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Wong DCJ, Perkins J, Peakall R. Conserved pigment pathways underpin the dark insectiform floral structures of sexually deceptive Chiloglottis (Orchidaceae). FRONTIERS IN PLANT SCIENCE 2022; 13:976283. [PMID: 36275580 PMCID: PMC9581149 DOI: 10.3389/fpls.2022.976283] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 08/24/2022] [Indexed: 06/10/2023]
Abstract
Sexually deceptive plants achieve pollination by enticing specific male insects as pollinators using a combination of olfactory, visual, and morphological mimicry. The sexually deceptive orchid genus Chiloglottis is comprised of some 30 species with predominantly dull green-red flowers except for the dark insectiform calli/callus structure from the labellum lamina. This unique structure mimics the female of the pollinator and potentially enhances the visibility of the mimic. However, the chemical and genetic basis for the color of these structures remains poorly understood across the genus. The goal of this study was to investigate the flower color biochemistry and patterns of gene expression across the anthocyanin and flavonol glycoside biosynthetic pathway within the calli structures across the three distinct clades of Chiloglottis (Formicifera, Reflexa, and Valida) using chemical and transcriptome analysis. Our phylogenomic analysis confirmed the close sister relationship between the Reflexa/Formicifera clades and reaffirms the basal position of the Valida clade. Additionally, the biochemical basis of the dark calli/callus structures is conserved across the genus. Nonetheless, the proportion of methoxylated anthocyanin and flavonol glycoside derivatives and the mean gene expression levels appear to differentiate the Reflexa and Formicifera clades from the Valida clade. In future studies, it will be of interest to tease apart the role of phylogeny, environment, pollinators, and other factors as potential drivers of the observed biochemistry and gene expression differences. It will also be important to characterize the function of candidate genes such as DFR, LDOX, and FLS in this fascinating case of flower color mimicry.
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Low SL, Wong SY. The diversification of thecae horns and their putative significance—a case study of Schismatoglottideae (Araceae). ORG DIVERS EVOL 2022. [DOI: 10.1007/s13127-022-00573-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Huang X, Chen M, Wang L, Yang M, Yang N, Li Z, Duan Y. Phenotypic Selection in Halenia elliptica D. Don (Gentianaceae), an Alpine Biennial with Mixed Mating System. PLANTS (BASEL, SWITZERLAND) 2022; 11:1488. [PMID: 35684261 PMCID: PMC9183009 DOI: 10.3390/plants11111488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 05/30/2022] [Accepted: 05/30/2022] [Indexed: 11/16/2022]
Abstract
The transition from outcrossing to selfing is a common evolutionary trend in flowering plants, and floral traits change significantly with the evolution of selfing. Whether or not plant traits are subjected to selection remains an open question in species with mixed mating systems. We examined phenotypic selection in two populations of Halenia elliptica with different selfing rates. We found that the pollen-ovule ratio, seed size, plant height, spur length, and pollinator visitation rate in the population with the higher selfing rate were lower than those in the population with the lower selfing rate. Selfing provides reproductive assurance for populations when pollinator service is low, and the floral traits that are associated with selfing syndrome are evident in populations with a higher selfing rate but are subjected to weak selection in each of the two populations with different selfing rates. Directional selection for an early flowering time indicated that late blooming flowers could experience a risk of seed development in alpine environments, and for large plants, selection indicated that seed production could be limited by the available resources. The floral traits that are associated with pollinator attraction and specialization could be subjected to weak selection at the plant level as selfing evolves, and the selective pressures that are independent of pollinators might not change significantly; highlighting the selective biotic and abiotic pressures that shape the morphological traits of plant species and their independence from the mating system.
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Affiliation(s)
- Xiaojuan Huang
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi’an 710069, China;
- The Germplasm Bank of Wild Species, Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; (M.C.); (L.W.); (N.Y.)
| | - Minyu Chen
- The Germplasm Bank of Wild Species, Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; (M.C.); (L.W.); (N.Y.)
| | - Linlin Wang
- The Germplasm Bank of Wild Species, Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; (M.C.); (L.W.); (N.Y.)
| | - Mingliu Yang
- School of Ecology and Environmental Science, Yunnan University, Kunming 650091, China;
| | - Nacai Yang
- The Germplasm Bank of Wild Species, Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; (M.C.); (L.W.); (N.Y.)
| | - Zhonghu Li
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi’an 710069, China;
| | - Yuanwen Duan
- The Germplasm Bank of Wild Species, Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; (M.C.); (L.W.); (N.Y.)
- Yunnan Lijiang Forest Ecosystem National Observation and Research Station, Kunming Institute of Botany, Chinese Academy of Sciences, Lijiang 674100, China
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Pontes CADS, Domingos-Melo A, Milet-Pinheiro P, Navarro DMDAF, Lima Nadia T, Machado IC. Staminode of Jacaranda rugosa A.H. Gentry (Bignoniaceae) promotes functional specialization by ensuring signaling and mechanical fit to medium-sized bees. ORG DIVERS EVOL 2022. [DOI: 10.1007/s13127-022-00558-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Wong DCJ, Perkins J, Peakall R. Anthocyanin and Flavonol Glycoside Metabolic Pathways Underpin Floral Color Mimicry and Contrast in a Sexually Deceptive Orchid. FRONTIERS IN PLANT SCIENCE 2022; 13:860997. [PMID: 35401591 PMCID: PMC8983864 DOI: 10.3389/fpls.2022.860997] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 02/17/2022] [Indexed: 06/10/2023]
Abstract
Sexually deceptive plants secure pollination by luring specific male insects as pollinators using a combination of olfactory, visual, and morphological mimicry. Flower color is a key component to this attraction, but its chemical and genetic basis remains poorly understood. Chiloglottis trapeziformis is a sexually deceptive orchid which has predominantly dull green-red flowers except for the central black callus projecting from the labellum lamina. The callus mimics the female of the pollinator and the stark color contrast between the black callus and dull green or red lamina is thought to enhance the visibility of the mimic. The goal of this study was to investigate the chemical composition and genetic regulation of temporal and spatial color patterns leading to visual mimicry, by integrating targeted metabolite profiling and transcriptomic analysis. Even at the very young bud stage, high levels of anthocyanins were detected in the dark callus, with peak accumulation by the mature bud stage. In contrast, anthocyanin levels in the lamina peaked as the buds opened and became reddish-green. Coordinated upregulation of multiple genes, including dihydroflavonol reductase and leucoanthocyanidin dioxygenase, and the downregulation of flavonol synthase genes (FLS) in the callus at the very young bud stage underpins the initial high anthocyanin levels. Conversely, within the lamina, upregulated FLS genes promote flavonol glycoside over anthocyanin production, with the downstream upregulation of flavonoid O-methyltransferase genes further contributing to the accumulation of methylated flavonol glycosides, whose levels peaked in the mature bud stage. Finally, the peak anthocyanin content of the reddish-green lamina of the open flower is underpinned by small increases in gene expression levels and/or differential upregulation in the lamina in select anthocyanin genes while FLS patterns showed little change. Differential expression of candidate genes involved in specific transport, vacuolar acidification, and photosynthetic pathways may also assist in maintaining the distinct callus and contrasting lamina color from the earliest bud stage through to the mature flower. Our findings highlight that flower color in this sexually deceptive orchid is achieved by complex tissue-specific coordinated regulation of genes and biochemical pathways across multiple developmental stages.
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Brzosko E, Bajguz A, Burzyńska J, Chmur M. Nectar Chemistry or Flower Morphology-What Is More Important for the Reproductive Success of Generalist Orchid Epipactis palustris in Natural and Anthropogenic Populations? Int J Mol Sci 2021; 22:12164. [PMID: 34830045 PMCID: PMC8618778 DOI: 10.3390/ijms222212164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/06/2021] [Accepted: 11/08/2021] [Indexed: 11/17/2022] Open
Abstract
The aim of this study was to determine the level of reproductive success (RS) in natural and anthropogenic populations of generalist orchid Epipactis palustris and its dependence on flower structure and nectar composition, i.e., amino acids and sugars. We found that both pollinaria removal and female reproductive success were high and similar in all populations, despite differences in flower traits and nectar chemistry. Flower structures were weakly correlated with parameters of RS. Nectar traits were more important in shaping RS; although, we noted differentiated selection on nectar components in distinct populations. Individuals in natural populations produced nectar with a larger amount of sugars and amino acids. The sucrose to (fructose and glucose) ratio in natural populations was close to 1, while in anthropogenic ones, a clear domination of fructose and glucose was noted. Our results indicate that the flower traits and nectar composition of E. palustris reflect its generalist character and meet the requirements of a wide range of pollinators, differing according to body sizes, mouth apparatus, and dietary needs. Simultaneously, differentiation of nectar chemistry suggests a variation of pollinator assemblages in particular populations or domination of their some groups. To our knowledge, a comparison of nectar chemistry between natural and anthropogenic populations of orchids is reported for the first time in this paper.
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Affiliation(s)
- Emilia Brzosko
- Faculty of Biology, University of Bialystok, Ciolkowskiego 1J, 15-245 Bialystok, Poland; (J.B.); (M.C.)
| | - Andrzej Bajguz
- Faculty of Biology, University of Bialystok, Ciolkowskiego 1J, 15-245 Bialystok, Poland; (J.B.); (M.C.)
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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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Takeda K, Kadokawa T, Kawakita A. Slippery flowers as a mechanism of defence against nectar-thieving ants. ANNALS OF BOTANY 2021; 127:231-239. [PMID: 33410906 PMCID: PMC7789111 DOI: 10.1093/aob/mcaa168] [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: 07/09/2020] [Accepted: 09/09/2020] [Indexed: 06/12/2023]
Abstract
BACKGROUND AND AIMS The great diversity of floral characteristics among animal-pollinated plants is commonly understood to be the result of coevolutionary interactions between plants and pollinators. Floral antagonists, such as nectar thieves, also have the potential to exert an influence upon the selection of floral characteristics, but adaptation against floral antagonists has attracted comparatively little attention. We found that the corollas of hornet-pollinated Codonopsis lanceolata (Campanulaceae) and the tepals of bee-pollinated Fritillaria koidzumiana (Liliaceae) are slippery to nectar-thieving ants living in the plant's habitat; because the flowers of both species have exposed nectaries, slippery perianths may function as a defence against nectar-thieving ants. METHODS We conducted a behavioural experiment and observed perianth surface microstructure by scanning electron microscopy to investigate the mechanism of slipperiness. Field experiments were conducted to test whether slippery perianths prevent floral entry by ants, and whether ant presence inside flowers affects pollination. KEY RESULTS Scanning electron microscopy observations indicated that the slippery surfaces were coated with epicuticular wax crystals. The perianths lost their slipperiness when wiped with hexane. Artificial bridging of the slippery surfaces using non-slippery materials allowed ants to enter flowers more frequently. Experimental introduction of live ants to the Codonopsis flowers evicted hornet pollinators and shortened the duration of pollinator visits. However, no statistical differences were found in the fruit or seed sets of flowers with and without ants. CONCLUSIONS Slippery perianths, most probably based on epicuticular wax crystals, prevent floral entry by ants that negatively affect pollinator behaviour. Experimental evidence of floral defence based on slippery surfaces is rare, but such a mode of defence may be widespread amongst flowering plants.
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Affiliation(s)
- Kazuya Takeda
- Center for Ecological Research, Kyoto University, Otsu, Shiga, Japan
| | - Tomoki Kadokawa
- Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo, Kyoto, Japan
| | - Atsushi Kawakita
- The Botanical Gardens, Graduate School of Science, The University of Tokyo, Bunkyo, Tokyo, Japan
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Christopher DA, Mitchell RJ, Karron JD. Pollination intensity and paternity in flowering plants. ANNALS OF BOTANY 2020; 125:1-9. [PMID: 31586397 PMCID: PMC6948204 DOI: 10.1093/aob/mcz159] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 09/06/2019] [Accepted: 10/01/2019] [Indexed: 05/10/2023]
Abstract
BACKGROUND Siring success plays a key role in plant evolution and reproductive ecology, and variation among individuals creates an opportunity for selection to act. Differences in male reproductive success can be caused by processes that occur during two stages, the pollination and post-pollination phases of reproduction. In the pollination phase, heritable variation in floral traits and floral display affect pollinator visitation patterns, which in turn affect variation among plants in the amount of pollen exported and deposited on recipient stigmas. In the post-pollination phase, differences among individuals in pollen grain germination success and pollen tube growth may cause realized paternity to differ from patterns of pollen receipt. The maternal plant can also preferentially provision some developing seeds or fruits to further alter variation in siring success. SCOPE In this review, we describe studies that advance our understanding of the dynamics of the pollination and post-pollination phases, focusing on how variation in male fitness changes in response to pollen limitation. We then explore the interplay between pollination and post-pollination success, and how these processes respond to ecological factors such as pollination intensity. We also identify pressing questions at the intersection of pollination and paternity and describe novel experimental approaches to elucidate the relative importance of pollination and post-pollination factors in determining male reproductive success. CONCLUSIONS The relative contribution of pollination and post-pollination processes to variation in male reproductive success may not be constant, but rather may vary with pollination intensity. Studies that quantify the effects of pollination and post-pollination phases in concert will be especially valuable as they will enable researchers to more fully understand the ecological conditions influencing male reproductive success.
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Affiliation(s)
- Dorothy A Christopher
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | | | - Jeffrey D Karron
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
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Diversity of Floral Glands and Their Secretions in Pollinator Attraction. REFERENCE SERIES IN PHYTOCHEMISTRY 2020. [DOI: 10.1007/978-3-319-96397-6_48] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Wong DCJ, Amarasinghe R, Falara V, Pichersky E, Peakall R. Duplication and selection in β-ketoacyl-ACP synthase gene lineages in the sexually deceptive Chiloglottis (Orchidaceace). ANNALS OF BOTANY 2019; 123:1053-1066. [PMID: 30789664 PMCID: PMC6589519 DOI: 10.1093/aob/mcz013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Accepted: 02/05/2019] [Indexed: 05/17/2023]
Abstract
BACKGROUND AND AIMS The processes of gene duplication, followed by divergence and selection, probably underpin the evolution of floral volatiles crucial to plant-insect interactions. The Australian sexually deceptive Chiloglottis orchids use a class of 2,5-dialkylcyclohexan-1,3-dione volatiles or 'chiloglottones' to attract specific male wasp pollinators. Here, we explore the expression and evolution of fatty acid pathway genes implicated in chiloglottone biosynthesis. METHODS Both Chiloglottis seminuda and C. trapeziformis produce chiloglottone 1, but only the phylogenetically distinct C. seminuda produces this volatile from both the labellum callus and glandular sepal tips. Transcriptome sequencing and tissue-specific contrasts of the active and non-active floral tissues was performed. The effects of the fatty acid synthase inhibitor cerulenin on chiloglottone production were tested. Patterns of selection and gene evolution were investigated for fatty acid pathway genes. KEY RESULTS Tissue-specific differential expression of fatty acid pathway transcripts was evident between active and non-active floral tissues. Cerulenin significantly inhibits chiloglottone 1 production in the active tissues of C. seminuda. Phylogenetic analysis of plant β-ketoacyl synthase I (KASI), a protein involved in fatty acid biosynthesis, revealed two distinct clades, one of which is unique to the Orchidaceae (KASI-2B). Selection analysis indicated a strong signal of positive selection at the split of KASI-2B followed by relaxed purifying selection in the Chiloglottis clade. CONCLUSIONS By capitalizing on a phylogenetically distinct Chiloglottis from earlier studies, we show that the transcriptional and biochemical dynamics linked to chiloglottone biosynthesis in active tissues are conserved across Chiloglottis. A combination of tissue-specific expression and relaxed purifying selection operating at specific fatty acid pathway genes may hold the key to the evolution of chiloglottones.
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Affiliation(s)
- Darren C J Wong
- Ecology and Evolution, Research School of Biology, The Australian National University, Acton, Australia
- For correspondence. E-mail ,
| | - Ranamalie Amarasinghe
- Ecology and Evolution, Research School of Biology, The Australian National University, Acton, Australia
| | - Vasiliki Falara
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Eran Pichersky
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Rod Peakall
- Ecology and Evolution, Research School of Biology, The Australian National University, Acton, Australia
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Minnaar C, Anderson B, de Jager ML, Karron JD. Plant-pollinator interactions along the pathway to paternity. ANNALS OF BOTANY 2019; 123:225-245. [PMID: 30535041 PMCID: PMC6344347 DOI: 10.1093/aob/mcy167] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 11/23/2018] [Indexed: 05/09/2023]
Abstract
Background The male fitness pathway, from pollen production to ovule fertilization, is thought to strongly influence reproductive trait evolution in animal-pollinated plants. This pathway is characterized by multiple avenues of pollen loss which may lead to reductions in male fitness. However, empirical data on the mechanistic processes leading to pollen loss during transport are limited, and we therefore lack a comprehensive understanding of how male fitness is influenced by each step in the pollination process. Scope This review assesses the history of studying male function in plants and identifies critical gaps in our understanding of the ecology and evolution of pollen transport. We explore male reproductive function along the steps of the pathway to paternity and discuss evolutionary options to overcome barriers to siring success. In particular, we present a newly emerging idea that bodies of pollinators function as a dynamic arena facilitating intense male-male competition, where pollen of rival males is constantly covered or displaced by competitors. This perspective extends the pollen-competitive arena beyond the confines of the stigma and style, and highlights the opportunity for important new breakthroughs in the study of male reproductive strategies and floral evolution.
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Affiliation(s)
- Corneile Minnaar
- Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Bruce Anderson
- Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Marinus L de Jager
- Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa
| | - Jeffrey D Karron
- Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
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Scaccabarozzi D, Cozzolino S, Guzzetti L, Galimberti A, Milne L, Dixon KW, Phillips RD. Masquerading as pea plants: behavioural and morphological evidence for mimicry of multiple models in an Australian orchid. ANNALS OF BOTANY 2018; 122:1061-1073. [PMID: 30184161 PMCID: PMC6266105 DOI: 10.1093/aob/mcy166] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/12/2018] [Indexed: 05/03/2023]
Abstract
Background and Aims While there is increasing recognition of Batesian floral mimicry in plants, there are few confirmed cases where mimicry involves more than one model species. Here, we test for pollination by mimicry in Diuris (Orchidaceae), a genus hypothesized to attract pollinators via mimicry of a range of co-occurring pea plants (Faboideae). Methods Observations of pollinator behaviour were made for Diuris brumalis using arrays of orchid flowers. An analysis of floral traits in the co-flowering community and spectral reflectance measurements were undertaken to test if Di. brumalis and the pea plants showed strong similarity and were likely to be perceived as the same by bees. Pollen removal and fruit-set were recorded at 18 sites over two years to test if fitness of Di. brumalis increased with the abundance of the model species. Key Results Diuris brumalis shares the pollinator species Trichococolletes capillosus and T. leucogenys (Hymenoptera: Colletidae) with co-flowering Faboideae from the genus Daviesia. On Di. brumalis, Trichocolletes exhibited the same stereotyped food-foraging and mate-patrolling behaviour that they exhibit on Daviesia. Diuris and pea plants showed strong morphological similarity compared to the co-flowering plant community, while the spectral reflectance of Diuris was similar to that of Daviesia spp. Fruit-set and pollen removal of Di. brumalis was highest at sites with a greater number of Daviesia flowers. Conclusions Diuris brumalis is pollinated by mimicry of co-occurring congeneric Faboideae species. Evidence for mimicry of multiple models, all of which share pollinator species, suggests that this may represent a guild mimicry system. Interestingly, Di. brumalis belongs to a complex of species with similar floral traits, suggesting that this represents a useful system for investigating speciation in lineages that employ mimicry of food plants.
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Affiliation(s)
- Daniela Scaccabarozzi
- Department of Environment and Agriculture, Curtin University, Bentley, WA, Australia
- Department of Biology, University of Naples Federico II, Complesso Universitario MSA, Naples, Italy
- Kings Park and Botanic Garden, The Botanic Garden and Parks Authority, West Perth, WA, Australia
| | - Salvatore Cozzolino
- Department of Biology, University of Naples Federico II, Complesso Universitario MSA, Naples, Italy
| | - Lorenzo Guzzetti
- Università degli Studi di Milano-Bicocca, ZooPlantLab, Dipartimento di Biotecnologie e Bioscienze, Piazza della Scienza, Milano, Italy
| | - Andrea Galimberti
- Università degli Studi di Milano-Bicocca, ZooPlantLab, Dipartimento di Biotecnologie e Bioscienze, Piazza della Scienza, Milano, Italy
| | - Lynne Milne
- School of Earth and Planetary Sciences, Curtin University, Bentley, WA, Australia
| | - Kingsley W Dixon
- Department of Environment and Agriculture, Curtin University, Bentley, WA, Australia
| | - Ryan D Phillips
- Kings Park and Botanic Garden, The Botanic Garden and Parks Authority, West Perth, WA, Australia
- Evolution, Ecology and Genetics, Research School of Biology, The Australian National University, Canberra, ACT, Australia
- Department of Ecology, Environment and Evolution, La Trobe University, Vic., Australia
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