzzetti
- ZooPlantLab, Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Emiliano Pioltelli
- ZooPlantLab, Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Mark Brundrett
- School of Biological Sciences, University of Western Australia, Crawley, Australia
| | | | - Giovanni Polverino
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Mario Vallejo-Marin
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18 D, 752 36, Uppsala, Sweden
| | | | - Zong-Xin Ren
- Kunming Institute of Botany, Chinese Academy of Sciences (CAS), Kunming, China
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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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3
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Pyke GH, Ren ZX. Floral nectar production: what cost to a plant? Biol Rev Camb Philos Soc 2023; 98:2078-2090. [PMID: 37461187 DOI: 10.1111/brv.12997] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 05/29/2023] [Accepted: 06/30/2023] [Indexed: 11/07/2023]
Abstract
Floral nectar production is central to plant pollination, and hence to human wellbeing. As floral nectar is essentially a solution in water of various sugars, it is likely a valuable plant resource, especially in terms of energy, with plants experiencing costs/trade-offs associated with its production or absorption and adopting mechanisms to regulate nectar in flowers. Possible costs of nectar production may also influence the evolution of nectar volume, concentration and composition, of pollination syndromes involving floral nectar, and the production of some crops. There has been frequent agreement that costs of floral nectar production are significant, but relevant evidence is scant and difficult to interpret. Convincing direct evidence comes from experimental studies that relate either enhanced nectar sugar production (through repeated nectar removal) to reduced ability to produce seeds, or increased sugar availability (through absorption of additional artificial nectar) to increased seed production. Proportions of available photosynthate allocated by plants to nectar production may also indicate nectar cost. However, such studies are rare, some do not include treatments of all (or almost all) flowers per plant, and all lack quantitative cost-benefit comparisons for nectar production. Additional circumstantial evidence of nectar cost is difficult to interpret and largely equivocal. Future research should repeat direct experimental approaches that relate reduced or enhanced nectar sugar availability for a plant with consequent ability to produce seeds. To avoid confounding effects of inter-flower resource transfer, each plant should experience a single treatment, with treatment of all or almost all flowers per plant. Resource allocation by plants, pathways used for resource transfer, and the locations of resource sources and sinks should also be investigated. Future research should also consider extension of nectar cost into other areas of biology. For example, evolutionary models of nectar production are rare but should be possible if plant fitness gains and costs associated with nectar production are expressed in the same currency, such as energy. It should then be possible to understand observed nectar production for different plant species and pollination syndromes involving floral nectar. In addition, potential economic benefits should be possible to assess if relationships between nectar production and crop value are evaluated.
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Affiliation(s)
- Graham H Pyke
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, 650201, China
- School of Natural Sciences, Macquarie University, Balaclava Rd, North Ryde, 2113, New South Wales, Australia
| | - Zong-Xin Ren
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, 132 Lanhei Road, Kunming, 650201, China
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Lanzino M, Palermo AM, Pellegrino G. Pollination mechanism in Serapias with no pollinaria reconfiguration. AOB PLANTS 2023; 15:plad054. [PMID: 37899971 PMCID: PMC10601389 DOI: 10.1093/aobpla/plad054] [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: 03/02/2023] [Accepted: 08/09/2023] [Indexed: 10/31/2023]
Abstract
Orchidaceae, one of the most numerous families in the world's flora, have evolved various pollination strategies to favour cross-pollination, such as deceptive pollination and pollinarium reconfiguration. Among the terrestrial orchids of the Mediterranean, only species belonging to the genus Serapias show a strategy defined as shelter imitation. The floral elements form a tubular structure that insects use during their resting phases. The purpose of this article was to clarify the mechanisms that guarantee pollination with particular attention to the morphological interactions between orchids and pollinators and whether pollinaria reconfiguration is necessary in the promotion of cross-pollination in Serapias. Breeding system experiments and hand-pollination treatments indicated that Serapias was highly self-compatible, shows low value of natural fruit set and is pollinator limited. Time-lapse photos showed that the pollinarium had no refolding of the stipe or caudicle after its removal from the flower. The morphology of the flower determined the attack of the pollinarium on the occiput/vertex of insect. When the insect left the flower, the pollinarium was unable to encounter the stigma. When the insect made a second visit to another flower, the pollen masses of the first pollinarium ended up on the stigma and at the same time, the insect picked up a second pollinarium. Our observations and analyses suggested that morphological interactions between flower and pollinator are crucial to the success of pollination and to prevent self-pollination and thus that pollinarium reconfiguration is unnecessary in shelter deceptive orchids, such as Serapias species, for the promotion of cross-pollination. Serapias represent a case of interactions between plant and pollinator; the formation of the tubular shape of the flower is an essential preadaptation for the development of resting site mimicry originating exclusively in Serapias among Mediterranean orchids.
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Affiliation(s)
- Micaela Lanzino
- Department of Biology, Ecology and Earth Sciences, University of Calabria, 87036 Rende, Cosenza, Italy
| | - Anna Maria Palermo
- Department of Biology, Ecology and Earth Sciences, University of Calabria, 87036 Rende, Cosenza, Italy
| | - Giuseppe Pellegrino
- Department of Biology, Ecology and Earth Sciences, University of Calabria, 87036 Rende, Cosenza, Italy
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Deng X, Hu C, Xie C, Lu A, Luo Y, Peng T, Huang W. Metabolomic and Transcriptomic Analysis Reveal the Role of Metabolites and Genes in Modulating Flower Color of Paphiopedilum micranthum. PLANTS (BASEL, SWITZERLAND) 2023; 12:2058. [PMID: 37653975 PMCID: PMC10220555 DOI: 10.3390/plants12102058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/16/2023] [Accepted: 05/19/2023] [Indexed: 09/02/2023]
Abstract
Food-deceptive flowers primarily use visual signals (such as color) to mimic model plants and deceive insects into achieving pollination. Paphiopedilum micranthum is a food-deceptive orchid that has a pink labellum and two purple petals with a yellow base and has been proven to be pollinated by bumblebees. However, the chemical and molecular bases of the floral color are not well understood. We conducted targeted metabolite profiling and transcriptomic analysis to determine the color signal and its genetic basis in P. micranthum. We found that both anthocyanins and carotenoids contribute significantly to the formation of floral color that determines the color signal. Higher concentrations of anthocyanins (cyanidin and peonidin) and carotenoids (primarily lutein and zeaxanthin) were detected in the petal compared to the labellum. The upregulation of structural genes of CHS, F3'H, DFR and ANS on the anthocyanin biosynthesis pathway in petals was identified, as well as three genes of LCYE, BCH, and CCD4 on the carotenoid biosynthesis pathway. Furthermore, we discovered that three R2R3-MYBs and one bHLH transcription factors were co-expressed with the expression of different genes. These genes and transcription factors may be responsible for the spatial color difference of P. micranthum. Our study emphasizes that the color of this food-deceptive orchids is achieved through specific genes and transcription factors associated with the pigment biosynthesis pathway.
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Affiliation(s)
- Xinyan Deng
- School of Life Sciences, Guizhou Normal University, Guiyang 550025, China;
- Eastern China Conservation Centre for Wild Endangered Plant Resources, Shanghai Chenshan Botanical Garden, Shanghai 201602, China; (C.H.); (C.X.); (A.L.)
| | - Chao Hu
- Eastern China Conservation Centre for Wild Endangered Plant Resources, Shanghai Chenshan Botanical Garden, Shanghai 201602, China; (C.H.); (C.X.); (A.L.)
| | - Chengzhi Xie
- Eastern China Conservation Centre for Wild Endangered Plant Resources, Shanghai Chenshan Botanical Garden, Shanghai 201602, China; (C.H.); (C.X.); (A.L.)
- College of Forestry, Hainan University, Haikou 570228, China
| | - Aixian Lu
- Eastern China Conservation Centre for Wild Endangered Plant Resources, Shanghai Chenshan Botanical Garden, Shanghai 201602, China; (C.H.); (C.X.); (A.L.)
| | - Yibo Luo
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100000, China
- China National Botanical Garden, Beijing 100000, China
| | - Tao Peng
- School of Life Sciences, Guizhou Normal University, Guiyang 550025, China;
| | - Weichang Huang
- Eastern China Conservation Centre for Wild Endangered Plant Resources, Shanghai Chenshan Botanical Garden, Shanghai 201602, China; (C.H.); (C.X.); (A.L.)
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Scaccabarozzi D, Lunau K, Guzzetti L, Cozzolino S, Dyer AG, Tommasi N, Biella P, Galimberti A, Labra M, Bruni I, Pattarini G, Brundrett M, Gagliano M. Mimicking orchids lure bees from afar with exaggerated ultraviolet signals. Ecol Evol 2023; 13:e9759. [PMID: 36726874 PMCID: PMC9884568 DOI: 10.1002/ece3.9759] [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: 08/27/2022] [Revised: 12/22/2022] [Accepted: 01/04/2023] [Indexed: 02/03/2023] Open
Abstract
Flowers have many traits to appeal to pollinators, including ultraviolet (UV) absorbing markings, which are well-known for attracting bees at close proximity (e.g., <1 m). While striking UV signals have been thought to attract pollinators also from far away, if these signals impact the plant pollinia removal over distance remains unknown. Here, we report the case of the Australian orchid Diuris brumalis, a nonrewarding species, pollinated by bees via mimicry of the rewarding pea plant Daviesia decurrens. When distant from the pea plant, Diuris was hypothesized to enhance pollinator attraction by exaggeratedly mimicking the floral ultraviolet (UV) reflecting patterns of its model. By experimentally modulating floral UV reflectance with a UV screening solution, we quantified the orchid pollinia removal at a variable distance from the model pea plants. We demonstrate that the deceptive orchid Diuris attracts bee pollinators by emphasizing the visual stimuli, which mimic the floral UV signaling of the rewarding model Daviesia. Moreover, the exaggerated UV reflectance of Diuris flowers impacted pollinators' visitation at an optimal distance from Da. decurrens, and the effect decreased when orchids were too close or too far away from the model. Our findings support the hypothesis that salient UV flower signaling plays a functional role in visual floral mimicry, likely exploiting perceptual gaps in bee neural coding, and mediates the plant pollinia removal at much greater spatial scales than previously expected. The ruse works most effectively at an optimal distance of several meters revealing the importance of salient visual stimuli when mimicry is imperfect.
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Affiliation(s)
- Daniela Scaccabarozzi
- School of Pharmaceutical Science and TechnologyTianjin UniversityTianjinChina
- School of Molecular and Life SciencesCurtin UniversityBentleyWestern AustraliaAustralia
| | - Klaus Lunau
- Institute of Sensory EcologyHeinrich‐Heine University DüsseldorfDüsseldorfGermany
| | - Lorenzo Guzzetti
- ZooPlantLab, Dipartimento di Biotecnologie e BioscienzeUniversity of Milano – BicoccaMilanItaly
| | | | - Adrian G. Dyer
- Bio‐Inspired Digital Sensing Lab, School of Media and CommunicationRMIT UniversityMelbourneVictoriaAustralia
- Department of Physiology and Neuroscience Program, Biomedicine Discovery InstituteMonash UniversityClaytonVictoriaAustralia
| | - Nicola Tommasi
- ZooPlantLab, Dipartimento di Biotecnologie e BioscienzeUniversity of Milano – BicoccaMilanItaly
| | - Paolo Biella
- ZooPlantLab, Dipartimento di Biotecnologie e BioscienzeUniversity of Milano – BicoccaMilanItaly
| | - Andrea Galimberti
- ZooPlantLab, Dipartimento di Biotecnologie e BioscienzeUniversity of Milano – BicoccaMilanItaly
| | - Massimo Labra
- ZooPlantLab, Dipartimento di Biotecnologie e BioscienzeUniversity of Milano – BicoccaMilanItaly
| | - Ilaria Bruni
- ZooPlantLab, Dipartimento di Biotecnologie e BioscienzeUniversity of Milano – BicoccaMilanItaly
| | - Giorgio Pattarini
- Department of Mathematics and PhysicsUniversity of StavangerStavangerNorway
| | - Mark Brundrett
- School of Biological SciencesUniversity of Western AustraliaPerthWestern AustraliaAustralia
| | - Monica Gagliano
- Biological Intelligence (BI) Lab, Faculty of Sciences & EngineeringSouthern Cross UniversityLismoreNew South WalesAustralia
- Sydney Environment Institute (SEI)The University of SydneyCamperdownNew South WalesAustralia
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Large-Scale In Vitro Multiplication and Phytochemical Analysis of Himantoglossum affine (Boiss.) Schltr.: An Endangered Euro-Mediterranean Terrestrial Orchid. DIVERSITY 2022. [DOI: 10.3390/d14121137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Himantoglossum affine is a threatened terrestrial orchid. We aimed to optimize asymbiotic seed germination and direct embryogenesis and to analyze the phytochemical profile and physico-biochemical analysis of leaf and tuber. The individual use of organic nitrogen compounds resulted in higher germination efficiencies, while the shortest times to germination were observed using coconut water plus casein hydrolysate. Plantlets grown on media supplemented with pineapple juice and peptone had the highest plantlet length and weight. For embryogenesis, the highest regeneration rate (44%) and embryo number/explant (10.12 ± 2.08) were observed in young protocorm-like body (PLB) explants with 0.5 mg/L naphthalene acetic acid (NAA) and 1 mg/L thidiazuron (TDZ). During the acclimatization process, the scattered vascular tubes converted to fully developed vascular tissues, ensuring maximum sap flux. Gas chromatography–mass spectrometry analysis identified 1,2,3-propanetriol, monoacetate, 4H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl, and 2-butenedioic acid, 2-methyl-, (E)- as the most prevalent compounds. We reported higher contents of total phenolics and flavonoids and antioxidant activity compared to other terrestrial orchids. The glucomannan content (36.96%) was also higher than starch content (31.31%), comparable to those reported in other tuberous orchids. Based on the fragmentation of H. affine populations in the Middle East and Euro-Mediterranean countries due to over-harvesting, climate change, and/or human impact, our procedure offers a tool for the re-introduction of in vitro-raised plants to threatened areas.
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Han ZD, Wu Y, Bernhardt P, Wang H, Ren ZX. Observations on the pollination and breeding systems of two Corybas species (Diurideae; Orchidaceae) by fungus gnats (Mycetophilidae) in southwestern Yunnan, China. BMC PLANT BIOLOGY 2022; 22:426. [PMID: 36050636 PMCID: PMC9438300 DOI: 10.1186/s12870-022-03816-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 08/26/2022] [Indexed: 06/15/2023]
Abstract
Modes of floral presentation in some angiosperms attract flies that eat and/or oviposit on seasonal fruiting bodies of fungi. Mushroom mimesis by orchid flowers has been speculated in the geoflorous, Indo-Malaysian-Australasian, genus Corybas s.l. for decades but most studies remain fragmentary and are often inconclusive. Here we report the roles of fungus gnats as pollinators of Corybas geminigibbus and C. shanlinshiensis in southwestern Yunnan, China, combining results of field observations, lab analyses, and manipulative experiments. Hand pollination experiments suggested both species were self-compatible but incapable of mechanical self-pollination, thereby requiring pollinators for fruit production. A female of a Phthinia sp. (Mycetophilidae) carried a pollinarium of C. geminigibbus dorsally on its thorax. Two females and one male of Exechia sp. (Mycetophilidae) visiting flowers of C. shanlinshiensis carried dorsal depositions of pollinaria on their thoraces. Mycetophilid eggs were not found in the flowers of either species. The comparative fragrance analyses of these flowers and three co-fruiting mushroom species did not suggest that either orchid species was a brood-site mimic. This is the first confirmation of the dispersal of pollinaria of Corybas species by fungus gnats in subtropical-temperate Asia.
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Affiliation(s)
- Zhou-Dong Han
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
- University of Chinese Academy of Sciences, Beijing, China
| | - You Wu
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
- University of Chinese Academy of Sciences, Beijing, China
| | | | - Hong Wang
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
- University of Chinese Academy of Sciences, Beijing, China.
- Lijiang Forest Biodiversity National Observation and Research Station, Lijiang, China.
| | - Zong-Xin Ren
- CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China.
- University of Chinese Academy of Sciences, Beijing, China.
- Lijiang Forest Biodiversity National Observation and Research Station, Lijiang, China.
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Are some species ‘robust’ to exploitation? Explaining persistence in deceptive relationships. Evol Ecol 2022. [DOI: 10.1007/s10682-022-10174-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AbstractAnimals and plants trick others in an extraordinary diversity of ways to gain fitness benefits. Mimicry and deception can, for example, lure prey, reduce the costs of parental care or aid in pollination–in ways that impose fitness costs on the exploited party. The evolutionary maintenance of such asymmetric relationships often relies on these costs being mitigated through counter-adaptations, low encounter rates, or indirect fitness benefits. However, these mechanisms do not always explain the evolutionary persistence of some classic deceptive interactions.Sexually deceptive pollination (in which plants trick male pollinators into mating with their flowers) has evolved multiple times independently, mainly in the southern hemisphere and especially in Australasia and Central and South America. This trickery imposes considerable costs on the males: they miss out on mating opportunities, and in some cases, waste their limited sperm on the flower. These relationships appear stable, yet in some cases there is little evidence suggesting that their persistence relies on counter-adaptations, low encounter rates, or indirect fitness benefits. So, how might these relationships persist?Here, we introduce and explore an additional hypothesis from systems biology: that some species are robust to exploitation. Robustness arises from a species’ innate traits and means they are robust against costs of exploitation. This allows species to persist where a population without those traits would not, making them ideal candidates for exploitation. We propose that this mechanism may help inform new research approaches and provide insight into how exploited species might persist.
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Orchidaceae-Derived Anticancer Agents: A Review. Cancers (Basel) 2022; 14:cancers14030754. [PMID: 35159021 PMCID: PMC8833831 DOI: 10.3390/cancers14030754] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/28/2022] [Accepted: 01/28/2022] [Indexed: 02/06/2023] Open
Abstract
Simple Summary Orchids are commonly used in folk medicine for the treatment of infections and tumors but little is known about the actual chemical composition of these plants and their anticancer properties. In this paper, the most recent literature on orchid-derived bioactive substances with anticancer properties is reviewed. According to the published data, numerous species of orchids contain potential antitumor chemicals. Still, a relatively insignificant number of species of orchids have been tested for their bioactive properties and most of those studies were on Asian taxa. Broader research, ’including American and African species, as well as the correct identification of samples, is essential for evaluating the usefulness of orchids as a plant family with huge anticancer potential. Abstract Species of orchids, which belong to the largest family of flowering plants, are commonly used in folk medicine for the treatment of infections and tumors. However, little is known about the actual chemical composition of these plants and their anticancer properties. In this paper, the most recent literature on orchid-derived bioactive substances with anticancer properties is reviewed. For the assessment, previous papers on the anticancer activity of Orchidaceae published since 2015 were considered. The papers were found by exploring electronic databases. According to the available data, many species of orchids contain potential antitumor chemicals. The bioactive substances in a relatively insignificant number of orchids are identified, and most studies are on Asian taxa. Broader research on American and African species and the correct identification of samples included in the experiments are essential for evaluating the usefulness of orchids as a plant family with vast anticancer potential.
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Zheng CC, Luo YB, Jiao RF, Gao XF, Xu B. Cypripedium lichiangense (Orchidaceae) mimics a humus-rich oviposition site to attract its female pollinator, Ferdinandea cuprea (Syrphidae). PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:145-156. [PMID: 34490731 DOI: 10.1111/plb.13336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
Most species in the genus Cypripedium (Cypripedioideae) produce trap flowers, making it a model lineage to study deceptive pollination. Floral attractants in most species studied appear to target bee species of different sizes. However, more recent publications report fly pollination in some subalpine species, suggesting novel suites of adaptive floral traits. Cypripedium lichiangense (section Trigonopedia) is an endangered subalpine species endemic to the Hengduan Mountains, China. We observed and analysed its floral traits, pollinators and breeding systems over 2 years in situ and in the lab. Cypripedium lichiangense was visited by females of Ferdinandea cuprea (Syrphidae). The pollinia were carried dorsally on the fly thoraces. The eggs of this fly were frequently found in the saccate labellum and on other floral organs, suggesting brood-site mimesis. The orchid is self-compatible, but cross-pollination produces more viable embryos. We propose a new mode of floral mimesis, humus-rich oviposition site mimicry, for C. lichiangense. Compared with the mimesis of aphid colonies attracting syrphid pollinators (subfamily Syrphinae), whose larvae are entomophagic, as reported in some Paphiopedilum species (Cypripedioideae), pollination by deceit in C. lichiangense represents a distinct and separate mode of exploitation of another saprophagic (or phytophagic) larvae syrphid lineage in the subfamily Eristalinae and appears to indicate diversity of pollination strategies in Section Trigonopedia of Cypripedium. However, this new brood-site mimesis seems to be less attractive to pollinators. As a possible adaptation to the weak attracted pollination strategy, this plant species has a long flowering period and extended lifespan of individual flowers to ensure reproductive success.
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Affiliation(s)
- C C Zheng
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Y B Luo
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - R F Jiao
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- Key Laboratory of Bio-Resources and Eco-Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - X F Gao
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- University of Chinese Academy of Sciences, Beijing, China
| | - B Xu
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China
- University of Chinese Academy of Sciences, Beijing, China
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Watteyn C, Scaccabarozzi D, Muys B, Van Der Schueren N, Van Meerbeek K, Guizar Amador MF, Ackerman JD, Cedeño Fonseca MV, Chinchilla Alvarado IF, Reubens B, Pillco Huarcaya R, Cozzolino S, Karremans AP. Trick or treat? Pollinator attraction in
Vanilla pompona
(Orchidaceae). Biotropica 2021. [DOI: 10.1111/btp.13034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Charlotte Watteyn
- Division of Forest, Nature and Landscape Department Earth and Environmental Sciences KU Leuven Heverlee Belgium
- Lankester Botanical Garden University of Costa Rica Cartago Costa Rica
| | - Daniela Scaccabarozzi
- School of Molecular and Life Sciences Curtin University Perth WA Australia
- Department of Biology University of Naples Federico IICorso Umberto I Naples Italy
| | - Bart Muys
- Division of Forest, Nature and Landscape Department Earth and Environmental Sciences KU Leuven Heverlee Belgium
| | - Nele Van Der Schueren
- Division of Forest, Nature and Landscape Department Earth and Environmental Sciences KU Leuven Heverlee Belgium
| | - Koenraad Van Meerbeek
- Division of Forest, Nature and Landscape Department Earth and Environmental Sciences KU Leuven Heverlee Belgium
| | - Maria F. Guizar Amador
- Department of Evolution and Ecology University of California, Davis Davis California USA
| | - James D. Ackerman
- Department of Biology University of Puerto Rico San Juan Puerto Rico
| | - Marco V. Cedeño Fonseca
- Lankester Botanical Garden University of Costa Rica Cartago Costa Rica
- Herbario Luis Fournier Origgi Department of Biology University of Costa Rica San José Costa Rica
| | - Isler F. Chinchilla Alvarado
- Lankester Botanical Garden University of Costa Rica Cartago Costa Rica
- Herbario Luis Fournier Origgi Department of Biology University of Costa Rica San José Costa Rica
| | - Bert Reubens
- Plant Sciences Unit Flanders Research Institute for Agriculture, Fisheries and Food Merelbeke Belgium
| | | | - Salvatore Cozzolino
- Department of Biology University of Naples Federico IICorso Umberto I Naples Italy
| | - Adam P. Karremans
- Lankester Botanical Garden University of Costa Rica Cartago Costa Rica
- Naturalis Biodiversity Center Endless Forms Group Leiden University Leiden The Netherlands
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13
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Brzosko E, Mirski P. Floral Nectar Chemistry in Orchids: A Short Review and Meta-Analysis. PLANTS (BASEL, SWITZERLAND) 2021; 10:2315. [PMID: 34834677 PMCID: PMC8620889 DOI: 10.3390/plants10112315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/21/2021] [Accepted: 10/23/2021] [Indexed: 05/12/2023]
Abstract
Nectar is one of the most important flower traits, shaping plant-pollinator interactions and reproductive success. Despite Orchidaceae including numerous nectariferous species, nectar chemistry in this family has been infrequently studied. Therefore, the aim of this study is to compile data about nectar attributes in different orchid species. The scarcity of data restricted analyses to sugar concentration and composition. Our results suggest that the most important factor shaping nectar traits in orchids is the pollinator type, although we also found differentiation of nectar traits according to geographical regions. In spurred orchids, the length of the spur impacted nectar traits. We recommend the development of studies on nectar chemistry in orchids, including a wider range of species (both in taxonomic and geographical contexts), as well as extending the analyses to other nectar components (such as amino acids and secondary metabolites). The nectar biome would be also worth investigating, since it could affect the chemical composition of nectar. This will enrich the understanding of the mechanisms of plants-pollinators interactions.
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Affiliation(s)
- Emilia Brzosko
- Faculty of Biology, University of Bialystok, Ciołkowskiego 1J, 15-245 Bialystok, Poland
| | - Paweł Mirski
- Faculty of Biology, University of Bialystok, Ciołkowskiego 1J, 15-245 Bialystok, Poland
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14
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Martel C, Rakosy D, Dötterl S, Johnson SD, Ayasse M, Paulus HF, Nilsson LA, Mejlon H, Jersáková J. Specialization for Tachinid Fly Pollination in the Phenologically Divergent Varieties of the Orchid Neotinea ustulata. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.659176] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Despite increased focus on elucidating the various reproductive strategies employed by orchids, we still have only a rather limited understanding of deceptive pollination systems that are not bee- or wasp-mediated. In Europe, the orchid Neotinea ustulata has been known to consist of two phenologically divergent varieties, neither of which provide rewards to its pollinators. However, detailed studies of their reproductive biology have been lacking. Our study aimed to characterize and understand the floral traits (i.e., morphology, color, and scent chemistry) and reproductive biology of N. ustulata. We found that the two varieties differ in all their floral traits; furthermore, while Neotinea ustulata var. ustulata appears to be pollinated by both bees (e.g., Anthophora, Bombus) and flies (e.g., Dilophus, Tachina), var. aestivalis is pollinated almost entirely by flies (i.e., Nowickia, Tachina). Tachinids were also found to be much more effective than bees in removing pollinaria, and we show experimentally that they use the characteristic dark inflorescence top as a cue for approaching inflorescences. Our results thus suggest that while both N. ustulata varieties rely on tachinids for pollination, they differ in their degree of specialization. Further studies are, however, needed to fully understand the reproductive strategy of N. ustulata varieties.
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15
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Luo H, Xiao H, Liang Y, Liu N, Turner C, Tan S, Chen X, Xiong D, Yang B. Batesian mimicry in the nonrewarding saprophytic orchid Danxiaorchis yangii. Ecol Evol 2021; 11:2524-2534. [PMID: 33767819 PMCID: PMC7981215 DOI: 10.1002/ece3.7193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 11/17/2020] [Accepted: 12/21/2020] [Indexed: 11/08/2022] Open
Abstract
Batesian mimicry, a type of deceptive pollination, is a complicated strategy used by nonrewarding plants to attract pollinators, but some hypotheses concerning this have not been systematically verified. In order to show in detail a case of Batesian mimicry on saprophytic orchid Danxiaorchis yangii, the ecological relationship between Danxiaorchis yangii, Lysimachia alfredi and Dufourea spp. was explored. Lysimachia alfredi could provide a reward to Dufourea sp., whereas Danxiaorchis yangii not. The floral morphology and geographical distribution of these two plants were highly overlapping, and the fruit set rate of Danxiaorchis yangii was significantly positively correlated with the number of nearby L. alfredi individuals. In a glass cylinder experiment, Danxiaorchis yangii and L. alfredi attracted Dufourea spp. through visual signals, but the insect could not distinguish between flowers of the two plants before landing on flowers. The ultraviolet reflection spectra of flowers between the two plant species were highly similar. In the hexagonal color models constructed according to the visual characteristics of bees, the flower color signals of these two plant species highly overlap, indicating that the visual signals of the flowers of the two plants to the pollinator were greatly similar. All of these results provided evidence that Danxiaorchis yangii simulated the visual signals of L. alfredi through Batesian mimicry, thereby deceptively attracting Dufourea spp.
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Affiliation(s)
- Huolin Luo
- Jiangxi Key Laboratory of Plant ResourcesSchool of Life ScienceNanchang UniversityNanchangChina
| | - Hanwen Xiao
- Jiangxi Key Laboratory of Plant ResourcesSchool of Life ScienceNanchang UniversityNanchangChina
| | - Yuelong Liang
- Jiangxi Jiulianshan National Nature ReserveGanzhouChina
| | - Nannan Liu
- Jiangxi Key Laboratory of Plant ResourcesSchool of Life ScienceNanchang UniversityNanchangChina
| | - Cassidy Turner
- College of Health SolutionsArizona State UniversityScottsdaleAZUSA
| | - Shaolin Tan
- Jiangxi Key Laboratory of Plant ResourcesSchool of Life ScienceNanchang UniversityNanchangChina
| | - Xinghui Chen
- Jiangxi Key Laboratory of Plant ResourcesSchool of Life ScienceNanchang UniversityNanchangChina
| | - Dongjin Xiong
- Jiangxi Key Laboratory of Plant ResourcesSchool of Life ScienceNanchang UniversityNanchangChina
| | - Boyun Yang
- Jiangxi Key Laboratory of Plant ResourcesSchool of Life ScienceNanchang UniversityNanchangChina
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16
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Basist G, Dyer AG, Garcia JE, Raleigh RE, Lawrie AC. Why Variation in Flower Color May Help Reproductive Success in the Endangered Australian Orchid Caladenia fulva. FRONTIERS IN PLANT SCIENCE 2021; 12:599874. [PMID: 33633758 PMCID: PMC7899986 DOI: 10.3389/fpls.2021.599874] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 01/15/2021] [Indexed: 05/27/2023]
Abstract
Caladenia fulva G.W. Carr (Tawny Spider-orchid) is a terrestrial Australian endangered orchid confined to contiguous reserves in open woodland in Victoria, Australia. Natural recruitment is poor and no confirmed pollinator has been observed in the last 30 years. Polymorphic variation in flower color complicates plans for artificial pollination, seed collection and ex situ propagation for augmentation or re-introduction. DNA sequencing showed that there was no distinction among color variants in the nuclear ribosomal internal transcribed spacer (ITS) region and the chloroplast trnT-trnF and matK regions. Also, authentic specimens of both C. fulva and Caladenia reticulata from the reserves clustered along with these variants, suggesting free interbreeding. Artificial cross-pollination in situ and assessment of seed viability further suggested that no fertility barriers existed among color variants. Natural fruit set was 15% of the population and was proportional to numbers of the different flower colors but varied with orchid patch within the population. Color modeling on spectral data suggested that a hymenopteran pollinator could discriminate visually among color variants. The similarity in fruiting success, however, suggests that flower color polymorphism may avoid pollinator habituation to specific non-rewarding flower colors. The retention of large brightly colored flowers suggests that C. fulva has maintained attractiveness to foraging insects rather than evolving to match a scarce unreliable hymenopteran sexual pollinator. These results suggest that C. fulva should be recognized as encompassing plants with these multiple flower colors, and artificial pollination should use all variants to conserve the biodiversity of the extant population.
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Affiliation(s)
- Georgia Basist
- School of Science, RMIT University, Bundoora, VIC, Australia
| | - Adrian G. Dyer
- Bio-inspired Digital Sensing Lab, School of Media and Communication, RMIT University, Melbourne, VIC, Australia
- Department of Physiology, Monash University, Melbourne, VIC, Australia
| | - Jair E. Garcia
- Bio-inspired Digital Sensing Lab, School of Media and Communication, RMIT University, Melbourne, VIC, Australia
| | - Ruth E. Raleigh
- School of Science, RMIT University, Bundoora, VIC, Australia
- Royal Botanic Gardens Melbourne, South Yarra, VIC, Australia
| | - Ann C. Lawrie
- School of Science, RMIT University, Bundoora, VIC, Australia
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17
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Capó M, Borràs J, Perelló-Suau S, Rita J, Cursach J. Ecological factors affecting the fitness of the threatened orchid Anacamptis robusta (Orchidaceae): Habitat disturbance, interactions with a co-flowering rewarding orchid and hybridization events. PLANT BIOLOGY (STUTTGART, GERMANY) 2021; 23:121-129. [PMID: 32896978 DOI: 10.1111/plb.13179] [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: 07/16/2020] [Accepted: 08/24/2020] [Indexed: 06/11/2023]
Abstract
The food-deceptive species Anacamptis robusta is threatened in the Balearic Islands, and its habitat has recently been transformed through human disturbance. This study investigated how human disturbance affects the reproductive output of A. robusta and how its fitness is affected by competition with rewarding relatives, fungal infections and hybridization processes. To evaluate the impact of habitat loss on plant fitness, data on reproductive measures were obtained in two well-conserved subpopulations and the unique disturbed subpopulation. Photo-trapping cameras were installed to determine the floral visitation rate. All flowering individuals in 2019 were georeferenced using differential GPS to examine the influence of geospatial patterns on the reproductive success of A. robusta. In addition, hand-pollination treatments were performed to evaluate the hybridization between A. coriophora and A. robusta and the origin of A. × albuferensis. The human-disturbed subpopulation of A. robusta had a lower fruit set success than the subpopulations in well-conserved areas. The presence of A. coriophora is negatively affecting the reproductive output of A. robusta. Moreover, A. robusta can only act as the pollen donor during hybridization. The complexity of the ecological system, which is enhanced by the strong pollinator dependence of the threatened species, must be considered when making conservation decisions. Although human disturbance directly affects plant population stability, other ecological issues must be considered, such as pollinator interaction, interspecific competition for pollinators, fungal infection and hybridization events.
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Affiliation(s)
- M Capó
- Laboratory of Botany, Research Group on Plant Biology under Mediterranean Conditions, Department of Biology, University of Balearic Islands, Palma, Spain
| | - J Borràs
- Laboratory of Botany, Research Group on Plant Biology under Mediterranean Conditions, Department of Biology, University of Balearic Islands, Palma, Spain
| | - S Perelló-Suau
- Laboratory of Botany, Research Group on Plant Biology under Mediterranean Conditions, Department of Biology, University of Balearic Islands, Palma, Spain
| | - J Rita
- Laboratory of Botany, Research Group on Plant Biology under Mediterranean Conditions, Department of Biology, University of Balearic Islands, Palma, Spain
| | - J Cursach
- Laboratory of Botany, Research Group on Plant Biology under Mediterranean Conditions, Department of Biology, University of Balearic Islands, Palma, Spain
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18
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Phillips RD, Reiter N, Peakall R. Orchid conservation: from theory to practice. ANNALS OF BOTANY 2020; 126:345-362. [PMID: 32407498 PMCID: PMC7424752 DOI: 10.1093/aob/mcaa093] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 05/07/2020] [Indexed: 05/21/2023]
Abstract
BACKGROUND Given the exceptional diversity of orchids (26 000+ species), improving strategies for the conservation of orchids will benefit a vast number of taxa. Furthermore, with rapidly increasing numbers of endangered orchids and low success rates in orchid conservation translocation programmes worldwide, it is evident that our progress in understanding the biology of orchids is not yet translating into widespread effective conservation. SCOPE We highlight unusual aspects of the reproductive biology of orchids that can have important consequences for conservation programmes, such as specialization of pollination systems, low fruit set but high seed production, and the potential for long-distance seed dispersal. Further, we discuss the importance of their reliance on mycorrhizal fungi for germination, including quantifying the incidence of specialized versus generalized mycorrhizal associations in orchids. In light of leading conservation theory and the biology of orchids, we provide recommendations for improving population management and translocation programmes. CONCLUSIONS Major gains in orchid conservation can be achieved by incorporating knowledge of ecological interactions, for both generalist and specialist species. For example, habitat management can be tailored to maintain pollinator populations and conservation translocation sites selected based on confirmed availability of pollinators. Similarly, use of efficacious mycorrhizal fungi in propagation will increase the value of ex situ collections and likely increase the success of conservation translocations. Given the low genetic differentiation between populations of many orchids, experimental genetic mixing is an option to increase fitness of small populations, although caution is needed where cytotypes or floral ecotypes are present. Combining demographic data and field experiments will provide knowledge to enhance management and translocation success. Finally, high per-fruit fecundity means that orchids offer powerful but overlooked opportunities to propagate plants for experiments aimed at improving conservation outcomes. Given the predictions of ongoing environmental change, experimental approaches also offer effective ways to build more resilient populations.
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Affiliation(s)
- Ryan D Phillips
- Department of Ecology, Environment and Evolution, La Trobe University, Melbourne, Victoria, Australia
- Kings Park Science, Department of Biodiversity Conservation and Attractions, Kings Park, WA, Australia
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
| | - Noushka Reiter
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
- Royal Botanic Gardens Victoria, Corner of Ballarto Road and Botanic Drive, Cranbourne, VIC, Australia
| | - Rod Peakall
- Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, ACT, Australia
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19
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Martel C, Neubig KM, Williams NH, Ayasse M. The uncinate viscidium and floral setae, an evolutionary innovation and exaptation to increase pollination success in the Telipogon alliance (Orchidaceae: Oncidiinae). ORG DIVERS EVOL 2020. [DOI: 10.1007/s13127-020-00457-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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20
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Shrestha M, Garcia JE, Burd M, Dyer AG. Australian native flower colours: Does nectar reward drive bee pollinator flower preferences? PLoS One 2020; 15:e0226469. [PMID: 32525873 PMCID: PMC7289428 DOI: 10.1371/journal.pone.0226469] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 05/18/2020] [Indexed: 11/18/2022] Open
Abstract
Colour is an important signal that flowering plants use to attract insect pollinators like bees. Previous research in Germany has shown that nectar volume is higher for flower colours that are innately preferred by European bees, suggesting an important link between colour signals, bee preferences and floral rewards. In Australia, flower colour signals have evolved in parallel to the Northern hemisphere to enable easy discrimination and detection by the phylogenetically ancient trichromatic visual system of bees, and native Australian bees also possess similar innate colour preferences to European bees. We measured 59 spectral signatures from flowers present at two preserved native habitats in South Eastern Australia and tested whether there were any significant differences in the frequency of flowers presenting higher nectar rewards depending upon the colour category of the flower signals, as perceived by bees. We also tested if there was a significant correlation between chromatic contrast and the frequency of flowers presenting higher nectar rewards. For the entire sample, and for subsets excluding species in the Asteraceae and Orchidaceae, we found no significant difference among colour categories in the frequency of high nectar reward. This suggests that whilst such relationships between flower colour signals and nectar volume rewards have been observed at a field site in Germany, the effect is likely to be specific at a community level rather than a broad general principle that has resulted in the common signalling of bee flower colours around the world.
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Affiliation(s)
- Mani Shrestha
- Bio-Inspired Digital Lab (BIDS-Lab), Schools of Media and Communication, RMIT University, Melbourne, Australia
| | - Jair E. Garcia
- Bio-Inspired Digital Lab (BIDS-Lab), Schools of Media and Communication, RMIT University, Melbourne, Australia
| | - Martin Burd
- School of Biological Sciences, Monash University, Melbourne, Australia
| | - Adrian G. Dyer
- Bio-Inspired Digital Lab (BIDS-Lab), Schools of Media and Communication, RMIT University, Melbourne, Australia
- * E-mail:
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