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Grierson ERP, Thrimawithana AH, van Klink JW, Lewis DH, Carvajal I, Shiller J, Miller P, Deroles SC, Clearwater MJ, Davies KM, Chagné D, Schwinn KE. A phosphatase gene is linked to nectar dihydroxyacetone accumulation in mānuka (Leptospermum scoparium). THE NEW PHYTOLOGIST 2024. [PMID: 38532557 DOI: 10.1111/nph.19714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 03/06/2024] [Indexed: 03/28/2024]
Abstract
Floral nectar composition beyond common sugars shows great diversity but contributing genetic factors are generally unknown. Mānuka (Leptospermum scoparium) is renowned for the antimicrobial compound methylglyoxal in its derived honey, which originates from the precursor, dihydroxyacetone (DHA), accumulating in the nectar. Although this nectar trait is highly variable, genetic contribution to the trait is unclear. Therefore, we investigated key gene(s) and genomic regions underpinning this trait. We used RNAseq analysis to identify nectary-associated genes differentially expressed between high and low nectar DHA genotypes. We also used a mānuka high-density linkage map and quantitative trait loci (QTL) mapping population, supported by an improved genome assembly, to reveal genetic regions associated with nectar DHA content. Expression and QTL analyses both pointed to the involvement of a phosphatase gene, LsSgpp2. The expression pattern of LsSgpp2 correlated with nectar DHA accumulation, and it co-located with a QTL on chromosome 4. The identification of three QTLs, some of the first reported for a plant nectar trait, indicates polygenic control of DHA content. We have established plant genetics as a key influence on DHA accumulation. The data suggest the hypothesis of LsSGPP2 releasing DHA from DHA-phosphate and variability in LsSgpp2 gene expression contributing to the trait variability.
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Affiliation(s)
- Ella R P Grierson
- The New Zealand Institute for Plant and Food Research Limited (PFR), Palmerston North, 4472, New Zealand
- Te Aka Mātuatua - School of Science, University of Waikato, Hamilton, 3216, New Zealand
| | | | - John W van Klink
- PFR, Chemistry Department, University of Otago, Dunedin, 9016, New Zealand
| | - David H Lewis
- The New Zealand Institute for Plant and Food Research Limited (PFR), Palmerston North, 4472, New Zealand
| | | | - Jason Shiller
- PFR, Te Puke Research Centre, Te Puke, 3182, New Zealand
| | - Poppy Miller
- PFR, Te Puke Research Centre, Te Puke, 3182, New Zealand
| | | | - Michael J Clearwater
- Te Aka Mātuatua - School of Science, University of Waikato, Hamilton, 3216, New Zealand
| | - Kevin M Davies
- The New Zealand Institute for Plant and Food Research Limited (PFR), Palmerston North, 4472, New Zealand
| | - David Chagné
- The New Zealand Institute for Plant and Food Research Limited (PFR), Palmerston North, 4472, New Zealand
| | - Kathy E Schwinn
- The New Zealand Institute for Plant and Food Research Limited (PFR), Palmerston North, 4472, New Zealand
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2
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Kidyoo A, Kidyoo M, Ekkaphan P, Blatrix R, McKey D, Proffit M. Specialized pollination by cecidomyiid flies and associated floral traits in Vincetoxicum sangyojarniae (Apocynaceae, Asclepiadoideae). PLANT BIOLOGY (STUTTGART, GERMANY) 2024; 26:166-180. [PMID: 38196297 DOI: 10.1111/plb.13607] [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: 06/08/2023] [Accepted: 11/27/2023] [Indexed: 01/11/2024]
Abstract
Specialized pollination systems frequently match a particular set of floral characteristics. Vincetoxicum spp. (Apocynaceae, Asclepiadoideae) have disk-shaped flowers with open access to rewards and reproductive organs. Flowers with these traits are usually associated with generalized pollination. However, the highly modified androecium and gynoecium that characterize asclepiads are thought to be associated with specialized pollinators. In V. sangyojarniae, we investigated floral biology, pollination, and the degree of pollinator specialization in two localities in Thailand. We examined floral traits that target legitimate pollinators. Flowers of V. sangyojarniae opened only at night, emitted floral scents containing mainly (E)-β-ocimene, 1-octen-3-ol, (E)-4,8-dimethyl-1,3,7-nonatriene (E-DMNT) and N-(3-methylbutyl)acetamide, and provided sucrose-dominated nectar openly to insect visitors. Assessment of pollinator effectiveness indicated that V. sangyojarniae is functionally specialized for pollination by cecidomyiid flies. Although various insects, particularly cockroaches, frequently visited flowers, they did not carry pollinaria. Our results suggest that V. sangyojarniae attracts its fly pollinators by emitting floral volatiles bearing olfactory notes associated with the presence of fungi or, less likely, of prey captured by predatory arthropods (food sources of its pollinators) but offers a nectar reward upon insect arrival. Hence, there is a mismatch between the advertisement and the actual reward. Our results also suggest that the size of floral parts constitutes a mechanical filter where reciprocal fit between flower and insect structures ensures that only suitable pollinators can extract the pollinaria, a prerequisite for successful pollination.
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Affiliation(s)
- A Kidyoo
- Plants of Thailand Research Unit, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - M Kidyoo
- Plants of Thailand Research Unit, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
| | - P Ekkaphan
- Scientific and Technological Research Equipment Centre, Chulalongkorn University, Bangkok, Thailand
| | - R Blatrix
- CEFE, University of Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - D McKey
- CEFE, University of Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - M Proffit
- CEFE, University of Montpellier, CNRS, EPHE, IRD, Montpellier, France
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3
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Quarrell S, Weinstein AM, Hannah L, Bonavia N, del Borrello O, Flematti GR, Bohman B. Critical Pollination Chemistry: Specific Sesquiterpene Floral Volatiles in Carrot Inhibit Honey Bee Feeding. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:16079-16089. [PMID: 37871312 PMCID: PMC10623568 DOI: 10.1021/acs.jafc.3c03392] [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: 05/23/2023] [Revised: 08/22/2023] [Accepted: 10/10/2023] [Indexed: 10/25/2023]
Abstract
Many plants rely on insect pollination, yet numerous agricultural plant-breeding programs focus on traits that appeal to growers and consumers instead of pollinators, leading to declining pollinator attraction and crop yields. Using hybrid carrot seed production as a model, we investigated low-yielding carrot varieties by analyzing sugars and minerals in nectar and floral volatile composition. While the analysis of nectar sugars and minerals did not reveal any key differences between the carrot varieties, differences between the 112 detected volatiles in 23 samples were observed. Numerous differentiating sesquiterpenes were identified in floral solvent extracts, and subsequent behavioral assays showed that β-ocimene from higher-yielding carrot varieties stimulated nectar feeding (attractant), while α- and β-selinene from lower-yielding lines decreased feeding (deterrents). Sesquiterpenes have previously been implicated in plant defense, suggesting a trade-off between pollination and protection. Our results highlight the importance of volatiles as regulators of pollinator attraction in agricultural settings.
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Affiliation(s)
- Stephen
R. Quarrell
- Tasmanian
Institute of Agriculture, University of
Tasmania, College Rd, Hobart 7005, Australia
| | - Alyssa M. Weinstein
- Ecology
and Evolution, Research School of Biology, The Australian National University, Canberra 2601, Australia
| | - Lea Hannah
- Seed
Production Research, Research and Development, Rijk Zwaan Australia, Musk, Victoria 3461, Australia
- Hawkesbury
Institute for the Environment, Western Sydney
University, Richmond, New South Wales 2753, Australia
| | - Nicole Bonavia
- Seed
Production Research, Research and Development, Rijk Zwaan Australia, Musk, Victoria 3461, Australia
| | - Oscar del Borrello
- School
of Molecular Sciences, University of Western
Australia, Crawley, Western Australia 6009, Australia
| | - Gavin R. Flematti
- School
of Molecular Sciences, University of Western
Australia, Crawley, Western Australia 6009, Australia
| | - Björn Bohman
- School
of Molecular Sciences, University of Western
Australia, Crawley, Western Australia 6009, Australia
- Department
of Plant Protection Biology, Swedish University
of Agricultural Sciences, Lomma 234 22, Sweden
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4
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Voß AC, Hauertmann M, Laufer MC, Lach A, Junker RR, Eilers EJ. Fungicides and strawberry pollination-Effects on floral scent, pollen attributes and bumblebee behavior. PLoS One 2023; 18:e0289283. [PMID: 37498837 PMCID: PMC10374001 DOI: 10.1371/journal.pone.0289283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 07/14/2023] [Indexed: 07/29/2023] Open
Abstract
Fungicides are used in agriculture to protect crops from various fungal diseases. However, they may modulate the plants metabolism. Moreover, fungicides can accumulate in the environment and may cause toxic effects on non-target organisms such as nectar microbes and pollinators. Nectar microbes contribute to the volatile profile of flowers and can influence pollinators behaviour. Thus, fungicide treatment could potentially affect the pollination. In this study, we investigated the influence of fungicide treatment on floral attributes as well as the behavioural impact on bumblebees. In separate experiments, we used one or both strawberry cultivars (Fragaria × ananassa var. Darselect and Malwina), which were either kept untreated (control) or treated with either Cuprozin® progress or SWITCH® fungicide. We analysed various flower traits including volatiles, pollen weight, pollen protein, and the attraction of bumblebees towards the flowers in the greenhouse. Additionally, we analysed the viability of pollen and pollen live-to-dead ratio, as well as the composition of nectar fungi in the field. A treatment with Cuprozin® progress led to a lower emission of floral volatiles and a slightly lower pollen protein content. This had no impact on the visit latency of bumblebees but on the overall visit frequency of these flowers. The treatment with the fungicide SWITCH® resulted in a higher emission of floral volatiles as well as a delayed first visit by bumblebees. Furthermore, flowers of control plants were visited more often than those treated with the two fungicides. Plant-pollinator interactions are highly complex, with many contributing factors. Fungicides can have an impact on the pollen quality and pollinator attraction, potentially leading to an altered pollen dispersal by pollinators and a change in fruit quality.
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Affiliation(s)
- Ann-Cathrin Voß
- Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany
| | | | | | - Alexander Lach
- Evolutionary Ecology of Plants, Philipps-University Marburg, Marburg, Germany
| | - Robert R Junker
- Evolutionary Ecology of Plants, Philipps-University Marburg, Marburg, Germany
| | - Elisabeth J Eilers
- Department of Chemical Ecology, Bielefeld University, Bielefeld, Germany
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Obeng-Darko SA, Sloan J, Binks RM, Brooks PR, Veneklaas EJ, Finnegan PM. Dihydroxyacetone in the Floral Nectar of Ericomyrtus serpyllifolia (Turcz.) Rye (Myrtaceae) and Verticordia chrysantha Endl. (Myrtaceae) Demonstrates That This Precursor to Bioactive Honey Is Not Restricted to the Genus Leptospermum (Myrtaceae). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:7703-7709. [PMID: 37191313 DOI: 10.1021/acs.jafc.3c00673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Ma̅nuka honey is known for its strong bioactivity, which arises from the autocatalytic conversion of 1,3-dihydroxyacetone (dihydroxyacetone, DHA) in the floral nectar of Leptospermum scoparium (Myrtaceae) to the non-peroxide antibacterial compound methylglyoxal during honey maturation. DHA is also a minor constituent of the nectar of several other Leptospermum species. This study used high-performance liquid chromatography to test whether DHA was present in the floral nectar of five species in other genera of the family Myrtaceae: Ericomyrtus serpyllifolia (Turcz.) Rye, Chamelaucium sp. Bendering (T.J. Alford 110), Kunzea pulchella (Lindl.) A.S. George, Verticordia chrysantha Endl., and Verticordia picta Endl. DHA was found in the floral nectar of two of the five species: E. serpyllifolia and V. chrysantha. The average amount of DHA detected was 0.08 and 0.64 μg per flower, respectively. These findings suggest that the accumulation of DHA in floral nectar is a shared trait among several genera within the family Myrtaceae. Consequently, non-peroxide-based bioactive honey may be sourced from floral nectar outside the genus Leptospermum.
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Affiliation(s)
- Sylvester A Obeng-Darko
- School of Biological Sciences, The University of Western Australia, Perth, Western Australia 6009, Australia
- CRC for Honey Bee Products, 128 Yanchep Beach Road, Yanchep 6035, Australia
| | - Jean Sloan
- CRC for Honey Bee Products, 128 Yanchep Beach Road, Yanchep 6035, Australia
| | - Rachel M Binks
- School of Biological Sciences, The University of Western Australia, Perth, Western Australia 6009, Australia
- CRC for Honey Bee Products, 128 Yanchep Beach Road, Yanchep 6035, Australia
- Department of Biodiversity, Conservation and Attractions, Biodiversity and Conservation Science, Locked Bag 104, Bentley Delivery Centre, Bentley, Western Australia 6983, Australia
| | - Peter R Brooks
- CRC for Honey Bee Products, 128 Yanchep Beach Road, Yanchep 6035, Australia
- School of Sciences, Technology and Engineering, University of the Sunshine Coast, Maroochydore, Queensland 4558, Australia
| | - Erik J Veneklaas
- School of Biological Sciences, The University of Western Australia, Perth, Western Australia 6009, Australia
| | - Patrick M Finnegan
- School of Biological Sciences, The University of Western Australia, Perth, Western Australia 6009, Australia
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6
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Carey S, Zenchyzen B, Deneka AJ, Hall JC. Nectary development in Cleome violacea. FRONTIERS IN PLANT SCIENCE 2023; 13:1085900. [PMID: 36844906 PMCID: PMC9949531 DOI: 10.3389/fpls.2022.1085900] [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: 10/31/2022] [Accepted: 12/22/2022] [Indexed: 06/18/2023]
Abstract
Nectaries are a promising frontier for plant evo-devo research, and are particularly fascinating given their diversity in form, position, and secretion methods across angiosperms. Emerging model systems permit investigations of the molecular basis for nectary development and nectar secretion across a range of taxa, which addresses fundamental questions about underlying parallelisms and convergence. Herein, we explore nectary development and nectar secretion in the emerging model taxa, Cleome violacea (Cleomaceae), which exhibits a prominent adaxial nectary. First, we characterized nectary anatomy and quantified nectar secretion to establish a foundation for quantitative and functional gene experiments. Next, we leveraged RNA-seq to establish gene expression profiles of nectaries across three key stages of development: pre-anthesis, anthesis, and post-fertilization. We then performed functional studies on five genes that were putatively involved in nectary and nectar formation: CvCRABSCLAW (CvCRC), CvAGAMOUS (CvAG), CvSHATTERPROOF (CvSHP), CvSWEET9, and a highly expressed but uncharacterized transcript. These experiments revealed a high degree of functional convergence to homologues from other core Eudicots, especially Arabidopsis. CvCRC, redundantly with CvAG and CvSHP, are required for nectary initiation. Concordantly, CvSWEET9 is essential for nectar formation and secretion, which indicates that the process is eccrine based in C. violacea. While demonstration of conservation is informative to our understanding of nectary evolution, questions remain. For example, it is unknown which genes are downstream of the developmental initiators CvCRC, CvAG, and CvSHP, or what role the TCP gene family plays in nectary initiation in this family. Further to this, we have initiated a characterization of associations between nectaries, yeast, and bacteria, but more research is required beyond establishing their presence. Cleome violacea is an excellent model for continued research into nectary development because of its conspicuous nectaries, short generation time, and close taxonomic distance to Arabidopsis.
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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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Bergonzoli S, Romano E, Beni C, Latterini F, Lo Scalzo R, Scarfone A. Nectar Dynamics and Pollinators Preference in Sunflower. INSECTS 2022; 13:717. [PMID: 36005342 PMCID: PMC9409638 DOI: 10.3390/insects13080717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/04/2022] [Accepted: 08/07/2022] [Indexed: 06/15/2023]
Abstract
Nectar is a complex biochemical substance secreted with particular rhythm by flower nectaries. Nectar is the base of a mutualism in which pollinators consume nectar, as food source, and are involuntarily responsible for the transport of pollen and pollination. The dynamics and temporal patterns of nectar secretion are still not fully understood as well as the environmental and climatic factors influencing its production. The quantity and quality of nectar found in standing crops at flowering influence the mutualistic relationship with pollinators and their foraging behavior. This situation is even more significant considering the reduction in undisturbed environments, the loss of soil quality, the spread of monoculture agricultural management and the use of self-fertile hybrids. The objects of the study are understanding the relationship among soil properties and nectar quality, comparing the nectar composition in a sunflower hybrid variety and evaluate pollinator preferences in selecting nectar sources among hybrid and non-hybrid varieties. For these purposes, two different experimental tests were established. Results highlighted that fertilization strategy influenced crop biomass development, determined soil characteristics and nectar composition in Sunflower. However, when comparing nectar composition of hybrid and non-hybrid varieties of sunflower, no significant differences were found. Despite this, the analysis of number of visits on the two treatments showed statistically significant differences. This research provides further understanding of the very complex relationship among soil, crop and nectar to support the definition of agricultural management strategies and reach the optimal nectar composition level for pollinators in agricultural crops.
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Affiliation(s)
- Simone Bergonzoli
- Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria (CREA), Centro di Ricerca Ingegneria e Trasformazioni Agroalimentari, Via della Pascolare 15, 00015 Monterotondo, Italy
| | - Elio Romano
- Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria (CREA), Centro di Ricerca Ingegneria e Trasformazioni Agroalimentari, Via Milano 43, 24047 Treviglio, Italy
| | - Claudio Beni
- Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria (CREA), Centro di Ricerca Ingegneria e Trasformazioni Agroalimentari, Via della Pascolare 15, 00015 Monterotondo, Italy
| | - Francesco Latterini
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035 Kórnik, Poland
| | - Roberto Lo Scalzo
- Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria (CREA), Centro di Ricerca Ingegneria e Trasformazioni Agroalimentari, Via Giacomo Venezian 26, 20133 Milano, Italy
| | - Antonio Scarfone
- Consiglio per la Ricerca in Agricoltura e l’Analisi dell’Economia Agraria (CREA), Centro di Ricerca Ingegneria e Trasformazioni Agroalimentari, Via della Pascolare 15, 00015 Monterotondo, Italy
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9
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Geest EA, Baum KA. The Impact of Fire on Nectar Quality and Quantity for Insect Pollinator Communities. AMERICAN MIDLAND NATURALIST 2022. [DOI: 10.1674/0003-0031-187.2.268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Emily A. Geest
- Department of Integrative Biology, Oklahoma State University, 501 Life Sciences West, Stillwater 74078
| | - Kristen A. Baum
- Department of Integrative Biology, Oklahoma State University, 501 Life Sciences West, Stillwater 74078
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10
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Finkelstein CJ, CaraDonna PJ, Gruver A, Welti EA, Kaspari M, Sanders NJ. Sodium-enriched floral nectar increases pollinator visitation rate and diversity. Biol Lett 2022; 18:20220016. [PMID: 35232272 PMCID: PMC8889166 DOI: 10.1098/rsbl.2022.0016] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Plants have evolved a variety of approaches to attract pollinators, including enriching their nectar with essential nutrients. Because sodium is an essential nutrient for pollinators, and sodium concentration in nectar can vary both within and among species, we explored whether experimentally enriching floral nectar with sodium in five plant species would influence pollinator visitation and diversity. We found that the number of visits by pollinators increased on plants with sodium-enriched nectar, regardless of plant species, relative to plants receiving control nectar. Similarly, the number of species visiting plants with sodium-enriched nectar was twice that of controls. Our findings suggest that sodium in floral nectar may play an important but unappreciated role in the ecology and evolution of plant-pollinator mutualisms.
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Affiliation(s)
- Carrie J. Finkelstein
- Environmental Program, Rubenstein School of Environment and Natural Resources, University of Vermont, Burlington, VT 05405, USA
| | - Paul J. CaraDonna
- Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60647, USA,Plant Biology and Conservation, Northwestern University, Evanston, IL 60208, USA,Rocky Mountain Biological Laboratory, P.O. Box 519, Crested Butte, CO 81224, USA
| | - Andrea Gruver
- Chicago Botanic Garden, 1000 Lake Cook Road, Glencoe, IL 60647, USA,Plant Biology and Conservation, Northwestern University, Evanston, IL 60208, USA
| | - Ellen A. R. Welti
- Conservation Ecology Center, Smithsonian Conservation Biology Institute, Front Royal, VA, USA
| | - Michael Kaspari
- Department of Biology, Geographical Ecology Group, University of Oklahoma, Norman, OK 73019, USA
| | - Nathan J. Sanders
- Rocky Mountain Biological Laboratory, P.O. Box 519, Crested Butte, CO 81224, USA,Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA
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11
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Brzosko E, Bajguz A, Burzyńska J, Chmur M. Nectar Chemistry or Flower Morphology-What Is More Important for the Reproductive Success of Generalist Orchid Epipactis palustris in Natural and Anthropogenic Populations? Int J Mol Sci 2021; 22:12164. [PMID: 34830045 PMCID: PMC8618778 DOI: 10.3390/ijms222212164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/06/2021] [Accepted: 11/08/2021] [Indexed: 11/17/2022] Open
Abstract
The aim of this study was to determine the level of reproductive success (RS) in natural and anthropogenic populations of generalist orchid Epipactis palustris and its dependence on flower structure and nectar composition, i.e., amino acids and sugars. We found that both pollinaria removal and female reproductive success were high and similar in all populations, despite differences in flower traits and nectar chemistry. Flower structures were weakly correlated with parameters of RS. Nectar traits were more important in shaping RS; although, we noted differentiated selection on nectar components in distinct populations. Individuals in natural populations produced nectar with a larger amount of sugars and amino acids. The sucrose to (fructose and glucose) ratio in natural populations was close to 1, while in anthropogenic ones, a clear domination of fructose and glucose was noted. Our results indicate that the flower traits and nectar composition of E. palustris reflect its generalist character and meet the requirements of a wide range of pollinators, differing according to body sizes, mouth apparatus, and dietary needs. Simultaneously, differentiation of nectar chemistry suggests a variation of pollinator assemblages in particular populations or domination of their some groups. To our knowledge, a comparison of nectar chemistry between natural and anthropogenic populations of orchids is reported for the first time in this paper.
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Affiliation(s)
- Emilia Brzosko
- Faculty of Biology, University of Bialystok, Ciolkowskiego 1J, 15-245 Bialystok, Poland; (J.B.); (M.C.)
| | - Andrzej Bajguz
- Faculty of Biology, University of Bialystok, Ciolkowskiego 1J, 15-245 Bialystok, Poland; (J.B.); (M.C.)
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12
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Jachuła J, Denisow B, Wrzesień M. Habitat heterogeneity helps to mitigate pollinator nectar sugar deficit and discontinuity in an agricultural landscape. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 782:146909. [PMID: 33848857 DOI: 10.1016/j.scitotenv.2021.146909] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 03/28/2021] [Accepted: 03/29/2021] [Indexed: 06/12/2023]
Abstract
The scarcity of floral resources and their seasonal discontinuity are considered as major factors for pollinator decline in intensified agricultural landscapes worldwide. The consequences are detrimental for the stability of the environment and ecosystems. Here, we quantified the production of nectar sugars in plant species occurring in man-made, non-cropped areas (non-forest woody vegetation, road verges, railway embankments, field margins, fallow areas) of an agricultural landscape in SE Poland. We also assessed changes in the availability of sugar resources both in space (habitat and landscape scales) and in time (throughout the flowering season), and checked to what extent the sugar demands of honeybees and bumblebees are met at the landscape scale. At landscape-level, 37.6% of the available sugar resources are produced in man-made, non-cropped habitats, while 32.6% and 15.0% of sugars derive from winter rape crops and forest vegetation, respectively. Nectar sugar supplies vary greatly between man-made, non-cropped habitat types/sub-types. These areas are characterized by a high richness of nectar-producing species. However, a predominant role in total sugar resources is ascribable to a few species. Strong fluctuations in nectar resources are recorded throughout the flowering season. March and June are periods with food shortages. Abundant nectar sugars are generally found in April-May, mainly due to the mass flowering of nectar-yielding species in the forests, meadows/pastures and orchards/rapeseed crops. Heterogeneity of man-made, non-cropped habitats is essential to support the supply of July-October nectar sugars for honeybees and bumblebees. Reduced flowering in man-made non-cropped habitats can generate serious food deficiencies, as from summer towards the end of the flowering season >90% of sugars are provided by the flora of these areas. Therefore, highly nectar-yielding plant species that flower during periods of expected food shortages should be a priority for conservation and restoration programs.
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Affiliation(s)
- Jacek Jachuła
- Department of Botany and Plant Physiology, Subdepartment of Plant Biology, University of Life Sciences, 15 Akademicka St., 20-950 Lublin, Poland
| | - Bożena Denisow
- Department of Botany and Plant Physiology, Subdepartment of Plant Biology, University of Life Sciences, 15 Akademicka St., 20-950 Lublin, Poland.
| | - Małgorzata Wrzesień
- Department of Botany, Mycology, and Ecology, Maria Curie-Sklodowska University, 19 Akademicka St., 20-033 Lublin, Poland.
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Grant EL, Wallace HM, Brooks PR, Burwell C, Reddell PW, Ogbourne SM. Floral attraction and flower visitors of a subcanopy, tropical rainforest tree, Fontainea picrosperma. Ecol Evol 2021; 11:10468-10482. [PMID: 34367589 PMCID: PMC8328466 DOI: 10.1002/ece3.7850] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 06/02/2021] [Accepted: 06/11/2021] [Indexed: 11/08/2022] Open
Abstract
Flowering plants in tropical rainforests rely heavily on pollen vectors for successful reproduction. Research into pollination systems in tropical rainforests is dominated by canopy species, while subcanopy plant-pollinator interactions remain under-represented. The microclimate beneath the rainforest canopy is characterized by low light levels and is markedly different from the canopy environment that receives more light energy.We studied the floral attractants and floral visitors of a dioecious, subcanopy tree, Fontainea picrosperma (Euphorbiaceae), in the Wet Tropics bioregion of northern Queensland, Australia.We found that wind pollination is rare and male and female flowers do not produce nectar. Female flowers are likely pollinated due to their perceptual similarity to pollen-offering male flowers. Female flowers had the same scent profile as male flowers, and floral scent was an important floral attractant that acted to regulate pollinator behavior. The two most abundant scent compounds present in the floral bouquet were benzyl alcohol and 4-oxoisophorone. These compounds are ubiquitous in nature and are known to attract a wide variety of insects. Both day-time and night-time pollinators contributed to successful pollen deposition on the stigma, and diurnal flower visitors were identified from several orders of insects including beetles, flies, predatory wasps, and thrips. Fontainea picrosperma is therefore likely to be pollinated by a diverse array of small insects.Synthesis. Our data indicate that F. picrosperma has a generalist, entomophilous pollination syndrome. The rainforest subcanopy is a distinctive environment characterized by low light levels, low or turbulent wind speeds, and relatively high humidity. Female flowers of F. picrosperma exhibit cost-saving strategies by not producing nectar and mimicking the smell of reward-offering male flowers. Insects opportunistically forage on or inhabit flowers, and pollination occurs from a pool of small insects with low energy requirements that are found beneath the rainforest canopy.
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Affiliation(s)
- Elektra L. Grant
- Genecology Research CentreUniversity of the Sunshine CoastSippy DownsQldAustralia
| | - Helen M. Wallace
- Centre for Planetary Health and Food Security and Griffith School of Environment and ScienceGriffith UniversityNathanQldAustralia
| | - Peter R. Brooks
- Genecology Research CentreUniversity of the Sunshine CoastSippy DownsQldAustralia
| | - Chris Burwell
- Biodiversity and Geosciences ProgramQueensland MuseumSouth BrisbaneQldAustralia
- Griffith School of Environment and ScienceGriffith UniversityNathanQldAustralia
| | | | - Steven M. Ogbourne
- Genecology Research CentreUniversity of the Sunshine CoastSippy DownsQldAustralia
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Scaccabarozzi D, Dods K, Le TT, Gummer JPA, Lussu M, Milne L, Campbell T, Wafujian BP, Priddis C. Factors driving the compositional diversity of Apis mellifera bee venom from a Corymbia calophylla (marri) ecosystem, Southwestern Australia. PLoS One 2021; 16:e0253838. [PMID: 34191849 PMCID: PMC8244862 DOI: 10.1371/journal.pone.0253838] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 06/15/2021] [Indexed: 11/23/2022] Open
Abstract
Bee venom (BV) is the most valuable product harvested from honeybees ($30 - $300 USD per gram) but marginally produced in apiculture. Though widely studied and used in alternative medicine, recent efforts in BV research have focused on its therapeutic and cosmetic applications, for the treatment of degenerative and infectious diseases. The protein and peptide composition of BV is integral to its bioactivity, yet little research has investigated the ecological factors influencing the qualitative and quantitative variations in the BV composition. Bee venom from Apis mellifera ligustica (Apidae), collected over one flowering season of Corymbia calophylla (Myrtaceae; marri) was characterized to test if the protein composition and amount of BV variation between sites is influenced by i) ecological factors (temperature, relative humidity, flowering index and stage, nectar production); ii) management (nutritional supply and movement of hives); and/or iii) behavioural factors. BV samples from 25 hives across a 200 km-latitudinal range in Southwestern Australia were collected using stimulatory devices. We studied the protein composition of BV by mass spectrometry, using a bottom-up proteomics approach. Peptide identification utilised sequence homology to the A. mellifera reference genome, assembling a BV peptide profile representative of 99 proteins, including a number of previously uncharacterised BV proteins. Among ecological factors, BV weight and protein diversity varied by temperature and marri flowering stage but not by index, this latter suggesting that inter and intra-year flowering index should be further explored to better appreciate this influence. Site influenced BV protein diversity and weight difference in two sites. Bee behavioural response to the stimulator device impacted both the protein profile and weight, whereas management factors did not. Continued research using a combination of proteomics, and bio-ecological approaches is recommended to further understand causes of BV variation in order to standardise and improve the harvest practice and product quality attributes.
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Affiliation(s)
- Daniela Scaccabarozzi
- Research Service, ChemCentre, Resources and Chemistry Precinct, Bentley, WA, Australia
| | - Kenneth Dods
- Research and Innovation Division, ChemCentre, Resources and Chemistry Precinct, Bentley, WA, Australia
| | - Thao T. Le
- School of Science, Edith Cowan University, Joondalup, WA, Australia
| | - Joel P. A. Gummer
- Research and Innovation Division, ChemCentre, Resources and Chemistry Precinct, Bentley, WA, Australia
- School of Science, Edith Cowan University, Joondalup, WA, Australia
| | - Michele Lussu
- Regional Institute for Floriculture (IRF), San Remo, Italy
| | - Lynne Milne
- Research Service, ChemCentre, Resources and Chemistry Precinct, Bentley, WA, Australia
| | - Tristan Campbell
- Research Service, ChemCentre, Resources and Chemistry Precinct, Bentley, WA, Australia
| | | | - Colin Priddis
- Research and Innovation Division, ChemCentre, Resources and Chemistry Precinct, Bentley, WA, Australia
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Nectar Uptake of a Long-Proboscid Prosoeca Fly (Nemestrinidae)-Proboscis Morphology and Flower Shape. INSECTS 2021; 12:insects12040371. [PMID: 33924274 PMCID: PMC8074905 DOI: 10.3390/insects12040371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/15/2021] [Accepted: 04/17/2021] [Indexed: 11/17/2022]
Abstract
Several Prosoeca (Nemestinidae) species use a greatly elongated proboscis to drink nectar from long-tubed flowers. We studied morphological adaptations for nectar uptake of Prosoecamarinusi that were endemic to the Northern Cape of South Africa. Our study site was a small isolated area of semi-natural habitat, where the long-tubed flowers of Babiana vanzijliae (Iridaceae) were the only nectar source of P. marinusi, and these flies were the only insects with matching proboscis. On average, the proboscis measured 32.63 ± 2.93 mm in length and less than 0.5 mm in diameter. The short labella at the tip are equipped with pseudotracheae that open at the apical margin, indicating that nectar is extracted out of the floral tube with closed labella. To quantify the available nectar resources, measurements of the nectar volume were taken before the flies were active and after observed flower visits. On average, an individual fly took up approximately 1 µL of nectar per flower visit. The measured nectar quantities and the flower geometry allowed estimations of the nectar heights and predictions of necessary proboscis lengths to access nectar in a range of flower tube lengths.
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How Are the Flower Structure and Nectar Composition of the Generalistic Orchid Neottia ovata Adapted to a Wide Range of Pollinators? Int J Mol Sci 2021; 22:ijms22042214. [PMID: 33672302 PMCID: PMC7926835 DOI: 10.3390/ijms22042214] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 02/05/2021] [Accepted: 02/19/2021] [Indexed: 11/16/2022] Open
Abstract
Plant-pollinator interactions significantly influence reproductive success (RS) and drive the evolution of pollination syndromes. In the context of RS, mainly the role of flower morphology is touched. The importance of nectar properties is less studied, despite its significance in pollination effectiveness. Therefore, the aim of this study was to test selection on flower morphology and nectar chemistry in the generalistic orchid Neottia ovata. In 2019–2020, we measured three floral displays and six flower traits, pollinaria removal (PR), female reproductive success (FRS), and determined the soil properties. The sugars and amino acids (AAs) were analyzed using the HPLC method. Data were analyzed using multiple statistical methods (boxplots, ternary plot, one-way ANOVA, Kruskal-Wallis test, and PCA). Variation of flower structure and nectar chemistry and their weak correlation with RS confirms the generalistic character of N. ovata. In particular populations, different traits were under selection. PR was high and similar in all populations in both years, while FRS was lower and varied among populations. Nectar was dominated by glucose, fructose, and included 28 AAs (Ala and Glu have the highest content). Sugars and AAs influenced mainly FRS. Among soil parameters, carbon and carbon:nitrogen ratio seems to be the most important in shaping flower structure and nectar chemistry.
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Scaccabarozzi D, Campbell T, Dods K. A simple and effective ground‐based tool for sampling tree flowers at height for subsequent nectar extraction. Methods Ecol Evol 2020. [DOI: 10.1111/2041-210x.13453] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniela Scaccabarozzi
- School of Molecular and Life Sciences Curtin University Bentley WA Australia
- Department of Biology University of Naples Federico II Naples Italy
- Kings Park Science Department of Biodiversity, Conservation and Attractions West Perth WA Australia
| | - Tristan Campbell
- School of Electrical Engineering, Computing and Mathematical Sciences Curtin University Bentley WA Australia
| | - Kenneth Dods
- ChemCentre, Resources and Chemistry Precinct Bentley WA Australia
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18
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Bartoš M, Janeček Š, Janečková P, Chmelová E, Tropek R, Götzenberger L, Klomberg Y, Jersáková J. Are Reproductive Traits Related to Pollen Limitation in Plants? A Case Study from a Central European Meadow. PLANTS 2020; 9:plants9050640. [PMID: 32438589 PMCID: PMC7285000 DOI: 10.3390/plants9050640] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/07/2020] [Accepted: 05/16/2020] [Indexed: 11/16/2022]
Abstract
The deficiency of pollen grains for ovule fertilization can be the main factor limiting plant reproduction and fitness. Because of the ongoing global changes, such as biodiversity loss and landscape fragmentation, a better knowledge of the prevalence and predictability of pollen limitation is challenging within current ecological research. In our study we used pollen supplementation to evaluate pollen limitation (at the level of seed number and weight) in 22 plant species growing in a wet semi-natural meadow. We investigated the correlation between the pollen limitation index (PL) and floral traits associated with plant reproduction or pollinator foraging behavior. We recorded significant pollen limitation for approximately 41% of species (9 out of 22 surveyed). Seven species had a significant positive response in seed production and two species increased in seed weight after pollen supplementation. Considering traits, PL significantly decreased with the number of pollinator functional groups. The relationship of PL with other examined traits was not supported by our results. The causes of pollen limitation may vary among species with regard to (1) different reproductive strategies and life history, and/or (2) temporary changes in influence of biotic and abiotic factors at a site.
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Affiliation(s)
- Michael Bartoš
- Institute of Botany, The Czech Academy of Sciences, 37981 Třeboň, Czech Republic;
- Correspondence: ; Tel.:+420-380-720-330
| | - Štěpán Janeček
- Department of Ecology, Faculty of Science, Charles University, 12843 Praha, Czech Republic; (Š.J.); (P.J.); (E.C.); (R.T.); (Y.K.)
| | - Petra Janečková
- Department of Ecology, Faculty of Science, Charles University, 12843 Praha, Czech Republic; (Š.J.); (P.J.); (E.C.); (R.T.); (Y.K.)
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic;
| | - Eliška Chmelová
- Department of Ecology, Faculty of Science, Charles University, 12843 Praha, Czech Republic; (Š.J.); (P.J.); (E.C.); (R.T.); (Y.K.)
- Biology Centre, Institute of Entomology, The Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
| | - Robert Tropek
- Department of Ecology, Faculty of Science, Charles University, 12843 Praha, Czech Republic; (Š.J.); (P.J.); (E.C.); (R.T.); (Y.K.)
- Biology Centre, Institute of Entomology, The Czech Academy of Sciences, 37005 České Budějovice, Czech Republic
| | - Lars Götzenberger
- Institute of Botany, The Czech Academy of Sciences, 37981 Třeboň, Czech Republic;
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic;
| | - Yannick Klomberg
- Department of Ecology, Faculty of Science, Charles University, 12843 Praha, Czech Republic; (Š.J.); (P.J.); (E.C.); (R.T.); (Y.K.)
| | - Jana Jersáková
- Faculty of Science, University of South Bohemia, 37005 České Budějovice, Czech Republic;
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19
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Dufour C, Fournier V, Giovenazzo P. The impact of lowbush blueberry (Vaccinium angustifolium Ait.) and cranberry (Vaccinium macrocarpon Ait.) pollination on honey bee (Apis mellifera L.) colony health status. PLoS One 2020; 15:e0227970. [PMID: 31978125 PMCID: PMC6980599 DOI: 10.1371/journal.pone.0227970] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 01/04/2020] [Indexed: 11/18/2022] Open
Abstract
Commercial lowbush blueberry (Vaccinium angustifolium Ait.) and cranberry (Vaccinium macrocarpon Ait.) crops benefit from the presence of honey bee (Apis mellifera L.) for pollination. Unfortunately, beekeepers are observing negative impacts of pollination services on honey bee colonies. In this study, we investigated three beekeeping management strategies (MS) and measured their impact on honey bee colony health and development. Experimental groups (five colonies/MS) were: A) Control farmland honey producing MS (control MS); B) Blueberry pollination MS (blueberry MS); C) Cranberry pollination MS (cranberry MS) and D) Double pollination MS, blueberry followed by cranberry (double MS). Our goals were to 1) compare floral abundance and attractiveness of foraging areas to honey bees between apiaries using a Geographic Information System, and 2) compare honey bee colony health status and population development between MS during a complete beekeeping season. Our results show significantly lower floral abundance and honey bee attractiveness of foraging areas during cranberry pollination compared to the other environments. The blueberry pollination site seemed to significantly reduce brood population in the colonies who provided those services (blueberry MS and double MS). The cranberry pollination site seemed to significantly reduce colony weight gain (cranberry MS and double MS) and induce a significantly higher winter mortality rate (cranberry MS). We also measured significantly higher levels of Black queen cell virus and Sacbrood virus in the MS providing cranberry pollination (cranberry MS and double MS).
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Affiliation(s)
- Claude Dufour
- Département de biologie, Université Laval, Québec, Québec, Canada
| | - Valérie Fournier
- Centre de recherche et innovation sur les végétaux, Université Laval, Québec, Québec, Canada
| | - Pierre Giovenazzo
- Département de biologie, Université Laval, Québec, Québec, Canada
- * E-mail:
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Bartoš M, Janeček Š, Janečková P, Padyšáková E, Tropek R, Götzenberger L, Klomberg Y, Jersáková J. Self-compatibility and autonomous selfing of plants in meadow communities. PLANT BIOLOGY (STUTTGART, GERMANY) 2020; 22:120-128. [PMID: 31549455 DOI: 10.1111/plb.13049] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 08/30/2019] [Indexed: 06/10/2023]
Abstract
One of the most fundamental, although controversial, questions related to the evolution of plant mating systems is the distribution of outcrossing rates. Self-compatibility, and especially autonomous self-pollination, can become particularly beneficial in anthropogenically degraded habitats with impoverished pollinator assemblages and increased pollen limitation. In a hand-pollination experiment with 46 meadow plants from the Železné hory Mts., Czech Republic, we evaluated the species' ability to adopt different mating systems. For a subset of the species, we also tested seed germination for inbreeding depression. Subsequently, we analysed relationships between the species' mating systems and 12 floral and life-history traits. We found a relatively discrete distribution of the studied species into four groups. Fully and partially self-incompatible species formed the largest group, followed by self-compatible non-selfers and mixed mating species. The germination experiment showed an absence of inbreeding depression in 19 out of 22 examined species. Nectar sugar per flower, nectar sugar per shoot and dichogamy were significant associated with the mating system. Spontaneous selfing ability and self-incompatibility in species of the meadow communities had a discrete distribution, conforming to the general distribution of mating and breeding systems in angiosperms. The low frequency of spontaneous selfers and the lack of inbreeding depression at germination suggest the existence of a selection against selfing at the later ontogenetic stages. Some floral traits, such as the level of dichogamy and amount of nectar reward, may strongly impact the balance between selfing and outcrossing rates in the self-compatible species and thus shape the evolution of mating systems.
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Affiliation(s)
- M Bartoš
- Institute of Botany, The Czech Academy of Sciences, Třeboň, Czech Republic
| | - Š Janeček
- Department of Ecology, Faculty of Science, Charles University, Praha, Czech Republic
| | - P Janečková
- Department of Ecology, Faculty of Science, Charles University, Praha, Czech Republic
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - E Padyšáková
- Department of Ecology, Faculty of Science, Charles University, Praha, Czech Republic
- Biology Centre, Institute of Entomology, The Czech Academy of Sciences, České Budějovice, Czech Republic
| | - R Tropek
- Department of Ecology, Faculty of Science, Charles University, Praha, Czech Republic
- Biology Centre, Institute of Entomology, The Czech Academy of Sciences, České Budějovice, Czech Republic
| | - L Götzenberger
- Institute of Botany, The Czech Academy of Sciences, Třeboň, Czech Republic
| | - Y Klomberg
- Department of Ecology, Faculty of Science, Charles University, Praha, Czech Republic
| | - J Jersáková
- Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
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21
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Płachno BJ, Stpiczyńska M, Świątek P, Lambers H, Cawthray GR, Nge FJ, Silva SR, Miranda VFO. Floral micromorphology and nectar composition of the early evolutionary lineage Utricularia (subgenus Polypompholyx, Lentibulariaceae). PROTOPLASMA 2019; 256:1531-1543. [PMID: 31190095 PMCID: PMC6820596 DOI: 10.1007/s00709-019-01401-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 06/04/2019] [Indexed: 05/20/2023]
Abstract
Utricularia (Lentibulariaceae) is a genus comprising around 240 species of herbaceous, carnivorous plants. Utricularia is usually viewed as an insect-pollinated genus, with the exception of a few bird-pollinated species. The bladderworts Utricularia multifida and U. tenella are interesting species because they represent an early evolutionary Utricularia branch and have some unusual morphological characters in their traps and calyx. Thus, our aims were to (i) determine whether the nectar sugar concentrations and composition in U. multifida and U. tenella are similar to those of other Utricularia species from the subgenera Polypompholyx and Utricularia, (ii) compare the nectary structure of U. multifida and U. tenella with those of other Utricularia species, and (iii) determine whether U. multifida and U. tenella use some of their floral trichomes as an alternative food reward for pollinators. We used light microscopy, histochemistry, and scanning and transmission electron microscopy to address those aims. The concentration and composition of nectar sugars were analysed using high-performance liquid chromatography. In all of the examined species, the floral nectary consisted of a spur bearing glandular trichomes. The spur produced and stored the nectar. We detected hexose-dominated (fructose + glucose) nectar in U. multifida and U. tenella as well as in U. violacea. In both U. multifida and U. tenella, there were trichomes that blocked the entrance into the throat and spur. Because these trichomes were rich in chromoplasts and contained lipid droplets, they may form an additional visual attractant. Bearing in mind the phylogenetic hypothesis for the genus, we suggest that an early ancestor of Utricularia had a nectariferous spur flower with a lower lip that formed a wide landing platform for bee pollinators.
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Affiliation(s)
- Bartosz J Płachno
- Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University in Kraków, 9 Gronostajowa St., 30-387, Cracow, Poland.
| | - Małgorzata Stpiczyńska
- Botanic Garden, Faculty of Biology, University of Warsaw, Al. Ujazdowskie 4, 00-478, Warsaw, Poland
| | - Piotr Świątek
- Department of Animal Histology and Embryology, University of Silesia in Katowice, 9 Bankowa St., 40-007, Katowice, Poland
| | - Hans Lambers
- School of Biological Sciences, University of Western Australia, (M084) 35 Stirling Highway, Crawley Perth, WA, 6009, Australia
| | - Gregory R Cawthray
- School of Biological Sciences, University of Western Australia, (M084) 35 Stirling Highway, Crawley Perth, WA, 6009, Australia
| | - Francis J Nge
- School of Biological Sciences, Faculty of Science, The University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Saura R Silva
- Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal, Departamento de Biologia Aplicada à Agropecuária, Universidade Estadual Paulista (Unesp), São Paulo, Brazil
| | - Vitor F O Miranda
- Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal, Departamento de Biologia Aplicada à Agropecuária, Universidade Estadual Paulista (Unesp), São Paulo, Brazil
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22
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Aronne G, Malara P. Fiber-optic refractometer for in vivo sugar concentration measurements of low-nectar-producing flowers. THE NEW PHYTOLOGIST 2019; 224:987-993. [PMID: 31364780 DOI: 10.1111/nph.16084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 07/22/2019] [Indexed: 06/10/2023]
Abstract
Sugar concentration in floral nectars is an assessment required in several diverse fields of application. The widely used analysis, consisting of nectar extraction with a microcapillary and sugar concentration measurement with a light refractometer, is not reliable when the nectar is secreted in small quantities, unextractable with a microcapillary. Ancillary methods adopted in such cases are destructive, rather complicated and often provide much less precise and accurate results. The microscopic-size, low cost and biocompatibility of optical fibers were exploited to deliver light directly inside the flower with minimal invasiveness and measure instantaneously the refractometric properties of the nectar without extracting it. After comparing the new and old methods using two known nectariferous species, the new approach was validated on Primula palinuri, whose nectar is unextractable with microcapillaries. The fiber-optic probe was able to measure the nectar refractive index in P. palinuri flowers making it possible to highlight a previously undetected significant trend of the sugar concentration throughout the long anthesis of the single flowers. Changes in nectar concentrations are similar in both longistylous and brevistylous flowers. The fiber-optic refractometer is an advancement of light refractometer analysis. Further customization of the laboratory set-up into portable equipment will boost applications.
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Affiliation(s)
- Giovanna Aronne
- Department of Agricultural Sciences, University of Naples Federico II, via Università 100, 80055, Portici (NA), Italy
| | - Pietro Malara
- CNR-Istituto Nazionale di Ottica, via Campi Flegrei 34 (comprensorio A. Olivetti), 80078, Pozzuoli (NA), Italy
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23
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Parachnowitsch AL, Manson JS, Sletvold N. Evolutionary ecology of nectar. ANNALS OF BOTANY 2019; 123:247-261. [PMID: 30032269 PMCID: PMC6344224 DOI: 10.1093/aob/mcy132] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Accepted: 06/16/2018] [Indexed: 05/24/2023]
Abstract
Background Floral nectar is an important determinant of plant-pollinator interactions and an integral component of pollination syndromes, suggesting it is under pollinator-mediated selection. However, compared to floral display traits, we know little about the evolutionary ecology of nectar. Combining a literature review with a meta-analysis approach, we summarize the evidence for heritable variation in nectar traits and link this variation to pollinator response and plant fitness. We further review associations between nectar traits and floral signals and discuss them in the context of honest signalling and targets of selection. Scope Although nectar is strongly influenced by environmental factors, heritable variation in nectar production rate has been documented in several populations (mean h2 = 0.31). Almost nothing is known about heritability of other nectar traits, such as sugar and amino acid concentrations. Only a handful of studies have quantified selection on nectar traits, and few find statistically significant selection. Pollinator responses to nectar traits indicate they may drive selection, but studies tying pollinator preferences to plant fitness are lacking. So far, only one study conclusively identified pollinators as selective agents on a nectar trait, and the role of microbes, herbivores, nectar robbers and abiotic factors in nectar evolution is largely hypothetical. Finally, there is a trend for positive correlations among floral cues and nectar traits, indicating honest signalling of rewards. Conclusions Important progress can be made by studies that quantify current selection on nectar in natural populations, as well as experimental approaches that identify the target traits and selective agents involved. Signal-reward associations suggest that correlational selection may shape evolution of nectar traits, and studies exploring these more complex forms of natural selection are needed. Many questions about nectar evolution remain unanswered, making this a field ripe for future research.
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Affiliation(s)
- Amy L Parachnowitsch
- Plant Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
- Department of Biology, University of New Brunswick, Fredericton, New Brunswick, Canada
| | - Jessamyn S Manson
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Nina Sletvold
- Plant Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
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Power EF, Stabler D, Borland AM, Barnes J, Wright GA. Analysis of nectar from low-volume flowers: A comparison of collection methods for free amino acids. Methods Ecol Evol 2017; 9:734-743. [PMID: 29938013 PMCID: PMC5993345 DOI: 10.1111/2041-210x.12928] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Accepted: 10/20/2017] [Indexed: 11/29/2022]
Abstract
Floral nectar is a reward offered by flowering plants to visiting pollinators. Nectar chemistry is important for understanding plant nutrient allocation and plant–pollinator interactions. However, many plant species are difficult to sample as their flowers are small and produce low amounts of nectar. We compared the effects of different methods of nectar collection on the amino acid composition of flowers with low volumes of nectar. We used five methods to collect nectar from 60 (5 × 12) Calluna vulgaris flowers: microcapillary tubes, a low‐volume flower rinse (the micro‐rinse method, using 2 μl water), filter paper, a high‐volume flower rinse (2 ml water) and a flower wash (2 ml water). We analysed the samples for free amino acids using quantitative UHPLC methods . We found that the micro‐rinse method (rinsing the nectary with enough water to only cover the nectary) recovered amino acid proportions similar to raw nectar extracted using microcapillary tubes. The filter paper, 2 ml rinse and 2 ml wash methods measured significantly higher values of free amino acids and also altered the profile of amino acids. We discuss our concerns about the increased contamination risk of the filter paper and high‐volume rinse and wash samples from dried nectar across the floral tissue (nectar unavailable to floral visitors), pollen, vascular fluid and cellular fluid. Our study will enable researchers to make informed decisions about nectar collection methods depending on their intended chemical analysis. These methods of sampling will enable researchers to examine a larger array of plant species' flowers to include those with low volumes of nectar.
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Affiliation(s)
- Eileen F Power
- Institute of Neuroscience Newcastle University Newcastle upon Tyne UK.,Botany Department School of Natural Sciences Trinity College Dublin Dublin 2 Ireland
| | - Daniel Stabler
- Institute of Neuroscience Newcastle University Newcastle upon Tyne UK.,School of Natural and Environmental Science: Biology Newcastle University Newcastle upon Tyne UK
| | - Anne M Borland
- School of Natural and Environmental Science: Biology Newcastle University Newcastle upon Tyne UK
| | - Jeremy Barnes
- School of Natural and Environmental Science: Biology Newcastle University Newcastle upon Tyne UK
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25
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Amato B, Petit S. A review of the methods for storing floral nectars in the field. PLANT BIOLOGY (STUTTGART, GERMANY) 2017; 19:497-503. [PMID: 28303638 DOI: 10.1111/plb.12565] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 03/11/2017] [Indexed: 06/06/2023]
Abstract
The knowledge of floral nectar sugar characteristics, such as concentration, ratio and mass, is essential to understand the complex nature of nectar production and pollination systems. Although nectar is commonly stored in ecology, storage reliability and effectiveness have rarely been quantified. Inappropriate nectar storage between sampling and analysis can alter nectar chemistry as a result of enzyme or microbial action. Our review of the literature indicates that measures to preserve nectar sugars before analysis include refrigeration, freezing, the addition of an antimicrobial agent, spotting and drying on filter paper, the addition of a desiccant or a combination of these storage treatments. Nectar stored on filter paper is removed by washing with a solvent before analysis. Elution methods are often complex, not standardised and poorly reported in published work. Existing storage methods have generally been used without an evaluation of their impact on results, but evidence suggests a potentially large impact on result accuracy. Future studies should report storage treatments and elution methods to legitimise comparison among independent studies and provide unbiased evaluation of the results. In view of the wide range of storage methods used and lack of verification of their appropriateness, is imperative that standardised and effective methods be developed to ensure that results are reliable. We recommend the prompt analysis of nectar, detailed description of methods, including size of filter paper and method of elution, and use of sterile techniques.
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Affiliation(s)
- B Amato
- Natural and Built Environments, University of South Australia, Mawson Lakes, SA, Australia
| | - S Petit
- Natural and Built Environments, University of South Australia, Mawson Lakes, SA, Australia
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26
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Cabana F, Dierenfeld E, Wirdateti W, Donati G, Nekaris K. The seasonal feeding ecology of the javan slow loris (nycticebus javanicus). AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2017; 162:768-781. [DOI: 10.1002/ajpa.23168] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Revised: 12/16/2016] [Accepted: 12/21/2016] [Indexed: 12/21/2022]
Affiliation(s)
- Francis Cabana
- Nocturnal Primate Research Group, Oxford Brookes University; Oxford OX3 0BP UK
- Wildlife Reserves Singapore; Singapore 729826 Singapore
| | | | | | - Giuseppe Donati
- Nocturnal Primate Research Group, Oxford Brookes University; Oxford OX3 0BP UK
| | - K.A.I. Nekaris
- Nocturnal Primate Research Group, Oxford Brookes University; Oxford OX3 0BP UK
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27
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Abrahamczyk S, Kessler M, Hanley D, Karger DN, Müller MPJ, Knauer AC, Keller F, Schwerdtfeger M, Humphreys AM. Pollinator adaptation and the evolution of floral nectar sugar composition. J Evol Biol 2016; 30:112-127. [PMID: 27747987 DOI: 10.1111/jeb.12991] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 10/08/2016] [Accepted: 10/12/2016] [Indexed: 12/30/2022]
Abstract
A long-standing debate concerns whether nectar sugar composition evolves as an adaptation to pollinator dietary requirements or whether it is 'phylogenetically constrained'. Here, we use a modelling approach to evaluate the hypothesis that nectar sucrose proportion (NSP) is an adaptation to pollinators. We analyse ~ 2100 species of asterids, spanning several plant families and pollinator groups (PGs), and show that the hypothesis of adaptation cannot be rejected: NSP evolves towards two optimal values, high NSP for specialist-pollinated and low NSP for generalist-pollinated plants. However, the inferred adaptive process is weak, suggesting that adaptation to PG only provides a partial explanation for how nectar evolves. Additional factors are therefore needed to fully explain nectar evolution, and we suggest that future studies might incorporate floral shape and size and the abiotic environment into the analytical framework. Further, we show that NSP and PG evolution are correlated - in a manner dictated by pollinator behaviour. This contrasts with the view that a plant necessarily has to adapt its nectar composition to ensure pollination but rather suggests that pollinators adapt their foraging behaviour or dietary requirements to the nectar sugar composition presented by the plants. Finally, we document unexpectedly sucrose-poor nectar in some specialized nectarivorous bird-pollinated plants from the Old World, which might represent an overlooked form of pollinator deception. Thus, our broad study provides several new insights into how nectar evolves and we conclude by discussing why maintaining the conceptual dichotomy between adaptation and constraint might be unhelpful for advancing this field.
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Affiliation(s)
- S Abrahamczyk
- Nees Institute for Plant Biodiversity, University of Bonn, Bonn, Germany
| | - M Kessler
- Institute of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
| | - D Hanley
- Department of Biology, Long Island University - Post, Brookville, NY, USA
| | - D N Karger
- Institute of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
| | - M P J Müller
- Institute of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
| | - A C Knauer
- Institute of Systematic and Evolutionary Botany, University of Zurich, Zurich, Switzerland
| | - F Keller
- Institute of Plant Science, University of Zurich, Zurich, Switzerland
| | - M Schwerdtfeger
- Albrecht-v.-Haller Institute of Plant Science, University of Goettingen, Goettingen, Germany
| | - A M Humphreys
- Department of Life Sciences, Imperial College London, Berkshire, UK.,Department of Ecology, Environment and Plant Sciences, University of Stockholm, Stockholm, Sweden
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28
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Lai D, Pičmanová M, Abou Hachem M, Motawia MS, Olsen CE, Møller BL, Rook F, Takos AM. Lotus japonicus flowers are defended by a cyanogenic β-glucosidase with highly restricted expression to essential reproductive organs. PLANT MOLECULAR BIOLOGY 2015; 89:21-34. [PMID: 26249044 DOI: 10.1007/s11103-015-0348-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 07/16/2015] [Indexed: 05/08/2023]
Abstract
Flowers and leaves of Lotus japonicus contain α-, β-, and γ-hydroxynitrile glucoside (HNG) defense compounds, which are bioactivated by β-glucosidase enzymes (BGDs). The α-HNGs are referred to as cyanogenic glucosides because their hydrolysis upon tissue disruption leads to release of toxic hydrogen cyanide gas, which can deter herbivore feeding. BGD2 and BGD4 are HNG metabolizing BGD enzymes expressed in leaves. Only BGD2 is able to hydrolyse the α-HNGs. Loss of function mutants of BGD2 are acyanogenic in leaves but fully retain cyanogenesis in flowers pointing to the existence of an alternative cyanogenic BGD in flowers. This enzyme, named BGD3, is identified and characterized in this study. Whereas all floral tissues contain α-HNGs, only those tissues in which BGD3 is expressed, the keel and the enclosed reproductive organs, are cyanogenic. Biochemical analysis, active site architecture molecular modelling, and the observation that L. japonicus accessions lacking cyanogenic flowers contain a non-functional BGD3 gene, all support the key role of BGD3 in floral cyanogenesis. The nectar of L. japonicus flowers was also found to contain HNGs and additionally their diglycosides. The observed specialisation in HNG based defence in L. japonicus flowers is discussed in the context of balancing the attraction of pollinators with the protection of reproductive structures against herbivores.
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Affiliation(s)
- Daniela Lai
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark.
| | - Martina Pičmanová
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark.
| | - Maher Abou Hachem
- Department of Systems Biology, Technical University of Denmark, 2800, Kongens Lyngby, Denmark.
| | - Mohammed Saddik Motawia
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark.
| | - Carl Erik Olsen
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark.
| | - Birger Lindberg Møller
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark.
- Carlsberg Laboratory, Gamle Carlsberg Vej 10, 1799, Copenhagen V, Denmark.
| | - Fred Rook
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark.
| | - Adam M Takos
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg C, Denmark.
- Evolva Copenhagen, Lersø Parkallé 42-44, 2100, Copenhagen Ø, Denmark.
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Soto VC, Maldonado IB, Jofré VP, Galmarini CR, Silva MF. Direct analysis of nectar and floral volatile organic compounds in hybrid onions by HS-SPME/GC–MS: Relationship with pollination and seed production. Microchem J 2015. [DOI: 10.1016/j.microc.2015.04.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Williams S, King J, Revell M, Manley-Harris M, Balks M, Janusch F, Kiefer M, Clearwater M, Brooks P, Dawson M. Regional, annual, and individual variations in the dihydroxyacetone content of the nectar of ma̅nuka (Leptospermum scoparium) in New Zealand. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2014; 62:10332-10340. [PMID: 25277074 DOI: 10.1021/jf5045958] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A method was designed and validated for the analysis of dihydroxyacetone in the floral nectar of ma̅nuka (Leptospermum scoparium). The method was applied to samples collected from different regions of the North Island and the Nelson region of the upper South Island of New Zealand during the period 2009-2012 as well as to nectar samples from some Australian Leptospermum species. The ratio of dihydroxyacetone to total sugar (DHA/Tsugar) was classified as low (<0.001 mg/mg), moderate (0.001-0.002 mg/mg), or high (>0.002 mg/mg). Inter- and intraregional variation were observed as well as interannual variation with variation from low to high classification occurring within one region and from low to moderate between years. Australian species also demonstrated elevated levels of dihydroxyacetone in the nectar. Some garden cultivars were shown to produce very high nectar DHA/Tsugar, and a survey of cultivars was undertaken; cultivars with single-flowered red or pink flowers were the most common producers of very high nectar DHA/Tsugar.
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Affiliation(s)
- Simon Williams
- Chemistry, School of Science, University of Waikato , Hamilton 3216, New Zealand
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31
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Quinn CF, Prins CN, Freeman JL, Gross AM, Hantzis LJ, Reynolds RJB, Yang SI, Covey PA, Bañuelos GS, Pickering IJ, Fakra SC, Marcus MA, Arathi HS, Pilon-Smits EAH. Selenium accumulation in flowers and its effects on pollination. THE NEW PHYTOLOGIST 2011; 192:727-37. [PMID: 21793829 DOI: 10.1111/j.1469-8137.2011.03832.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
• Selenium (Se) hyperaccumulation has a profound effect on plant-arthropod interactions. Here, we investigated floral Se distribution and speciation in flowers and the effects of floral Se on pollen quality and plant-pollinator interactions. • Floral Se distribution and speciation were compared in Stanleya pinnata, an Se hyperaccumulator, and Brassica juncea, a comparable nonhyperaccumulator. Pollen germination was measured from plants grown with varying concentrations of Se and floral visitation was compared between plants with high and low Se. • Stanleya pinnata preferentially allocated Se to flowers, as nontoxic methyl-selenocysteine (MeSeCys). Brassica juncea had higher Se concentrations in leaves than flowers, and a lower fraction of MeSeCys. For B. juncea, high floral Se concentration impaired pollen germination; in S. pinnata Se had no effect on pollen germination. Floral visitors collected from Se-rich S. pinnata contained up to 270 μg g(-1), concentrations toxic to many herbivores. Indeed, floral visitors showed no visitation preference between high- and low-Se plants. Honey from seleniferous areas contained 0.4-1 μg Se g(-1), concentrations that could provide human health benefits. • This study is the first to shed light on the possible evolutionary cost, through decreased pollen germination in B. juncea, of Se accumulation and has implications for the management of seleniferous areas.
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Affiliation(s)
- Colin F Quinn
- Department of Biology, Colorado State University, Fort Collins, CO 80532, USA
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32
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Morrant DS, Petit S, Schumann R. Floral nectar sugar composition and flowering phenology of the food plants used by the western pygmy possum, Cercartetus concinnus, at Innes National Park, South Australia. Ecol Res 2010. [DOI: 10.1007/s11284-009-0687-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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