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Yuan Y, Yan S, Wu L, Xu H, Mu G, Xue X. Exploring formation of turanose in honey via stable isotope labelling and high-resolution mass spectrometry analysis. Food Chem 2024; 460:140471. [PMID: 39059326 DOI: 10.1016/j.foodchem.2024.140471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 06/30/2024] [Accepted: 07/13/2024] [Indexed: 07/28/2024]
Abstract
Turanose, an isomer of sucrose, naturally exists in honey. Previous study indicated that turanose content increased gradually in acacia honey as honeybees brewed honey in the hive. However, it is unclear how turanose is generated in honey. We hypothesised that turanose was produced by enzymes from honeybees and performed a series of simulation experiments to prove this hypothesis. We found turanose in honey was produced by honeybees processing sucrose. Furthermore, we determined that sugar composition of simulated nectar influenced the turanose concentration in honey: when sucrose concentration was below 5%, turanose was difficult to form, whereas high concentration of fructose and limited glucose were beneficial in producing turanose. Using 13C-labelled sucrose tests combined with proteomics analysis, we identified that α-glucosidase converted sucrose to turanose through an intermolecular isomerisation process. This study reveals the formation mechanism of turanose in honey and assists in the scientific control and improvement of honey quality.
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Affiliation(s)
- Yuzhe Yuan
- State Key Laboratory of Resource Insects, Institute of Apiculture Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China
| | - Sha Yan
- College of Food Science and Engineering, Shanxi Agricultural University, Taigu 030801, China
| | - Liming Wu
- State Key Laboratory of Resource Insects, Institute of Apiculture Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China
| | - Haitao Xu
- State Key Laboratory of Resource Insects, Institute of Apiculture Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China
| | - Guodong Mu
- State Key Laboratory of Resource Insects, Institute of Apiculture Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China
| | - Xiaofeng Xue
- State Key Laboratory of Resource Insects, Institute of Apiculture Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China.
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2
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Liu Y, Dunker S, Durka W, Dominik C, Heuschele JM, Honchar H, Hoffmann P, Musche M, Paxton RJ, Settele J, Schweiger O. Eco-evolutionary processes shaping floral nectar sugar composition. Sci Rep 2024; 14:13856. [PMID: 38879632 PMCID: PMC11180116 DOI: 10.1038/s41598-024-64755-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 06/12/2024] [Indexed: 06/19/2024] Open
Abstract
Floral nectar sugar composition is assumed to reflect the nutritional demands and foraging behaviour of pollinators, but the relative contributions of evolutionary and abiotic factors to nectar sugar composition remain largely unknown across the angiosperms. We compiled a comprehensive dataset on nectar sugar composition for 414 insect-pollinated plant species across central Europe, along with phylogeny, paleoclimate, flower morphology, and pollinator dietary demands, to disentangle their relative effects. We found that phylogeny was strongly related with nectar sucrose content, which increased with the phylogenetic age of plant families, but even more strongly with historic global surface temperature. Nectar sugar composition was also defined by floral morphology, though it was not related to our functional measure of pollinator dietary demands. However, specialist pollinators of current plant-pollinator networks predominantly visited plant species with sucrose-rich nectar. Our results suggest that both physiological mechanisms related to plant water balance and evolutionary effects related to paleoclimatic changes have shaped floral nectar sugar composition during the radiation and specialisation of plants and pollinators. As a consequence, the high velocity of current climate change may affect plant-pollinator interaction networks due to a conflicting combination of immediate physiological responses and phylogenetic conservatism.
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Affiliation(s)
- Yicong Liu
- Department of Community Ecology, Helmholtz-Centre for Environmental Research-UFZ, Halle (Saale), Germany.
- Institute for Biology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany.
| | - Susanne Dunker
- Department of Physiological Diversity, Helmholtz-Centre for Environmental Research-UFZ, Leipzig, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Walter Durka
- Department of Community Ecology, Helmholtz-Centre for Environmental Research-UFZ, Halle (Saale), Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Christophe Dominik
- Department of Community Ecology, Helmholtz-Centre for Environmental Research-UFZ, Halle (Saale), Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Jonna M Heuschele
- Department of Community Ecology, Helmholtz-Centre for Environmental Research-UFZ, Halle (Saale), Germany
- Institute for Biology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
- Department of Biodiversity and People, German Centre for Integrative Biodiversity Research-Jena-Leipzig, Leipzig, Germany
| | - Hanna Honchar
- Department of Conservation Biology and Social-Ecological Systems, Helmholtz Centre for Environmental Research-UFZ, Halle (Saale), Germany
- Department of Ecological Monitoring, Institute for Evolutionary Ecology, NAS Ukraine, Kyiv, Ukraine
| | - Petra Hoffmann
- Department of Physiological Diversity, Helmholtz-Centre for Environmental Research-UFZ, Leipzig, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Martin Musche
- Department of Conservation Biology and Social-Ecological Systems, Helmholtz Centre for Environmental Research-UFZ, Halle (Saale), Germany
| | - Robert J Paxton
- Institute for Biology, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Josef Settele
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
- Department of Conservation Biology and Social-Ecological Systems, Helmholtz Centre for Environmental Research-UFZ, Halle (Saale), Germany
| | - Oliver Schweiger
- Department of Community Ecology, Helmholtz-Centre for Environmental Research-UFZ, Halle (Saale), Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
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3
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Tafi E, Sagona S, Meucci V, Bortolotti L, Galloni M, Bogo G, Gatta D, Casini L, Barberis M, Nepi M, Felicioli A. Effect of amino acid enriched diets on hemolymph amino acid composition in honey bees. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2024; 115:e22085. [PMID: 38288497 DOI: 10.1002/arch.22085] [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: 10/12/2023] [Revised: 12/21/2023] [Accepted: 01/10/2024] [Indexed: 02/01/2024]
Abstract
Amino acids (AAs) are an abundant class of nectar solutes, and they are involved in the nectar attractiveness to flower visitors. Among the various AAs, proline is the most abundant proteogenic AA, and γ-amino butyric acid (GABA) and β-alanine are the two most abundant non-proteogenic AAs. These three AAs are known to affect insect physiology, being involved in flight metabolism and neurotransmission. The aim of this study was to investigate the effects of artificial diets enriched with either β-alanine, GABA, or proline on consumption, survival, and hemolymph composition in honey bees belonging to two different ages and with different metabolism (i.e., newly emerged and foragers). Differences in feed intake among diets were not observed, while a diet enriched with β-alanine improved the survival rate of newly emerged honey bees compared to the control group. Variations in the hemolymph AA concentrations occurred only in newly emerged honey bees, according to the diet and the time of hemolymph sampling. A greater susceptibility of young honey bees to enriched diets than older honey bees was observed. The variations in the concentrations of hemolymph AAs reflect either the accumulation of dietary AAs or the existence of metabolic pathways that may lead to the conversion of dietary AAs into different ones. This investigation could be an initial contribution to studying the complex dynamics that regulate hemolymph AA composition and its effect on honey bee physiology.
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Affiliation(s)
- Elena Tafi
- Department of Veterinary Science, University of Pisa, Pisa, Italy
- CREA Research Centre for Agriculture and Environment, Bologna, Italy
| | - Simona Sagona
- Department of Veterinary Science, University of Pisa, Pisa, Italy
- Department of Pharmacy, University of Pisa, Pisa, Italy
| | - Valentina Meucci
- Department of Veterinary Science, University of Pisa, Pisa, Italy
| | - Laura Bortolotti
- CREA Research Centre for Agriculture and Environment, Bologna, Italy
| | - Marta Galloni
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Gherardo Bogo
- CREA Research Centre for Agriculture and Environment, Bologna, Italy
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Domenico Gatta
- Department of Veterinary Science, University of Pisa, Pisa, Italy
| | - Lucia Casini
- Department of Veterinary Science, University of Pisa, Pisa, Italy
| | - Marta Barberis
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Bologna, Italy
| | - Massimo Nepi
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Antonio Felicioli
- Department of Veterinary Science, University of Pisa, Pisa, Italy
- Interdepartmental Research Centre "Nutraceuticals and Food for Health", University of Pisa, Pisa, Italy
- Center for Research in Agricultural and Environmental Sciences "E. Avanzi", University of Pisa, Pisa, Italy
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4
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Göttlinger T, Lohaus G. Origin and Function of Amino Acids in Nectar and Nectaries of Pitcairnia Species with Particular Emphasis on Alanine and Glutamine. PLANTS (BASEL, SWITZERLAND) 2023; 13:23. [PMID: 38202331 PMCID: PMC10780904 DOI: 10.3390/plants13010023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/08/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024]
Abstract
Floral nectar contains sugars and numerous other compounds, including amino acids, but little is known about their function and origin in nectar. Therefore, the amino acid, sugar, and inorganic ion concentrations, as well as the activity of alanine aminotransferase (AlaAT) and glutamine synthetase (GS) in nectar, nectaries, and leaves were analyzed in 30 Pitcairnia species. These data were compared with various floral traits, the pollinator type, and the phylogenetic relationships of the species to find possible causes for the high amino acid concentrations in the nectar of some species. The highest concentrations of amino acids (especially alanine) in nectar were found in species with reddish flowers. Furthermore, the concentration of amino acids in nectar and nectaries is determined through analyzing flower color/pollination type rather than phylogenetic relations. This study provides new insights into the origin of amino acids in nectar. The presence of almost all amino acids in nectar is mainly due to their transport in the phloem to the nectaries, with the exception of alanine, which is partially produced in nectaries. In addition, active regulatory mechanisms are required in nectaries that retain most of the amino acids and allow the selective secretion of specific amino acids, such as alanine.
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Affiliation(s)
- Thomas Göttlinger
- Molecular Plant Science and Plant Biochemistry, University of Wuppertal, 42119 Wuppertal, Germany;
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5
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Brzosko E, Bajguz A, Burzyńska J, Chmur M. In Which Way Do the Flower Properties of the Specialist Orchid Goodyera repens Meet the Requirements of Its Generalist Pollinators? Int J Mol Sci 2023; 24:ijms24108602. [PMID: 37239948 DOI: 10.3390/ijms24108602] [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: 04/19/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
This article is the next part of a series of studies documenting the influence of flower traits on the reproductive success (RS) of orchids. Knowledge of factors influencing RS helps to understand the mechanisms and processes crucial for shaping plant-pollinator interactions. The aim of the present study was to determine the role of flower structure and nectar composition in shaping the RS of the specialist orchid Goodyea repens, which is pollinated by generalist bumblebees. We found a high level of pollinaria removal (PR) and female reproductive success (fruiting, FRS) as well as a high level of variation between populations, although in certain populations pollination efficiency was low. Floral display traits, mainly inflorescence length, influenced FRS in certain populations. Among the flower traits, only the height of flowers was correlated with FRS in one population, suggesting that the flower structure of this orchid is well adapted to pollination by bumblebees. The nectar of G. repens is diluted and dominated by hexoses. Sugars were less important in shaping RS than amino acids. At the species level, twenty proteogenic and six non-proteogenic AAs were noted, along with their differentiated amounts and participation in particular populations. We found that distinct AAs or their groups mainly shaped PR, especially when correlations were considered at the species level. Our results suggest that both the individual nectar components and the ratios between them have an impact on G. repens RS. Because different nectar components influence the RS parameters in different ways (i.e., negatively or positively), we suggest that different Bombus species play the role of main pollinators in distinct populations.
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Affiliation(s)
- Emilia Brzosko
- Department of Biology and Plant Ecology, Faculty of Biology, University of Bialystok, Ciolkowskiego 1J, 15-245 Bialystok, Poland
| | - Andrzej Bajguz
- Department of Biology and Plant Ecology, Faculty of Biology, University of Bialystok, Ciolkowskiego 1J, 15-245 Bialystok, Poland
| | - Justyna Burzyńska
- Department of Biology and Plant Ecology, Faculty of Biology, University of Bialystok, Ciolkowskiego 1J, 15-245 Bialystok, Poland
| | - Magdalena Chmur
- Department of Biology and Plant Ecology, Faculty of Biology, University of Bialystok, Ciolkowskiego 1J, 15-245 Bialystok, Poland
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6
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Lustofin K, Świątek P, Miranda VFO, Płachno BJ. Phylogenetical Position versus Pollination Syndromes: Floral Trichomes of Central American and Mexican Pinguicula. Int J Mol Sci 2023; 24:ijms24098423. [PMID: 37176130 PMCID: PMC10179228 DOI: 10.3390/ijms24098423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 04/27/2023] [Accepted: 04/29/2023] [Indexed: 05/15/2023] Open
Abstract
Central American and Mexican Pinguicula species are characterized by enormous divergence in size and color of flowers and are pollinated by butterflies, flies, bees, and hummingbirds. It is known that floral trichomes are key characters in plant-pollinator interaction. The main aim of our study was to verify our hypothesis that the distribution and diversity of non-glandular and glandular trichomes are related to the pollinator syndromes rather than the phylogenetic relationships. The studied sample consisted of Central American and Mexican species. In our study, we relied on light microscopy and scanning electron microscopy with a phylogenetic perspective based on ITS DNA sequences. The flower morphology of species pollinated by butterflies and hummingbirds was similar in contrast to species pollinated by flies and bees. Species pollinated by butterflies and hummingbirds contained low diversity of non-glandular trichomes, which occurred mostly in the tube and basal part of the spur. Surprisingly, in P. esseriana and P. mesophytica, non-glandular trichomes also occurred at the base of lower lip petals. In the case of species pollinated by flies/bees, we observed a high variety of non-glandular trichomes, which occurred on the surface of corolla petals, in the tube, and at the entrance to the spur. Furthermore, we did not identify any non-glandular trichomes in the spur. The capitate glandular trichomes were of similar morphology in all examined species. There were minor differences in the shape of the trichome head, as well as the length and the number of stalk cells. The distribution and the diversity of non-glandular and glandular trichomes and pollinator syndromes were mapped onto a phylogenetic reconstruction of the genus. Most micromorphological characters appear to be associated more with floral adaptation to pollinators and less with phylogeny.
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Affiliation(s)
- Krzysztof Lustofin
- Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University in Cracow, 9 Gronostajowa St., 30-387 Cracow, Poland
- Doctoral School of Exact and Natural Sciences, Jagiellonian University, 30-348 Cracow, Poland
| | - Piotr Świątek
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, 9 Bankowa St., 40-007 Katowice, Poland
| | - Vitor F O Miranda
- Laboratory of Plant Systematics, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal 14884-900, Brazil
| | - Bartosz J Płachno
- Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University in Cracow, 9 Gronostajowa St., 30-387 Cracow, Poland
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7
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Brzosko E, Bajguz A, Burzyńska J, Chmur M. Does Reproductive Success in Natural and Anthropogenic Populations of Generalist Epipactis helleborine Depend on Flower Morphology and Nectar Composition? Int J Mol Sci 2023; 24:4276. [PMID: 36901705 PMCID: PMC10001846 DOI: 10.3390/ijms24054276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 02/17/2023] [Accepted: 02/18/2023] [Indexed: 02/24/2023] Open
Abstract
The purpose of our study was to determine the role of flower structure and nectar composition in shaping the reproductive success (RS) of the generalist orchid Epipactis helleborine in natural and anthropogenic populations. We supposed that the distinct character of two groups of habitats creates different conditions for plant-pollinator relationships, thus influencing reproductive success in E. helleborine populations. Both pollinaria removal (PR) and fruiting (FRS) were differentiated between the populations. On average, FRS was almost two times higher in the anthropogenic than in the natural populations. The difference between the two population groups in PR was smaller but still statistically significant. RS parameters were correlated with some floral display and flower traits. Floral display influenced RS only in three anthropogenic populations. Flower traits had a weak influence on RS (10 of the 192 cases analyzed). The more important trait in shaping RS was nectar chemistry. The nectar of E. helleborine is relatively diluted with a lower sugar concentration in the anthropogenic than in the natural populations. In the natural populations, domination of sucrose over hexoses was found, while in the anthropogenic populations, hexoses were more abundant and the participation of sugars was balanced. In some populations, sugars influenced RS. In E. helleborine nectar, 20 proteogenic and 7 non-proteogenic amino acids (AAs) were found with a clear domination of glutamic acid. We noted relationships between some AAs and RS, but distinct AAs shaped RS in different populations, and their impact was independent of their participation. Our results indicate that the flower structure and nectar composition of E. helleborine reflect its generalistic character and meet the requirements of a wide range of pollinators. Simultaneously, the differentiation of flower traits suggests a variation in pollinator assemblages in particular populations. Knowledge about the factors influencing RS in distinct habitats helps to understand the evolutionary potential of species and to understand mechanisms and processes crucial for shaping interactions between plants and pollinators.
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Affiliation(s)
- Emilia Brzosko
- Department of Biology and Plant Ecology, Faculty of Biology, University of Bialystok, Ciolkowskiego 1J, 15-245 Bialystok, Poland
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8
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van der Niet T, Egan PA, Schlüter PM. Evolutionarily inspired solutions to the crop pollination crisis. Trends Ecol Evol 2023; 38:435-445. [PMID: 36737302 DOI: 10.1016/j.tree.2022.12.010] [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: 05/31/2022] [Revised: 12/16/2022] [Accepted: 12/21/2022] [Indexed: 02/04/2023]
Abstract
The global decline in insect diversity threatens pollination services, potentially impacting crop production and food security. Here, we argue that this looming pollination crisis is generally approached from an ecological standpoint, and that consideration of evolutionary principles offers a novel perspective. First, we outline that wild plant species have overcome 'pollination crises' throughout evolutionary history, and show how associated principles can be applied to crop pollination. We then highlight technological advances that can be used to adapt crop flowers for optimal pollination by local wild pollinators, especially by increasing generalization in pollination systems. Thus, synergies among fundamental evolutionary research, genetic engineering, and agro-ecological science provide a promising template for addressing a potential pollination crisis, complementing much-needed strategies focused on pollinator conservation.
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Affiliation(s)
- Timotheüs van der Niet
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, P. Bag X01, 3209, Scottsville, Pietermaritzburg, South Africa.
| | - Paul A Egan
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden
| | - Philipp M Schlüter
- Department of Plant Evolutionary Biology, Institute of Biology, University of Hohenheim, Garbenstraße 30, 70599 Stuttgart, Germany
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9
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Hewes AE, Cuban D, Groom DJE, Sargent AJ, Beltrán DF, Rico-Guevara A. Variable evidence for convergence in morphology and function across avian nectarivores. J Morphol 2022; 283:1483-1504. [PMID: 36062802 DOI: 10.1002/jmor.21513] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 08/20/2022] [Accepted: 08/24/2022] [Indexed: 01/19/2023]
Abstract
Nectar-feeding birds provide an excellent system in which to examine form-function relationships over evolutionary time. There are many independent origins of nectarivory in birds, and nectar feeding is a lifestyle with many inherent biophysical constraints. We review the morphology and function of the feeding apparatus, the locomotor apparatus, and the digestive and renal systems across avian nectarivores with the goals of synthesizing available information and identifying the extent to which different aspects of anatomy have morphologically and functionally converged. In doing so, we have systematically tabulated the occurrence of putative adaptations to nectarivory across birds and created what is, to our knowledge, the first comprehensive summary of adaptations to nectarivory across body systems and taxa. We also provide the first phylogenetically informed estimate of the number of times nectarivory has evolved within Aves. Based on this synthesis of existing knowledge, we identify current knowledge gaps and provide suggestions for future research questions and methods of data collection that will increase our understanding of the distribution of adaptations across bodily systems and taxa, and the relationship between those adaptations and ecological and evolutionary factors. We hope that this synthesis will serve as a landmark for the current state of the field, prompting investigators to begin collecting new data and addressing questions that have heretofore been impossible to answer about the ecology, evolution, and functional morphology of avian nectarivory.
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Affiliation(s)
- Amanda E Hewes
- Department of Biology, University of Washington, Seattle, Washington, USA.,Burke Museum of Natural History and Culture, Seattle, Washington, USA
| | - David Cuban
- Department of Biology, University of Washington, Seattle, Washington, USA.,Burke Museum of Natural History and Culture, Seattle, Washington, USA
| | - Derrick J E Groom
- Department of Biology, San Francisco State University, San Francisco, California, USA
| | - Alyssa J Sargent
- Department of Biology, University of Washington, Seattle, Washington, USA.,Burke Museum of Natural History and Culture, Seattle, Washington, USA
| | - Diego F Beltrán
- Department of Biology, University of Washington, Seattle, Washington, USA
| | - Alejandro Rico-Guevara
- Department of Biology, University of Washington, Seattle, Washington, USA.,Burke Museum of Natural History and Culture, Seattle, Washington, USA
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10
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Honey compositional convergence and the parallel domestication of social bees. Sci Rep 2022; 12:18280. [PMID: 36316374 PMCID: PMC9622900 DOI: 10.1038/s41598-022-23310-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 10/29/2022] [Indexed: 11/15/2022] Open
Abstract
Honey collection evolved from simple honey hunting to the parallel and independent domestication of different species of bees in various parts of the world. In this study, we investigate the extent to which the composition of Apis and stingless bee honeys has been a driver in the selection of different bee species for domestication in Mesoamerica (Mexico) and Asia (Thailand) using a sampling design that combines peak honey profiling by H1 NMR spectroscopy with the collection of honeys from domesticated and undomesticated bee species. Our results show that, independently of the region of the world considered, domesticated stingless bees produce honey whose compositional profiles differ from those of the non-domesticated species and exhibit more similarities towards honeys produced by the domesticated Apis species. Our results provide evidence for the first time that the search for natural sweeteners in the environment by our ancestors led to the parallel and independent domestication of social bees producing honeys with similar compositional profiles.
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11
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Nicolson SW. Sweet solutions: nectar chemistry and quality. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210163. [PMID: 35491604 PMCID: PMC9058545 DOI: 10.1098/rstb.2021.0163] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 11/07/2021] [Indexed: 12/22/2022] Open
Abstract
Nectar, the main floral reward for pollinators, varies greatly in composition and concentration. The assumption that nectar quality is equivalent to its sugar (energy) concentration is too simple. Diverse non-sugar components, especially amino acids and secondary metabolites, play various roles in nutrition and health of pollinators. Many nectar compounds have indirect effects by altering the foraging behaviour of pollinators or protecting them from disease. This review also emphasizes the water component of nectar, often ignored because of evaporative losses and difficulties in sampling small nectar volumes. Nectar properties vary with environmental factors, pollinator visits and microbial contamination. Pollination mutualisms depend on the ability of insect and vertebrate pollinators to cope with and benefit from the variation and diversity in nectar chemistry. This article is part of the theme issue 'Natural processes influencing pollinator health: from chemistry to landscapes'.
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Affiliation(s)
- Susan W. Nicolson
- Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa
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12
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Ballego-Campos I, Forzza RC, Paiva ÉAS. Extranuptial nectaries in bromeliads: a new record for Pitcairnia burchellii and perspectives for Bromeliaceae. Naturwissenschaften 2022; 109:28. [DOI: 10.1007/s00114-022-01799-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/13/2022] [Accepted: 04/19/2022] [Indexed: 11/30/2022]
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13
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Pachpor T, Sonne M, Bhatt A, Parkar K, Shahane S, Mestry P, Kulkarni S, Ogale H, Patwardhan A. Nectar Sugar Composition, Standing Nectar Crop and Floral Visitor Diversity of Three Endemic Plant Species from Western Ghats Biodiversity Hot-Spot of India. Chem Biodivers 2022; 19:e202200001. [PMID: 35578975 DOI: 10.1002/cbdv.202200001] [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: 01/01/2022] [Accepted: 05/06/2022] [Indexed: 11/11/2022]
Abstract
Plant insect interactions are governed by various factors. Nectar availability and floral nectar composition play a significant role in deciding the pollinator pool that visits a particular plant species. This study investigates nectar sugar composition and volume from three endemic species from Western Ghats of India viz. Canthium dicoccum (Gaertn.) Teijsm. & Binn., Ligustrum perrottetii A. DC., and Wendlandia thyrsoidea (Roth) Steud., in their natural habitats. Our results demonstrate intraspecific variation in nectar sugar composition in these endemic plant species. Fructose, mannose and glucose sugars were found in the nectar of all three species. In addition to these three, arabinose was found in Ligustrum and sucrose in Canthium. Nectar volume showed variations in bagged and unbagged conditions. The highest average nectar quantity was found in Canthium (1.27 μl/flower), followed by Ligustrum (0. 31 μl/flower), and Wendlandia (0.14 μl/flower). Floral visitor diversity with a specific emphasis on butterflies showed the highest number of visitors on Ligustrum i. e., 42 out of 45 total butterfly species across all three plant species. This is the first report of standing nectar crop and nectar-sugar composition data compiled for these plant species.
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Affiliation(s)
- Tejaswini Pachpor
- Annasaheb Kulkarni Department of Biodiversity, M.E.S. Abasaheb Garware College, Pune-411004, Maharashtra, India
| | - Mrunalini Sonne
- Annasaheb Kulkarni Department of Biodiversity, M.E.S. Abasaheb Garware College, Pune-411004, Maharashtra, India
| | - Alap Bhatt
- Annasaheb Kulkarni Department of Biodiversity, M.E.S. Abasaheb Garware College, Pune-411004, Maharashtra, India
| | - Kshitija Parkar
- Annasaheb Kulkarni Department of Biodiversity, M.E.S. Abasaheb Garware College, Pune-411004, Maharashtra, India
| | - Sneha Shahane
- Annasaheb Kulkarni Department of Biodiversity, M.E.S. Abasaheb Garware College, Pune-411004, Maharashtra, India
| | - Pratiksha Mestry
- Annasaheb Kulkarni Department of Biodiversity, M.E.S. Abasaheb Garware College, Pune-411004, Maharashtra, India
| | - Shivani Kulkarni
- Annasaheb Kulkarni Department of Biodiversity, M.E.S. Abasaheb Garware College, Pune-411004, Maharashtra, India
| | - Hemant Ogale
- Research and Action in Natural Wealth Administration (RANWA), 16 Swastishree Society, Ganeshnagar, Kothrud, Pune - 411052, Maharashtra, India
| | - Ankur Patwardhan
- Annasaheb Kulkarni Department of Biodiversity, M.E.S. Abasaheb Garware College, Pune-411004, Maharashtra, India.,Research and Action in Natural Wealth Administration (RANWA), 16 Swastishree Society, Ganeshnagar, Kothrud, Pune - 411052, Maharashtra, India
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14
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Mehltreter K, Tenhaken R, Jansen S. Nectaries in ferns: their taxonomic distribution, structure, function, and sugar composition. AMERICAN JOURNAL OF BOTANY 2022; 109:46-57. [PMID: 34643269 DOI: 10.1002/ajb2.1781] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 09/29/2021] [Accepted: 10/01/2021] [Indexed: 06/13/2023]
Abstract
PREMISE Extrafloral nectaries have mainly been studied in angiosperms, but have also been reported in 39 fern species. Here we provide a global review of nectaries in ferns and examined their structure, function, and nectar sugar composition in two genera. METHODS We searched in the literature and living plant collections of botanical gardens for indications of fern nectaries, observed nectar-feeding animals, studied the morphoanatomy in the two genera Aglaomorpha and Campyloneurum, and analyzed the total sugar concentrations and ratios of 16 species. Diurnal nectar release was observed with time-lapse photography. RESULTS We found evidence for nectaries in 101 species of ferns from 11 genera and 6 families. Most of the nectary-bearing species were tree ferns (Cyatheaceae) and epiphytic ferns of the family Polypodiaceae. Nectaries consisted of cytoplasm-rich parenchyma with large nuclei and an epidermis with or without stomata, were attached to amphiphloic vascular bundles, and released nectar on the lower leaf surface mainly on expanding leaves during the night. Sugar concentrations varied between species (3.8-15.3%) but not between genera, and were sucrose-dominant (3 spp.), sucrose-rich (7), or hexose-rich (3). In the greenhouse, introduced ants, scale insects, and snails fed on the nectar. CONCLUSIONS The wide taxonomic distribution, variable morphology, locations, and sugar compositions point to multiple evolutionary origins of fern nectaries. Nectar release in young leaves might attract mutualistic ants to protect leaves against herbivores only during this most vulnerable developmental stage. Even ex-situ, fern nectar is a valuable food source because it attracted several opportunistic animal species.
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Affiliation(s)
- Klaus Mehltreter
- Red de Ecología Funcional, Instituto de Ecología, A.C., Carretera antigua a Coatepec No. 351, El Haya, Xalapa, 91073, México
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, Ulm, 89081, Germany
| | - Raimund Tenhaken
- Department of Cell Biology, University of Salzburg, Hellbrunnerstr. 34, Salzburg, 5020, Austria
| | - Steven Jansen
- Institute of Systematic Botany and Ecology, Ulm University, Albert-Einstein-Allee 11, Ulm, 89081, Germany
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Karimi N, Saghafi S, Keefover‐Ring K, Venter SM, Ané C, Baum DA. Evidence for hawkmoth pollination in the chiropterophilous African baobab (
Adansonia digitata
). Biotropica 2021. [DOI: 10.1111/btp.13033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nisa Karimi
- Department of Botany University of Wisconsin‐Madison Madison Wisconsin USA
| | - Samuel Saghafi
- Department of Botany University of Wisconsin‐Madison Madison Wisconsin USA
- Department of Medicine University of Wisconsin‐Madison Madison Wisconsin USA
| | - Ken Keefover‐Ring
- Department of Botany University of Wisconsin‐Madison Madison Wisconsin USA
- Department of Geography University of Wisconsin‐Madison Madison Wisconsin USA
| | - Sarah M. Venter
- School of Animal, Plant and Environmental Sciences University of the Witwatersrand Johannesburg South Africa
| | - Cécile Ané
- Department of Botany University of Wisconsin‐Madison Madison Wisconsin USA
- Department of Statistics University of Wisconsin‐Madison Madison Wisconsin USA
| | - David A. Baum
- Department of Botany University of Wisconsin‐Madison Madison Wisconsin USA
- Wisconsin Institute for Discovery Madison Wisconsin USA
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16
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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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17
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Brzosko E, Mirski P. Floral Nectar Chemistry in Orchids: A Short Review and Meta-Analysis. PLANTS (BASEL, SWITZERLAND) 2021; 10:2315. [PMID: 34834677 PMCID: PMC8620889 DOI: 10.3390/plants10112315] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 10/21/2021] [Accepted: 10/23/2021] [Indexed: 05/12/2023]
Abstract
Nectar is one of the most important flower traits, shaping plant-pollinator interactions and reproductive success. Despite Orchidaceae including numerous nectariferous species, nectar chemistry in this family has been infrequently studied. Therefore, the aim of this study is to compile data about nectar attributes in different orchid species. The scarcity of data restricted analyses to sugar concentration and composition. Our results suggest that the most important factor shaping nectar traits in orchids is the pollinator type, although we also found differentiation of nectar traits according to geographical regions. In spurred orchids, the length of the spur impacted nectar traits. We recommend the development of studies on nectar chemistry in orchids, including a wider range of species (both in taxonomic and geographical contexts), as well as extending the analyses to other nectar components (such as amino acids and secondary metabolites). The nectar biome would be also worth investigating, since it could affect the chemical composition of nectar. This will enrich the understanding of the mechanisms of plants-pollinators interactions.
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Affiliation(s)
- Emilia Brzosko
- Faculty of Biology, University of Bialystok, Ciołkowskiego 1J, 15-245 Bialystok, Poland
| | - Paweł Mirski
- Faculty of Biology, University of Bialystok, Ciołkowskiego 1J, 15-245 Bialystok, Poland
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18
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Bilbao G, Bruneau A, Joly S. Judge it by its shape: a pollinator-blind approach reveals convergence in petal shape and infers pollination modes in the genus Erythrina. AMERICAN JOURNAL OF BOTANY 2021; 108:1716-1730. [PMID: 34590308 DOI: 10.1002/ajb2.1735] [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: 11/11/2020] [Accepted: 05/12/2021] [Indexed: 06/13/2023]
Abstract
PREMISE Pollinators are thought to exert selective pressures on plants, mediating the evolution of convergent floral shape often recognized as pollination syndromes. However, little is known about the accuracy of using petal shape for inferring convergence in pollination mode without a priori pollination information. Here we studied the genus Erythrina L. as a test case to assess whether ornithophyllous pollination modes (hummingbirds, passerines, sunbirds, or mixed pollination) can be inferred based on the evolutionary analysis of petal shape. METHODS We characterized the two-dimensional dissected shape of standard, keel, and wing petals from 106 Erythrina species using geometric morphometrics and reconstructed a phylogenetic tree of 83 Erythrina species based on plastid trnL-F and nuclear ribosomal ITS sequences. We then used two phylogenetic comparative methods based on Ornstein-Uhlenbeck models, SURFACE and l1OU, to infer distinct morphological groups using petal shape and identify instances of convergent evolution. The effectiveness of these methods was evaluated by comparing the groups inferred to known pollinators. RESULTS We found significant petal shape differences between hummingbird- and passerine-pollinated Erythrina species. Our analyses also revealed that petal combinations generally provided better inferences of pollinator types than individual petals and that the method and optimization criterion can affect the results. CONCLUSIONS We show that model-based approaches using petal shape can detect convergent evolution of floral shape and relatively accurately infer pollination modes in Erythrina. The inference power of the keel petals argues for a deeper investigation of their role in the pollination biology of Erythrina and other bird-pollinated legumes.
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Affiliation(s)
- Gonzalo Bilbao
- Institut de recherche en biologie végétale and Département de Sciences biologiques, Université de Montréal, 4101 Sherbrooke East, Montréal (QC), H1X 2B2, Canada
| | - Anne Bruneau
- Institut de recherche en biologie végétale and Département de Sciences biologiques, Université de Montréal, 4101 Sherbrooke East, Montréal (QC), H1X 2B2, Canada
| | - Simon Joly
- Institut de recherche en biologie végétale and Département de Sciences biologiques, Université de Montréal, 4101 Sherbrooke East, Montréal (QC), H1X 2B2, Canada
- Montreal Botanical Garden, 4101 Sherbrooke East, Montréal (QC), H1X 2B2, Canada
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19
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McWhorter TJ, Rader JA, Schondube JE, Nicolson SW, Pinshow B, Fleming PA, Gutiérrez-Guerrero YT, Martínez Del Rio C. Sucrose digestion capacity in birds shows convergent coevolution with nectar composition across continents. iScience 2021; 24:102717. [PMID: 34235412 PMCID: PMC8246590 DOI: 10.1016/j.isci.2021.102717] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 05/21/2021] [Accepted: 06/08/2021] [Indexed: 12/23/2022] Open
Abstract
The major lineages of nectar-feeding birds (hummingbirds, sunbirds, honeyeaters, flowerpiercers, and lorikeets) are considered examples of convergent evolution. We compared sucrose digestion capacity and sucrase enzymatic activity per unit intestinal surface area among 50 avian species from the New World, Africa, and Australia, including 20 nectarivores. With some exceptions, nectarivores had smaller intestinal surfaces, higher sucrose hydrolysis capacity, and greater sucrase activity per unit intestinal area. Convergence analysis showed high values for sucrose hydrolysis and sucrase activity per unit intestinal surface area in specialist nectarivores, matching the high proportion of sucrose in the nectar of the plants they pollinate. Plants pollinated by generalist nectar-feeding birds in the Old and New Worlds secrete nectar in which glucose and fructose are the dominant sugars. Matching intestinal enzyme activity in birds and nectar composition in flowers appears to be an example of convergent coevolution between plants and pollinators on an intercontinental scale. Nectarivory has evolved independently in birds in the New and Old Worlds Nectarivorous birds have greater sucrose hydrolysis capacity than nonspecialists Nectarivorous birds have a smaller intestinal surface area than nonspecialists Capacity to digest sucrose and high nectar sucrose content coevolved independently
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Affiliation(s)
- Todd J McWhorter
- School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy Campus, SA 5371, Australia
| | - Jonathan A Rader
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3280, USA
| | - Jorge E Schondube
- Centro de Investigaciones en Ecosistemas, Universidad Nacional Autónoma de México campus Morelia, Morelia, Michoacán CP 58190, México
| | - Susan W Nicolson
- Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa
| | - Berry Pinshow
- Mitrani Department of Desert Ecology, Swiss Institute for Dryland Environmental and Energy Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, 8499000 Midreshet Ben-Gurion, Israel
| | - Patricia A Fleming
- Environmental and Conservation Sciences, Harry Butler Institute, Murdoch University, Murdoch, WA 6150, Australia
| | - Yocelyn T Gutiérrez-Guerrero
- Departamento de Biología Evolutiva, Instituto de Ecología, Universidad Nacional Autonoma de México, Mexico D.F., México
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20
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Janeček Š, Chmel K, Ewome FL, Hrubá K, Klomberg Y, Kobe IN, Kouede RD, Mertens JEJ, Njie MM, Tropek R. Differences in Nectar Traits between Ornithophilous and Entomophilous Plants on Mount Cameroon. PLANTS (BASEL, SWITZERLAND) 2021; 10:1161. [PMID: 34200999 PMCID: PMC8226534 DOI: 10.3390/plants10061161] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 06/02/2021] [Accepted: 06/03/2021] [Indexed: 11/24/2022]
Abstract
Despite a growing number of studies, the role of pollinators as a selection agent for nectar traits remains unclear. Moreover, the lack of data from some biogeographic regions prohibits us from determining their general importance and global patterns. We analyzed nectar carbohydrate traits and determined the main pollinators of 66 plant species in the tropical forests of Mount Cameroon (tropical West Africa). The measured nectar traits included total sugar amounts and proportions of sucrose and hexoses (i.e., glucose and fructose). We report the nectar properties for plants visited by five pollinator groups (bees, butterflies, moths, hoverflies, and specialized birds). Our results indicate that, rather than specific evolution in each of the five plant groups, there was a unique nectar-trait evolution in plants pollinated by specialized birds. The ornithophilous plants had a higher proportion of sucrose and produced larger sugar amounts than the plants pollinated by insects. We also demonstrated a significant phylogenetic signal in the nectar properties in some lineages of the studied plants.
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Affiliation(s)
- Štěpán Janeček
- Department of Ecology, Faculty of Science, Charles University, Viničná 7, CZ-128 44 Prague 2, Czech Republic; (K.C.); (Y.K.); (I.N.K.); (J.E.J.M.); (R.T.)
| | - Kryštof Chmel
- Department of Ecology, Faculty of Science, Charles University, Viničná 7, CZ-128 44 Prague 2, Czech Republic; (K.C.); (Y.K.); (I.N.K.); (J.E.J.M.); (R.T.)
- Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-370 05 České Budějovice, Czech Republic;
| | | | - Karolína Hrubá
- Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-370 05 České Budějovice, Czech Republic;
- Department of Zoology, Faculty of Sciences, University of South Bohemia, Branišovská 1760, CZ-370 05 České Budějovice, Czech Republic
| | - Yannick Klomberg
- Department of Ecology, Faculty of Science, Charles University, Viničná 7, CZ-128 44 Prague 2, Czech Republic; (K.C.); (Y.K.); (I.N.K.); (J.E.J.M.); (R.T.)
- Naturalis Biodiversity Center, Darwinweg 2, 2233 CR Leiden, The Netherlands
| | - Ishmeal N. Kobe
- Department of Ecology, Faculty of Science, Charles University, Viničná 7, CZ-128 44 Prague 2, Czech Republic; (K.C.); (Y.K.); (I.N.K.); (J.E.J.M.); (R.T.)
| | - Raissa Dywou Kouede
- Department of Nursing, Faculty of Health Science, Herzing University, 1865 SR 436, Winter Park, Orlando, FL 32792, USA;
| | - Jan E. J. Mertens
- Department of Ecology, Faculty of Science, Charles University, Viničná 7, CZ-128 44 Prague 2, Czech Republic; (K.C.); (Y.K.); (I.N.K.); (J.E.J.M.); (R.T.)
| | - Marcus Mokake Njie
- Department of Zoology and Animal Physiology, Faculty of Science, University of Buea, Buea 63, Cameroon;
| | - Robert Tropek
- Department of Ecology, Faculty of Science, Charles University, Viničná 7, CZ-128 44 Prague 2, Czech Republic; (K.C.); (Y.K.); (I.N.K.); (J.E.J.M.); (R.T.)
- Biology Centre, Czech Academy of Sciences, Branišovská 31, CZ-370 05 České Budějovice, Czech Republic;
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21
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Evolutionary and Ecological Considerations on Nectar-Mediated Tripartite Interactions in Angiosperms and Their Relevance in the Mediterranean Basin. PLANTS 2021; 10:plants10030507. [PMID: 33803275 PMCID: PMC7999006 DOI: 10.3390/plants10030507] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 02/22/2021] [Accepted: 03/03/2021] [Indexed: 11/16/2022]
Abstract
The Mediterranean basin hosts a high diversity of plants and bees, and it is considered one of the world's biodiversity hotspots. Insect pollination, i.e., pollen transfer from male reproductive structures to conspecific female ones, was classically thought to be a mutualistic relationship that links these two groups of organisms, giving rise to an admirable and complex network of interactions. Although nectar is often involved in mediating these interactions, relatively little is known about modifications in its chemical traits during the evolution of plants. Here, we examine how the current sucrose-dominated floral nectar of most Mediterranean plants could have arisen in the course of evolution of angiosperms. The transition from hexose-rich to sucrose-rich nectar secretion was probably triggered by increasing temperature and aridity during the Cretaceous period, when most angiosperms were radiating. This transition may have opened new ecological niches for new groups of insects that were co-diversifying with angiosperms and for specific nectar-dwelling yeasts that originated later (i.e., Metschnikowiaceae). Our hypothesis embeds recent discoveries in nectar biology, such as the involvement of nectar microbiota and nectar secondary metabolites in shaping interactions with pollinators, and it suggests a complex, multifaceted ecological and evolutionary scenario that we are just beginning to discover.
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22
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Keller B, Ganz R, Mora-Carrera E, Nowak MD, Theodoridis S, Koutroumpa K, Conti E. Asymmetries of reproductive isolation are reflected in directionalities of hybridization: integrative evidence on the complexity of species boundaries. THE NEW PHYTOLOGIST 2021; 229:1795-1809. [PMID: 32761901 DOI: 10.1111/nph.16849] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 07/23/2020] [Indexed: 05/26/2023]
Abstract
The complex nature of species boundaries has been a central topic in evolutionary biology ever since Darwin. Despite numerous separate studies on reproductive isolation and hybridization, their relationship remains underinvestigated. Are the strengths and asymmetries of reproductive barriers reflected in the extent and directionalities of interspecific genetic exchange? We combined field, experimental, and molecular data to quantify strengths and asymmetries of sympatric reproductive barriers and hybridization between florally heteromorphic primroses. We also assessed whether generalist pollinators discriminate between different floral cues and contribute to reproductive isolation, a long-debated topic. Sympatric reproductive isolation is high but incomplete, and most phenotypic intermediates are genetic F1 hybrids, whereas backcrosses are rare, revealing low interspecific gene flow. Species integrity rests on multiple barriers, but ethological isolation is among the strongest, demonstrating that even generalist pollinators crucially contribute to the maintenance of species boundaries. Furthermore, reproductive barriers are weaker for Primula veris and short-styled plants, results corroborated by molecular data. Thus, in florally heteromorphic systems, both species- and morph-dependent asymmetries affect permeability of species boundaries. Our study illustrates how the interactions between complex floral syndromes and pollinators shape species boundaries in unique, previously undescribed ways.
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Affiliation(s)
- Barbara Keller
- Department of Systematic and Evolutionary Botany, University of Zurich, Zollikerstrasse 107, Zurich, 8008, Switzerland
| | - Rita Ganz
- Department of Systematic and Evolutionary Botany, University of Zurich, Zollikerstrasse 107, Zurich, 8008, Switzerland
| | - Emiliano Mora-Carrera
- Department of Systematic and Evolutionary Botany, University of Zurich, Zollikerstrasse 107, Zurich, 8008, Switzerland
| | - Michael D Nowak
- Department of Systematic and Evolutionary Botany, University of Zurich, Zollikerstrasse 107, Zurich, 8008, Switzerland
| | - Spyros Theodoridis
- Department of Systematic and Evolutionary Botany, University of Zurich, Zollikerstrasse 107, Zurich, 8008, Switzerland
| | - Konstantina Koutroumpa
- Department of Systematic and Evolutionary Botany, University of Zurich, Zollikerstrasse 107, Zurich, 8008, Switzerland
| | - Elena Conti
- Department of Systematic and Evolutionary Botany, University of Zurich, Zollikerstrasse 107, Zurich, 8008, Switzerland
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Paiva ÉAS, Ballego-Campos I, Gibernau M. True nectar or stigmatic secretion? Structural evidence elucidates an old controversy regarding nectaries in Anthurium. AMERICAN JOURNAL OF BOTANY 2021; 108:37-50. [PMID: 33449391 DOI: 10.1002/ajb2.1595] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 09/14/2020] [Indexed: 06/12/2023]
Abstract
PREMISE Floral rewards are essential in understanding floral function and evolution of the relationships between flowers and pollinators. Whether sugars are present in stigmatic exudates in Anthurium and whether it has floral nectaries have remained controversial because of the scarcity of structural studies. To solve these questions, we investigated the floral anatomy of A. andraeanum to elucidate whether (1) tepals are secretory organs, (2) tepals possess a structurally recognizable nectary, and (3) tepalar secretion differs from stigmatic secretion. METHODS Floral structure was assessed through light and electron microscopy of samples of immature, pistillate, and staminate flowers. The dynamics of the starch reserve was investigated using histochemical tests, and the sugar content in the floral exudates was assessed using thin-layer chromatography. RESULTS Sugar analysis did not detect sucrose, glucose, or fructose in stigmatic secretions, but confirmed their presence in tepalar secretions. Stigmatic secretion was produced by secretory stigmatic papillae; tepalar exudates were produced by nonvascularized nectaries in the apex of tepals. These nectaries were characterized by modified stomata and cells with cytoplasm rich in organelles, and a high content of calcium oxalate crystals. CONCLUSIONS Our results showed for the first time nectaries on tepals and true nectar secretion for A. andraeanum. Stigmatic secretion appears to be a distinct substance, and its often-reported sugar content seems to be a result of sample contamination. Nectar and stigmatic secretions have been often mistaken in other Anthurium species and deserve a revision for this genus.
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Affiliation(s)
- Élder Antônio Sousa Paiva
- Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, MG, Brazil
| | - Igor Ballego-Campos
- Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, MG, Brazil
| | - Marc Gibernau
- CNRS, University of Corsica Pascal Paoli, UMR 6134 SPE, Equipe Chimie et Biomasse, Route des Sanguinaires - Vignola, 20000, Ajaccio, France
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Lustofin K, Świątek P, Stolarczyk P, Miranda VFO, Płachno BJ. Do food trichomes occur in Pinguicula (Lentibulariaceae) flowers? ANNALS OF BOTANY 2020; 126:1039-1048. [PMID: 32592586 PMCID: PMC7596368 DOI: 10.1093/aob/mcaa123] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 06/19/2020] [Indexed: 05/27/2023]
Abstract
BACKGROUND AND AIMS Floral food bodies (including edible trichomes) are a form of floral reward for pollinators. This type of nutritive reward has been recorded in several angiosperm families: Annonaceae, Araceae, Calycanthaceae, Eupomatiaceae, Himantandraceae, Nymphaeaceae, Orchidaceae, Pandanaceae and Winteraceae. Although these bodies are very diverse in their structure, their cells contain food material: starch grains, protein bodies or lipid droplets. In Pinguicula flowers, there are numerous multicellular clavate trichomes. Previous authors have proposed that these trichomes in the Pinguicula flower play the role of 'futterhaare' ('feeding hairs') and are eaten by pollinators. The main aim of this study was to investigate whether the floral non-glandular trichomes of Pinguicula contain food reserves and thus are a reward for pollinators. The trichomes from the Pinguicula groups, which differ in their taxonomy (species from the subgenera: Temnoceras, Pinguicula and Isoloba) as well as the types of their pollinators (butterflies/flies and bees/hummingbirds), were examined. Thus, it was determined whether there are any connections between the occurrence of food trichomes and phylogeny position or pollination biology. Additionally, we determined the phylogenetic history of edible trichomes and pollinator evolution in the Pinguicula species. METHODS The species that were sampled were: Pinguicula moctezumae, P. esseriana, P. moranensis, P. emarginata, P. rectifolia, P. mesophytica, P. hemiepiphytica, P. agnata, P. albida, P. ibarrae, P. martinezii, P. filifolia, P. gigantea, P. lusitanica, P. alpina and P. vulgaris. Light microscopy, histochemistry, and scanning and transmission electron microscopy were used to address our aims with a phylogenetic perspective based on matK/trnK DNA sequences. KEY RESULTS No accumulation of protein bodies or lipid droplets was recorded in the floral non-glandular trichomes of any of the analysed species. Starch grains occurred in the cells of the trichomes of the bee-/fly-pollinated species: P. agnata, P. albida, P. ibarrae, P. martinezii, P. filifolia and P. gigantea, but not in P. alpina or P. vulgaris. Moreover, starch grains were not recorded in the cells of the trichomes of the Pinguicula species that have long spurs, which are pollinated by Lepidoptera (P. moctezumae, P. esseriana, P. moranensis, P. emarginata and P. rectifolia) or birds (P. mesophytica and P. hemiepihytica), or in species with a small and whitish corolla that self-pollinate (P. lusitanica). The results on the occurrence of edible trichomes and pollinator syndromes were mapped onto a phylogenetic reconstruction of the genus. CONCLUSION Floral non-glandular trichomes play the role of edible trichomes in some Pinguicula species (P. agnata, P. albida, P. ibarrae, P. martinezii, P. filifolia and P. gigantea), which are mainly classified as bee-pollinated species that had originated from Central and South America. It seems that in the Pinguicula that are pollinated by other pollinator groups (Lepidoptera and hummingbirds), the non-glandular trichomes in the flowers play a role other than that of a floral reward for their pollinators. Edible trichomes are symplesiomorphic for the Pinguicula species, and thus do not support a monophyletic group such as a synapomorphy. Nevertheless, edible trichomes are derived and are possibly a specialization for fly and bee pollinators by acting as a food reward for these visitors.
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Affiliation(s)
- Krzysztof Lustofin
- Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University in Kraków, 9 Gronostajowa Street, 30-387 Cracow, Poland
| | - Piotr Świątek
- Institute of Biology, Biotechnology and Environmental Protection, Faculty of Natural Sciences, University of Silesia in Katowice, 9 Bankowa Street, 40-007 Katowice, Poland
| | - Piotr Stolarczyk
- Unit of Botany and Plant Physiology, Institute of Plant Biology and Biotechnology, University of Agriculture in Kraków, 29 Listopada 54 Street, 31-425 Kraków, Poland
| | - Vitor F O Miranda
- Universidade Estadual Paulista (Unesp), Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal, Departamento de Biologia Aplicada à Agropecuária, São Paulo, Brazil
| | - Bartosz J Płachno
- Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University in Kraków, 9 Gronostajowa Street, 30-387 Cracow, Poland
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Hobson KA, García-Rubio OR, Carrera-Treviño R, Anparasan L, Kardynal KJ, McNeil JN, García-Serrano E, Mora Alvarez BX. Isotopic (δ2H) Analysis of Stored Lipids in Migratory and Overwintering Monarch Butterflies (Danaus plexippus): Evidence for Southern Critical Late-Stage Nectaring Sites? Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.572140] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Intraspecific Variation in Nectar Chemistry and Its Implications for Insect Visitors: The Case of the Medicinal Plant, Polemonium Caeruleum L. PLANTS 2020; 9:plants9101297. [PMID: 33019586 PMCID: PMC7600102 DOI: 10.3390/plants9101297] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/25/2020] [Accepted: 09/28/2020] [Indexed: 11/17/2022]
Abstract
Floral nectar, being a primary reward for insect visitors, is a key factor in shaping plant–pollinator interactions. However, little is known about the variability in nectar traits, which could potentially affect pollinators and the reproduction of the species. We investigated intraspecific variation in nectar traits in 14 populations of a Red-listed plant, Polemonium caeruleum. Populations varied in terms of the proportion of self-compatible and self-incompatible individuals, and insect communities visiting flowers. Using HPLC, we determined the nectar sugar and amino acid (AA) composition and concentration. We also recorded some basic habitat parameters, which could influence nectar chemistry. In seven selected populations, we investigated the taxonomic composition of the insects visiting flowers. Our observations revealed significant intraspecific variability in nectar chemistry in P. caeruleum. Nectar production was male-biased, with male-phase flowers secreting sucrose- and AA-rich nectar. An analysis revealed that variability in P. caeruleum nectar may be slightly shaped by environmental factors. The studied nectar characters, especially sugars, had little effect on insects visiting flowers. We argue that variation in nectar traits in this generalist plant is a matter of random genetic drift or “adaptive wandering” rather than directional specialization and adaptation in the most effective and abundant group of pollinators.
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Janeček Š, Chmel K, Uceda Gómez G, Janečková P, Chmelová E, Sejfová Z, Luma Ewome F. Ecological fitting is a sufficient driver of tight interactions between sunbirds and ornithophilous plants. Ecol Evol 2020; 10:1784-1793. [PMID: 32128116 PMCID: PMC7042734 DOI: 10.1002/ece3.5942] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 11/22/2019] [Accepted: 11/28/2019] [Indexed: 11/11/2022] Open
Abstract
Plant-bird pollination interactions evolved independently on different continents. Specific adaptations can lead to their restriction when potential partners from distant evolutionary trajectories come into contact. Alternatively, these interactions can be enabled by convergent evolution and subsequent ecological fitting.We studied the interactions between New World plants from the genus Heliconia, Asian plants of genus Etlingera and African sunbirds on a local farm in Cameroon. Heliconia spp. evolved together with hummingbirds and Etlingera spp. with spiderhunters -an oriental subgroup of the sunbird family.Sunbirds fed on all studied plants and individual plant species were visited by a different sunbird spectrum. We experimentally documented a higher number of germinated pollen grains in sunbird-visited flowers of Etlingera spp. For Heliconia spp., this experiment was not successful and pollen tubes were rarely observed, even in hand-pollinated flowers, where enough pollen was deposited. The analyses of contacts with plant reproductive organs nevertheless confirmed that sunbirds are good pollen vectors for both Heliconia and Etlingera species.Our study demonstrated a high ecological fit between actors of distinct evolutionary history and the general validity of bird-pollination syndrome. We moreover show that trait matching and niche differentiation are important ecological processes also in semi-artificial plant-pollinator systems.
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Affiliation(s)
- Štěpán Janeček
- Department of EcologyFaculty of ScienceCharles University in PraguePrahaCzech Republic
| | - Kryštof Chmel
- Department of EcologyFaculty of ScienceCharles University in PraguePrahaCzech Republic
- Biology CentreCzech Academy of SciencesČeské BudějoviceCzech Republic
| | - Guillermo Uceda Gómez
- Department of EcologyFaculty of ScienceCharles University in PraguePrahaCzech Republic
| | - Petra Janečková
- Department of EcologyFaculty of ScienceCharles University in PraguePrahaCzech Republic
- University of South BohemiaČeské BudějoviceCzech Republic
| | - Eliška Chmelová
- Department of EcologyFaculty of ScienceCharles University in PraguePrahaCzech Republic
- Biology CentreCzech Academy of SciencesČeské BudějoviceCzech Republic
| | - Zuzana Sejfová
- Department of EcologyFaculty of ScienceCharles University in PraguePrahaCzech Republic
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Lustofin K, Świątek P, Miranda VFO, Płachno BJ. Flower nectar trichome structure of carnivorous plants from the genus butterworts Pinguicula L. (Lentibulariaceae). PROTOPLASMA 2020; 257:245-259. [PMID: 31428856 PMCID: PMC6982637 DOI: 10.1007/s00709-019-01433-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Accepted: 08/07/2019] [Indexed: 05/22/2023]
Abstract
Pinguicula (Lentibulariaceae) is a genus comprising around 96 species of herbaceous, carnivorous plants, which are extremely diverse in flower size, colour and spur length and structure as well as pollination strategy. In Pinguicula, nectar is formed in the flower spur; however, there is a gap in the knowledge about the nectary trichome structure in this genus. Our aim was to compare the nectary trichome structure of various Pinguicula species in order to determine whether there are any differences among the species in this genus. The taxa that were sampled were Pinguicula moctezumae, P. moranensis, P. rectifolia, P. emarginata and P. esseriana. We used light microscopy, histochemistry, scanning and transmission electron microscopy to address those aims. We show a conservative nectary trichome structure and spur anatomy in various Mexican Pinguicula species. The gross structural similarities between the examined species were the spur anatomy, the occurrence of papillae, the architecture of the nectary trichomes and the ultrastructure characters of the trichome cells. However, there were some differences in the spur length, the size of spur trichomes, the occurrence of starch grains in the spur parenchyma and the occurrence of cell wall ingrowths in the terminal cells of the nectary trichomes. Similar nectary capitate trichomes, as are described here, were recorded in the spurs of species from other Lentibulariaceae genera. There are many ultrastructural similarities between the cells of nectary trichomes in Pinguicula and Utricularia.
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Affiliation(s)
- Krzysztof Lustofin
- Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University in Kraków, 9 Gronostajowa St, 30-387, Kraków, Poland
| | - Piotr Świątek
- Department of Animal Histology and Embryology, University of Silesia in Katowice, 9 Bankowa St, 40-007, Katowice, Poland
| | - Vitor F O Miranda
- Departamento de Biologia Aplicada à Agropecuária, Universidade Estadual Paulista (Unesp), Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal, São Paulo, Brazil
| | - Bartosz J Płachno
- Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University in Kraków, 9 Gronostajowa St, 30-387, Kraków, Poland.
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Chen KH, Lu JY, Wang CN. Effective pollination of Aeschynanthus acuminatus (Gesneriaceae) by generalist passerines, in sunbird-absent East Asia. Sci Rep 2019; 9:17552. [PMID: 31772181 PMCID: PMC6879542 DOI: 10.1038/s41598-019-53035-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 10/23/2019] [Indexed: 11/30/2022] Open
Abstract
Aeschynanthus (Gesneriaceae), a genus comprising approximately 160 species in subtropical Southeast Asia, has red, tubular flowers, typical of a sunbird pollination syndrome. A. acuminatus, the species that is distributed extending to the northern edge of the genus, where the specialized nectarivorous sunbirds are absent, possesses reddish-green flowers and a wide-open corolla tube, flowering time shifts from summer to winter and the species achieves high fruiting success. This atypical flower led us to investigate the pollination biology of this species. Three species of generalist passerines, Grey-cheeked Fulvetta (Alcippe morrisonia, Sylviidae), White-eared Sibia (Heterophasia auricularis, Leiothrichidae) and Taiwan Yuhina (Yuhina brunneiceps, Zosteropidae), were recorded visiting A. acuminatus flowers. Pollination effectiveness was quantified via conspecific pollen presence on stigmas and natural fruit set. The significantly high natural fruit set (60%) and conspecific pollen transfer rate (94%) indicate high reproductive success facilitated by the accurate pollen placement on the birds. The existence of copious (61 µL) and highly diluted (7%) hexose-dominant nectar, together with a major reflectance peak of corolla lobe in the long-wavelength red color spectrum, is consistent with the pollination syndrome of generalist passerines. The high pollination effectiveness of A. acuminatus due to the recruitment of generalist passerines as pollinators, and the specializations of floral traits to match generalist bird pollination, appear crucial in the successful colonization on islands such as Taiwan that lack specialized bird pollinators.
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Affiliation(s)
- Kai-Hsiu Chen
- Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan
| | - Jing-Yi Lu
- Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan
| | - Chun-Neng Wang
- Department of Life Science, National Taiwan University, Taipei, 10617, Taiwan.
- Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, 10617, Taiwan.
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Pozo MI, Kemenade G, Oystaeyen A, Aledón‐Catalá T, Benavente A, Van den Ende W, Wäckers F, Jacquemyn H. The impact of yeast presence in nectar on bumble bee behavior and fitness. ECOL MONOGR 2019. [DOI: 10.1002/ecm.1393] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- María I. Pozo
- KU Leuven Biology Department Plant Population and Conservation Biology B‐3001 Heverlee Belgium
- Biobest Group, Research and Development B‐2260 Westerlo Belgium
| | - Gaby Kemenade
- KU Leuven Biology Department Plant Population and Conservation Biology B‐3001 Heverlee Belgium
- Biobest Group, Research and Development B‐2260 Westerlo Belgium
| | | | - Tomás Aledón‐Catalá
- KU Leuven Biology Department Plant Population and Conservation Biology B‐3001 Heverlee Belgium
- Biobest Group, Research and Development B‐2260 Westerlo Belgium
| | | | - Wim Van den Ende
- KU Leuven Biology Department Molecular Plant Biology B‐3001 Heverlee Belgium
| | - Felix Wäckers
- Biobest Group, Research and Development B‐2260 Westerlo Belgium
| | - Hans Jacquemyn
- KU Leuven Biology Department Plant Population and Conservation Biology B‐3001 Heverlee Belgium
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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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Ma XL, Milne RI, Zhou HX, Song YQ, Fang JY, Zha HG. Proteomics and post-secretory content adjustment of Nicotiana tabacum nectar. PLANTA 2019; 250:1703-1715. [PMID: 31414205 DOI: 10.1007/s00425-019-03258-4] [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: 06/02/2019] [Accepted: 08/08/2019] [Indexed: 06/10/2023]
Abstract
MAIN CONCLUSION The tobacco nectar proteome mainly consists of pathogenesis-related proteins with two glycoproteins. Expression of nectarins was non-synchronous, and not nectary specific. After secretion, tobacco nectar changed from sucrose rich to hexose rich. Floral nectar proteins (nectarins) play important roles in inhibiting microbial growth in nectar, and probably also tailoring nectar chemistry before or after secretion; however, very few plant species have had their nectar proteomes thoroughly investigated. Nectarins from Nicotiana tabacum (NT) were separated using two-dimensional gel electrophoresis and then analysed using mass spectrometry. Seven nectarins were identified: acidic endochitinase, β-xylosidase, α-galactosidase, α-amylase, G-type lectin S-receptor-like serine/threonine-protein kinase, pathogenesis-related protein 5, and early nodulin-like protein 2. An eighth nectarin, a glycoprotein with unknown function, was identified following isolation from NT nectar using a Qproteome total glycoprotein kit, separation by SDS-PAGE, and identification by mass spectrometry. Expression of all identified nectarins, plus four invertase genes, was analysed by qRT PCR; none of these genes had nectary-specific expression, and none had synchronous expression. The total content of sucrose, hexoses, proteins, phenolics, and hydrogen peroxide were determined at different time intervals in secreted nectar, both within the nectar tube (in vivo) and following extraction from it during incubation at 30 °C for up to 40 h in plastic tubes (in vitro). After secretion, the ratio of hexose to sucrose substantially increased for in vivo nectar, but no sugar composition changes were detected in vitro. This implies that sucrose hydrolysis in vivo might be done by fixed apoplastic invertase. Both protein and hydrogen peroxide levels declined in vitro but not in vivo, implying that some factors other than nectarins act to maintain their levels in the flower, after secretion.
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Affiliation(s)
- Xue-Long Ma
- College of Life and Environment Sciences, Huangshan University, Huangshan, China
| | - Richard I Milne
- Institute of Molecular Plant Sciences, University of Edinburgh, Edinburgh, UK
| | - Hong-Xia Zhou
- College of Life and Environment Sciences, Huangshan University, Huangshan, China
| | - Yue-Qin Song
- College of Life and Environment Sciences, Huangshan University, Huangshan, China
| | - Jiang-Yu Fang
- College of Life and Environment Sciences, Huangshan University, Huangshan, China
| | - Hong-Guang Zha
- College of Life and Environment Sciences, Huangshan University, Huangshan, China.
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Cariveau AB, Anderson E, Baum KA, Hopwood J, Lonsdorf E, Nootenboom C, Tuerk K, Oberhauser K, Snell-Rood E. Rapid Assessment of Roadsides as Potential Habitat for Monarchs and Other Pollinators. Front Ecol Evol 2019. [DOI: 10.3389/fevo.2019.00386] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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Vandelook F, Janssens SB, Gijbels P, Fischer E, Van den Ende W, Honnay O, Abrahamczyk S. Nectar traits differ between pollination syndromes in Balsaminaceae. ANNALS OF BOTANY 2019; 124:269-279. [PMID: 31120478 PMCID: PMC6758581 DOI: 10.1093/aob/mcz072] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 04/30/2019] [Indexed: 05/26/2023]
Abstract
BACKGROUND AND AIMS The attractiveness of nectar rewards depends both on the quantity of nectar produced and on its chemical composition. It is known that nectar quantity and chemical composition can differ in plant species depending on the main pollinator associated with the species. The main aims of this study were to test formally whether nectar traits are adapted to pollination syndromes in the speciose Balsaminaceae and, if so, whether a combination of nectar traits mirrors pollination syndromes. METHODS Comparative methods based on Ornstein-Uhlenbeck models were used to test whether nectar volume, nectar sucrose proportion, sugar and amino acid concentration and amino acid composition had evolved as a function of pollination syndromes in 57 species of Balsaminaceae. Cluster analysis and ordination were performed to derive clusters of species resembling each other in nectar composition. KEY RESULTS Evolutionary models for nectar volume and nectar sucrose proportion performed best when including information on pollination syndrome, while including such information improve model fit neither for sugar and amino acid concentration nor for amino acid composition. A significant relationship emerged between pollination syndrome and the combined nectar traits. CONCLUSIONS Our results show that nectar volume and nectar sucrose proportion evolve rapidly towards optimal values associated with different pollination syndromes. The detection of a signal indicating that nectar traits in combination are to a certain extent able to predict pollination syndromes in Balsaminaceae suggests that a holistic approach including the whole set of nectar traits helps us to better understand evolution of nectar composition in response to pollinators.
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Affiliation(s)
| | - S B Janssens
- Meise Botanic Garden, Meise, Belgium
- Laboratory for Plant Conservation and Population Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - P Gijbels
- Laboratory for Plant Conservation and Population Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - E Fischer
- Institut für Integrierte Naturwissenschaften – Biologie, Universität Koblenz-Landau, Koblenz, Germany
| | - W Van den Ende
- Laboratory for Molecular Plant Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - O Honnay
- Laboratory for Plant Conservation and Population Biology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - S Abrahamczyk
- Nees-Institute for Biodiversity of Plants, University of Bonn, Bonn, Germany
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Dellinger AS, Scheer LM, Artuso S, Fernández-Fernández D, Sornoza F, Penneys DS, Tenhaken R, Dötterl S, Schönenberger J. Bimodal Pollination Systems in Andean Melastomataceae Involving Birds, Bats, and Rodents. Am Nat 2019; 194:104-116. [DOI: 10.1086/703517] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Göttlinger T, Schwerdtfeger M, Tiedge K, Lohaus G. What Do Nectarivorous Bats Like? Nectar Composition in Bromeliaceae With Special Emphasis on Bat-Pollinated Species. FRONTIERS IN PLANT SCIENCE 2019; 10:205. [PMID: 30847001 PMCID: PMC6393375 DOI: 10.3389/fpls.2019.00205] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 02/07/2019] [Indexed: 05/26/2023]
Abstract
Floral nectar is the most important reward for pollinators and an integral component of the pollination syndrome. Nectar research has mainly focused on sugars or amino acids, whereas more comprehensive studies on the nectar composition of closely related plant species with different pollination types are rather limited. Nectar composition as well as concentrations of sugars, amino acids, inorganic ions, and organic acids were analyzed for 147 species of Bromeliaceae. This plant family shows a high diversity in terms of floral morphology, flowering time, and predominant pollination types (trochilophilous, trochilophilous/entomophilous, psychophilous, sphingophilous, chiropterophilous). Based on the analyses, we examined the relationship between nectar traits and pollination type in this family. Nectar of all analyzed species contained high amounts of sugars with different proportions of glucose, fructose, and sucrose. The total concentrations of amino acids, inorganic cations, and anions, or organic acids were much lower. The analyses revealed that the sugar composition, the concentrations of inorganic cations and anions as well as the concentration of malate in nectar of bat-pollinated species differed significantly from nectar of species with other pollination types. Flowers of bat-pollinated species contained a higher volume of nectar, which results in a total of about 25-fold higher amounts of sugar in bat-pollinated species than in insect-pollinated species. This difference was even higher for amino acids, inorganic anions and cations, and organic acids (between 50 and 100-fold). In general, bat-pollinated plant species invest large amounts of organic and inorganic compounds for their pollinators. Furthermore, statistical analyses reveal that the characteristics of nectar in Bromeliaceae are more strongly determined by the pollinator type rather than by taxonomic groups or phylogenetic relations. However, a considerable part of the variance cannot be explained by either of the variables, which means that additional factors must be responsible for the differences in the nectar composition.
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Affiliation(s)
- Thomas Göttlinger
- Molecular Plant Science and Plant Biochemistry, University of Wuppertal, Wuppertal, Germany
| | - Michael Schwerdtfeger
- Albrecht-von-Haller-Institute for Plant Sciences, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Kira Tiedge
- Molecular Plant Science and Plant Biochemistry, University of Wuppertal, Wuppertal, Germany
| | - Gertrud Lohaus
- Molecular Plant Science and Plant Biochemistry, University of Wuppertal, Wuppertal, Germany
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Lozada-Gobilard S, Weigend M, Fischer E, Janssens SB, Ackermann M, Abrahamczyk S. Breeding systems in Balsaminaceae in relation to pollen/ovule ratio, pollination syndromes, life history and climate zone. PLANT BIOLOGY (STUTTGART, GERMANY) 2019; 21:157-166. [PMID: 30134002 DOI: 10.1111/plb.12905] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 08/20/2018] [Indexed: 06/08/2023]
Abstract
Pollen/ovule (P/O) ratios are often used as proxy for breeding systems. Here, we investigate the relations between breeding systems and P/O ratios, pollination syndromes, life history and climate zone in Balsaminaceae. We conducted controlled breeding system experiments (autonomous and active self-pollination and outcrossing tests) for 65 Balsaminaceae species, analysed pollen grain and ovule numbers and evaluated the results in combination with data on pollination syndrome, life history and climate zone on a phylogenetic basis. Based on fruit set, we assigned three breeding systems: autogamy, self-compatibility and self-incompatibility. Self-pollination led to lower fruit set than outcrossing. We neither found significant P/O differences between breeding systems nor between pollination syndromes. However, the numbers of pollen grains and ovules per flower were significantly lower in autogamous species, but pollen grain and ovule numbers did not differ between most pollination syndromes. Finally, we found no relation between breeding system and climate zone, but a relation between climate zone and life history. In Balsaminaceae reproductive traits can change under resource or pollinator limitation, leading to the evolution of autogamy, but are evolutionary rather constant and not under strong selection pressure by pollinator guild and geographic range changes. Colonisation of temperate regions, however, is correlated with transitions towards annual life history. Pollen/ovule-ratios, commonly accepted as good indicators of breeding system, have a low predictive value in Balsaminaceae. In the absence of experimental data on breeding system, additional floral traits (overall pollen grain and ovule number, traits of floral morphology) may be used as proxies.
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Affiliation(s)
- S Lozada-Gobilard
- Nees Institute for Biodiversity of Plants, University of Bonn, Bonn, Germany
- Biodiversity Research/Systematic Botany, Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - M Weigend
- Nees Institute for Biodiversity of Plants, University of Bonn, Bonn, Germany
| | - E Fischer
- Institute for Integrated Natural Sciences - Biology, University of Koblenz-Landau, Koblenz, Germany
| | | | - M Ackermann
- Institute for Integrated Natural Sciences - Biology, University of Koblenz-Landau, Koblenz, Germany
| | - S Abrahamczyk
- Nees Institute for Biodiversity of Plants, University of Bonn, Bonn, Germany
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Płachno BJ, Stpiczyńska M, Świątek P, Lambers H, Miranda VFO, Nge FJ, Stolarczyk P, Cawthray GR. Floral micromorphology of the bird-pollinated carnivorous plant species Utricularia menziesii R.Br. (Lentibulariaceae). ANNALS OF BOTANY 2019; 123:213-220. [PMID: 30169570 PMCID: PMC6344090 DOI: 10.1093/aob/mcy163] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 08/10/2018] [Indexed: 05/11/2023]
Abstract
BACKGROUND AND AIMS Bird pollination is rare among species in the genus Utricularia, and has evolved independently in two lineages of this genus. In Western Australia, the Western Spinebill, Acanthorhynchus superciliosus, visits flowers of Utricularia menziesii (section Pleiochasia: subgenus Polypompholyx). This study aimed to examine the micromorphology of U. menziesii flowers to assess traits that might be linked to its pollination strategy. METHODS Light microscopy, histochemistry and scanning electron microscopy were used. Nectar sugar composition was analysed using high-performance liquid chromatography. KEY RESULTS The flowers of U. menziesii fulfil many criteria that characterize bird-pollinated flowers: red colour, a large, tough nectary spur that can withstand contact with a hard beak, lack of visual nectar guides and fragrance. Trichomes at the palate and throat may act as tactile signals. Spur nectary trichomes did not form clearly visible patches, but were more frequently distributed along vascular bundles, and were small and sessile. Each trichome comprised a single basal cell, a unicellular short pedestal cell (barrier cell) and a multicelled head. These trichomes were much smaller than those of the U. vulgaris allies. Hexose-dominated nectar was detected in flower spurs. Fructose and glucose were present in equal quantities (43 ± 3.6 and 42 ± 3.6 g L-1). Sucrose was only detected in one sample, essentially at the limit of detection for the method used. This type of nectar is common in flowers pollinated by passerine perching birds. CONCLUSIONS The architecture of nectary trichomes in U. menziesii was similar to that of capitate trichomes of insect-pollinated species in this genus; thus, the most important specializations to bird pollination were flower colour (red), and both spur shape and size modification. Bird pollination is probably a recent innovation in the genus Utricularia, subgenus Polypompholyx, and is likely to have evolved from bee-pollinated ancestors.
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Affiliation(s)
- Bartosz J Płachno
- Department of Plant Cytology and Embryology, Jagiellonian University in Kraków, Cracow, Poland
- For correspondence. E-mail
| | - Małgorzata Stpiczyńska
- Botanic Garden, Faculty of Biology, University of Warsaw, Al. Ujazdowskie, Warsaw, Poland
| | - Piotr Świątek
- Department of Animal Histology and Embryology, University of Silesia in Katowice, Katowice, Poland
| | - Hans Lambers
- School of Biological Sciences, University of Western Australia (M084), Crawley (Perth), WA, Australia
| | - Vitor F O Miranda
- Universidade Estadual Paulista (Unesp), Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal, Departamento de Biologia Aplicada à Agropecuária, São Paulo, Brazil
| | - Francis J Nge
- School of Biological Sciences, Faculty of Science, The University of Adelaide, Adelaide, South Australia, Australia
| | - Piotr Stolarczyk
- Unit of Botany and Plant Physiology, Institute of Plant Biology and Biotechnology, University of Agriculture in Kraków, Kraków, Poland
| | - Gregory R Cawthray
- School of Biological Sciences, University of Western Australia (M084), Crawley (Perth), WA, Australia
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Płachno BJ, Stpiczyńska M, Adamec L, Miranda VFO, Świątek P. Nectar trichome structure of aquatic bladderworts from the section Utricularia (Lentibulariaceae) with observation of flower visitors and pollinators. PROTOPLASMA 2018; 255:1053-1064. [PMID: 29404696 PMCID: PMC5994208 DOI: 10.1007/s00709-018-1216-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 01/26/2018] [Indexed: 05/09/2023]
Abstract
In Utricularia, the flower spur is a nectary and in this organ, nectar is produced and stored. This study aimed to examine the structure of the nectary trichomes in four Utricularia species (Utricularia vulgaris L., U. australis R.Br., U. bremii Heer and U. foliosa L.) from the generic section Utricularia. We have investigated whether species with different spur morphology had similar spur anatomy and nectary trichome structure. In Utricularia flowers, nectar is produced by spur capitate trichomes (sessile or stalked). Our results showed that regardless of the various spur morphology, trichomes have similar architecture and ultrastructure. Head cells of these trichomes are transfer cells with an eccrine nectar secretion. Examined species differed in the micromorphology of papillae in spurs. The fly Eristalis tenax was found to be a pollinator of U. vulgaris. Small Halictidae bees seem to be pollinators of U. foliosa.
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Affiliation(s)
- Bartosz J Płachno
- Department of Plant Cytology and Embryology, 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
| | - Lubomír Adamec
- Section of Plant Ecology, Institute of Botany of the Czech Academy of Sciences, Dukelská 135, -37982, Třeboň, CZ, Czech Republic
| | - Vitor Fernandes Oliveira Miranda
- Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal, Departamento de Biologia Aplicada à Agropecuária, Universidade Estadual Paulista (Unesp), São Paulo, Brazil
| | - Piotr Świątek
- Department of Animal Histology and Embryology, University of Silesia in Katowice, 9 Bankowa St, 40-007, Katowice, Poland
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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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