1
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Moore CD, Farman DI, Särkinen T, Stevenson PC, Vallejo-Marín M. Floral scent changes in response to pollen removal are rare in buzz-pollinated Solanum. PLANTA 2024; 260:15. [PMID: 38829528 PMCID: PMC11147924 DOI: 10.1007/s00425-024-04403-4] [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: 11/26/2023] [Accepted: 03/30/2024] [Indexed: 06/05/2024]
Abstract
MAIN CONCLUSION One of seven Solanum taxa studied displayed associations between pollen presence and floral scent composition and volume, suggesting buzz-pollinated plants rarely use scent as an honest cue for foraging pollinators. Floral scent influences the recruitment, learning, and behaviour of floral visitors. Variation in floral scent can provide information on the amount of reward available or whether a flower has been visited recently and may be particularly important in species with visually concealed rewards. In many buzz-pollinated flowers, tubular anthers opening via small apical pores (poricidal anthers) visually conceal pollen and appear similar regardless of pollen quantity within the anther. We investigated whether pollen removal changes floral scent composition and emission rate in seven taxa of buzz-pollinated Solanum (Solanaceae). We found that pollen removal reduced both the overall emission of floral scent and the emission of specific compounds (linalool and farnesol) in S. lumholtzianum. Our findings suggest that in six out of seven buzz-pollinated taxa studied here, floral scent could not be used as a signal by visitors as it does not contain information on pollen availability.
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Affiliation(s)
- C Douglas Moore
- Biological and Environmental Sciences, University of Stirling, Stirling, FK9 4LA, UK.
| | - Dudley I Farman
- Natural Resources Institute, University of Greenwich, Kent, ME4 4TB, UK
| | - Tiina Särkinen
- Royal Botanic Garden Edinburgh, 20A Inverleith Row, Edinburgh, EH3 5LR, UK
| | - Philip C Stevenson
- Natural Resources Institute, University of Greenwich, Kent, ME4 4TB, UK
- Royal Botanic Gardens, Kew Green, Kew, Richmond, Surrey, TW9 3AE, UK
| | - Mario Vallejo-Marín
- Biological and Environmental Sciences, University of Stirling, Stirling, FK9 4LA, UK
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, 752 36, Uppsala, Sweden
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2
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Barragán‐Fonseca KY, Rusman Q, Mertens D, Weldegergis BT, Peller J, Polder G, van Loon JJA, Dicke M. Insect exuviae as soil amendment affect flower reflectance and increase flower production and plant volatile emission. PLANT, CELL & ENVIRONMENT 2023; 46:931-945. [PMID: 36514238 PMCID: PMC10107842 DOI: 10.1111/pce.14516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 12/06/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
Soil composition and herbivory are two environmental factors that can affect plant traits including flower traits, thus potentially affecting plant-pollinator interactions. Importantly, soil composition and herbivory may interact in these effects, with consequences for plant fitness. We assessed the main effects of aboveground insect herbivory and soil amendment with exuviae of three different insect species on visual and olfactory traits of Brassica nigra plants, including interactive effects. We combined various methodological approaches including gas chromatography/mass spectrometry, spectroscopy and machine learning to evaluate changes in flower morphology, colour and the emission of volatile organic compounds (VOCs). Soil amended with insect exuviae increased the total number of flowers per plant and VOC emission, whereas herbivory reduced petal area and VOC emission. Soil amendment and herbivory interacted in their effect on the floral reflectance spectrum of the base part of petals and the emission of 10 VOCs. These findings demonstrate the effects of insect exuviae as soil amendment on plant traits involved in reproduction, with a potential for enhanced reproductive success by increasing the strength of signals attracting pollinators and by mitigating the negative effects of herbivory.
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Affiliation(s)
- Katherine Y. Barragán‐Fonseca
- Laboratory of EntomologyWageningen University & ResearchWageningenThe Netherlands
- Grupo en Conservación y Manejo de Vida Silvestre, Instituto de Ciencias NaturalesUniversidad Nacional de ColombiaBogotáColombia
| | - Quint Rusman
- Laboratory of EntomologyWageningen University & ResearchWageningenThe Netherlands
| | - Daan Mertens
- Department of Entomology and NematologyUniversity of CaliforniaDavisCaliforniaUSA
| | | | - Joseph Peller
- Greenhouse HorticultureWageningen University & ResearchWageningenThe Netherlands
| | - Gerrit Polder
- Greenhouse HorticultureWageningen University & ResearchWageningenThe Netherlands
| | - Joop J. A. van Loon
- Laboratory of EntomologyWageningen University & ResearchWageningenThe Netherlands
| | - Marcel Dicke
- Laboratory of EntomologyWageningen University & ResearchWageningenThe Netherlands
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3
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Floral scent divergence across an elevational hybrid zone with varying pollinators. Oecologia 2023; 201:45-57. [PMID: 36374316 DOI: 10.1007/s00442-022-05289-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 11/08/2022] [Indexed: 11/16/2022]
Abstract
Divergence in floral traits attractive to different pollinators can promote reproductive isolation in related species. When isolation is incomplete, hybridization may occur, which offers the opportunity to explore mechanisms underlying reproductive isolation. Recent work suggests that divergence in floral scent may frequently contribute to reproductive barriers, although such divergence has seldom been examined in species with generalized pollination. Here, we used two closely related Penstemon species, P. newberryi and P. davidsonii, and their natural hybrids from an elevational gradient with pollinator communities that are predicted to vary in their reliance on floral scent (i.e., primarily hummingbirds at low elevation vs. bees at high elevation). The species vary in a suite of floral traits, but scent is uncharacterized. To address whether scent varies along elevation and potentially contributes to reproductive isolation, we genetically characterized individuals collected at field and identified whether they were parental species or hybrids. We then characterized scent amount and composition. Although the parental species had similar total emissions, some scent characteristics (i.e., scent composition, aromatic emission) diverged between them and may contribute to their isolation. However, the species emitted similar compound sets which could explain hybridization in the contact area. Hybrids were similar to the parents for most scent traits, suggesting that their floral scent would not provide a strong barrier to backcrossing. Our study suggests floral scent may be a trait contributing to species boundaries even in plants with generalized pollination, and reinforces the idea that evolutionary pollinator transitions may involve changes in multiple floral traits.
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4
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Fan S, Jia Y, Wang R, Chen X, Liu W, Yu H. Multi-omics analysis the differences of VOCs terpenoid synthesis pathway in maintaining obligate mutualism between Ficus hirta Vahl and its pollinators. FRONTIERS IN PLANT SCIENCE 2022; 13:1006291. [PMID: 36457527 PMCID: PMC9707799 DOI: 10.3389/fpls.2022.1006291] [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: 07/29/2022] [Accepted: 11/01/2022] [Indexed: 06/17/2023]
Abstract
INRODUCTION Volatile organic compounds (VOCs) emitted by the receptive syconia of Ficus species is a key trait to attract their obligate pollinating fig wasps. Ficus hirta Vahl is a dioecious shrub, which is pollinated by a highly specialized symbiotic pollinator in southern China. Terpenoids are the main components of VOCs in F. hirta and play ecological roles in pollinator attraction, allelopathy, and plant defense. However, it remains unclear that what molecular mechanism difference in terpenoid synthesis pathways between pre-receptive stage (A-phase) and receptive stage (B-phase) of F. hirta syconia. METHODS Transcriptome, proteome and Gas Chromatography-Mass Spectrometer (GC-MS) were applied here to analyze these difference. RESULTS AND DISCUSSION Compared to A-phase syconia, the genes (ACAT2, HMGR3, GGPS2, HDR, GPS2, TPS2, TPS4, TPS10-4, TPS14) related to the terpenoid synthesis pathway had higher expression level in receptive syconia (B-phase) according to transcriptome sequencing. Seven differentially expressed transcription factors were screened, namely bHLH7, MYB1R1, PRE6, AIL1, RF2b, ANT, VRN1. Specifically, bHLH7 was only specifically expressed in B-phase. 235 differentially expressed proteins (DEPs) were mainly located in the cytoplasm and chloroplasts. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the DEPs were mainly enriched in the metabolic process. A total of 9 terpenoid synthesis proteins were identified in the proteome. Among them, 4 proteins in methylerythritol phosphate (MEP) pathway were all down-regulated. Results suggested the synthesis of terpenoids precursors in B-phase bracts were mainly accomplished through the mevalonic acid (MVA) pathway in cytoplasm. Correlation analysis between the transcriptome and proteome, we detected a total of 1082 transcripts/proteins, three of which are related to stress. From the VOCs analysis, the average percent of monoterpenoids emitted by A-phase and B-phase syconia were 8.29% and 37.08%, while those of sesquiterpenes were 88.43% and 55.02% respectively. Monoterpenes (camphene, myrcene, camphor, menthol) were only detected in VOCs of B-phase syconia. To attract pollinators, B-phase syconia of F. hirta need more monoterpenoids and less sesquiterpenes. We speculate that transcription factor bHLH7 may regulate the terpenoid synthesis pathway between A- and B-phase syconia. Our research provided the first global analysis of mechanism differences of terpenoid synthesis pathways between A and B phases in F. hirta syconia.
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Affiliation(s)
- Songle Fan
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- Guangdong Provincial Key Laboratory of Digital Botanical Garden, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yongxia Jia
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Rong Wang
- School of Ecological and Environmental Sciences, Tiantong National Station for Forest Ecosystem Research, East China Normal University, Shanghai, China
| | - Xiaoyong Chen
- School of Ecological and Environmental Sciences, Tiantong National Station for Forest Ecosystem Research, East China Normal University, Shanghai, China
| | - Wanzhen Liu
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- Guangdong Provincial Key Laboratory of Digital Botanical Garden, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Hui Yu
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- Guangdong Provincial Key Laboratory of Digital Botanical Garden, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
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5
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Eisen KE, Ma R, Raguso RA. Among- and within-population variation in morphology, rewards, and scent in a hawkmoth-pollinated plant. AMERICAN JOURNAL OF BOTANY 2022; 109:1794-1810. [PMID: 35762273 DOI: 10.1002/ajb2.16030] [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: 01/20/2022] [Revised: 05/24/2022] [Accepted: 05/25/2022] [Indexed: 06/15/2023]
Abstract
PREMISE Floral scent is a complex trait that mediates many plant-insect interactions, but our understanding of how floral scent variation evolves, either independently or in concert with other traits, remains limited. Assessing variation in floral scent at multiple levels of biological organization and comparing patterns of variation in scent to variation in other floral traits can contribute to our understanding of how scent variation evolves in nature. METHODS We used a greenhouse common garden experiment to investigate variation in floral scent at three scales-within plants, among plants, and among populations-and to determine whether scent, alone or in combination with morphology and rewards, contributes to population differentiation in Oenothera cespitosa subsp. marginata. Its range spans most of the biomes in the western United States, such that variation in both the abiotic and biotic environment could contribute to trait variation. RESULTS Multiple analytical approaches demonstrated substantial variation among and within populations in compound-specific and total floral scent measures. Overall, populations were differentiated in morphology and reward traits and in scent. Across populations, coupled patterns of variation in linalool, leucine-derived compounds, and hypanthium length are consistent with a long-tongued moth pollination syndrome. CONCLUSIONS The considerable variation in floral scent detected within populations suggests that, similar to other floral traits, variation in floral scent may have a heritable genetic component. Differences in patterns of population differentiation in floral scent and in morphology and rewards indicate that these traits may be shaped by different selective pressures.
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Affiliation(s)
- Katherine E Eisen
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, 14853, USA
- Department of Biology, Lund University, Lund, Sweden
| | - Rong Ma
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY, 14853, USA
| | - Robert A Raguso
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY, 14853, USA
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6
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Liu J, Zhang J, Shen J, Zhao H, Ma W, Jiang Y. Differences in EAG Response and Behavioral Choices between Honey Bee and Bumble Bee to Tomato Flower Volatiles. INSECTS 2022; 13:insects13110987. [PMID: 36354811 PMCID: PMC9697709 DOI: 10.3390/insects13110987] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 10/24/2022] [Accepted: 10/26/2022] [Indexed: 05/24/2023]
Abstract
Bumble bees and honey bees are of vital importance for tomato pollination, although honey bees are less attracted to tomato flowers than bumble bees. Little is known about how tomato flower volatile compounds influence the foraging behaviors of honey bees and bumble bees. In this study, compounds of tomato flower volatiles were detected by gas chromatography-mass spectrometry. Electroantennography (EAG) and a dynamic two-choice olfactometer were used, respectively, to compare the differences of antennal and behavioral responses between Apis mellifera and Bombus terrestris towards selected volatile compounds. A total of 46 compounds were detected from the tomato flower volatiles. Of the 16 compounds tested, A. mellifera showed strong antennal responses to 3 compounds (1-nonanal, (+)-dihydrocarvone, and toluene) when compared with a mineral oil control, and B. terrestris showed 7 pronounced EAG responses (1,3-xylene, (+)-dihydrocarvone, toluene, piperitone, eucarvone, 1-nonanal, and β-ocimene). Additionally, 1-nonanal and (+)-dihydrocarvone elicited significant avoidance behavior of A. mellifera, but not of B. terrestris. In conclusion, bumble bees are more sensitive to the compounds of tomato flower volatiles compared to honey bees, and honey bees showed aversion to some compounds of tomato flower volatiles. The findings indicated that compounds of flower volatiles significantly influenced bee foraging preference for tomato.
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Affiliation(s)
- Jinjia Liu
- College of Animal Science, Shanxi Agricultural University, Jinzhong 030801, China
| | - Jiangchao Zhang
- College of Animal Science, Shanxi Agricultural University, Jinzhong 030801, China
| | - Jinshan Shen
- College of Horticulture, Shanxi Agricultural University, Taiyuan 030031, China
| | - Huiting Zhao
- College of Life Sciences, Shanxi Agricultural University, Jinzhong 030801, China
| | - Weihua Ma
- College of Horticulture, Shanxi Agricultural University, Taiyuan 030031, China
| | - Yusuo Jiang
- College of Animal Science, Shanxi Agricultural University, Jinzhong 030801, China
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7
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Erickson E, Junker RR, Ali JG, McCartney N, Patch HM, Grozinger CM. Complex floral traits shape pollinator attraction to ornamental plants. ANNALS OF BOTANY 2022; 130:561-577. [PMID: 35732011 PMCID: PMC9510942 DOI: 10.1093/aob/mcac082] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND AND AIMS Ornamental flowering plant species are often used in managed greenspaces to attract and support pollinator populations. In natural systems, selection by pollinators is hypothesized to result in convergent multimodal floral phenotypes that are more attractive to specific pollinator taxa. In contrast, ornamental cultivars are bred via artificial selection by humans, and exhibit diverse and distinct phenotypes. Despite their prevalence in managed habitats, the influence of cultivar phenotypic variation on plant attractiveness to pollinator taxa is not well resolved. METHODS We used a combination of field and behavioural assays to evaluate how variation in floral visual, chemical and nutritional traits impacted overall attractiveness and visitation by pollinator taxonomic groups and bee species to 25 cultivars of five herbaceous perennial ornamental plant genera. KEY RESULTS Despite significant phenotypic variation, cultivars tended to attract a broad range of pollinator species. Nonetheless, at the level of insect order (bee, fly, butterfly, beetle), attraction was generally modulated by traits consistent with the pollination syndrome hypothesis. At the level of bee species, the relative influence of traits on visitation varied across plant genera, with some floral phenotypes leading to a broadening of the visitor community, and others leading to exclusion of visitation by certain bee species. CONCLUSIONS Our results demonstrate how pollinator choice is mediated by complex multimodal floral signals. Importantly, the traits that had the greatest and most consistent effect on regulating pollinator attraction were those that are commonly selected for in cultivar development. Though variation among cultivars in floral traits may limit the pollinator community by excluding certain species, it may also encourage interactions with generalist taxa to support pollinator diversity in managed landscapes.
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Affiliation(s)
| | - R R Junker
- Evolutionary Ecology of Plants, Department of Biology, University of Marburg, 35043 Marburg, Germany
- Department of Environment and Biodiversity, University of Salzburg, Salzburg, Austria
| | - J G Ali
- Department of Entomology, Center for Pollinator Research, Huck Institutes of the Life Sciences, Pennsylvania State University, ASI Building University Park, PA, USA
| | - N McCartney
- Department of Entomology, Center for Pollinator Research, Huck Institutes of the Life Sciences, Pennsylvania State University, ASI Building University Park, PA, USA
| | - H M Patch
- Department of Entomology, Center for Pollinator Research, Huck Institutes of the Life Sciences, Pennsylvania State University, ASI Building University Park, PA, USA
| | - C M Grozinger
- Department of Entomology, Center for Pollinator Research, Huck Institutes of the Life Sciences, Pennsylvania State University, ASI Building University Park, PA, USA
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8
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Szenteczki MA, Godschalx AL, Gauthier J, Gibernau M, Rasmann S, Alvarez N. Transcriptomic analysis of deceptively pollinated Arum maculatum (Araceae) reveals association between terpene synthase expression in floral trap chamber and species-specific pollinator attraction. G3 (BETHESDA, MD.) 2022; 12:jkac175. [PMID: 35861391 PMCID: PMC9434142 DOI: 10.1093/g3journal/jkac175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 06/30/2022] [Indexed: 06/15/2023]
Abstract
Deceptive pollination often involves volatile organic compound emissions that mislead insects into performing nonrewarding pollination. Among deceptively pollinated plants, Arum maculatum is particularly well-known for its potent dung-like volatile organic compound emissions and specialized floral chamber, which traps pollinators-mainly Psychoda phalaenoides and Psychoda grisescens-overnight. However, little is known about the genes underlying the production of many Arum maculatum volatile organic compounds, and their influence on variation in pollinator attraction rates. Therefore, we performed de novo transcriptome sequencing of Arum maculatum appendix and male floret tissue collected during anthesis and postanthesis, from 10 natural populations across Europe. These RNA-seq data were paired with gas chromatography-mass spectrometry analyses of floral scent composition and pollinator data collected from the same inflorescences. Differential expression analyses revealed candidate transcripts in appendix tissue linked to malodourous volatile organic compounds including indole, p-cresol, and 2-heptanone. In addition, we found that terpene synthase expression in male floret tissue during anthesis significantly covaried with sex- and species-specific attraction of Psychoda phalaenoides and Psychoda grisescens. Taken together, our results provide the first insights into molecular mechanisms underlying pollinator attraction patterns in Arum maculatum and highlight floral chamber sesquiterpene (e.g. bicyclogermacrene) synthases as interesting candidate genes for further study.
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Affiliation(s)
- Mark A Szenteczki
- Corresponding author: Université de Neuchâtel, Institut de Biologie, Rue Emile-Argand 11, Neuchâtel 2000, Switzerland. E-mail
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9
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Cao Y, Liu L, Ma K, Wang W, Lv H, Gao M, Wang X, Zhang X, Ren S, Zhang N, Guo YD. The jasmonate-induced bHLH gene SlJIG functions in terpene biosynthesis and resistance to insects and fungus. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2022; 64:1102-1115. [PMID: 35293128 DOI: 10.1111/jipb.13248] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 03/14/2022] [Indexed: 05/27/2023]
Abstract
Jasmonic acid (JA) is a key regulator of plant defense responses. Although the transcription factor MYC2, the master regulator of the JA signaling pathway, orchestrates a hierarchical transcriptional cascade that regulates the JA responses, only a few transcriptional regulators involved in this cascade have been described. Here, we identified the basic helix-loop-helix (bHLH) transcription factor gene in tomato (Solanum lycopersicum), METHYL JASMONATE (MeJA)-INDUCED GENE (SlJIG), the expression of which was strongly induced by MeJA treatment. Genetic and molecular biology experiments revealed that SlJIG is a direct target of MYC2. SlJIG knockout plants generated by gene editing had lower terpene contents than the wild type from the lower expression of TERPENE SYNTHASE (TPS) genes, rendering them more appealing to cotton bollworm (Helicoverpa armigera). Moreover, SlJIG knockouts exhibited weaker JA-mediated induction of TPSs, suggesting that SlJIG may participate in JA-induced terpene biosynthesis. Knocking out SlJIG also resulted in attenuated expression of JA-responsive defense genes, which may contribute to the observed lower resistance to cotton bollworm and to the fungus Botrytis cinerea. We conclude that SlJIG is a direct target of MYC2, forms a MYC2-SlJIG module, and functions in terpene biosynthesis and resistance against cotton bollworm and B. cinerea.
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Affiliation(s)
- Yunyun Cao
- College of Horticulture, China Agricultural University, Beijing, 100193, China
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai'an, 271018, China
| | - Lun Liu
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Kangsheng Ma
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China
| | - Wenjing Wang
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Hongmei Lv
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Ming Gao
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Xinman Wang
- College of Horticulture, China Agricultural University, Beijing, 100193, China
| | - Xichun Zhang
- College of Plant Science and Technology, Beijing University of Agriculture, Beijing, 102206, China
| | - Shuxin Ren
- School of Agriculture, Virginia State University, Petersburg, 23806, VA, USA
| | - Na Zhang
- College of Horticulture, China Agricultural University, Beijing, 100193, China
- Sanya Institute of China Agricultural University, Sanya, 572000, China
| | - Yang-Dong Guo
- College of Horticulture, China Agricultural University, Beijing, 100193, China
- Sanya Institute of China Agricultural University, Sanya, 572000, China
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10
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Boersma MR, Patrick RM, Jillings SL, Shaipulah NFM, Sun P, Haring MA, Dudareva N, Li Y, Schuurink RC. ODORANT1 targets multiple metabolic networks in petunia flowers. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 109:1134-1151. [PMID: 34863006 PMCID: PMC9306810 DOI: 10.1111/tpj.15618] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 11/23/2021] [Accepted: 11/27/2021] [Indexed: 05/19/2023]
Abstract
Scent bouquets produced by the flowers of Petunia spp. (petunia) are composed of a complex mixture of floral volatile benzenoid and phenylpropanoid compounds (FVBPs), which are specialized metabolites derived from phenylalanine (Phe) through an interconnected network of enzymes. The biosynthesis and emission of high levels of these volatiles requires coordinated transcriptional activation of both primary and specialized metabolic networks. The petunia R2R3-MYB transcription factor ODORANT 1 (ODO1) was identified as a master regulator of FVBP production and emission; however, our knowledge of the direct regulatory targets of ODO1 has remained limited. Using chromatin immunoprecipitation followed by sequencing (ChIP-seq) in petunia flowers, we identify genome-wide ODO1-bound genes that are enriched not only in genes involved in the biosynthesis of the Phe precursor, as previously reported, but also genes associated with the specialized metabolic pathways involved in generating phenylpropanoid intermediates for FVBPs. ODO1-bound genes are also involved in methionine and S-adenosylmethionine metabolism, which could modulate methyl group supplies for certain FVBPs. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and RNA-seq analysis in an ODO1 RNAi knockdown line revealed that ODO1-bound targets are expressed at lower levels when ODO1 is suppressed. A cis-regulatory motif, CACCAACCCC, was identified as a potential binding site for ODO1 in the promoters of genes that are both bound and activated by ODO1, which was validated by in planta promoter reporter assays with wild-type and mutated promoters. Overall, our work presents a mechanistic model for ODO1 controlling an extensive gene regulatory network that contributes to FVBP production to give rise to floral scent.
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Affiliation(s)
- Maaike R. Boersma
- Green Life Sciences Research ClusterSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdam1098 XHthe Netherlands
- Green BiotechnologyInholland University of Applied SciencesAmsterdam1098 XHthe Netherlands
| | - Ryan M. Patrick
- Department of Horticulture and Landscape ArchitecturePurdue UniversityWest LafayetteIN47907USA
- Purdue Center for Plant BiologyPurdue UniversityWest LafayetteIN47907USA
| | - Sonia L. Jillings
- Green Life Sciences Research ClusterSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdam1098 XHthe Netherlands
| | - Nur Fariza M. Shaipulah
- Green Life Sciences Research ClusterSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdam1098 XHthe Netherlands
- Present address:
Faculty of Science and Marine EnvironmentUniversiti Malaysia Terrengganu21030 Kuala NerusTerrenganuMalaysia
| | - Pulu Sun
- Green Life Sciences Research ClusterSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdam1098 XHthe Netherlands
| | - Michel A. Haring
- Green Life Sciences Research ClusterSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdam1098 XHthe Netherlands
| | - Natalia Dudareva
- Department of Horticulture and Landscape ArchitecturePurdue UniversityWest LafayetteIN47907USA
- Purdue Center for Plant BiologyPurdue UniversityWest LafayetteIN47907USA
- Department of BiochemistryPurdue UniversityWest LafayetteIN47907USA
| | - Ying Li
- Department of Horticulture and Landscape ArchitecturePurdue UniversityWest LafayetteIN47907USA
- Purdue Center for Plant BiologyPurdue UniversityWest LafayetteIN47907USA
| | - Robert C. Schuurink
- Green Life Sciences Research ClusterSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdam1098 XHthe Netherlands
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11
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Manincor N, Andreu B, Buatois B, Lou Chao H, Hautekèete N, Massol F, Piquot Y, Schatz B, Schmitt E, Dufay M. Geographical variation of floral scents in generalist entomophilous species with variable pollinator communities. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
| | - Benjamin Andreu
- CEFE Univ. Montpellier CNRS EPHE IRD Univ. Paul Valéry Montpellier 3 Montpellier France
| | - Bruno Buatois
- CEFE Univ. Montpellier CNRS EPHE IRD Univ. Paul Valéry Montpellier 3 Montpellier France
| | | | | | - François Massol
- Univ. Lille CNRS UMR 8198—Evo‐Eco‐Paleo Lille France
- Univ. Lille CNRS Inserm CHU Lille Institut Pasteur de Lille U1019—UMR 9017—CIIL—Center for Infection and Immunity of Lille Lille France
| | - Yves Piquot
- Univ. Lille CNRS UMR 8198—Evo‐Eco‐Paleo Lille France
| | - Bertrand Schatz
- CEFE Univ. Montpellier CNRS EPHE IRD Univ. Paul Valéry Montpellier 3 Montpellier France
| | - Eric Schmitt
- Univ. Lille CNRS UMR 8198—Evo‐Eco‐Paleo Lille France
| | - Mathilde Dufay
- Univ. Lille CNRS UMR 8198—Evo‐Eco‐Paleo Lille France
- CEFE Univ. Montpellier CNRS EPHE IRD Univ. Paul Valéry Montpellier 3 Montpellier France
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12
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Knauer AC, Kokko H, Schiestl FP. Pollinator behaviour and resource limitation maintain honest floral signalling. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Anina C. Knauer
- Department of Systematic and Evolutionary Botany University of Zurich Zürich Switzerland
| | - Hanna Kokko
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zürich Switzerland
| | - Florian P. Schiestl
- Department of Systematic and Evolutionary Botany University of Zurich Zürich Switzerland
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13
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Espadas-Pinacho K, López-Guillén G, Gómez-Ruiz J, Cruz-López L. Induced volatiles in the interaction between soybean (Glycine max) and the Mexican soybean weevil (Rhyssomatus nigerrimus). BRAZ J BIOL 2021; 81:611-620. [PMID: 32935818 DOI: 10.1590/1519-6984.227271] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Accepted: 02/26/2020] [Indexed: 11/22/2022] Open
Abstract
The present study analyzed the volatile compounds emitted by Glycine max (cv. FT-Cristalina-RCH) soybean plants: healthy plants and plants damaged mechanically or by the Mexican soybean weevil Rhyssomatus nigerrimus. The SPME method was used to compare the volatile profile of soybean plants in four different conditions. The volatile profile of G. max plants infested by R. nigerrimus was qualitatively and quantitatively different from that of healthy and mechanically damaged plants. Emission of 59 compounds was detected in the four treatments. Of these compounds, 19 were identified by comparison of the Kovats index, mass spectrum and retention times with those of synthetic standards. An increase in concentration of the volatiles (Z)-3-hexenyl acetate and the compound 1-octen-3-ol was observed when the soybean plants were mechanically damaged. The compounds mostly produced by the soybean plant during infestation by male and female R. nigerrimus were 1-octen-3-ol, 6-methyl-5-hepten-2-one, (E)-β-ocimene, salicylaldehyde, unknown 10, linalool, methyl salicylate, (Z)-8-dodecenyl acetate (ester 5), ketone 2 and geranyl acetone. Behavioral effects of the identified compounds during the insect-plant interaction and their conspecifics are discussed.
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Affiliation(s)
- K Espadas-Pinacho
- El Colegio de la Frontera Sur - ECOSUR, Grupo de Ecología de Artrópodos y Manejo de Plagas, Tapachula, Chiapas, Mexico
| | - G López-Guillén
- Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias - INIFAP, Campo Experimental Rosario Izapa, Tuxtla Chico, Chiapas, Mexico
| | - J Gómez-Ruiz
- El Colegio de la Frontera Sur - ECOSUR, Grupo de Ecología de Artrópodos y Manejo de Plagas, Tapachula, Chiapas, Mexico
| | - L Cruz-López
- El Colegio de la Frontera Sur - ECOSUR, Grupo de Ecología de Artrópodos y Manejo de Plagas, Tapachula, Chiapas, Mexico
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14
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Biochemistry of Terpenes and Recent Advances in Plant Protection. Int J Mol Sci 2021; 22:ijms22115710. [PMID: 34071919 PMCID: PMC8199371 DOI: 10.3390/ijms22115710] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/20/2021] [Accepted: 05/24/2021] [Indexed: 01/23/2023] Open
Abstract
Biodiversity is adversely affected by the growing levels of synthetic chemicals released into the environment due to agricultural activities. This has been the driving force for embracing sustainable agriculture. Plant secondary metabolites offer promising alternatives for protecting plants against microbes, feeding herbivores, and weeds. Terpenes are the largest among PSMs and have been extensively studied for their potential as antimicrobial, insecticidal, and weed control agents. They also attract natural enemies of pests and beneficial insects, such as pollinators and dispersers. However, most of these research findings are shelved and fail to pass beyond the laboratory and greenhouse stages. This review provides an overview of terpenes, types, biosynthesis, and their roles in protecting plants against microbial pathogens, insect pests, and weeds to rekindle the debate on using terpenes for the development of environmentally friendly biopesticides and herbicides.
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15
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Patrick RM, Huang XQ, Dudareva N, Li Y. Dynamic histone acetylation in floral volatile synthesis and emission in petunia flowers. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:3704-3722. [PMID: 33606881 PMCID: PMC8096599 DOI: 10.1093/jxb/erab072] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 02/15/2021] [Indexed: 05/29/2023]
Abstract
Biosynthesis of secondary metabolites relies on primary metabolic pathways to provide precursors, energy, and cofactors, thus requiring coordinated regulation of primary and secondary metabolic networks. However, to date, it remains largely unknown how this coordination is achieved. Using Petunia hybrida flowers, which emit high levels of phenylpropanoid/benzenoid volatile organic compounds (VOCs), we uncovered genome-wide dynamic deposition of histone H3 lysine 9 acetylation (H3K9ac) during anthesis as an underlying mechanism to coordinate primary and secondary metabolic networks. The observed epigenome reprogramming is accompanied by transcriptional activation at gene loci involved in primary metabolic pathways that provide precursor phenylalanine, as well as secondary metabolic pathways to produce volatile compounds. We also observed transcriptional repression among genes involved in alternative phenylpropanoid branches that compete for metabolic precursors. We show that GNAT family histone acetyltransferase(s) (HATs) are required for the expression of genes involved in VOC biosynthesis and emission, by using chemical inhibitors of HATs, and by knocking down a specific HAT gene, ELP3, through transient RNAi. Together, our study supports that regulatory mechanisms at chromatin level may play an essential role in activating primary and secondary metabolic pathways to regulate VOC synthesis in petunia flowers.
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Affiliation(s)
- Ryan M Patrick
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907,USA
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907,USA
| | - Xing-Qi Huang
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907,USA
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907,USA
| | - Natalia Dudareva
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907,USA
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907,USA
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907,USA
| | - Ying Li
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN 47907,USA
- Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907,USA
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16
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Byers KJRP. "As if they discovered it by the scent": improving our understanding of the chemical ecology, evolution, and genetics of floral scent and its role in pollination. AMERICAN JOURNAL OF BOTANY 2021; 108:729-731. [PMID: 34008177 DOI: 10.1002/ajb2.1661] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Affiliation(s)
- Kelsey J R P Byers
- Department of Cell and Developmental Biology, John Innes Centre, Norwich, UK
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17
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Byers KJRP, Bradshaw HD. Rational Design of a Novel Hawkmoth Pollinator Interaction in Mimulus Section Erythranthe. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.658710] [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
Diversification of theca. 275,000 extant flowering plant species has been driven in large part by coevolution with animal pollinators. A recurring pattern of pollinator shifts from hummingbird to hawkmoth pollination has characterized plant speciation in many western North American plant taxa, but in the genusMimulus(monkeyflowers) sectionErythranthethe evolution of hawkmoth pollination from hummingbird-pollinated ancestors has not occurred. We manipulated two flower color loci and tested the attractiveness of the resulting four color phenotypes (red, yellow, pink, and white) to naïve hawkmoths (Manduca sexta). Hawkmoths strongly prefer derived colors (yellow, pink, white) over the ancestral red when choosing an initial flower to visit, and generally preferred derived colors when total visits and total visit time were considered, with no hawkmoth preferring ancestral red over derived colors. The simple flower color genetics underlying this innate pollinator preference suggests a potential path for speciation into an unfilled hawkmoth-pollinated niche inMimulussectionErythranthe, and the deliberate design of a hawkmoth-pollinated flower demonstrates a new, predictive method for studying pollination syndrome evolution.
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18
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Orsucci M, Sicard A. Flower evolution in the presence of heterospecific gene flow and its contribution to lineage divergence. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:971-989. [PMID: 33537708 DOI: 10.1093/jxb/eraa549] [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: 08/10/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Abstract
The success of species depends on their ability to exploit ecological resources in order to optimize their reproduction. However, species are not usually found within single-species ecosystems but in complex communities. Because of their genetic relatedness, closely related lineages tend to cluster within the same ecosystem, rely on the same resources, and be phenotypically similar. In sympatry, they will therefore compete for the same resources and, in the case of flowering plants, exchange their genes through heterospecific pollen transfer. These interactions, nevertheless, pose significant challenges to species co-existence because they can lead to resource limitation and reproductive interference. In such cases, divergent selective pressures on floral traits will favour genotypes that isolate or desynchronize the reproduction of sympatric lineages. The resulting displacement of reproductive characters will, in turn, lead to pre-mating isolation and promote intraspecific divergence, thus initiating or reinforcing the speciation process. In this review, we discuss the current theoretical and empirical knowledge on the influence of heterospecific pollen transfer on flower evolution, highlighting its potential to uncover the ecological and genomic constraints shaping the speciation process.
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Affiliation(s)
- Marion Orsucci
- Department of Plant Biology, Swedish University of Agricultural, Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Adrien Sicard
- Department of Plant Biology, Swedish University of Agricultural, Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
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19
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Tools to Tie: Flower Characteristics, VOC Emission Profile, and Glandular Trichomes of Two Mexican Salvia Species to Attract Bees. PLANTS 2020; 9:plants9121645. [PMID: 33255733 PMCID: PMC7760984 DOI: 10.3390/plants9121645] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 11/17/2020] [Accepted: 11/20/2020] [Indexed: 11/29/2022]
Abstract
A plant can combine physical and chemical tools to interact with other organisms. Some are designed for pollinator attraction (i.e., colors and volatile organic compounds-VOCs); others can act to discourage herbivores (i.e., non-glandular trichomes). Few studies fully address available tools in a single species; notwithstanding, this information can be pivotal in understanding new interactions out of the home range. We characterized flower traits, emission profiles of constitutive compounds from flowers and leaves, micro-morphology of the glandular trichomes, and listed flower visitors of two Mexican bird-pollinated Salvia species (S. blepharophylla and S. greggii), growing in an Italian botanical garden. Flowers were highly variable in their morphometric characteristics. In both species, four trichome morphotypes with similar histochemistry and distribution were documented for leaves and flowers except the calyx abaxial side. The vegetative emission profiles were qualitatively more complex than the floral ones; however, common compounds occurring in high relative percentages were β-caryophyllene and germacrene D. Floral bouquets were dominated by limonene and β-pinene in S. greggii and by 1,8-cineole in S. blepharophylla. Two potential (non-bird) pollinators were especially abundant: small bees belonging to the genus Lasioglossum and large bees belonging to the species Xylocopa violacea. Our study highlights the plasticity of these plants, as well as tools that can be conveniently used to establish novel interactions.
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20
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Whitney KD, Smith AK, White TE, Williams CF. Birds Perceive More Intraspecific Color Variation in Bird-Pollinated Than Bee-Pollinated Flowers. FRONTIERS IN PLANT SCIENCE 2020; 11:590347. [PMID: 33281850 PMCID: PMC7705070 DOI: 10.3389/fpls.2020.590347] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Accepted: 10/27/2020] [Indexed: 06/12/2023]
Abstract
Pollinator-mediated selection is expected to constrain floral color variation within plant populations. Here, we test for patterns of constraint on floral color variation in 38 bee- and/or hummingbird-pollinated plant species from Colorado, United States. We collected reflectance spectra for at least 15 individuals in each of 1-3 populations of each species (total 78 populations) and modeled perceived color variation in both bee and bird visual spaces. We hypothesized that bees would perceive less intraspecific color variation in bee-pollinated species (vs. bird-pollinated species), and reciprocally, birds would perceive less color variation in bird-pollinated species (vs. bee-pollinated species). In keeping with the higher dimensionality of the bird visual system, birds typically perceived much more color variation than bees, regardless of plant pollination system. Contrary to our hypothesis, bees perceived equal color variation within plant species from the two pollination systems, and birds perceived more color variation in species that they pollinate than in bee-pollinated species. We propose hypotheses to account for the results, including reduced long-wavelength sensitivity in bees (vs. birds), and the ideas that potential categorical color vision in birds and larger cognitive capacities of birds (vs. bees) reduces their potential discrimination against floral color variants in species that they pollinate, resulting in less stabilizing selection on color within bird-pollinated vs. bee-pollinated species.
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Affiliation(s)
- Kenneth D. Whitney
- Department of Biology, University of New Mexico, Albuquerque, NM, United States
- Rocky Mountain Biological Laboratory, Crested Butte, CO, United States
| | - Asher K. Smith
- Rocky Mountain Biological Laboratory, Crested Butte, CO, United States
| | - Thomas E. White
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Charles F. Williams
- Rocky Mountain Biological Laboratory, Crested Butte, CO, United States
- Department of Biological Sciences, Idaho State University, Pocatello, ID, United States
- Ray J. Davis Herbarium, Idaho Museum of Natural History, Pocatello, ID, United States
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21
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Boncan DAT, Tsang SS, Li C, Lee IH, Lam HM, Chan TF, Hui JH. Terpenes and Terpenoids in Plants: Interactions with Environment and Insects. Int J Mol Sci 2020; 21:E7382. [PMID: 33036280 PMCID: PMC7583029 DOI: 10.3390/ijms21197382] [Citation(s) in RCA: 117] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/01/2020] [Accepted: 10/01/2020] [Indexed: 02/07/2023] Open
Abstract
The interactions of plants with environment and insects are bi-directional and dynamic. Consequently, a myriad of mechanisms has evolved to engage organisms in different types of interactions. These interactions can be mediated by allelochemicals known as volatile organic compounds (VOCs) which include volatile terpenes (VTs). The emission of VTs provides a way for plants to communicate with the environment, including neighboring plants, beneficiaries (e.g., pollinators, seed dispersers), predators, parasitoids, and herbivores, by sending enticing or deterring signals. Understanding terpenoid distribution, biogenesis, and function provides an opportunity for the design and implementation of effective and efficient environmental calamity and pest management strategies. This review provides an overview of plant-environment and plant-insect interactions in the context of terpenes and terpenoids as important chemical mediators of these abiotic and biotic interactions.
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Affiliation(s)
- Delbert Almerick T. Boncan
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong;
- Center for Soybean Research of the State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Stacey S.K. Tsang
- Simon F.S. Li Marine Science Laboratory, The Chinese University of Hong Kong, Shatin, Hong Kong; (S.S.K.T.); (C.L.); (I.H.T.L.)
| | - Chade Li
- Simon F.S. Li Marine Science Laboratory, The Chinese University of Hong Kong, Shatin, Hong Kong; (S.S.K.T.); (C.L.); (I.H.T.L.)
| | - Ivy H.T. Lee
- Simon F.S. Li Marine Science Laboratory, The Chinese University of Hong Kong, Shatin, Hong Kong; (S.S.K.T.); (C.L.); (I.H.T.L.)
| | - Hon-Ming Lam
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong;
- Center for Soybean Research of the State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Ting-Fung Chan
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong;
- Center for Soybean Research of the State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Jerome H.L. Hui
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong;
- Center for Soybean Research of the State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
- Simon F.S. Li Marine Science Laboratory, The Chinese University of Hong Kong, Shatin, Hong Kong; (S.S.K.T.); (C.L.); (I.H.T.L.)
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22
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Yu Z, Zhao C, Zhang G, Teixeira da Silva JA, Duan J. Genome-Wide Identification and Expression Profile of TPS Gene Family in Dendrobium officinale and the Role of DoTPS10 in Linalool Biosynthesis. Int J Mol Sci 2020; 21:ijms21155419. [PMID: 32751445 PMCID: PMC7432446 DOI: 10.3390/ijms21155419] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 07/26/2020] [Accepted: 07/28/2020] [Indexed: 01/12/2023] Open
Abstract
Terpene synthase (TPS) is a critical enzyme responsible for the biosynthesis of terpenes, which possess diverse roles in plant growth and development. Although many terpenes have been reported in orchids, limited information is available regarding the genome-wide identification and characterization of the TPS family in the orchid, Dendrobium officinale. By integrating the D. officinale genome and transcriptional data, 34 TPS genes were found in D. officinale. These were divided into four subfamilies (TPS-a, TPS-b, TPS-c, and TPS-e/f). Distinct tempospatial expression profiles of DoTPS genes were observed in 10 organs of D. officinale. Most DoTPS genes were predominantly expressed in flowers, followed by roots and stems. Expression of the majority of DoTPS genes was enhanced following exposure to cold and osmotic stresses. Recombinant DoTPS10 protein, located in chloroplasts, uniquely converted geranyl diphosphate to linalool in vitro. The DoTPS10 gene, which resulted in linalool formation, was highly expressed during all flower developmental stages. Methyl jasmonate significantly up-regulated DoTPS10 expression and linalool accumulation. These results simultaneously provide valuable insight into understanding the roles of the TPS family and lay a basis for further studies on the regulation of terpenoid biosynthesis by DoTPS in D. officinale.
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Affiliation(s)
- Zhenming Yu
- Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; (Z.Y.); (C.Z.); (G.Z.)
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Conghui Zhao
- Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; (Z.Y.); (C.Z.); (G.Z.)
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, China
| | - Guihua Zhang
- Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; (Z.Y.); (C.Z.); (G.Z.)
| | | | - Jun Duan
- Guangdong Provincial Key Laboratory of Applied Botany & Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China; (Z.Y.); (C.Z.); (G.Z.)
- Center of Economic Botany, Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou 510650, China
- Correspondence: ; Tel.: +86-020-37252978
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23
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Dimorphic flowers modify the visitation order of pollinators from male to female flowers. Sci Rep 2020; 10:9965. [PMID: 32561882 PMCID: PMC7305190 DOI: 10.1038/s41598-020-66525-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Accepted: 05/21/2020] [Indexed: 12/11/2022] Open
Abstract
Sexual dimorphism is a pervasive form of variation within species. Understanding how and why sexual dimorphism evolves would contribute to elucidating the mechanisms underlying the diversification of traits. In flowering plants, pollinators are considered a driver of sexual dimorphism when they affect female and male plant fitness in distinct ways. Here, we found that flowers appear to manipulate the behavior of pollinators using sexually dimorphic traits in the dioecious tree Eurya japonica. In this plant, female flowers present a higher-quality reward for pollinators, whereas male flowers have a more conspicuous appearance. Plants benefit by inducing pollinators to carry pollen from male to female flowers, and their sexual dimorphism might thus facilitate pollen movement through pollinator behavior. In two-choice experiments, pollinators frequently moved from male to female flowers, whereas computer simulation suggested that sexually dimorphic traits would evolve if pollinators changed behavior depending on the traits of the flowers they had just visited. These results suggest that the floral traits affecting the visiting order of pollinators have evolved in plants. Using E. japonica, we theoretically show that the induction of sequential behavior in pollinators might be crucial to the evolution of sexual dimorphism in flowers, and our experiments support these findings.
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24
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Hu R, Sun P, Yu H, Cheng Y, Wang R, Chen X, Kjellberg F. Similitudes and differences between two closely related Ficus species in the synthesis by the ostiole of odors attracting their host-specific pollinators: A transcriptomic based investigation. ACTA OECOLOGICA 2020. [DOI: 10.1016/j.actao.2020.103554] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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25
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Ueoka H, Sasaki K, Miyawaki T, Ichino T, Tatsumi K, Suzuki S, Yamamoto H, Sakurai N, Suzuki H, Shibata D, Yazaki K. A Cytosol-Localized Geranyl Diphosphate Synthase from Lithospermum erythrorhizon and Its Molecular Evolution. PLANT PHYSIOLOGY 2020; 182:1933-1945. [PMID: 31974127 PMCID: PMC7140919 DOI: 10.1104/pp.19.00999] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 12/22/2019] [Indexed: 05/23/2023]
Abstract
Geranyl diphosphate (GPP) is the direct precursor of all monoterpenoids and is the prenyl source of many meroterpenoids, such as geranylated coumarins. GPP synthase (GPPS) localized in plastids is responsible for providing the substrate for monoterpene synthases and prenyltransferases for synthesis of aromatic substances that are also present in plastids, but GPPS activity in Lithospermum erythrorhizon localizes to the cytosol, in which GPP is utilized for the biosynthesis of naphthoquinone pigments, which are shikonin derivatives. This study describes the identification of the cytosol-localized GPPS gene, LeGPPS, through EST- and homology-based approaches followed by functional analyses. The deduced amino acid sequence of the unique LeGPPS showed greater similarity to that of farnesyl diphosphate synthase (FPPS), which generally localizes to the cytosol, than to plastid-localized conventional GPPS. Biochemical characterization revealed that recombinant LeGPPS predominantly produces GPP along with a trace amount of FPP. LeGPPS expression was mainly detected in root bark, in which shikonin derivatives are produced, and in shikonin-producing cultured cells. The GFP fusion protein in onion (Allium cepa) cells localized to the cytosol. Site-directed mutagenesis of LeGPPS and another FPPS homolog identified in this study, LeFPPS1, showed that the His residue at position 100 of LeGPPS, adjacent to the first Asp-rich motif, contributes to substrate preference and product specificity, leading to GPP formation. These results suggest that LeGPPS, which is involved in shikonin biosynthesis, is recruited from cytosolic FPPS and that point mutation(s) result in the acquisition of GPPS activity.
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Affiliation(s)
- Hayato Ueoka
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji 611-0011, Japan
| | - Kanako Sasaki
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji 611-0011, Japan
| | - Tatsuya Miyawaki
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji 611-0011, Japan
| | - Takuji Ichino
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji 611-0011, Japan
| | - Kanade Tatsumi
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji 611-0011, Japan
| | - Shiro Suzuki
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji 611-0011, Japan
| | | | - Nozomu Sakurai
- Kazusa DNA Research Institute, Kisarazu, Chiba 292-0818, Japan
| | - Hideyuki Suzuki
- Kazusa DNA Research Institute, Kisarazu, Chiba 292-0818, Japan
| | - Daisuke Shibata
- Kazusa DNA Research Institute, Kisarazu, Chiba 292-0818, Japan
| | - Kazufumi Yazaki
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji 611-0011, Japan
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26
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Saryan P, Gowda V. Low-cost FloPump for regulated air sampling of volatile organic compounds. APPLICATIONS IN PLANT SCIENCES 2020; 8:e11343. [PMID: 32351802 PMCID: PMC7186897 DOI: 10.1002/aps3.11343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 03/04/2020] [Indexed: 06/11/2023]
Abstract
PREMISE We present a low-cost, battery-operated, portable pump, "FloPump," which allows regulated air sampling for the study of volatile organic compounds (VOCs). VOCs are routinely investigated in applications such as atmospheric chemistry, agriculture, and fragrance biology. METHODS AND RESULTS We compared the performance of FloPump with the Supelco pump in collecting VOCs using two test samples: guava fruit (Psidium guajava) and a perfume. The sampling and identification of volatiles was carried out using a dynamic headspace sampling method followed by gas chromatography-mass spectrometry. We show that the sampling efficiency of FloPump is comparable to the commercial pump, and at an affordable cost of ~US$115 (~86% cheaper), it provides a viable option for researchers interested in sampling volatiles on a constrained budget. CONCLUSIONS Accurate air sampling is critical for the study of VOCs. We propose that FloPump will make air sampling more affordable, thus encouraging studies of VOCs.
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Affiliation(s)
- Preeti Saryan
- Department of Biological SciencesIndian Institute of Science Education and Research BhopalBhopal Bypass RoadBhopalMadhya Pradesh462066India
| | - Vinita Gowda
- Department of Biological SciencesIndian Institute of Science Education and Research BhopalBhopal Bypass RoadBhopalMadhya Pradesh462066India
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Leiser-Miller LB, Kaliszewska ZA, Lauterbur ME, Mann B, Riffell JA, Santana SE. A Fruitful Endeavor: Scent Cues and Echolocation Behavior Used by Carollia castanea to Find Fruit. Integr Org Biol 2020; 2:obaa007. [PMID: 33791551 PMCID: PMC7671165 DOI: 10.1093/iob/obaa007] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Frugivores have evolved sensory and behavioral adaptations that allow them to find ripe fruit effectively, but the relative importance of different senses in varying foraging scenarios is still poorly understood. Within Neotropical ecosystems, short-tailed fruit bats (Carollia: Phyllostomidae) are abundant nocturnal frugivores that rely primarily on Piper fruits as a food resource. Previous research has demonstrated that Carollia employs olfaction and echolocation to locate Piper fruit, but it is unknown how their sensory use and foraging decisions are influenced by the complex diversity of chemical cues that fruiting plants produce. Using free-ranging C. castanea and their preferred food, Piper sancti-felicis, we conducted behavioral experiments to test two main hypotheses: (1) foraging decisions in C. castanea are primarily driven by ripe fruit scent and secondarily by vegetation scent, and (2) C. castanea re-weights their sensory inputs to account for available environmental cues, with bats relying more heavily on echolocation in the absence of adequate scent cues. Our results suggest that C. castanea requires olfactory information and relies almost exclusively on ripe fruit scent to make foraging attempts. Piper sancti-felicis ripe fruit scent is chemically distinct from vegetation scent; it is dominated by 2-heptanol, which is absent from vegetation scent, and has a greater abundance of β-caryophyllene, β-ocimene, γ-elemene, and α-cubebene. Although variation in echolocation call parameters was independent of scent cue presence, bats emitted longer and more frequent echolocation calls in trials where fruit scent was absent. Altogether, these results highlight the adaptations and plasticity of the sensory system in neotropical fruit bats.
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Affiliation(s)
- L B Leiser-Miller
- Department of Biology, University of Washington, Seattle, WA 98195, USA.,Burke Museum of Natural History and Culture, University of Washington, Seattle, WA 98195, USA
| | - Z A Kaliszewska
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - M E Lauterbur
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA
| | - Brianna Mann
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - J A Riffell
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - S E Santana
- Department of Biology, University of Washington, Seattle, WA 98195, USA.,Burke Museum of Natural History and Culture, University of Washington, Seattle, WA 98195, USA
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Ramya M, Jang S, An HR, Lee SY, Park PM, Park PH. Volatile Organic Compounds from Orchids: From Synthesis and Function to Gene Regulation. Int J Mol Sci 2020; 21:ijms21031160. [PMID: 32050562 PMCID: PMC7037033 DOI: 10.3390/ijms21031160] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/04/2020] [Accepted: 02/07/2020] [Indexed: 01/26/2023] Open
Abstract
Orchids are one of the most significant plants that have ecologically adapted to every habitat on earth. Orchids show a high level of variation in their floral morphologies, which makes them popular as ornamental plants in the global market. Floral scent and color are key traits for many floricultural crops. Volatile organic compounds (VOCs) play vital roles in pollinator attraction, defense, and interaction with the environment. Recent progress in omics technology has led to the isolation of genes encoding candidate enzymes responsible for the biosynthesis and regulatory circuits of plant VOCs. Uncovering the biosynthetic pathways and regulatory mechanisms underlying the production of floral scents is necessary not only for a better understanding of the function of relevant genes but also for the generation of new cultivars with desirable traits through molecular breeding approaches. However, little is known about the pathways responsible for floral scents in orchids because of their long life cycle as well as the complex and large genome; only partial terpenoid pathways have been reported in orchids. Here, we review the biosynthesis and regulation of floral volatile compounds in orchids. In particular, we focused on the genes responsible for volatile compounds in various tissues and developmental stages in Cymbidium orchids. We also described the emission of orchid floral volatiles and their function in pollination ecology. Taken together, this review will provide a broad scope for the study of orchid floral scents.
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Affiliation(s)
- Mummadireddy Ramya
- Floriculture Research Division, National Institute of Horticultural and Herbal Science, RDA, Wanju-gun, Jellabuk-do 55365, Korea; (M.R.); (H.-R.A.); (S.-Y.L.); (P.-M.P.)
| | - Seonghoe Jang
- World Vegetable Center Korea Office (WKO), Wanju-gun, Jellabuk-do 55365, Korea;
| | - Hye-Ryun An
- Floriculture Research Division, National Institute of Horticultural and Herbal Science, RDA, Wanju-gun, Jellabuk-do 55365, Korea; (M.R.); (H.-R.A.); (S.-Y.L.); (P.-M.P.)
| | - Su-Young Lee
- Floriculture Research Division, National Institute of Horticultural and Herbal Science, RDA, Wanju-gun, Jellabuk-do 55365, Korea; (M.R.); (H.-R.A.); (S.-Y.L.); (P.-M.P.)
| | - Pil-Man Park
- Floriculture Research Division, National Institute of Horticultural and Herbal Science, RDA, Wanju-gun, Jellabuk-do 55365, Korea; (M.R.); (H.-R.A.); (S.-Y.L.); (P.-M.P.)
| | - Pue Hee Park
- Floriculture Research Division, National Institute of Horticultural and Herbal Science, RDA, Wanju-gun, Jellabuk-do 55365, Korea; (M.R.); (H.-R.A.); (S.-Y.L.); (P.-M.P.)
- Department of Horticultural Science and Biotechnology, Seoul National University (SNU), Seoul 08826, Korea
- Correspondence: or ; Tel.: +82-10-4507-8321 or +82-63-238-6842; Fax: +82-63-238-6805
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Arnold SEJ, Forbes SJ, Hall DR, Farman DI, Bridgemohan P, Spinelli GR, Bray DP, Perry GB, Grey L, Belmain SR, Stevenson PC. Floral Odors and the Interaction between Pollinating Ceratopogonid Midges and Cacao. J Chem Ecol 2019; 45:869-878. [PMID: 31741191 DOI: 10.1007/s10886-019-01118-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 09/01/2019] [Accepted: 09/10/2019] [Indexed: 11/25/2022]
Abstract
Most plant species depend upon insect pollination services, including many cash and subsistence crops. Plants compete to attract those insects using visual cues and floral odor which pollinators associate with a reward. The cacao tree, Theobroma cacao, has a highly specialized floral morphology permitting pollination primarily by Ceratopogonid midges. However, these insects do not depend upon cacao flowers for their life cycle, and can use other sugar sources. To understand how floral cues mediate pollination in cacao we developed a method for rearing Ceratopogonidae through several complete lifecycles to provide material for bioassays. We carried out collection and analysis of cacao floral volatiles, and identified a bouquet made up exclusively of saturated and unsaturated, straight-chain hydrocarbons, which is unusual among floral odors. The most abundant components were tridecane, pentadecane, (Z)-7-pentadecene and (Z)-8-heptadecene with a heptadecadiene and heptadecatriene as minor components. We presented adult midges, Forcipomyia sp. (subgen. Forcipomyia), Culicoides paraensis and Dasyhelea borgmeieri, with natural and synthetic cacao flower odors in choice assays. Midges showed weak attraction to the complete natural floral odor in the assay, with no significant evidence of interspecific differences. This suggests that cacao floral volatiles play a role in pollinator behavior. Midges were not attracted to a synthetic blend of the above four major components of cacao flower odor, indicating that a more complete blend is required for attraction. Our findings indicate that cacao pollination is likely facilitated by the volatile blend released by flowers, and that the system involves a generalized odor response common to different species of Ceratopogonidae.
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Affiliation(s)
- Sarah E J Arnold
- Natural Resources Institute, University of Greenwich, Central Avenue, Chatham Maritime, Kent, ME4 4TB, UK.
| | - Samantha J Forbes
- Centre for Tropical Environmental and Sustainability Science, College of Science and Engineering, James Cook University, Cairns, Queensland, Australia
| | - David R Hall
- Natural Resources Institute, University of Greenwich, Central Avenue, Chatham Maritime, Kent, ME4 4TB, UK
| | - Dudley I Farman
- Natural Resources Institute, University of Greenwich, Central Avenue, Chatham Maritime, Kent, ME4 4TB, UK
| | - Puran Bridgemohan
- Biosciences, Agriculture and Food Technologies, University of Trinidad and Tobago, Caroni North Bank Road, Arima, Trinidad and Tobago
| | - Gustavo R Spinelli
- División Entomología, Museo de La Plata, Paseo del Bosque s/n, 1900, La Plata, Argentina
| | - Daniel P Bray
- Natural Resources Institute, University of Greenwich, Central Avenue, Chatham Maritime, Kent, ME4 4TB, UK
| | - Garvin B Perry
- Biosciences, Agriculture and Food Technologies, University of Trinidad and Tobago, Caroni North Bank Road, Arima, Trinidad and Tobago
| | - Leroy Grey
- Cocoa Industry Board of Jamaica, Marcus Garvey Drive, Kingston, Jamaica
| | - Steven R Belmain
- Natural Resources Institute, University of Greenwich, Central Avenue, Chatham Maritime, Kent, ME4 4TB, UK
| | - Philip C Stevenson
- Natural Resources Institute, University of Greenwich, Central Avenue, Chatham Maritime, Kent, ME4 4TB, UK
- Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AB, UK
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Jacquemart AL, Buyens C, Hérent MF, Quetin-Leclercq J, Lognay G, Hance T, Quinet M. Male flowers of Aconitum compensate for toxic pollen with increased floral signals and rewards for pollinators. Sci Rep 2019; 9:16498. [PMID: 31712605 PMCID: PMC6848206 DOI: 10.1038/s41598-019-53355-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 10/26/2019] [Indexed: 01/25/2023] Open
Abstract
Many plants require animal pollinators for successful reproduction; these plants provide pollinator resources in pollen and nectar (rewards) and attract pollinators by specific cues (signals). In a seeming contradiction, some plants produce toxins such as alkaloids in their pollen and nectar, protecting their resources from ineffective pollinators. We investigated signals and rewards in the toxic, protandrous bee-pollinated plant Aconitum napellus, hypothesizing that male-phase flower reproductive success is pollinator-limited, which should favour higher levels of signals (odours) and rewards (nectar and pollen) compared with female-phase flowers. Furthermore, we expected insect visitors to forage only for nectar, due to the toxicity of pollen. We demonstrated that male-phase flowers emitted more volatile molecules and produced higher volumes of nectar than female-phase flowers. Alkaloids in pollen functioned as chemical defences, and were more diverse and more concentrated compared to the alkaloids in nectar. Visitors actively collected little pollen for larval food but consumed more of the less-toxic nectar. Toxic pollen remaining on the bee bodies promoted pollen transfer efficiency, facilitating pollination.
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Affiliation(s)
- A-L Jacquemart
- Earth and Life Institute- Agronomy - Université catholique de Louvain, Croix du Sud 2, Box L7.05.14, B-1348, Louvain-la-Neuve, Belgium.
| | - C Buyens
- Earth and Life Institute- Agronomy - Université catholique de Louvain, Croix du Sud 2, Box L7.05.14, B-1348, Louvain-la-Neuve, Belgium
| | - M-F Hérent
- Louvain Drug Research Institute, Pharmacognosy Research Group - Université catholique de Louvain, Avenue E. Mounier, 72, B-1200, Brussels, Belgium
| | - J Quetin-Leclercq
- Louvain Drug Research Institute, Pharmacognosy Research Group - Université catholique de Louvain, Avenue E. Mounier, 72, B-1200, Brussels, Belgium
| | - G Lognay
- Analytical Chemistry, Gembloux Agro-Bio Tech, Université de Liège, Passage des Déportés 2, B-5030, Gembloux, Belgium
| | - T Hance
- Earth and Life Institute - Biodiversity - Université catholique de Louvain, Croix du Sud 4, Box L7.07.04, B-1348, Louvain-la-Neuve, Belgium
| | - M Quinet
- Earth and Life Institute- Agronomy - Université catholique de Louvain, Croix du Sud 2, Box L7.05.14, B-1348, Louvain-la-Neuve, Belgium
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Burkle LA, Runyon JB. Floral volatiles structure plant–pollinator interactions in a diverse community across the growing season. Funct Ecol 2019. [DOI: 10.1111/1365-2435.13424] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Laura A. Burkle
- Department of Ecology Montana State University Bozeman Montana
| | - Justin B. Runyon
- Rocky Mountain Research Station USDA Forest Service Bozeman Montana
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Barbosa-Cornelio R, Cantor F, Coy-Barrera E, Rodríguez D. Tools in the Investigation of Volatile Semiochemicals on Insects: From Sampling to Statistical Analysis. INSECTS 2019; 10:insects10080241. [PMID: 31390759 PMCID: PMC6723273 DOI: 10.3390/insects10080241] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/28/2019] [Accepted: 08/02/2019] [Indexed: 12/16/2022]
Abstract
The recognition of volatile organic compounds (VOCs) involved in insect interactions with plants or other organisms is essential for constructing a holistic comprehension of their role in ecology, from which the implementation of new strategies for pest and disease vector control as well as the systematic exploitation of pollinators and natural enemies can be developed. In the present paper, some of the general methods employed in this field are examined, focusing on their available technologies. An important part of the investigations conducted in this context begin with VOC collection directly from host organisms, using classical extraction methods, by the employment of adsorption materials used in solid-phase micro extraction (SPME) and direct-contact sorptive extraction (DCSE) and, subsequently, analysis through instrumental analysis techniques such as gas chromatography (GC), nuclear magnetic resonance (NMR) and mass spectrometry (MS), which provide crucial information for determining the chemical identity of volatile metabolites. Behavioral experiments, electroantennography (EAG), and biosensors are then carried out to define the semiochemicals with the best potential for performing relevant functions in ecological relationships. Chemical synthesis of biologically-active VOCs is alternatively performed to scale up the amount to be used in different purposes such as laboratory or field evaluations. Finally, the application of statistical analysis provides tools for drawing conclusions about the type of correlations existing between the diverse experimental variables and data matrices, thus generating models that simplify the interpretation of the biological roles of VOCs.
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Affiliation(s)
- Ricardo Barbosa-Cornelio
- Biological Control Laboratory, Facultad de Ciencias Básicas y Aplicadas, Universidad Militar Nueva Granada, Cajicá 250247, Colombia
- Bioorganic Chemistry Laboratory, Facultad de Ciencias Básicas y Aplicadas, Universidad Militar Nueva Granada, Cajicá 250247, Colombia
| | - Fernando Cantor
- Biological Control Laboratory, Facultad de Ciencias Básicas y Aplicadas, Universidad Militar Nueva Granada, Cajicá 250247, Colombia
| | - Ericsson Coy-Barrera
- Bioorganic Chemistry Laboratory, Facultad de Ciencias Básicas y Aplicadas, Universidad Militar Nueva Granada, Cajicá 250247, Colombia.
| | - Daniel Rodríguez
- Biological Control Laboratory, Facultad de Ciencias Básicas y Aplicadas, Universidad Militar Nueva Granada, Cajicá 250247, Colombia.
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Ramírez-Aguirre E, Martén-Rodríguez S, Quesada-Avila G, Quesada M, Martínez-Díaz Y, Oyama K, Espinosa-García FJ. Reproductive isolation among three sympatric Achimenes species: pre- and post-pollination components. AMERICAN JOURNAL OF BOTANY 2019; 106:1021-1031. [PMID: 31299090 DOI: 10.1002/ajb2.1324] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 05/06/2019] [Indexed: 06/10/2023]
Abstract
PREMISE Closely related species occurring in sympatry may experience the negative consequences of interspecific pollen transfer if reproductive isolation (RI) barriers are not in place. We evaluated the importance of pre- and post-pollination RI barriers in three sympatric species of Achimenes (Gesneriaceae), including ecogeographic, phenological, floral isolation, self-pollination, and hybrid viability (fruit and seed set). METHODS We recorded geographic distribution throughout species ranges and assessed flowering phenology and pollinator visitation at one site in central Mexico. In the greenhouse, we measured floral traits involved in RI and quantified fruit and seed set for from self, intraspecific, and interspecific crosses. RESULTS Ecogeographic barriers were important in RI, but under sympatry, phenological and floral barriers contributed more to total RI. Phenological RI varied between species and years, while floral RI was 100% effective at preventing interspecific visitation. Species showed differences in floral morphology, color, and scents associated with specialized pollination systems (A. antirrhina-hummingbirds, A. flava-bees, A. patens-butterflies); heterospecific visitation events were restricted to rare secondary pollinators. Hybrid crosses consistently yielded progeny in lower numbers than intraspecific crosses. CONCLUSIONS This study indicated that neither autogamy nor early post-pollination barriers prevent interspecific pollen flow between Achimenes species. However, floral isolation, acting through a combination of attraction and reward traits, consistently ensures specificity of the pollination system. These results suggest that selection on floral traits to reduce the costs of hybrid progeny production may have played a role in evolution or maintenance of specialized pollination systems in Achimenes.
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Affiliation(s)
- Erandi Ramírez-Aguirre
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE), Escuela Nacional de Estudios Superiores (ENES), Unidad Morelia, Universidad Nacional Autónoma de México, Morelia, Michoacán, C.P. 58190, México
- Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México. Unidad de Posgrado, Coordinación del Posgrado en Ciencias Biológicas. Edificio D, 1º Piso. Circuito de Posgrados, Ciudad Universitaria Del., Coyoacán, C. P. 04510, México D.F
| | - Silvana Martén-Rodríguez
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE), Escuela Nacional de Estudios Superiores (ENES), Unidad Morelia, Universidad Nacional Autónoma de México, Morelia, Michoacán, C.P. 58190, México
| | - Gabriela Quesada-Avila
- Universidad Nacional de Costa Rica, Heredia, Costa Rica. Avenida 1, Calle 9. Apartado Postal, 86-3000
| | - Mauricio Quesada
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE), Escuela Nacional de Estudios Superiores (ENES), Unidad Morelia, Universidad Nacional Autónoma de México, Morelia, Michoacán, C.P. 58190, México
- Instituto de Investigaciones en Ecosistemas, Universidad Nacional Autónoma de México, Antigua Carretera a Pátzcuaro 8701, Morelia, Michoacán, C.P. 58190, México
| | - Yesenia Martínez-Díaz
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE), Escuela Nacional de Estudios Superiores (ENES), Unidad Morelia, Universidad Nacional Autónoma de México, Morelia, Michoacán, C.P. 58190, México
| | - Ken Oyama
- Laboratorio Nacional de Análisis y Síntesis Ecológica (LANASE), Escuela Nacional de Estudios Superiores (ENES), Unidad Morelia, Universidad Nacional Autónoma de México, Morelia, Michoacán, C.P. 58190, México
| | - Francisco J Espinosa-García
- Instituto de Investigaciones en Ecosistemas, Universidad Nacional Autónoma de México, Antigua Carretera a Pátzcuaro 8701, Morelia, Michoacán, C.P. 58190, México
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Chapurlat E, Ågren J, Anderson J, Friberg M, Sletvold N. Conflicting selection on floral scent emission in the orchid Gymnadenia conopsea. THE NEW PHYTOLOGIST 2019; 222:2009-2022. [PMID: 30767233 DOI: 10.1111/nph.15747] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/04/2019] [Indexed: 06/09/2023]
Abstract
Floral scent is a crucial trait for pollinator attraction. Yet only a handful of studies have estimated selection on scent in natural populations and no study has quantified the relative importance of pollinators and other agents of selection. In the fragrant orchid Gymnadenia conopsea, we used electroantennographic data to identify floral scent compounds detected by local pollinators and quantified pollinator-mediated selection on emission rates of 10 target compounds as well as on flowering start, visual display and spur length. Nocturnal pollinators contributed more to reproductive success than diurnal pollinators, but there was significant pollinator-mediated selection on both diurnal and nocturnal scent emission. Pollinators selected for increased emission of two compounds and reduced emission of two other compounds, none of which were major constituents of the total bouquet. In three cases, pollinator-mediated selection was opposed by nonpollinator-mediated selection, leading to weaker or no detectable net selection. Our study demonstrates that minor scent compounds can be targets of selection, that pollinators do not necessarily favour stronger scent signalling, and that some scent compounds are subject to conflicting selection from pollinators and other agents of selection. Hence, including floral scent traits into selection analysis is important for understanding the mechanisms behind floral evolution.
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Affiliation(s)
- Elodie Chapurlat
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, 752 36, Uppsala, Sweden
| | - Jon Ågren
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, 752 36, Uppsala, Sweden
| | - Joseph Anderson
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, 752 36, Uppsala, Sweden
| | - Magne Friberg
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, 752 36, Uppsala, Sweden
- Department of Biology, Lund University, SE-223 62, Lund, Sweden
| | - Nina Sletvold
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, 752 36, Uppsala, Sweden
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Identification of Key Genes in the Synthesis Pathway of Volatile Terpenoids in Fruit of Zanthoxylum bungeanum Maxim. FORESTS 2019. [DOI: 10.3390/f10040328] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Zanthoxylum bungeanum Maxim. (Z. bungeanum), a plant that belongs to the Rutaceae family, is widely planted in China. Its outstanding feature is its rich aroma. The main component that creates this aroma is the volatile terpenoids. In this study, we aimed to understand the molecular mechanism related to aroma synthesis in Z. bungeanum and provide new ideas for breeding. Headspace solid phase micro extraction-gas chromatography mass spectrometry (HS-SPME-GC-MS), RT-qPCR and bioinformatics were used to study the changes in volatile terpenoids and identify key genes in the pathway of terpenoids in fruits of Z. bungeanum. The results show that the trend of volatile terpenoids is consistent among the two varieties. As the fruit matures, the terpenoids gradually accumulate and peak in the third period (mid-development) before gradually decreasing. Among these terpenoids, there is the highest content of α-pinene. In Z. bungeanum cv. ‘Hanchengdahongpao’ (Hanchengdahongpao) and Z. bungeanum cv. ‘Fuguhuajiao’ (Fuguhuajiao), this reached 24.74% and 20.78% respectively. In general, for the content of volatile terpenoids, Hanchengdahongpao is 62% and Fuguhuajiao is 41%. The results of RT-qPCR showed that most gene expression in this study was upregulated. Among them, ZbDXS has the highest relative level of expression in itself, which is the key rate-limiting enzymein the MEP pathway. These results explore the synthetic route of terpenoids during the ripening process of Z. bungeanum, which provides a reference for cultivar and improving good traits.
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Extreme diversification of floral volatiles within and among species of Lithophragma (Saxifragaceae). Proc Natl Acad Sci U S A 2019; 116:4406-4415. [PMID: 30765532 DOI: 10.1073/pnas.1809007116] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
A major challenge in evolutionary biology is to understand how complex traits of multiple functions have diversified and codiversified across interacting lineages and geographic ranges. We evaluate intra- and interspecific variation in floral scent, which is a complex trait of documented importance for mutualistic and antagonistic interactions between plants, pollinators, and herbivores. We performed a large-scale, phylogenetically structured study of an entire plant genus (Lithophragma, Saxifragaceae), of which several species are coevolving with specialized pollinating floral parasites of the moth genus Greya (Prodoxidae). We sampled 94 Lithophragma populations distributed across all 12 recognized Lithophragma species and subspecies, and four populations of related saxifragaceous species. Our results reveal an unusually high diversity of floral volatiles among populations, species, and clades within the genus. Moreover, we found unexpectedly major changes at each of these levels in the biosynthetic pathways used by local populations in their floral scents. Finally, we detected significant, but variable, genus- and species-level patterns of ecological convergence in the floral scent signal, including an impact of the presence and absence of two pollinating Greya moth species. We propose that one potential key to understanding floral scent variation in this hypervariable genus is its geographically diverse interactions with the obligate specialized Greya moths and, in some species and sites, more generalized copollinators.
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Wang TN, Clifford MR, Martínez-Gómez J, Johnson JC, Riffell JA, Di Stilio VS. Scent matters: differential contribution of scent to insect response in flowers with insect vs. wind pollination traits. ANNALS OF BOTANY 2019; 123:289-301. [PMID: 30052759 PMCID: PMC6344221 DOI: 10.1093/aob/mcy131] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 06/19/2018] [Indexed: 05/25/2023]
Abstract
BACKGROUND AND AIMS Growing experimental evidence that floral scent is a key contributor to pollinator attraction supports its investigation as a component of the suite of floral traits that result from pollinator-mediated selection. Yet, the fate of floral scent during the transition out of biotic into abiotic pollination has rarely been tested. In the case of wind pollination, this is due not only to its rarer incidence among flowering plants compared with insect pollination, but also to the scarcity of systems amenable to genus-level comparisons. Thalictrum (Ranunculaceae), with its multiple transitions from insect to wind pollination, offers a unique opportunity to test interspecific changes in floral fragrance and their potential impact on pollinator attraction. METHODS First, the Thalictrum phylogeny was revised and the ancestral character state of pollination mode was reconstructed. Then, volatile organic compounds (VOCs) that comprise the scent bouquets of flowers from 11 phylogenetically representative wind- and insect-pollinated species were characterized and compared. Finally, to test the hypothesis that scent from insect-pollinated flowers elicits a significantly greater response from potential pollinators than that from wind-pollinated flowers, electroantennograms (EAGs) were performed on Bombus impatiens using whole flower extracts. KEY RESULTS Phylogenetic reconstruction of the pollination mode recovered 8-10 transitions to wind pollination from an ancestral insect pollination state and two reversals to insect pollination. Biochemical and multivariate analysis showed that compounds are distinct by species and only partially segregate with pollination mode, with no significant phylogenetic signal on scent composition. Floral VOCs from insect-pollinated Thalictrum elicited a larger antennal response from potential insect pollinators than those from wind-pollinated congeners. CONCLUSIONS An evolutionary scenario is proposed where an ancestral ability of floral fragrance to elicit an insect response through the presence of specific compounds was independently lost during the multiple evolutionary transitions to wind pollination in Thalictrum.
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Affiliation(s)
- Theresa N Wang
- University of Washington, Department of Biology, Seattle, WA, USA
| | - Marie R Clifford
- University of Washington, Department of Biology, Seattle, WA, USA
| | - Jesús Martínez-Gómez
- University of Washington, Department of Biology, Seattle, WA, USA
- Department of Integrative Biology and University and Jepson Herbaria, University of California, Berkeley, CA, USA
| | - Jens C Johnson
- University of Washington, Department of Biology, Seattle, WA, USA
- Department of Geography, University of British Columbia, West Mall, Vancouver, British Columbia, Canada
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Haber AI, Sims JW, Mescher MC, De Moraes CM, Carr DE. A key floral scent component (β‐trans‐bergamotene) drives pollinator preferences independently of pollen rewards in seep monkeyflower. Funct Ecol 2018. [DOI: 10.1111/1365-2435.13246] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ariela I. Haber
- Department of Environmental Sciences University of Virginia Charlottesville Virginia
| | - James W. Sims
- Department of Environmental Systems Science ETH Zürich Zürich Switzerland
| | - Mark C. Mescher
- Department of Environmental Systems Science ETH Zürich Zürich Switzerland
| | | | - David E. Carr
- Blandy Experimental Farm University of Virginia Boyce Virginia
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Rering CC, Beck JJ, Hall GW, McCartney MM, Vannette RL. Nectar-inhabiting microorganisms influence nectar volatile composition and attractiveness to a generalist pollinator. THE NEW PHYTOLOGIST 2018; 220:750-759. [PMID: 28960308 DOI: 10.1111/nph.14809] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 08/21/2017] [Indexed: 05/18/2023]
Abstract
The plant microbiome can influence plant phenotype in diverse ways, yet microbial contribution to plant volatile phenotype remains poorly understood. We examine the presence of fungi and bacteria in the nectar of a coflowering plant community, characterize the volatiles produced by common nectar microbes and examine their influence on pollinator preference. Nectar was sampled for the presence of nectar-inhabiting microbes. We characterized the headspace of four common fungi and bacteria in a nectar analog. We examined electrophysiological and behavioral responses of honey bees to microbial volatiles. Floral headspace samples collected in the field were surveyed for the presence of microbial volatiles. Microbes commonly inhabit floral nectar and the common species differ in volatile profiles. Honey bees detected most microbial volatiles tested and distinguished among solutions based on volatiles only. Floral headspace samples contained microbial-associated volatiles, with 2-ethyl-1-hexanol and 2-nonanone - both detected by bees - more often detected when fungi were abundant. Nectar-inhabiting microorganisms produce volatile compounds, which can differentially affect honey bee preference. The yeast Metschnikowia reukaufii produced distinctive compounds and was the most attractive of all microbes compared. The variable presence of microbes may provide volatile cues that influence plant-pollinator interactions.
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Affiliation(s)
- Caitlin C Rering
- Chemistry Research Unit, Center for Medical, Agricultural and Veterinary Entomology, Agricultural Research Service, United States Department of Agriculture, 1700 SW 23rd Dr., Gainesville, FL, 32608, USA
| | - John J Beck
- Chemistry Research Unit, Center for Medical, Agricultural and Veterinary Entomology, Agricultural Research Service, United States Department of Agriculture, 1700 SW 23rd Dr., Gainesville, FL, 32608, USA
| | - Griffin W Hall
- Department of Entomology and Nematology, University of California, Davis, One Shields Ave., Davis, CA, 95616, USA
| | - Mitchell M McCartney
- Mechanical and Aerospace Engineering, University of California, Davis, One Shields Ave., Davis, CA, 95616, USA
| | - Rachel L Vannette
- Department of Entomology and Nematology, University of California, Davis, One Shields Ave., Davis, CA, 95616, USA
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40
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Glenny WR, Runyon JB, Burkle LA. Drought and increased CO 2 alter floral visual and olfactory traits with context-dependent effects on pollinator visitation. THE NEW PHYTOLOGIST 2018; 220:785-798. [PMID: 29575008 DOI: 10.1111/nph.15081] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 02/05/2018] [Indexed: 05/10/2023]
Abstract
Climate change can alter species interactions essential for maintaining biodiversity and ecosystem function, such as pollination. Understanding the interactive effects of multiple abiotic conditions on floral traits and pollinator visitation are important to anticipate the implications of climate change on pollinator services. Floral visual and olfactory traits were measured from individuals of four forb species subjected to drought or normal water availability, and elevated or ambient concentrations of CO2 in a factorial design. Pollinator visitation rates and community composition were observed in single-species and multi-species forb assemblages. Drought decreased floral visual traits and pollinator visitation rates but increased volatile organic compound (VOC) emissions, whereas elevated CO2 positively affected floral visual traits, VOC emissions and pollinator visitation rates. There was little evidence of interactive effects of drought and CO2 on floral traits and pollinator visitation. Interestingly, the effects of climate treatments on pollinator visitation depended on whether plants were in single- or multi-species assemblages. Components of climate change altered floral traits and pollinator visitation, but effects were modulated by plant community context. Investigating the response of floral traits, including VOCs, and context-dependency of pollinator attraction provides additional insights and may aid in understanding the overall effects of climate change on plant-pollinator interactions.
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Affiliation(s)
- William R Glenny
- Department of Ecology, Montana State University, Bozeman, MT, 59717, USA
| | - Justin B Runyon
- Rocky Mountain Research Station, USDA Forest Service, Bozeman, MT, 59717, USA
| | - Laura A Burkle
- Department of Ecology, Montana State University, Bozeman, MT, 59717, USA
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Startek JB, Voets T, Talavera K. To flourish or perish: evolutionary TRiPs into the sensory biology of plant-herbivore interactions. Pflugers Arch 2018; 471:213-236. [PMID: 30229297 DOI: 10.1007/s00424-018-2205-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 08/31/2018] [Accepted: 09/06/2018] [Indexed: 12/18/2022]
Abstract
The interactions between plants and their herbivores are highly complex systems generating on one side an extraordinary diversity of plant protection mechanisms and on the other side sophisticated consumer feeding strategies. Herbivores have evolved complex, integrative sensory systems that allow them to distinguish between food sources having mere bad flavors from the actually toxic ones. These systems are based on the senses of taste, olfaction and somatosensation in the oral and nasal cavities, and on post-ingestive chemosensory mechanisms. The potential ability of plant defensive chemical traits to induce tissue damage in foragers is mainly encoded in the latter through chemesthetic sensations such as burning, pain, itch, irritation, tingling, and numbness, all of which induce innate aversive behavioral responses. Here, we discuss the involvement of transient receptor potential (TRP) channels in the chemosensory mechanisms that are at the core of complex and fascinating plant-herbivore ecological networks. We review how "sensory" TRPs are activated by a myriad of plant-derived compounds, leading to cation influx, membrane depolarization, and excitation of sensory nerve fibers of the oronasal cavities in mammals and bitter-sensing cells in insects. We also illustrate how TRP channel expression patterns and functionalities vary between species, leading to intriguing evolutionary adaptations to the specific habitats and life cycles of individual organisms.
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Affiliation(s)
- Justyna B Startek
- Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, Campus Gasthuisberg O&N1 bus 802, 3000, Leuven, Belgium. .,VIB Center for Brain & Disease Research, Leuven, Belgium.
| | - Thomas Voets
- Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, Campus Gasthuisberg O&N1 bus 802, 3000, Leuven, Belgium.,VIB Center for Brain & Disease Research, Leuven, Belgium
| | - Karel Talavera
- Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49, Campus Gasthuisberg O&N1 bus 802, 3000, Leuven, Belgium.,VIB Center for Brain & Disease Research, Leuven, Belgium
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Lin T, Li C, Liu J, Smith BH, Lei H, Zeng X. Glomerular Organization in the Antennal Lobe of the Oriental Fruit Fly Bactrocera dorsalis. Front Neuroanat 2018; 12:71. [PMID: 30233333 PMCID: PMC6127620 DOI: 10.3389/fnana.2018.00071] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 08/06/2018] [Indexed: 11/30/2022] Open
Abstract
The oriental fruit fly, Bactrocera dorsalis is one of the most destructive pests of horticultural crops in tropical and subtropical Asia. The insect relies heavily on its olfactory system to select suitable hosts for development and reproduction. To understand the neural basis of its odor-driven behaviors, it is fundamental to characterize the anatomy of its olfactory system. In this study, we investigated the anatomical organization of the antennal lobe (AL), the primary olfactory center, in B. dorsalis, and constructed a 3D glomerular atlas of the AL based on synaptic antibody staining combined with computerized 3D reconstruction. To facilitate identification of individual glomeruli, we also applied mass staining of olfactory sensory neurons (OSNs) and projection neurons (PNs). In total, 64 or 65 glomeruli are identifiable in both sexes based on their shape, size, and relative spatial relationship. The overall glomerular volume of two sexes is not statistically different. However, eight glomeruli are sexually dimorphic: four (named AM2, C1, L2, and L3) are larger in males, and four are larger in females (A3, AD1, DM3, and M1). The results from anterograde staining, obtained by applying dye in the antennal lobe, show that three typical medial, media lateral, and lateral antennal-lobe tracts form parallel connections between the antennal lobe and protocerebrum. In addition to these three tracts, we also found a transverse antennal-lobe tract. Based on the retrograde staining of the calyx in the mushroom body, we also characterize the arrangement of roots and cell body clusters linked to the medial antennal-lobe tracts. These data provide a foundation for future studies on the olfactory processing of host odors in B. dorsalis.
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Affiliation(s)
- Tao Lin
- Guangdong Engineering Research Center for Insect Behavior Regulation, South China Agricultural University, Guangzhou, China
| | - Chaofeng Li
- Guangdong Engineering Research Center for Insect Behavior Regulation, South China Agricultural University, Guangzhou, China
| | - Jiali Liu
- Guangdong Engineering Research Center for Insect Behavior Regulation, South China Agricultural University, Guangzhou, China
| | - Brian H. Smith
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Hong Lei
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
| | - Xinnian Zeng
- Guangdong Engineering Research Center for Insect Behavior Regulation, South China Agricultural University, Guangzhou, China
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Chuang YC, Hung YC, Tsai WC, Chen WH, Chen HH. PbbHLH4 regulates floral monoterpene biosynthesis in Phalaenopsis orchids. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:4363-4377. [PMID: 29982590 PMCID: PMC6093345 DOI: 10.1093/jxb/ery246] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 06/20/2018] [Indexed: 05/22/2023]
Abstract
Floral scent is an important factor in attracting pollinators and repelling florivores. In Phalaenopsis bellina (Orchidaceae), the major floral scent components are monoterpenoids. Previously, we determined that expression of GERANYL DIPHOSPHATE SYNTHASE (PbGDPS) is highly correlated with monoterpene biosynthesis in Phalaenosis orchids. Here, we found that both cis- and trans-regulation were present on the GDPS promoters, with trans-regulation playing a key role. To investigate the regulation of biosynthesis of floral scent, we compared the transcriptomic data of two Phalaenopsis orchids with contrasting scent phenotypes. Eight transcription factors (TFs) that exhibited sequential elevation in abundance through floral development in P. bellina were identified, and their transcript levels were higher in the scented orchid than the scentless one. Five of these TFs transactivated several structural genes involved in monoterpene biosynthesis including PbbHLH4, PbbHLH6, PbbZIP4, PbERF1, and PbNAC1. Ectopic transient expression of each of these TFs in scentless orchids resulted in stimulation of terpenoid biosynthesis. PbbHLH4 most profoundly induced monoterpene biosynthesis, with a 950-fold increase of monoterpenoid production in the scentless orchid. In conclusion, we determined that biosynthesis of orchid floral monoterpenes was sequentially regulated, with PbbHLH4 playing a crucial role for monoterpene biosynthesis.
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Affiliation(s)
- Yu-Chen Chuang
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Yi-Chu Hung
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Chieh Tsai
- Institute of Tropical Plant Sciences, National Cheng Kung University, Tainan, Taiwan
- Orchid Research and Development Center, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Huei Chen
- Orchid Research and Development Center, National Cheng Kung University, Tainan, Taiwan
| | - Hong-Hwa Chen
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
- Institute of Tropical Plant Sciences, National Cheng Kung University, Tainan, Taiwan
- Orchid Research and Development Center, National Cheng Kung University, Tainan, Taiwan
- Correspondence:
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44
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Chuang YC, Hung YC, Tsai WC, Chen WH, Chen HH. PbbHLH4 regulates floral monoterpene biosynthesis in Phalaenopsis orchids. JOURNAL OF EXPERIMENTAL BOTANY 2018. [PMID: 29982590 DOI: 10.5061/dryad.kt056q7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Floral scent is an important factor in attracting pollinators and repelling florivores. In Phalaenopsis bellina (Orchidaceae), the major floral scent components are monoterpenoids. Previously, we determined that expression of GERANYL DIPHOSPHATE SYNTHASE (PbGDPS) is highly correlated with monoterpene biosynthesis in Phalaenosis orchids. Here, we found that both cis- and trans-regulation were present on the GDPS promoters, with trans-regulation playing a key role. To investigate the regulation of biosynthesis of floral scent, we compared the transcriptomic data of two Phalaenopsis orchids with contrasting scent phenotypes. Eight transcription factors (TFs) that exhibited sequential elevation in abundance through floral development in P. bellina were identified, and their transcript levels were higher in the scented orchid than the scentless one. Five of these TFs transactivated several structural genes involved in monoterpene biosynthesis including PbbHLH4, PbbHLH6, PbbZIP4, PbERF1, and PbNAC1. Ectopic transient expression of each of these TFs in scentless orchids resulted in stimulation of terpenoid biosynthesis. PbbHLH4 most profoundly induced monoterpene biosynthesis, with a 950-fold increase of monoterpenoid production in the scentless orchid. In conclusion, we determined that biosynthesis of orchid floral monoterpenes was sequentially regulated, with PbbHLH4 playing a crucial role for monoterpene biosynthesis.
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Affiliation(s)
- Yu-Chen Chuang
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Yi-Chu Hung
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Chieh Tsai
- Institute of Tropical Plant Sciences, National Cheng Kung University, Tainan, Taiwan
- Orchid Research and Development Center, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Huei Chen
- Orchid Research and Development Center, National Cheng Kung University, Tainan, Taiwan
| | - Hong-Hwa Chen
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
- Institute of Tropical Plant Sciences, National Cheng Kung University, Tainan, Taiwan
- Orchid Research and Development Center, National Cheng Kung University, Tainan, Taiwan
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45
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Crab spiders impact floral-signal evolution indirectly through removal of florivores. Nat Commun 2018; 9:1367. [PMID: 29636464 PMCID: PMC5893632 DOI: 10.1038/s41467-018-03792-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 03/13/2018] [Indexed: 02/05/2023] Open
Abstract
The puzzling diversity of flowers is primarily shaped by selection and evolutionary change caused by the plant's interaction with animals. The contribution of individual animal species to net selection, however, may vary depending on the network of interacting organisms. Here we document that in the buckler mustard, Biscutella laevigata, the crab spider Thomisus onustus reduces bee visits to flowers but also benefits plants by feeding on florivores. Uninfested plants experience a trade-off between pollinator and spider attraction as both bees and crab spiders are attracted by the floral volatile β-ocimene. This trade-off is reduced by the induced emission of β-ocimene after florivore infestation, which is stronger in plant populations where crab spiders are present than where they are absent, suggesting that plants are locally adapted to the presence of crab spiders. Our study demonstrates the context-dependence of selection and shows how crab spiders impact on floral evolution.
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Chapurlat E, Anderson J, Ågren J, Friberg M, Sletvold N. Diel pattern of floral scent emission matches the relative importance of diurnal and nocturnal pollinators in populations of Gymnadenia conopsea. ANNALS OF BOTANY 2018; 121:711-721. [PMID: 29360931 PMCID: PMC5853007 DOI: 10.1093/aob/mcx203] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
BACKGROUND AND AIMS Floral scent is considered an integral component of pollination syndromes, and its composition and timing of emission are thus expected to match the main pollinator type and time of activity. While floral scent differences among plant species with different pollination systems can be striking, studies on intraspecific variation are sparse, which limits our understanding of the role of pollinators in driving scent divergence. METHODS Here, we used dynamic headspace sampling to quantify floral scent emission and composition during the day and at night in the natural habitat of six Scandinavian populations of the fragrant orchid Gymnadenia conopsea. We tested whether diel scent emission and composition match pollinator type by comparing four populations in southern Sweden, where nocturnal pollinators are more important for plant reproductive success than are diurnal pollinators, with two populations in central Norway, where the opposite is true. To determine to what extent scent patterns quantified in the field reflected plasticity, we also measured scent emission in a common growth chamber environment. KEY RESULTS Both scent composition and emission rates differed markedly between day and night, but only the latter varied significantly among populations. The increase in scent emission rate at night was considerably stronger in the Swedish populations compared with the Norwegian populations. These patterns persisted when plants were transferred to a common environment, suggesting a genetic underpinning of the scent variation. CONCLUSIONS The results are consistent with a scenario where spatial variation in relative importance of nocturnal and diurnal pollinators has resulted in selection for different scent emission rhythms. Our study highlights the importance of adding a characterization of diel variation of scent emission rates to comparative studies of floral scent, which so far have often focused on scent composition only.
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Affiliation(s)
- Elodie Chapurlat
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen, Sweden
- For correspondence. E-mail
| | - Joseph Anderson
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen, Sweden
| | - Jon Ågren
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen, Sweden
| | - Magne Friberg
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen, Sweden
| | - Nina Sletvold
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen, Sweden
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Abstract
Pollinator-mediated selection on plants can favor transitions to a new pollinator depending on the relative abundances and efficiencies of pollinators present in the community. A frequently observed example is the transition from bee pollination to hummingbird pollination. We present a population genetic model that examines whether the ability to inbreed can influence evolutionary change in traits that underlie pollinator attraction. We find that a transition to a more efficient but less abundant pollinator is favored under a broadened set of ecological conditions if plants are capable of delayed selfing rather than obligately outcrossing. Delayed selfing allows plants carrying an allele that attracts the novel pollinator to reproduce even when this pollinator is rare, providing reproductive assurance. In addition, delayed selfing weakens the effects of Haldane's sieve by increasing the fixation probability for recessive alleles that confer adaptation to the new pollinator. Our model provides novel insight into the paradoxical abundance of recessive mutations in adaptation to hummingbird attraction. It further predicts that transitions to efficient but less abundant pollinators (such as hummingbirds in certain communities) should disproportionately occur in self-compatible lineages. Currently available mating system data sets are consistent with this prediction, and we suggest future areas of research that will enable a rigorous test of this theory.
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Chuang YC, Hung YC, Hsu CY, Yeh CM, Mitsuda N, Ohme-Takagi M, Tsai WC, Chen WH, Chen HH. A Dual Repeat Cis-Element Determines Expression of GERANYL DIPHOSPHATE SYNTHASE for Monoterpene Production in Phalaenopsis Orchids. FRONTIERS IN PLANT SCIENCE 2018; 9:765. [PMID: 29922327 PMCID: PMC5996158 DOI: 10.3389/fpls.2018.00765] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 05/17/2018] [Indexed: 05/05/2023]
Abstract
Phalaenopsis bellina is a scented orchid emitting large amount of monoterpenes. GERANYL DIPHOSPHATE SYNTHASE (PbGDPS) is the key enzyme for monoterpene biosynthesis, and shows concomitant expression with the emission of monoterpenes during flower development in P. bellina. Here, we identified a dual repeat cis-element in the GDPS promoter that is critical for monoterpene biosynthesis in Phalaenopsis orchids. A strong correlation between the dual repeat and the monoterpene production was revealed by examination of the GDPS promoter fragments over 12 Phalaenopsis species. Serial-deletion of the 2-kb GDPS promoter fragments demonstrated that the integrity of the dual repeat was crucial for its promoter activities. By screening the Arabidopsis transcription factors (TFs) cDNA library using yeast one-hybrid assay, AtbZIP18, a member of group I of bZIP TFs, was identified to be able to bind the dual repeat. We then identified PbbZIP4 in the transcriptome of P. bellina, showing 83% identity in the DNA binding region with that of AtbZIP18, and the expression level of PbbZIP4 was higher in the scented orchids. In addition, PbbZIP4 transactivated the GDPS promoter fragment containing the dual repeat in dual luciferase assay. Furthermore, transient ectopic expression of PbbZIP4 induced a 10-fold production of monoterpenoids in the scentless orchid. In conclusion, these results indicate that the dual repeat is a real TF-bound cis-element significant for GDPS gene expression, and thus subsequent monoterpene biosynthesis in the scented Phalaenopsis orchids.
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Affiliation(s)
- Yu-Chen Chuang
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Yi-Chu Hung
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Chi-Yu Hsu
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Chuan-Ming Yeh
- Division of Strategic Research and Development, Graduate School of Science and Engineering, Saitama University, Saitama, Japan
| | - Nobutaka Mitsuda
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
| | - Masaru Ohme-Takagi
- Division of Strategic Research and Development, Graduate School of Science and Engineering, Saitama University, Saitama, Japan
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
| | - Wen-Chieh Tsai
- Institute of Tropical Plant Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Wen-Huei Chen
- Orchid Research and Development Center, National Cheng Kung University, Tainan, Taiwan
| | - Hong-Hwa Chen
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
- Institute of Tropical Plant Sciences, National Cheng Kung University, Tainan, Taiwan
- Orchid Research and Development Center, National Cheng Kung University, Tainan, Taiwan
- *Correspondence: Hong-Hwa Chen,
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Telles FJ, Corcobado G, Trillo A, Rodríguez-Gironés MA. Multimodal cues provide redundant information for bumblebees when the stimulus is visually salient, but facilitate red target detection in a naturalistic background. PLoS One 2017; 12:e0184760. [PMID: 28898287 PMCID: PMC5595325 DOI: 10.1371/journal.pone.0184760] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 08/30/2017] [Indexed: 12/22/2022] Open
Abstract
Our understanding of how floral visitors integrate visual and olfactory cues when seeking food, and how background complexity affects flower detection is limited. Here, we aimed to understand the use of visual and olfactory information for bumblebees (Bombus terrestris terrestris L.) when seeking flowers in a visually complex background. To explore this issue, we first evaluated the effect of flower colour (red and blue), size (8, 16 and 32 mm), scent (presence or absence) and the amount of training on the foraging strategy of bumblebees (accuracy, search time and flight behaviour), considering the visual complexity of our background, to later explore whether experienced bumblebees, previously trained in the presence of scent, can recall and make use of odour information when foraging in the presence of novel visual stimuli carrying a familiar scent. Of all the variables analysed, flower colour had the strongest effect on the foraging strategy. Bumblebees searching for blue flowers were more accurate, flew faster, followed more direct paths between flowers and needed less time to find them, than bumblebees searching for red flowers. In turn, training and the presence of odour helped bees to find inconspicuous (red) flowers. When bees foraged on red flowers, search time increased with flower size; but search time was independent of flower size when bees foraged on blue flowers. Previous experience with floral scent enhances the capacity of detection of a novel colour carrying a familiar scent, probably by elemental association influencing attention.
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Affiliation(s)
- Francismeire Jane Telles
- Department of Functional and Evolutionary Ecology, Estación Experimental de Zonas Áridas (EEZA-CSIC), Almería, Spain
- * E-mail:
| | | | - Alejandro Trillo
- Department of Integrative Ecology, Doñana Biological Station, Sevilla, Spain
| | - Miguel A. Rodríguez-Gironés
- Department of Functional and Evolutionary Ecology, Estación Experimental de Zonas Áridas (EEZA-CSIC), Almería, Spain
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Ruiz-Hernández V, Hermans B, Weiss J, Egea-Cortines M. Genetic Analysis of Natural Variation in Antirrhinum Scent Profiles Identifies BENZOIC ACID CARBOXYMETHYL TRANSFERASE As the Major Locus Controlling Methyl Benzoate Synthesis. FRONTIERS IN PLANT SCIENCE 2017; 8:27. [PMID: 28154577 PMCID: PMC5244254 DOI: 10.3389/fpls.2017.00027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 01/05/2017] [Indexed: 05/31/2023]
Abstract
The Antirrhinum genus has a considerable complexity in the scent profiles produced by different species. We have analyzed the genetic differences between A. majus and A. linkianum, two species divergent in the emission of methyl benzoate, methyl cinnamate, acetophenone, and ocimene. The genetic analysis showed that all compounds segregated in a Mendelian fashion attributable to one or two loci with simple or epistatic interactions. Several lines lacked methyl benzoate, a major Volatile Organic Compound emitted by A. majus but missing in A. linkianum. Using a candidate gene approach, we found that the BENZOIC ACID CARBOXYMETHYL TRANSFERASE from A. linkianum appeared to be a null allele as we could not detect mRNA expression. The coding region did not show significant differences that could explain the loss of expression. The intron-exon boundaries was also conserved indicating that there is no alternative splicing in A. linkianum as compared to A. majus. However, it showed multiple polymorphisms in the 5' promoter region including two insertions, one harboring an IDLE MITE transposon with additional sequences with high homology to the PLENA locus and a second one with somewhat lower homology to the regulatory region of the VENOSA locus. It also had a 778 bp deletion as compared to the A. majus BAMT promoter region. Our results show that the differences in scent emission between A. majus and A. linkianum may be traced back to single genes involved in discrete biosynthetic reactions such as benzoic acid methylation. Thus, natural variation of this complex trait maybe the result of combinations of wild type, and loss of function alleles in different genes involved in discrete VOCs biosynthesis. Furthermore, the presence of active transposable elements in the genus may account for rapid evolution and instability, raising the possibility of adaptation to local pollinators.
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