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Rivest S, Lee ST, Cook D, Forrest JRK. Consequences of pollen defense compounds for pollinators and antagonists in a pollen-rewarding plant. Ecology 2024; 105:e4306. [PMID: 38590050 DOI: 10.1002/ecy.4306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 01/09/2024] [Accepted: 02/19/2024] [Indexed: 04/10/2024]
Abstract
Plants produce an array of defensive compounds with toxic or deterrent effects on insect herbivores. Pollen can contain relatively high concentrations of such defense compounds, but the causes and consequences of this enigmatic phenomenon remain mostly unknown. These compounds could potentially protect pollen against antagonists but could also reduce flower attractiveness to pollinators. We combined field observations of the pollen-rewarding Lupinus argenteus with chemical analysis and laboratory assays to test three hypotheses for the presence of pollen defense compounds: (1) these compounds are the result of spillover from adjacent tissues, (2) they protect against pollen thieves, and (3) they act as antimicrobial compounds. We also tested whether pollen defense compounds affect pollinator behavior. We found a positive relationship between alkaloid concentrations in pollen and petals, supporting the idea that pollen defense compounds partly originate from spillover. However, pollen and petals exhibited quantitatively (but not qualitatively) distinct alkaloid profiles, suggesting that plants can adjust pollen alkaloid composition independently from that of adjacent tissues. We found no relationship between pollen alkaloid concentration and the abundance of pollen thieves in Lupinus flowers. However, pollen alkaloids were negatively associated with bacterial abundance. Finally, plants with more alkaloids in their pollen received more pollinator visits, but these visits were shorter, resulting in no change in the overall number of flowers visited. We propose that pollen defense compounds are partly the result of spillover from other tissues, while they also play an antimicrobial role. The absence of negative effects of these compounds on pollinator visitation likely allows their maintenance in pollen at relatively high concentrations. Taken together, our results suggest that pollen alkaloids affect and are mediated by the interplay of multiple interactions.
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Affiliation(s)
- Sébastien Rivest
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
- Rocky Mountain Biological Laboratory, Crested Butte, Colorado, USA
| | - Stephen T Lee
- USDA ARS Poisonous Plant Research Laboratory, Logan, Utah, USA
| | - Daniel Cook
- USDA ARS Poisonous Plant Research Laboratory, Logan, Utah, USA
| | - Jessica R K Forrest
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
- Rocky Mountain Biological Laboratory, Crested Butte, Colorado, USA
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2
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Na SJ, Kim YK, Park JM. Nectar Characteristics and Honey Production Potential of Five Rapeseed Cultivars and Two Wildflower Species in South Korea. PLANTS (BASEL, SWITZERLAND) 2024; 13:419. [PMID: 38337952 PMCID: PMC10856812 DOI: 10.3390/plants13030419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 01/26/2024] [Accepted: 01/29/2024] [Indexed: 02/12/2024]
Abstract
The growing beekeeping industry in South Korea has led to the establishment of new honey plant complexes. However, studies on honey production from each species are limited. This study aimed to assess the honey production potential of various Brassica napus cultivars and two wildflower species. The nectar characteristics of B. napus varied significantly among the cultivars. Absolute sugar concentrations differed among the cultivars, but sugar composition ratios were similar. In contrast, the amino acid content remained relatively uniform regarding percentage values, irrespective of the absolute concentrations. Estimations of honey potential production per hectare (kg/ha) resulted in the following ranking among cultivars: 'JM7003' (107.1) > 'YS' (73.0) > 'JM7001' (63.7) > 'TL' (52.7) > 'TM' (42.4). The nectar volume of Pseudolysimachion rotundum var. subintegrum and Leonurus japonicus increased during the flowering stage. P. rotundum var. subintegrum was sucrose-rich and L. japonicus was sucrose-dominant. Both species predominantly contained phenylalanine, P. rotundum var. subintegrum had glutamine as the second most abundant amino acid, and L. japonicus had tyrosine. The honey production potential was 152.4 kg/ha for P. rotundum var. subintegrum and 151.3 kg/ha for L. japonicus. These findings provide a basis for identifying food resources for pollinators and selecting plant species to establish honey plant complexes.
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Affiliation(s)
- Sung-Joon Na
- Department of Forest Bioresources, National Institute of Forest Science, Suwon 16631, Republic of Korea; (Y.-K.K.); (J.-M.P.)
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3
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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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4
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Barberis M, Calabrese D, Galloni M, Nepi M. Secondary Metabolites in Nectar-Mediated Plant-Pollinator Relationships. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12030550. [PMID: 36771634 PMCID: PMC9920422 DOI: 10.3390/plants12030550] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/17/2023] [Accepted: 01/19/2023] [Indexed: 06/01/2023]
Abstract
In recent years, our understanding of the complex chemistry of floral nectar and its ecological implications for plant-pollinator relationships has certainly increased. Nectar is no longer considered merely a reward for pollinators but rather a plant interface for complex interactions with insects and other organisms. A particular class of compounds, i.e., nectar secondary compounds (NSCs), has contributed to this new perspective, framing nectar in a more comprehensive ecological context. The aim of this review is to draft an overview of our current knowledge of NSCs, including emerging aspects such as non-protein amino acids and biogenic amines, whose presence in nectar was highlighted quite recently. After considering the implications of the different classes of NSCs in the pollination scenario, we discuss hypotheses regarding the evolution of such complex nectar profiles and provide cues for future research on plant-pollinator relationships.
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Affiliation(s)
- Marta Barberis
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Via Irnerio 42, 40126 Bologna, Italy
| | - Daniele Calabrese
- Department of Life Sciences, University of Siena, Via P.A. Mattioli 4, 53100 Siena, Italy
| | - Marta Galloni
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Via Irnerio 42, 40126 Bologna, Italy
| | - Massimo Nepi
- Department of Life Sciences, University of Siena, Via P.A. Mattioli 4, 53100 Siena, Italy
- National Biodiversity Future Centre (NBFC), 90123 Palermo, Italy
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5
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Herbivory, plant traits and nectar chemistry interact to affect the community of insect visitors and pollination in common milkweed, Asclepias syriaca. Oecologia 2023; 201:91-105. [PMID: 36456875 DOI: 10.1007/s00442-022-05290-w] [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: 05/24/2022] [Accepted: 11/07/2022] [Indexed: 12/04/2022]
Abstract
Herbivory can alter plant fitness directly through changing reproductive allocation and indirectly through changing pollinator identity or behavior. Common milkweed is a plant of conservation concern with an inducible chemical defense that is also an important nectar resource. In this study, we aim to understand how herbivory severity and plant traits, including morphology and nectar chemistry, interact to affect insect visitation and pod production in common milkweed. We conducted pollinator watches on plants with experimentally varied herbivory severity and quantified insect frequency and visit length as a response to nectar chemistry, ramet height, number of inflorescences, number of flowers per inflorescence and percent tissue removed. We also quantified pollinator effectiveness and importance. Increased herbivory severity reduced floral displays, including fewer inflorescences and fewer flowers per inflorescence. A reduced floral display was correlated with reduced sucrose, fructose and glucose and resulted in a reduced number and species richness of insect visitors. Fewer flowers per inflorescence reduced the frequency of bumble bee and fly visitors, which were two important pollinators. Although honeybees, flies, small bees, soldier beetles and bumble bees were equally effective pollinators, only bumble bee frequency was positively correlated with pod production. The differences in pollinator visitation have the potential to create diversifying selection on plant floral traits, many of which are also affected by herbivores. This research demonstrates potentially conflicting selection pressures between native and non-native pollinators as well as non-native herbivores.
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6
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Göttlinger T, Lohaus G. Comparative analyses of the metabolite and ion concentrations in nectar, nectaries, and leaves of 36 bromeliads with different photosynthesis and pollinator types. FRONTIERS IN PLANT SCIENCE 2022; 13:987145. [PMID: 36092434 PMCID: PMC9459329 DOI: 10.3389/fpls.2022.987145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 08/08/2022] [Indexed: 06/15/2023]
Abstract
Floral nectar contains mainly sugars as well as smaller amounts of amino acids and further compounds. The nectar composition varies between different plant species and it is related to the pollination type of the plant. In addition to this, other factors can influence the composition. Nectar is produced in and secreted from nectaries. A few models exist to explain the origin of nectar for dicotyl plant species, a complete elucidation of the processes, however, has not yet been achieved. This is particularly true for monocots or plant species with CAM photosynthesis. To get closer to such an elucidation, nectar, nectaries, and leaves of 36 bromeliad species were analyzed for sugars, starch, amino acids, and inorganic ions. The species studied include different photosynthesis types (CAM/C3), different pollination types (trochilophilous/chiropterophilous), or different live forms. The main sugars in nectar and nectaries were glucose, fructose, and sucrose, the total sugar concentration was about twofold higher in nectar than in nectaries, which suggests that sugars are actively transported from the nectaries into the nectar. The composition of amino acids in nectar is already determined in the nectaries, but the concentration is much lower in nectar than in nectaries, which suggests selective retention of amino acids during nectar secretion. The same applies to inorganic ions. Statistical analyses showed that the photosynthesis type and the pollination type can explain more data variation in nectar than in nectaries and leaves. Furthermore, the pollinator type has a stronger influence on the nectar or nectary composition than the photosynthesis type. Trochilophilous C3 plants showed significant correlations between the nitrate concentration in leaves and the amino acid concentration in nectaries and nectar. It can be assumed that the more nitrate is taken up, the more amino acids are synthesized in leaves and transported to the nectaries and nectar. However, chiropterophilous C3 plants show no such correlation, which means that the secretion of amino acids into the nectar is regulated by further factors. The results help understand the physiological properties that influence nectaries and nectar as well as the manner of metabolite and ion secretion from nectaries to nectar.
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7
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Palmer-Young EC, Schwarz RS, Chen Y, Evans JD. Punch in the gut: Parasite tolerance of phytochemicals reflects host diet. Environ Microbiol 2022; 24:1805-1817. [PMID: 35315572 DOI: 10.1111/1462-2920.15981] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 03/18/2022] [Accepted: 03/20/2022] [Indexed: 11/30/2022]
Abstract
Gut parasites of plant-eating insects are exposed to antimicrobial phytochemicals that can reduce infection. Trypanosomatid gut parasites infect insects of diverse nutritional ecologies as well as mammals and plants, raising the question of how host diet-associated phytochemicals shape parasite evolution and host specificity. To test the hypothesis that phytochemical tolerance of trypanosomatids reflects the chemical ecology of their hosts, we compared related parasites from honey bees and mosquitoes-hosts that differ in phytochemical consumption-and contrasted our results with previous studies on phylogenetically related, human-parasitic Leishmania. We identified one bacterial and ten plant-derived substances with known antileishmanial activity that also inhibited honey bee parasites associated with colony collapse. Bee parasites exhibited greater tolerance of chrysin-a flavonoid found in nectar, pollen, and plant resin-derived propolis. In contrast, mosquito parasites were more tolerant of cinnamic acid-a product of lignin decomposition present in woody debris-rich larval habitats. Parasites from both hosts tolerated many compounds that inhibit Leishmania, hinting at possible trade-offs between phytochemical tolerance and mammalian infection. Our results implicate the phytochemistry of host diets as a potential driver of insect-trypanosomatid associations, and identify compounds that could be incorporated into colony diets or floral landscapes to ameliorate infection in bees. This article is protected by copyright. All rights reserved.
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Affiliation(s)
| | - Ryan S Schwarz
- Department of Biology, Fort Lewis College, Durango, CO, USA
| | | | - Jay D Evans
- USDA-ARS Bee Research Lab, Beltsville, MD, USA
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8
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Du JX, Li Y, Ur-Rehman S, Mukhtar I, Yin Z, Dong H, Wang H, Zhang X, Gao Z, Zhao X, Xin X, Ding X. Synergistically promoting plant health by harnessing synthetic microbial communities and prebiotics. iScience 2021; 24:102918. [PMID: 34430808 PMCID: PMC8365361 DOI: 10.1016/j.isci.2021.102918] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Soil-borne diseases cause serious economic losses in agriculture. Managing diseases with microbial preparations is an excellent approach to soil-borne disease prevention. However, microbial preparations often exhibit unstable effects, limiting their large-scale application. This review introduces and summarizes disease-suppressive soils, the relationship between carbon sources and the microbial community, and the application of human microbial preparation concepts to plant microbial preparations. We also propose an innovative synthetic microbial community assembly strategy with synergistic prebiotics to promote healthy plant growth and resistance to disease. In this review, a new approach is proposed to improve traditional microbial preparations; provide a better understanding of the relationships among carbon sources, beneficial microorganisms, and plants; and lay a theoretical foundation for developing new microbial preparations.
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Affiliation(s)
- Jianfeng X. Du
- State Key Laboratory of Crop Biology, Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Taian, Shandong 271018, P. R. China
| | - Yang Li
- State Key Laboratory of Crop Biology, Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Taian, Shandong 271018, P. R. China
| | - Saif- Ur-Rehman
- State Key Laboratory of Crop Biology, Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Taian, Shandong 271018, P. R. China
| | - Irum Mukhtar
- Institute of Oceanography, Minjiang University, Fuzhou 350108, China
| | - Ziyi Yin
- State Key Laboratory of Crop Biology, Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Taian, Shandong 271018, P. R. China
| | - Hansong Dong
- State Key Laboratory of Crop Biology, Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Taian, Shandong 271018, P. R. China
| | - Hongfeng Wang
- Shandong Pengbo Biotechnology Co., LTD, Taian 271018, China
| | - Xiaoying Zhang
- Shandong Pengbo Biotechnology Co., LTD, Taian 271018, China
| | - Zheng Gao
- College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong 271018, P.R. China
| | - Xiangyu Zhao
- College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong 271018, P.R. China
| | - Xiufang Xin
- Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Science and Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences (CAS) and CAS John Innes Centre of Excellence for Plant and Microbial Sciences, Shanghai, China
| | - Xinhua Ding
- State Key Laboratory of Crop Biology, Shandong Provincial Key Laboratory for Biology of Vegetable Diseases and Insect Pests, College of Plant Protection, Shandong Agricultural University, Taian, Shandong 271018, P. R. China
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9
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Bing J, Li X, Haverkamp A, Baldwin IT, Hansson BS, Knaden M, Yon F. Variation in Manduca sexta Pollination-Related Floral Traits and Reproduction in a Wild Tobacco Plant. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.680463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Most flowering plants depend on animal pollination for successful sexual reproduction. Floral signals such as color, shape, and odor are crucial in establishing this (often mutualistic) interaction. Plant and pollinator phenotypes can vary temporally but also spatially, thus creating mosaic-like patterns of local adaptations. Here, we investigated natural variation in floral morphology, flower volatile emission, and phenology in four accessions of a self-compatible wild tobacco, Nicotiana attenuata, to assess how these traits match the sensory perception of a known pollinator, the hawkmoth Manduca sexta. These accessions differ in floral traits and also in their habitat altitudes. Based on habitat temperatures, the accession occurring at the highest altitude (California) is less likely to be visited by M. sexta, while the others (Arizona, Utah 1, and Utah 2) are known to receive M. sexta pollinations. The accessions varied significantly in flower morphologies, volatile emissions, flower opening, and phenology, traits likely important for M. sexta perception and floral handling. In wind tunnel assays, we assessed the seed set of emasculated flowers after M. sexta visitation and of natural selfed and hand-pollinated selfed flowers. After moth visitations, plants of two accessions (Arizona and Utah 2) produced more capsules than the other two, consistent with predictions that accessions co-occurring with M. sexta would benefit more from the pollination services of this moth. We quantified flower and capsule production in four accessions in a glasshouse assay without pollinators to assess the potential for self-pollination. The two Utah accessions set significantly more seeds after pollen supplementation compared with those of autonomous selfing flowers, suggesting a greater opportunistic benefit from efficient pollinators than the other two. Moreover, emasculated flowers of the accession with the most exposed stigma (Utah 2) produced the greatest seed set after M. sexta visitation. This study reveals intraspecific variation in pollination syndromes that illuminate the potential of a plant species to adapt to local pollinator communities, changing environments, and altered pollination networks.
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10
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Frachon L, Stirling SA, Schiestl FP, Dudareva N. Combining biotechnology and evolution for understanding the mechanisms of pollinator attraction. Curr Opin Biotechnol 2021; 70:213-219. [PMID: 34217123 DOI: 10.1016/j.copbio.2021.06.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 06/04/2021] [Accepted: 06/07/2021] [Indexed: 11/15/2022]
Abstract
Many flowering plants rely on pollinators for their reproductive success. Plant-pollinator interactions usually depend on a complex combination of traits based on a fine-tuned biosynthetic machinery, with many structural and regulatory genes involved. Yet, the physiological mechanisms in plants are the product of evolutionary processes. While evolution has been modifying flowers through millions of years, it is also a rapid process that can change plant traits within few generations. Here we discuss both mechanistic and evolutionary aspects of pollinator attraction. We also propose how latest advances in biotechnology and evolutionary studies, and their combination, will improve the elucidation of molecular mechanisms and evolutionary dynamics of pollinator attraction in changing environments.
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Affiliation(s)
- Léa Frachon
- Department of Systematic and Evolutionary Botany, University of Zurich, Zollikerstrasse 107, 8008, Zurich, Switzerland
| | - Shannon A Stirling
- Department of Biochemistry, Purdue University, 175 South University St., West Lafayette, IN 47907-2063, USA
| | - Florian P Schiestl
- Department of Systematic and Evolutionary Botany, University of Zurich, Zollikerstrasse 107, 8008, Zurich, Switzerland.
| | - Natalia Dudareva
- Department of Biochemistry, Purdue University, 175 South University St., West Lafayette, IN 47907-2063, USA; Purdue Center for Plant Biology, Purdue University, West Lafayette, IN 47907, USA.
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11
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Broadhead GT, Raguso RA. Associative learning of non-sugar nectar components: amino acids modify nectar preference in a hawkmoth. J Exp Biol 2021; 224:269206. [PMID: 34142140 PMCID: PMC8246342 DOI: 10.1242/jeb.234633] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 05/20/2021] [Indexed: 11/20/2022]
Abstract
The nearly ubiquitous presence of amino acids in the nectar of flowering plants has led to significant interest in the relevance of these compounds to pollinator behavior and physiology. A number of flower-visiting animals exhibit behavioral preferences for nectar solutions containing amino acids, but these preferences vary by species and are often context or condition dependent. Furthermore, the relative strength of these preferences and potential influence on the foraging behavior of flower-visiting animals remains unclear. Here, we used innate preference tests and associative learning paradigms to examine the nectar preferences of the flower-visiting hawkmoth Manduca sexta, in relation to both sugar and amino acid content. Manduca sexta exhibited a strong preference for higher sucrose concentrations, while the effect of amino acids on innate feeding preference was only marginally significant. However, with experience, moths were able to learn nectar composition and flower color associations and to forage preferentially (against innate color preference) for nectar with a realistic amino acid composition. Foraging moths responding to learned color cues of nectar amino acid content exhibited a behavioral preference comparable to that observed in response to a 5% difference in nectar sucrose concentration. These results demonstrate that experienced foragers may assess nectar amino acid content in addition to nectar sugar content and caloric value during nectar-foraging bouts.
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Affiliation(s)
- Geoffrey T Broadhead
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY14853, USA
| | - Robert A Raguso
- Department of Neurobiology and Behavior, Cornell University, Ithaca, NY14853, USA
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12
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Gunasekaran M, Trabelcy B, Izhaki I, Halpern M. Direct Evidence That Sunbirds' Gut Microbiota Degrades Floral Nectar's Toxic Alkaloids. Front Microbiol 2021; 12:639808. [PMID: 33815326 PMCID: PMC8018289 DOI: 10.3389/fmicb.2021.639808] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 02/08/2021] [Indexed: 12/01/2022] Open
Abstract
Orange-tufted sunbirds (Cinnyris osea) feed on the nectar of the tobacco tree (Nicotiana glauca) which contains toxic pyridine alkaloids characterized by high concentrations of anabasine and much lower concentrations of nicotine. We aimed at determining whether the gut microbiota of sunbirds harbors bacterial species that enable the birds to cope with these toxic alkaloids. An in vivo experiment that included 12 birds showed that inducing dysbiosis in sunbirds’ guts by the addition of sulfamethoxazole and trimethoprim, significantly reduced the birds’ ability to degrade anabasine (n = 3) compared to control birds (n = 3) with undisturbed microbiota. Sunbirds whose gut bacterial communities were altered by the antibacterial agents and who were fed with added nicotine, also showed a lower percentage of nicotine degradation (n = 3) in their excreta compared to the sunbirds with undisturbed microbiota (n = 3), though this difference was not significant. In an in vitro experiment, we studied the ability of Lactococcus lactis, Enterobacter hormaechei, Chryseobacterium gleum, Kocuria palustris, and Methylorubrum populi that were isolated from sunbirds’ excreta, to degrade anabasine and nicotine. By using gas chromatography-mass spectrometry (GC-MS) analysis, we successfully demonstrated, for the first time, the ability of these species to degrade the focal secondary metabolites. Our findings demonstrate the role of gut bacteria in detoxifying toxic secondary metabolites found in the N. glauca nectar. The degradation products may supply the birds with nitrogen which is scarce in nectar-rich diets. These findings support another role of bacteria in mediating the interactions between plants and their pollinators.
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Affiliation(s)
- Mohanraj Gunasekaran
- Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Beny Trabelcy
- Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Ido Izhaki
- Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Malka Halpern
- Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel.,Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Tivon, Israel
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13
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Schmitt A, Roy R, Carter CJ. Nectar antimicrobial compounds and their potential effects on pollinators. CURRENT OPINION IN INSECT SCIENCE 2021; 44:55-63. [PMID: 33771735 DOI: 10.1016/j.cois.2021.03.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 02/24/2021] [Accepted: 03/15/2021] [Indexed: 06/12/2023]
Abstract
Nectar is a sugary, aqueous solution that plants offer as a reward to animal mutualists for visitation. Since nectars are so nutrient-rich, they often harbor significant microbial communities, which can be pathogenic, benign, or even sometimes beneficial to plant fitness. Through recent advances, it is now clear that these microbes alter nectar chemistry, which in turn influences mutualist behavior (e.g. pollinator visitation). To counteract unwanted microbial growth, nectars often contain antimicrobial compounds, especially in the form of proteins, specialized (secondary) metabolites, and metals. This review covers our current understanding of nectar antimicrobials, as well as their interplay with both microbes and insect visitors.
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Affiliation(s)
- Anthony Schmitt
- Department of Plant & Microbial Biology, University of Minnesota, 1479 Gortner Ave, St. Paul, MN 55108, USA
| | - Rahul Roy
- Biology Department, St. Catherine University, 2004 Randolph Ave, St. Paul, MN 55105, USA
| | - Clay J Carter
- Department of Plant & Microbial Biology, University of Minnesota, 1479 Gortner Ave, St. Paul, MN 55108, USA.
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14
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Chiocchio I, Mandrone M, Tomasi P, Marincich L, Poli F. Plant Secondary Metabolites: An Opportunity for Circular Economy. Molecules 2021; 26:495. [PMID: 33477709 PMCID: PMC7831927 DOI: 10.3390/molecules26020495] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/12/2021] [Accepted: 01/15/2021] [Indexed: 12/20/2022] Open
Abstract
Moving toward a more sustainable development, a pivotal role is played by circular economy and a smarter waste management. Industrial wastes from plants offer a wide spectrum of possibilities for their valorization, still being enriched in high added-value molecules, such as secondary metabolites (SMs). The current review provides an overview of the most common SM classes (chemical structures, classification, biological activities) present in different plant waste/by-products and their potential use in various fields. A bibliographic survey was carried out, taking into account 99 research articles (from 2006 to 2020), summarizing all the information about waste type, its plant source, industrial sector of provenience, contained SMs, reported bioactivities, and proposals for its valorization. This survey highlighted that a great deal of the current publications are focused on the exploitation of plant wastes in human healthcare and food (including cosmetic, pharmaceutical, nutraceutical and food additives). However, as summarized in this review, plant SMs also possess an enormous potential for further uses. Accordingly, an increasing number of investigations on neglected plant matrices and their use in areas such as veterinary science or agriculture are expected, considering also the need to implement "greener" practices in the latter sector.
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Affiliation(s)
| | - Manuela Mandrone
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum—University of Bologna, Via Irnerio 42, 40126 Bologna, Italy; (I.C.); (P.T.); (L.M.); (F.P.)
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15
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Davis JK, Aguirre LA, Barber NA, Stevenson PC, Adler LS. From plant fungi to bee parasites: mycorrhizae and soil nutrients shape floral chemistry and bee pathogens. Ecology 2019; 100:e02801. [PMID: 31234229 PMCID: PMC6773465 DOI: 10.1002/ecy.2801] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 04/16/2019] [Accepted: 05/28/2019] [Indexed: 12/19/2022]
Abstract
Bee populations have experienced declines in recent years, due in part to increased disease incidence. Multiple factors influence bee-pathogen interactions, including nectar and pollen quality and secondary metabolites. However, we lack an understanding of how plant interactions with their environment shape bee diet quality. We examined how plant interactions with the belowground environment alter floral rewards and, in turn, bee-pathogen interactions. Soil-dwelling mycorrhizal fungi are considered plant mutualists, although the outcome of the relationship depends on environmental conditions such as nutrients. In a 2 × 2 factorial design, we asked whether mycorrhizal fungi and nutrients affect concentrations of nectar and pollen alkaloids (anabasine and nicotine) previously shown to reduce infection by the gut pathogen Crithidia in the native bumble bee Bombus impatiens. To ask how plant interactions affect this common bee pathogen, we fed pollen and nectar from our treatment plants, and from a wildflower pollen control with artificial nectar, to bees infected with Crithidia. Mycorrhizal fungi and fertilizer both influenced flowering phenology and floral chemistry. While we found no anabasine or nicotine in nectar, high fertilizer increased anabasine and nicotine in pollen. Arbuscular mycorrhizal fungi (AMF) decreased nicotine concentrations, but the reduction due to AMF was stronger in high than low-nutrient conditions. AMF and nutrients also had interactive effects on bee pathogens via changes in nectar and pollen. High fertilizer reduced Crithidia cell counts relative to low fertilizer in AMF plants, but increased Crithidia in non-AMF plants. These results did not correspond with effects of fertilizer and AMF on pollen alkaloid concentrations, suggesting that other components of pollen or nectar were affected by treatments and shaped pathogen counts. Our results indicate that soil biotic and abiotic environment can alter bee-pathogen interactions via changes in floral rewards, and underscore the importance of integrative studies to predict disease dynamics and ecological outcomes.
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Affiliation(s)
- Julie K. Davis
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, USA
- Department of Entomology, Cornell University, Ithaca, NY 14850, USA
| | - Luis A. Aguirre
- Department of Biology, University of Massachusetts, Amherst, MA 01003, USA
| | - Nicholas A. Barber
- Department of Biological Sciences, San Diego State University, San Diego, CA 92182, USA
| | - Philip C. Stevenson
- Jodrell Laboratory, Royal Botanic Gardens, Kew, Surrey TW9 3AB, UK
- Natural Resources Institute, University of Greenwich, Chatham, Kent ME4 4TB, UK
| | - Lynn S. Adler
- Department of Biology, University of Massachusetts, Amherst, MA 01003, USA
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16
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Wang Y, Jiao H, Jiang P, Zhao H. Functional divergence of bitter taste receptors in a nectar-feeding bird. Biol Lett 2019; 15:20190461. [PMID: 31551065 DOI: 10.1098/rsbl.2019.0461] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Nectar may contain many secondary metabolites that are commonly toxic and bitter-tasting. It has been hypothesized that such bitter-tasting secondary metabolites might keep the nectar exclusive to only a few pollinators. To test this hypothesis, we examined functional changes of bitter taste receptor genes (Tas2rs) in a species of nectar-feeding bird (Anna's hummingbird) by comparing these genes with those from two closely related insect-feeding species (chimney swift and chuck-will's widow). We previously identified a larger number of Tas2rs in the hummingbird than in its close insectivorous relatives. In the present study, we demonstrate higher sensitivity and new functions in the hummingbird Tas2r gene copies generated by a lineage-specific duplication, which has been shaped by positive selection. These results suggest that the bitter taste may lead to increased sensitivities and specialized abilities of the hummingbird to detect bitter-tasting nectar. Moreover, this study potentially supports the hypothesis that bitter-tasting nectar may have been specialized for some pollinators, thus enforcing plant-pollinator mutualism.
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Affiliation(s)
- Yi Wang
- Department of Ecology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, People's Republic of China.,Monell Chemical Senses Center, Philadelphia, PA 19104, USA
| | - Hengwu Jiao
- Department of Ecology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Peihua Jiang
- Monell Chemical Senses Center, Philadelphia, PA 19104, USA
| | - Huabin Zhao
- Department of Ecology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, People's Republic of China
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17
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Ray R, Li D, Halitschke R, Baldwin IT. Using natural variation to achieve a whole-plant functional understanding of the responses mediated by jasmonate signaling. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2019; 99:414-425. [PMID: 30927293 DOI: 10.1111/tpj.14331] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 02/25/2019] [Accepted: 02/27/2019] [Indexed: 06/09/2023]
Abstract
The dramatic advances in our understanding of the molecular biology and biochemistry of jasmonate (JA) signaling have been the subject of several excellent recent reviews that have highlighted the phytohormonal function of this signaling pathway. Here, we focus on the responses mediated by JA signaling which have consequences for a plant's Darwinian fitness, i.e. the organism-level function of JA signaling. The most diverse module in the signaling cascade, the JAZ proteins, and their interactions with other proteins and transcription factors, allow this canonical signaling cascade to mediate a bewildering array of traits in different tissues at different times; the functional coherence of these diverse responses are best appreciated in an organismal/ecological context. From published work, it appears that jasmonates can function as the 'Swiss Army knife' of plant signaling, mediating many different biotic and abiotic stress and developmental responses that allow plants to contextualize their responses to their frequently changing local environments and optimize their fitness. We propose that a deeper analysis of the natural variation in both within-plant and within-population JA signaling components is a profitable means of attaining a coherent whole-plant functional perspective of this signaling cascade, and provide examples of this approach from the Nicotiana attenuata system.
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Affiliation(s)
- Rishav Ray
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745, Jena, Germany
| | - Dapeng Li
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745, Jena, Germany
| | - Rayko Halitschke
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745, Jena, Germany
| | - Ian T Baldwin
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745, Jena, Germany
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18
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Parachnowitsch AL, Manson JS, Sletvold N. Evolutionary ecology of nectar. ANNALS OF BOTANY 2019; 123:247-261. [PMID: 30032269 PMCID: PMC6344224 DOI: 10.1093/aob/mcy132] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Accepted: 06/16/2018] [Indexed: 05/24/2023]
Abstract
Background Floral nectar is an important determinant of plant-pollinator interactions and an integral component of pollination syndromes, suggesting it is under pollinator-mediated selection. However, compared to floral display traits, we know little about the evolutionary ecology of nectar. Combining a literature review with a meta-analysis approach, we summarize the evidence for heritable variation in nectar traits and link this variation to pollinator response and plant fitness. We further review associations between nectar traits and floral signals and discuss them in the context of honest signalling and targets of selection. Scope Although nectar is strongly influenced by environmental factors, heritable variation in nectar production rate has been documented in several populations (mean h2 = 0.31). Almost nothing is known about heritability of other nectar traits, such as sugar and amino acid concentrations. Only a handful of studies have quantified selection on nectar traits, and few find statistically significant selection. Pollinator responses to nectar traits indicate they may drive selection, but studies tying pollinator preferences to plant fitness are lacking. So far, only one study conclusively identified pollinators as selective agents on a nectar trait, and the role of microbes, herbivores, nectar robbers and abiotic factors in nectar evolution is largely hypothetical. Finally, there is a trend for positive correlations among floral cues and nectar traits, indicating honest signalling of rewards. Conclusions Important progress can be made by studies that quantify current selection on nectar in natural populations, as well as experimental approaches that identify the target traits and selective agents involved. Signal-reward associations suggest that correlational selection may shape evolution of nectar traits, and studies exploring these more complex forms of natural selection are needed. Many questions about nectar evolution remain unanswered, making this a field ripe for future research.
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Affiliation(s)
- Amy L Parachnowitsch
- Plant Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
- Department of Biology, University of New Brunswick, Fredericton, New Brunswick, Canada
| | - Jessamyn S Manson
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Nina Sletvold
- Plant Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
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19
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Palmer-Young EC, Farrell IW, Adler LS, Milano NJ, Egan PA, Junker RR, Irwin RE, Stevenson PC. Chemistry of floral rewards: intra- and interspecific variability of nectar and pollen secondary metabolites across taxa. ECOL MONOGR 2018. [DOI: 10.1002/ecm.1335] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Evan C. Palmer-Young
- Department of Biology; University of Massachusetts at Amherst; Amherst Massachusetts 01003 USA
| | - Iain W. Farrell
- Royal Botanic Gardens, Kew; Richmond Surrey TW9 3AB United Kingdom
| | - Lynn S. Adler
- Department of Biology; University of Massachusetts at Amherst; Amherst Massachusetts 01003 USA
| | - Nelson J. Milano
- Department of Biology; University of Massachusetts at Amherst; Amherst Massachusetts 01003 USA
| | - Paul A. Egan
- Department of Plant Protection Biology; Swedish University of Agricultural Sciences; SE-23053 Alnarp Sweden
| | - Robert R. Junker
- Department of Bioscience; University of Salzburg; Hellbrunnerstrasse 34 5020 Salzburg Austria
| | - Rebecca E. Irwin
- Department of Applied Ecology; North Carolina State University; Raleigh North Carolina 27695 USA
| | - Philip C. Stevenson
- Royal Botanic Gardens, Kew; Richmond Surrey TW9 3AB United Kingdom
- University of Greenwich; Medway ME4 4 TB United Kingdom
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20
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Schuman MC, Baldwin IT. Field studies reveal functions of chemical mediators in plant interactions. Chem Soc Rev 2018; 47:5338-5353. [PMID: 29770376 DOI: 10.1039/c7cs00749c] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Plants are at the trophic base of most ecosystems, embedded in a rich network of ecological interactions in which they evolved. While their limited range and speed of motion precludes animal-typical behavior, plants are accomplished chemists, producing thousands of specialized metabolites which may function to convey information, or even to manipulate the physiology of other organisms. Plants' complex interactions and their underlying mechanisms are typically dissected within the controlled environments of growth chambers and glasshouses, but doing so introduces conditions alien to plants evolved in natural environments, such as being pot-bound, and receiving artificial light with a spectrum very different from sunlight. The mechanistic understanding gained from a reductionist approach provides the tools required to query and manipulate plant interactions in real-world settings. The few tests conducted in natural ecosystems and agricultural fields have highlighted the limitations of studying plant interactions only in artificial environments. Here, we focus on three examples of known or hypothesized chemical mediators of plants' interactions: the volatile phytohormone ethylene (ET), more complex plant volatile blends, and as-yet-unknown mediators transferred by common mycorrhizal networks (CMNs). We highlight how mechanistic knowledge has advanced research in all three areas, and the critical importance of field work if we are to put our understanding of chemical ecology on rigorous experimental and theoretical footing, and demonstrate function.
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Affiliation(s)
- Meredith C Schuman
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany.
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21
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Nepi M, Grasso DA, Mancuso S. Nectar in Plant-Insect Mutualistic Relationships: From Food Reward to Partner Manipulation. FRONTIERS IN PLANT SCIENCE 2018; 9:1063. [PMID: 30073014 PMCID: PMC6060274 DOI: 10.3389/fpls.2018.01063] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 06/29/2018] [Indexed: 05/27/2023]
Abstract
It has been known for centuries that floral and extra-floral nectar secreted by plants attracts and rewards animals. Extra-floral nectar is involved in so-called indirect defense by attracting animals (generally ants) that prey on herbivores, or by discouraging herbivores from feeding on the plant. Floral nectar is presented inside the flower close to the reproductive organs and rewards animals that perform pollination while visiting the flower. In both cases nectar is a source of carbon and nitrogen compounds that feed animals, the most abundant solutes being sugars and amino acids. Plant-animal relationships involving the two types of nectar have therefore been used for a long time as text-book examples of symmetric mutualism: services provided by animals to plants in exchange for food provided by plants to animals. Cheating (or deception or exploitation), namely obtaining the reward/service without returning any counterpart, is however, well-known in mutualistic relationships, since the interacting partners have conflicting interests and selection may favor cheating strategies. A more subtle way of exploiting mutualism was recently highlighted. It implies the evolution of strategies to maximize the benefits obtained by one partner while still providing the reward/service to the other partner. Several substances other than sugars and amino acids have been found in nectar and some affect the foraging behavior of insects and potentially increase the benefits to the plant. Such substances can be considered plant cues to exploit mutualism. Recent evidence motivated some authors to use the term "manipulation" of animals by plants in nectar-mediated mutualistic relationships. This review highlights the recent background of the "manipulation" hypothesis, discussing it in the framework of new ecological and evolutionary scenarios in plant-animal interactions, as a stimulus for future research.
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Affiliation(s)
- Massimo Nepi
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Donato A. Grasso
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, Italy
| | - Stefano Mancuso
- Department of Agrifood Production and Environmental Sciences, University of Florence, Florence, Italy
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22
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Velázquez-López R, Wegier A, Alavez V, Pérez-López J, Vázquez-Barrios V, Arroyo-Lambaer D, Ponce-Mendoza A, Kunin WE. The Mating System of the Wild-to-Domesticated Complex of Gossypium hirsutum L. Is Mixed. FRONTIERS IN PLANT SCIENCE 2018; 9:574. [PMID: 29868048 PMCID: PMC5954804 DOI: 10.3389/fpls.2018.00574] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 04/13/2018] [Indexed: 05/18/2023]
Abstract
The domestication syndrome of many plants includes changes in their mating systems. The evolution of the latter is shaped by ecological and genetic factors that are particular to an area. Thus, the reproductive biology of wild relatives must be studied in their natural distribution to understand the mating system of a crop species as a whole. Gossypium hirsutum (upland cotton) includes both domesticated varieties and wild populations of the same species. Most studies on mating systems describe cultivated cotton as self-pollinated, while studies on pollen dispersal report outcrossing; however, the mating system of upland cotton has not been described as mixed and little is known about its wild relatives. In this study we selected two wild metapopulations for comparison with domesticated plants and one metapopulation with evidence of recent gene flow between wild relatives and the crop to evaluate the mating system of cotton's wild-to-domesticated complex. Using classic reproductive biology methods, our data demonstrate that upland cotton presents a mixed mating system throughout the complex. Given cotton's capacity for outcrossing, differences caused by the domestication process in cultivated individuals can have consequences for its wild relatives. This characterization of the diversity of the wild relatives in their natural distribution, as well as their interactions with the crop, will be useful to design and implement adequate strategies for conservation and biosecurity.
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Affiliation(s)
- Rebeca Velázquez-López
- Laboratorio de Genética de la Conservación, Jardín Botánico, Instituto de Biología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Ana Wegier
- Laboratorio de Genética de la Conservación, Jardín Botánico, Instituto de Biología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Valeria Alavez
- Laboratorio de Genética de la Conservación, Jardín Botánico, Instituto de Biología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Javier Pérez-López
- Laboratorio de Genética de la Conservación, Jardín Botánico, Instituto de Biología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Valeria Vázquez-Barrios
- Laboratorio de Genética de la Conservación, Jardín Botánico, Instituto de Biología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Denise Arroyo-Lambaer
- Laboratorio de Genética de la Conservación, Jardín Botánico, Instituto de Biología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | | | - William E. Kunin
- Department of Ecology and Evolution, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom
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Misaki A, Itagaki T, Matsubara Y, Sakai S. Intraflower variation in nectar secretion: Secretion patterns and pollinator behavior in male- and female-phase flowers. AMERICAN JOURNAL OF BOTANY 2018; 105:842-850. [PMID: 29893413 DOI: 10.1002/ajb2.1099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 02/21/2018] [Indexed: 06/08/2023]
Abstract
PREMISE OF THE STUDY Plants that secrete abundant nectar attract many pollinator visits, potentially leading to a high frequency of geitonogamous pollination. However, intraflower variation in nectar volume might enhance early departure from the flower or inflorescence, reducing geitonogamy. To examine the adaptive significance of multiple nectar-producing spurs within flowers, we related intraflower variation in nectar characteristics to pollinator foraging behavior and plant reproductive success in protandrous Aquilegia buergeriana var. oxysepala. METHODS We investigated if nectar volume and sugar mass relate to spur length and if intraflower variation in nectar characteristics differ between male- and female-phase flowers. Because male function requires more pollinator visits than female function, male-phase flowers are expected to have greater nectar volume and lower intraflower variation in nectar volume than female-phase flowers. We used intraflower variation in spur length as an indicator of variation in nectar characteristics and investigated how spur length variation affects pollinator behavior, pollen removal, and seed production. KEY RESULTS Male-phase flowers had greater nectar volume and lower intraflower variation in nectar volume than female-phase flowers. Intraflower variation in spur length reduced the duration of bumblebee visits. Short visits reduced seed production, but increased pollen removal. CONCLUSIONS Our results suggest that high intraflower variation in nectar production rate can reduce geitonogamy and potentially increase the genetic diversity of pollen received. Such pattern of nectar secretion within and among flowers may allow flowers to ensure effective pollen transfer or high seed production.
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Affiliation(s)
- Ando Misaki
- Graduate School of Life Sciences, Tohoku University, 6-3 Aoba, Sendai, 980-8578, Japan
| | - Tomoyuki Itagaki
- Graduate School of Life Sciences, Tohoku University, 6-3 Aoba, Sendai, 980-8578, Japan
| | - Yutaka Matsubara
- Graduate School of Life Sciences, Tohoku University, 6-3 Aoba, Sendai, 980-8578, Japan
| | - Satoki Sakai
- Graduate School of Life Sciences, Tohoku University, 6-3 Aoba, Sendai, 980-8578, Japan
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24
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Haverkamp A, Hansson BS, Baldwin IT, Knaden M, Yon F. Floral Trait Variations Among Wild Tobacco Populations Influence the Foraging Behavior of Hawkmoth Pollinators. Front Ecol Evol 2018. [DOI: 10.3389/fevo.2018.00019] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Yon F, Kessler D, Joo Y, Kim SG, Baldwin IT. Fitness consequences of a clock pollinator filter in Nicotiana attenuata flowers in nature. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2017; 59:805-809. [PMID: 28834357 DOI: 10.1111/jipb.12579] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 08/17/2017] [Indexed: 06/07/2023]
Abstract
Nicotiana attenuata flowers, diurnally open, emit scents and move vertically to interact with nocturnal hawkmoth and day-active hummingbird pollinators. To examine the fitness consequences of these floral rhythms, we conducted pollination trials in the plant's native habitat with phase-shifted flowers of plants silenced in circadian clock genes. The results revealed that some pollination benefits observed under glasshouse conditions were not reproduced under natural field conditions. Floral arrhythmicity increased pollination success by hummingbirds, while reducing those by hawkmoths in the field. Thus, floral circadian rhythms may influence a plant's fitness by filtering pollinators leading to altered seed set from outcrossed pollen.
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Affiliation(s)
- Felipe Yon
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
| | - Danny Kessler
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
| | - Youngsung Joo
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
| | - Sang-Gyu Kim
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
- Center for Genome Engineering, Institute for Basic Science, Yuseong-gu, 34047 Daejeon, South Korea
| | - Ian T Baldwin
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
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26
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Palmer-Young EC, Tozkar CÖ, Schwarz RS, Chen Y, Irwin RE, Adler LS, Evans JD. Nectar and Pollen Phytochemicals Stimulate Honey Bee (Hymenoptera: Apidae) Immunity to Viral Infection. JOURNAL OF ECONOMIC ENTOMOLOGY 2017; 110:1959-1972. [PMID: 28981688 DOI: 10.1093/jee/tox193] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Indexed: 05/10/2023]
Affiliation(s)
| | - Cansu Ö Tozkar
- Bee Research Lab, Agricultural Research Service, US Department of Agriculture, Beltsville, MD
| | - Ryan S Schwarz
- Bee Research Lab, Agricultural Research Service, US Department of Agriculture, Beltsville, MD
| | - Yanping Chen
- Bee Research Lab, Agricultural Research Service, US Department of Agriculture, Beltsville, MD
| | - Rebecca E Irwin
- Department of Applied Ecology, North Carolina State University, Raleigh, NC 27695
| | - Lynn S Adler
- Department of Biology, University of Massachusetts, Amherst, MA
| | - Jay D Evans
- Bee Research Lab, Agricultural Research Service, US Department of Agriculture, Beltsville, MD
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27
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Pappas ML, Broekgaarden C, Broufas GD, Kant MR, Messelink GJ, Steppuhn A, Wäckers F, van Dam NM. Induced plant defences in biological control of arthropod pests: a double-edged sword. PEST MANAGEMENT SCIENCE 2017; 73:1780-1788. [PMID: 28387028 PMCID: PMC5575458 DOI: 10.1002/ps.4587] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Revised: 03/31/2017] [Accepted: 03/31/2017] [Indexed: 05/21/2023]
Abstract
Biological control is an important ecosystem service delivered by natural enemies. Together with breeding for plant defence, it constitutes one of the most promising alternatives to pesticides for controlling herbivores in sustainable crop production. Especially induced plant defences may be promising targets in plant breeding for resistance against arthropod pests. Because they are activated upon herbivore damage, costs are only incurred when defence is needed. Moreover, they can be more specific than constitutive defences. Nevertheless, inducible defence traits that are harming plant pest organisms may interfere with biological control agents, such as predators and parasitoids. Despite the vast fundamental knowledge on plant defence mechanisms and their effects on natural enemies, our understanding of the feasibility of combining biological control with induced plant defence in practice is relatively poor. In this review, we focus on arthropod pest control and present the most important features of biological control with natural enemies and of induced plant defence. Furthermore, we show potential synergies and conflicts among them and, finally, identify gaps and list opportunities for their combined use in crop protection. We suggest that breeders should focus on inducible resistance traits that are compatible with the natural enemies of arthropod pests, specifically traits that help communities of natural enemies to build up. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Maria L Pappas
- Democritus University of Thrace, Faculty of Agricultural and Forestry SciencesDepartment of Agricultural DevelopmentOrestiadaGreece
| | - Colette Broekgaarden
- Utrecht University, Faculty of ScienceDepartment of Biology, Plant − Microbe InteractionsUtrechtThe Netherlands
| | - George D Broufas
- Democritus University of Thrace, Faculty of Agricultural and Forestry SciencesDepartment of Agricultural DevelopmentOrestiadaGreece
| | - Merijn R Kant
- University of AmsterdamInstitute for Biodiversity and Ecosystem Dynamics, Section Molecular and Chemical EcologyAmsterdamThe Netherlands
| | | | - Anke Steppuhn
- Freie Universität BerlinInstitute of Biology, Molecular Ecology, Dahlem Centre of Plant SciencesBerlinGermany
| | - Felix Wäckers
- BiobestWesterloBelgium
- Lancaster UniversityLancaster Environment CentreUK
| | - Nicole M van Dam
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐LeipzigLeipzigGermany
- Friedrich Schiller University JenaInstitute of EcologyJenaGermany
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Palmer-Young EC, Hogeboom A, Kaye AJ, Donnelly D, Andicoechea J, Connon SJ, Weston I, Skyrm K, Irwin RE, Adler LS. Context-dependent medicinal effects of anabasine and infection-dependent toxicity in bumble bees. PLoS One 2017; 12:e0183729. [PMID: 28832668 PMCID: PMC5568382 DOI: 10.1371/journal.pone.0183729] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 08/09/2017] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Floral phytochemicals are ubiquitous in nature, and can function both as antimicrobials and as insecticides. Although many phytochemicals act as toxins and deterrents to consumers, the same chemicals may counteract disease and be preferred by infected individuals. The roles of nectar and pollen phytochemicals in pollinator ecology and conservation are complex, with evidence for both toxicity and medicinal effects against parasites. However, it remains unclear how consistent the effects of phytochemicals are across different parasite lineages and environmental conditions, and whether pollinators actively self-medicate with these compounds when infected. APPROACH Here, we test effects of the nectar alkaloid anabasine, found in Nicotiana, on infection intensity, dietary preference, and survival and performance of bumble bees (Bombus impatiens). We examined variation in the effects of anabasine on infection with different lineages of the intestinal parasite Crithidia under pollen-fed and pollen-starved conditions. RESULTS We found that anabasine did not reduce infection intensity in individual bees infected with any of four Crithidia lineages that were tested in parallel, nor did anabasine reduce infection intensity in microcolonies of queenless workers. In addition, neither anabasine nor its isomer, nicotine, was preferred by infected bees in choice experiments, and infected bees consumed less anabasine than did uninfected bees under no-choice conditions. Furthermore, anabasine exacerbated the negative effects of infection on bee survival and microcolony performance. Anabasine reduced infection in only one experiment, in which bees were deprived of pollen and post-pupal contact with nestmates. In this experiment, anabasine had antiparasitic effects in bees from only two of four colonies, and infected bees exhibited reduced-rather than increased-phytochemical consumption relative to uninfected bees. CONCLUSIONS Variation in the effect of anabasine on infection suggests potential modulation of tritrophic interactions by both host genotype and environmental variables. Overall, our results demonstrate that Bombus impatiens prefer diets without nicotine and anabasine, and suggest that the medicinal effects and toxicity of anabasine may be context dependent. Future research should identify the specific environmental and genotypic factors that determine whether nectar phytochemicals have medicinal or deleterious effects on pollinators.
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Affiliation(s)
- Evan C. Palmer-Young
- Organismic & Evolutionary Biology, University of Massachusetts, Amherst, Massachusetts, United States of America
- Department of Biology, University of Massachusetts, Amherst, Massachusetts, United States of America
| | - Alison Hogeboom
- Department of Biology, University of Massachusetts, Amherst, Massachusetts, United States of America
| | - Alexander J. Kaye
- Department of Biology, Dartmouth College, Hanover, New Hampshire, United States of America
| | - Dash Donnelly
- Department of Biology, Dartmouth College, Hanover, New Hampshire, United States of America
| | - Jonathan Andicoechea
- Department of Biology, Dartmouth College, Hanover, New Hampshire, United States of America
| | - Sara June Connon
- Department of Biology, University of Massachusetts, Amherst, Massachusetts, United States of America
- Department of Applied Ecology, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Ian Weston
- Department of Biology, University of Massachusetts, Amherst, Massachusetts, United States of America
| | - Kimberly Skyrm
- Department of Biology, University of Massachusetts, Amherst, Massachusetts, United States of America
| | - Rebecca E. Irwin
- Department of Biology, Dartmouth College, Hanover, New Hampshire, United States of America
- Department of Applied Ecology, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Lynn S. Adler
- Department of Biology, University of Massachusetts, Amherst, Massachusetts, United States of America
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29
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Li R, Wang M, Wang Y, Schuman MC, Weinhold A, Schäfer M, Jiménez-Alemán GH, Barthel A, Baldwin IT. Flower-specific jasmonate signaling regulates constitutive floral defenses in wild tobacco. Proc Natl Acad Sci U S A 2017; 114:E7205-E7214. [PMID: 28784761 PMCID: PMC5576791 DOI: 10.1073/pnas.1703463114] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Optimal defense (OD) theory predicts that within a plant, tissues are defended in proportion to their fitness value and risk of predation. The fitness value of leaves varies greatly and leaves are protected by jasmonate (JA)-inducible defenses. Flowers are vehicles of Darwinian fitness in flowering plants and are attacked by herbivores and pathogens, but how they are defended is rarely investigated. We used Nicotiana attenuata, an ecological model plant with well-characterized herbivore interactions to characterize defense responses in flowers. Early floral stages constitutively accumulate greater amounts of two well-characterized defensive compounds, the volatile (E)-α-bergamotene and trypsin proteinase inhibitors (TPIs), which are also found in herbivore-induced leaves. Plants rendered deficient in JA biosynthesis or perception by RNA interference had significantly attenuated floral accumulations of defensive compounds known to be regulated by JA in leaves. By RNA-seq, we found a JAZ gene, NaJAZi, specifically expressed in early-stage floral tissues. Gene silencing revealed that NaJAZi functions as a flower-specific jasmonate repressor that regulates JAs, (E)-α-bergamotene, TPIs, and a defensin. Flowers silenced in NaJAZi are more resistant to tobacco budworm attack, a florivore. When the defensin was ectopically expressed in leaves, performance of Manduca sexta larvae, a folivore, decreased. NaJAZi physically interacts with a newly identified NINJA-like protein, but not the canonical NINJA. This NINJA-like recruits the corepressor TOPLESS that contributes to the suppressive function of NaJAZi on floral defenses. This study uncovers the defensive function of JA signaling in flowers, which includes components that tailor JA signaling to provide flower-specific defense.
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Affiliation(s)
- Ran Li
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany
| | - Ming Wang
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany
| | - Yang Wang
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany
| | - Meredith C Schuman
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany
| | - Arne Weinhold
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany
| | - Martin Schäfer
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany
| | | | - Andrea Barthel
- Department of Entomology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany
| | - Ian T Baldwin
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany;
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30
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Xu S, Brockmöller T, Navarro-Quezada A, Kuhl H, Gase K, Ling Z, Zhou W, Kreitzer C, Stanke M, Tang H, Lyons E, Pandey P, Pandey SP, Timmermann B, Gaquerel E, Baldwin IT. Wild tobacco genomes reveal the evolution of nicotine biosynthesis. Proc Natl Acad Sci U S A 2017; 114:6133-6138. [PMID: 28536194 PMCID: PMC5468653 DOI: 10.1073/pnas.1700073114] [Citation(s) in RCA: 108] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Nicotine, the signature alkaloid of Nicotiana species responsible for the addictive properties of human tobacco smoking, functions as a defensive neurotoxin against attacking herbivores. However, the evolution of the genetic features that contributed to the assembly of the nicotine biosynthetic pathway remains unknown. We sequenced and assembled genomes of two wild tobaccos, Nicotiana attenuata (2.5 Gb) and Nicotiana obtusifolia (1.5 Gb), two ecological models for investigating adaptive traits in nature. We show that after the Solanaceae whole-genome triplication event, a repertoire of rapidly expanding transposable elements (TEs) bloated these Nicotiana genomes, promoted expression divergences among duplicated genes, and contributed to the evolution of herbivory-induced signaling and defenses, including nicotine biosynthesis. The biosynthetic machinery that allows for nicotine synthesis in the roots evolved from the stepwise duplications of two ancient primary metabolic pathways: the polyamine and nicotinamide adenine dinucleotide (NAD) pathways. In contrast to the duplication of the polyamine pathway that is shared among several solanaceous genera producing polyamine-derived tropane alkaloids, we found that lineage-specific duplications within the NAD pathway and the evolution of root-specific expression of the duplicated Solanaceae-specific ethylene response factor that activates the expression of all nicotine biosynthetic genes resulted in the innovative and efficient production of nicotine in the genus Nicotiana Transcription factor binding motifs derived from TEs may have contributed to the coexpression of nicotine biosynthetic pathway genes and coordinated the metabolic flux. Together, these results provide evidence that TEs and gene duplications facilitated the emergence of a key metabolic innovation relevant to plant fitness.
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Affiliation(s)
- Shuqing Xu
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany;
| | - Thomas Brockmöller
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Aura Navarro-Quezada
- Centre for Organismal Studies, University of Heidelberg, 69120 Heidelberg, Germany
| | - Heiner Kuhl
- Sequencing Core Facility, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | - Klaus Gase
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Zhihao Ling
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Wenwu Zhou
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
| | - Christoph Kreitzer
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany
- Institute of Animal Nutrition and Functional Plant Compounds, University of Veterinary Medicine, 1210 Vienna, Austria
| | - Mario Stanke
- Institute for Mathematics and Computer Science, Universität Greifswald, 17489 Greifswald, Germany
| | - Haibao Tang
- Center for Genomics and Biotechnology, Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology, Fujian Agriculture and Forestry University, 350002 Fuzhou, Fujian, China
| | - Eric Lyons
- School of Plant Sciences, BIO5 Institute, CyVerse, University of Arizona, Tucson, AZ 85721
| | - Priyanka Pandey
- National Institute of Biomedical Genomics, Kalyani, 741251 West Bengal, India
| | - Shree P Pandey
- Department of Biological Sciences, Indian Institute of Science Education and Research-Kolkata, Mohanpur, 700064 West Bengal, India
| | - Bernd Timmermann
- Sequencing Core Facility, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | - Emmanuel Gaquerel
- Centre for Organismal Studies, University of Heidelberg, 69120 Heidelberg, Germany;
| | - Ian T Baldwin
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany;
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31
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Baracchi D, Marples A, Jenkins AJ, Leitch AR, Chittka L. Nicotine in floral nectar pharmacologically influences bumblebee learning of floral features. Sci Rep 2017; 7:1951. [PMID: 28512323 PMCID: PMC5434031 DOI: 10.1038/s41598-017-01980-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 04/06/2017] [Indexed: 01/19/2023] Open
Abstract
Many plants defend themselves against herbivores by chemical deterrents in their tissues and the presence of such substances in floral nectar means that pollinators often encounter them when foraging. The effect of such substances on the foraging behaviour of pollinators is poorly understood. Using artificial flowers in tightly-controlled laboratory settings, we examined the effects of the alkaloid nicotine on bumblebee foraging performance. We found that bumblebees confronted simultaneously with two equally rewarded nicotine-containing and nicotine-free flower types are deterred only by unnaturally high nicotine concentrations. This deterrence disappears or even turns into attraction at lower nectar-relevant concentrations. The alkaloid has profound effects on learning in a dose-dependent manner. At a high natural dose, bees learn the colour of a nicotine-containing flower type more swiftly than a flower type with the same caloric value but without nicotine. Furthermore, after experiencing flowers containing nicotine in any tested concentration, increasing numbers of bumblebees stay more faithful to these flowers, even if they become a suboptimal choice in terms of reward. These results demonstrate that alkaloids enhance pollinator flower constancy, opening new perspectives in co-evolutionary process between plants and pollinators.
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Affiliation(s)
- D Baracchi
- Queen Mary University of London, Department of Biological and Experimental Psychology, School of Biological and Chemical Sciences, Mile End Road, London, E1 4NS, UK.
- Research Centre on Animal Cognition, Center for Integrative Biology, CNRS, University of Toulouse, 118 route de Narbonne, F-31062, Toulouse cedex 09, France.
| | - A Marples
- University College London, Department of Genetics, Evolution and Environment, Faculty of Life Sciences, Gower Street, London, WC1E 6BT, UK
| | - A J Jenkins
- Queen Mary University of London, Department of Biological and Experimental Psychology, School of Biological and Chemical Sciences, Mile End Road, London, E1 4NS, UK
| | - A R Leitch
- Queen Mary University of London, Department of Biological and Experimental Psychology, School of Biological and Chemical Sciences, Mile End Road, London, E1 4NS, UK
| | - L Chittka
- Queen Mary University of London, Department of Biological and Experimental Psychology, School of Biological and Chemical Sciences, Mile End Road, London, E1 4NS, UK
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32
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Tiedge K, Lohaus G. Nectar sugars and amino acids in day- and night-flowering Nicotiana species are more strongly shaped by pollinators' preferences than organic acids and inorganic ions. PLoS One 2017; 12:e0176865. [PMID: 28467507 PMCID: PMC5415175 DOI: 10.1371/journal.pone.0176865] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 04/18/2017] [Indexed: 11/18/2022] Open
Abstract
Floral nectar contains mainly sugars but also amino acids, organic acids, inorganic ions and secondary compounds to attract pollinators. The genus Nicotiana exhibits great diversity among species in floral morphology, flowering time, nectar compositions, and predominant pollinators. We studied nectar samples of 20 Nicotiana species, composed equally of day- and night-flowering plants and attracting different groups of pollinators (e.g. hummingbirds, moths or bats) to investigate whether sugars, amino acids, organic acids and inorganic ions are influenced by pollinator preferences. Glucose, fructose and sucrose were the only sugars found in the nectar of all examined species. Sugar concentration of the nectar of day-flowering species was 20% higher and amino acid concentration was 2-3-fold higher compared to the nectar of night-flowering species. The sucrose-to-hexose ratio was significantly higher in night-flowering species and the relative share of sucrose based on the total sugar correlated with the flower tube length in the nocturnal species. Flowers of different tobacco species contained varying volumes of nectar which led to about 150-fold higher amounts of total sugar per flower in bat- or sunbird-pollinated species than in bee-pollinated or autogamous species. This difference was even higher for total amino acids per flower (up to 1000-fold). As a consequence, some Nicotiana species invest large amounts of organic nitrogen for certain pollinators. Higher concentrations of inorganic ions, predominantly anions, were found in nectar of night-flowering species. Therefore, higher anion concentrations were also associated with pollinator types active at night. Malate, the main organic acid, was present in all nectar samples but the concentration was not correlated with pollinator type. In conclusion, statistical analyses revealed that pollinator types have a stronger effect on nectar composition than phylogenetic relations. In this context, nectar sugars and amino acids are more strongly correlated with the preferences of predominant pollinators than organic acids and inorganic ions.
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Affiliation(s)
- Kira Tiedge
- Molecular Plant Science/ Plant Biochemistry, University of Wuppertal, Wuppertal, Germany
| | - Gertrud Lohaus
- Molecular Plant Science/ Plant Biochemistry, University of Wuppertal, Wuppertal, Germany
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33
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Borghi M, Fernie AR, Schiestl FP, Bouwmeester HJ. The Sexual Advantage of Looking, Smelling, and Tasting Good: The Metabolic Network that Produces Signals for Pollinators. TRENDS IN PLANT SCIENCE 2017; 22:338-350. [PMID: 28111171 DOI: 10.1016/j.tplants.2016.12.009] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 12/10/2016] [Accepted: 12/21/2016] [Indexed: 05/08/2023]
Abstract
A striking feature of the angiosperms that use animals as pollen carriers to sexually reproduce is the great diversity of their flowers with regard to morphology and traits such as color, odor, and nectar. These traits are underpinned by the synthesis of secondary metabolites such as pigments and volatiles, as well as carbohydrates and amino acids, which are used by plants to lure and reward animal pollinators. We review here the knowledge of the metabolic network that supports the biosynthesis of these compounds and the behavioral responses that these molecules elicit in the animal pollinators. Such knowledge provides us with a deeper insight into the ecology and evolution of plant-pollinator interactions, and should help us to better manage these ecologically essential interactions in agricultural ecosystems.
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Affiliation(s)
- Monica Borghi
- Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, Am Muehlenberg 1, 14476, Potsdam-Golm, Germany
| | - Florian P Schiestl
- Department of Systematic and Evolutionary Botany, University of Zürich, Zollikerstrasse 107, 8008 Zürich
| | - Harro J Bouwmeester
- Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands; Present address: Plant Hormone Biology group, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
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34
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Yon F, Kessler D, Joo Y, Cortés Llorca L, Kim SG, Baldwin IT. Fitness consequences of altering floral circadian oscillations for Nicotiana attenuata. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2017; 59:180-189. [PMID: 27957809 DOI: 10.1111/jipb.12511] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 12/12/2016] [Indexed: 06/06/2023]
Abstract
Ecological interactions between flowers and pollinators are all about timing. Flower opening/closing and scent emissions are largely synchronized with pollinator activity, and a circadian clock regulates these rhythms. However, whether the circadian clock increases a plant's reproductive success by regulating these floral rhythms remains untested. Flowers of Nicotiana attenuata, a wild tobacco, diurnally and rhythmically open, emit scent and move vertically through a 140° arc to interact with nocturnal hawkmoths. We tethered flowers to evaluate the importance of flower positions for Manduca sexta-mediated pollinations; flower position dramatically influenced pollination. We examined the pollination success of phase-shifted flowers, silenced in circadian clock genes, NaZTL, NaLHY, and NaTOC1, by RNAi. Circadian rhythms in N. attenuata flowers are responsible for altered seed set from outcrossed pollen.
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Affiliation(s)
- Felipe Yon
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
| | - Danny Kessler
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
| | - Youngsung Joo
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
| | - Lucas Cortés Llorca
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
| | - Sang-Gyu Kim
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
- Center for Genome Engineering, Institute for Basic Science, Yuseong-gu, 34047 Daejeon, South Korea
| | - Ian T Baldwin
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
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35
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Andersson KM, Turkkila M, Erlandsson MC, Bossios A, Silfverswärd ST, Hu D, Ekerljung L, Malmhäll C, Weiner HL, Lundbäck B, Bokarewa MI. Survivin controls biogenesis of microRNA in smokers: A link to pathogenesis of rheumatoid arthritis. Biochim Biophys Acta Mol Basis Dis 2017; 1863:663-673. [DOI: 10.1016/j.bbadis.2016.11.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 11/21/2016] [Accepted: 11/30/2016] [Indexed: 12/14/2022]
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36
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Detoxification and elimination of nicotine by nectar-feeding birds. J Comp Physiol B 2017; 187:591-602. [PMID: 28150179 DOI: 10.1007/s00360-016-1055-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 11/18/2016] [Accepted: 11/29/2016] [Indexed: 01/19/2023]
Abstract
Many dilute nectars consumed by bird pollinators contain secondary metabolites, potentially toxic chemicals produced by plants as defences against herbivores. Consequently, nectar-feeding birds are challenged not only by frequent water excess, but also by the toxin content of their diet. High water turnover, however, could be advantageous to nectar consumers by enabling them to excrete secondary metabolites or their transformation products more easily. We investigated how the alkaloid nicotine, naturally present in nectar of Nicotiana species, influences osmoregulation in white-bellied sunbirds Cinnyris talatala and Cape white-eyes Zosterops virens. We also examined the metabolic fate of nicotine in these two species to shed more light on the post-ingestive mechanisms that allow nectar-feeding birds to tolerate nectar nicotine. A high concentration of nicotine (50 µM) decreased cloacal fluid output and increased its osmolality in both species, due to reduced food intake that led to dehydration. White-eyes excreted a higher proportion of the ingested nicotine-containing diet than sunbirds. However, sugar concentration did not affect nicotine detoxification and elimination. Both species metabolised nicotine, excreting very little unchanged nicotine. Cape white-eyes mainly metabolised nicotine through the cotinine metabolic pathway, with norcotinine being the most abundant metabolite in the excreta, while white-bellied sunbirds excreted mainly nornicotine. Both species also utilized phase II conjugation reactions to detoxify nicotine, with Cape white-eyes depending more on the mercapturic acid pathway to detoxify nicotine than white-bellied sunbirds. We found that sunbirds and white-eyes, despite having a similar nicotine tolerance, responded differently and used different nicotine-derived metabolites to excrete nicotine.
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37
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Bumble bee parasite strains vary in resistance to phytochemicals. Sci Rep 2016; 6:37087. [PMID: 27883009 PMCID: PMC5121629 DOI: 10.1038/srep37087] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 10/14/2016] [Indexed: 12/05/2022] Open
Abstract
Nectar and pollen contain diverse phytochemicals that can reduce disease in pollinators. However, prior studies showed variable effects of nectar chemicals on infection, which could reflect variable phytochemical resistance among parasite strains. Inter-strain variation in resistance could influence evolutionary interactions between plants, pollinators, and pollinator disease, but testing direct effects of phytochemicals on parasites requires elimination of variation between bees. Using cell cultures of the bumble bee parasite Crithidia bombi, we determined (1) growth-inhibiting effects of nine floral phytochemicals and (2) variation in phytochemical resistance among four parasite strains. C. bombi growth was unaffected by naturally occurring concentrations of the known antitrypanosomal phenolics gallic acid, caffeic acid, and chlorogenic acid. However, C. bombi growth was inhibited by anabasine, eugenol, and thymol. Strains varied >3-fold in phytochemical resistance, suggesting that selection for phytochemical resistance could drive parasite evolution. Inhibitory concentrations of thymol (4.53–22.2 ppm) were similar to concentrations in Thymus vulgaris nectar (mean 5.2 ppm). Exposure of C. bombi to naturally occurring levels of phytochemicals—either within bees or during parasite transmission via flowers—could influence infection in nature. Flowers that produce antiparasitic phytochemicals, including thymol, could potentially reduce infection in Bombus populations, thereby counteracting a possible contributor to pollinator decline.
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38
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Liedschulte V, Schwaar JD, Laparra H, Vuarnoz A, Philippon B, Bakaher N, Sierro N, Bovet L, Lang G, Goepfert S. Identification of CYP82E21 as a functional nicotine N-demethylase in tobacco flowers. PHYTOCHEMISTRY 2016; 131:9-16. [PMID: 27596288 DOI: 10.1016/j.phytochem.2016.08.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/08/2016] [Accepted: 08/14/2016] [Indexed: 05/25/2023]
Abstract
In the tobacco plant, nicotine N-demethylase enzymes (NND) belonging to the cytochrome P450 family catalyse the conversion of nicotine to nornicotine, the precursor of the carcinogenic tobacco-specific N-nitrosamine, N-nitrosonornicotine. To date three demethylase genes, namely CYP82E4, CYP82E5 and CYP82E10, have been shown to be involved in this process, while the related CYP82E2 and CYP82E3 genes are not functional. We have identified a further gene named CYP82E21 encoding a putative nicotine N-demethylase closely related to the CYP82E genes. The CYP82E21 gene was found in all Nicotiana tabacum cultivars analysed and originates from the tobacco ancestor Nicotiana tomentosiformis. We show that, in contrast to all other previously characterized NND genes, CYP82E21 is not expressed in green or senescent leaves, but in flowers, more specifically in ovaries. The nicotine N-demethylase activity of CYP82E21 was confirmed by ectopic expression of the coding sequence in a tobacco line lacking functional CYP82E4, CYP82E5 and CYP82E10 genes, resulting in an eightfold increase of nicotine demethylation compared to the control plants. Furthermore, nornicotine formation can be reduced in ovaries by introducing a CYP82E21-specific RNAi construct. Together, our results demonstrate that the CYP82E21 gene encodes a functional ovary-specific nicotine N-demethylase.
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Affiliation(s)
- Verena Liedschulte
- PMI R&D, Philip Morris Products SA, (part of Philip Morris International Group of Companies), Neuchâtel, Switzerland.
| | - Joanne Deborah Schwaar
- PMI R&D, Philip Morris Products SA, (part of Philip Morris International Group of Companies), Neuchâtel, Switzerland.
| | - Hélène Laparra
- PMI R&D, Philip Morris Products SA, (part of Philip Morris International Group of Companies), Neuchâtel, Switzerland.
| | - Aline Vuarnoz
- PMI R&D, Philip Morris Products SA, (part of Philip Morris International Group of Companies), Neuchâtel, Switzerland.
| | - Bérangère Philippon
- PMI R&D, Philip Morris Products SA, (part of Philip Morris International Group of Companies), Neuchâtel, Switzerland.
| | - Nicolas Bakaher
- PMI R&D, Philip Morris Products SA, (part of Philip Morris International Group of Companies), Neuchâtel, Switzerland.
| | - Nicolas Sierro
- PMI R&D, Philip Morris Products SA, (part of Philip Morris International Group of Companies), Neuchâtel, Switzerland.
| | - Lucien Bovet
- PMI R&D, Philip Morris Products SA, (part of Philip Morris International Group of Companies), Neuchâtel, Switzerland.
| | - Gerhard Lang
- PMI R&D, Philip Morris Products SA, (part of Philip Morris International Group of Companies), Neuchâtel, Switzerland.
| | - Simon Goepfert
- PMI R&D, Philip Morris Products SA, (part of Philip Morris International Group of Companies), Neuchâtel, Switzerland.
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39
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Stevenson PC, Nicolson SW, Wright GA. Plant secondary metabolites in nectar: impacts on pollinators and ecological functions. Funct Ecol 2016. [DOI: 10.1111/1365-2435.12761] [Citation(s) in RCA: 165] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Philip C. Stevenson
- Royal Botanic Gardens, Kew SurreyTW9 3AB UK
- Natural Resources Institute University of Greenwich KentME4 4TB UK
| | - Susan W. Nicolson
- Department of Zoology & Entomology University of Pretoria Private Bag X20 Hatfield0028 South Africa
| | - Geraldine A. Wright
- Centre for Behaviour and Evolution Institute of Neuroscience Newcastle University Newcastle upon TyneNE1 7RU UK
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40
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Kaczorowski RL, Markman S. Nectar alkaloids of tree tobacco can reduce Palestine sunbird foraging performance in a colour discrimination task. Anim Behav 2016. [DOI: 10.1016/j.anbehav.2016.05.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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41
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Stanton MA, Preβler J, Paetz C, Boland W, Svatoš A, Baldwin IT. Plant-mediated pheromone emission by a hemipteran seed feeder increases the apparency of an unreliable but rewarding host. THE NEW PHYTOLOGIST 2016; 211:113-25. [PMID: 26915986 DOI: 10.1111/nph.13879] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 12/26/2015] [Indexed: 06/05/2023]
Abstract
The defensive chemistry and persistence of plant tissues determine their suitability and apparency - the likelihood of being discovered - to insect herbivores. As consumers of plant tissues with transient apparency, florivores and seed-feeders must frequently migrate between host plants to synchronize colonization with plant phenology. Aggregation pheromones could provide information-based solutions to finding ephemeral hosts, but little is known about plant-influenced variation in this form of chemical communication. Combining analytical chemistry, de novo synthesis and field ecology, we investigated the change in colonization of two sympatric host plants, Nicotiana attenuata and Nicotiana obtusifolia, which differ in apparency-related life history traits, by a heteropteran seed-feeder, Corimelaena extensa. We identified a novel pheromone released by C. extensa males - (5Z,8Z)-tetradeca-5,8-dienal - and performed field assays with the synthetic pheromone, showing that it stimulates the formation of feeding aggregations on the post-fire annual N. attenuata. Corimelaena extensa pheromone emission was 40-fold higher when feeding on N. attenuata compared with the perennial N. obtusifolia, as were adult fecundity and seed capsule content of the putative biosynthetic precursor, linoleic acid. Higher pheromone emission increases the apparency and colonization of the ephemeral, high-quality host N. attenuata. This plant-specific variation in insect signaling could facilitate host-finding by seed-feeders migrating between plant patches.
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Affiliation(s)
- Mariana A Stanton
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straβe 8, 07745, Jena, Germany
| | - Jens Preβler
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straβe 8, 07745, Jena, Germany
| | - Christian Paetz
- Research Group Biosynthesis/NMR, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straβe 8, 07745, Jena, Germany
| | - Wilhelm Boland
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straβe 8, 07745, Jena, Germany
| | - Aleš Svatoš
- Research Group Mass Spectrometry/Proteomics, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straβe 8, 07745, Jena, Germany
| | - Ian T Baldwin
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straβe 8, 07745, Jena, Germany
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42
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Vannette RL, Fukami T. Nectar microbes can reduce secondary metabolites in nectar and alter effects on nectar consumption by pollinators. Ecology 2016; 97:1410-9. [DOI: 10.1890/15-0858.1] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Rachel L. Vannette
- Department of Biology Stanford University Stanford California 94305‐5020 USA
| | - Tadashi Fukami
- Department of Biology Stanford University Stanford California 94305‐5020 USA
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43
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Richardson LL, Bowers MD, Irwin RE. Nectar chemistry mediates the behavior of parasitized bees: consequences for plant fitness. Ecology 2016; 97:325-37. [DOI: 10.1890/15-0263.1] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Leif L. Richardson
- Department of Biological Sciences Dartmouth College Hanover New Hampshire 03755 USA
| | - M. Deane Bowers
- Ecology and Evolutionary Biology and Museum of Natural History University of Colorado at Boulder UCB 334 Boulder Colorado 80309 USA
| | - Rebecca E. Irwin
- Department of Biological Sciences Dartmouth College Hanover New Hampshire 03755 USA
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44
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Caruso CM, Parachnowitsch AL. Do Plants Eavesdrop on Floral Scent Signals? TRENDS IN PLANT SCIENCE 2016; 21:9-15. [PMID: 26476624 DOI: 10.1016/j.tplants.2015.09.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 09/02/2015] [Accepted: 09/07/2015] [Indexed: 05/18/2023]
Abstract
Plants emit a diverse array of volatile organic compounds that can function as cues to other plants. Plants can use volatiles emitted by neighbors to gain information about their environment, and respond by adjusting their phenotype. Less is known about whether the many different volatile signals that plants emit are all equally likely to function as cues to other plants. We review evidence for the function of floral volatile signals and conclude that plants are as likely to perceive and respond to floral volatiles as to other, better-studied volatiles. We propose that eavesdropping on floral volatile cues is particularly likely to be adaptive because plants can respond to these cues by adjusting traits that directly affect pollination and mating.
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Affiliation(s)
- Christina M Caruso
- Department of Integrative Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
| | - Amy L Parachnowitsch
- Plant Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, 75236 Uppsala, Sweden
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45
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Johnson MT, Campbell SA, Barrett SC. Evolutionary Interactions Between Plant Reproduction and Defense Against Herbivores. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2015. [DOI: 10.1146/annurev-ecolsys-112414-054215] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Marc T.J. Johnson
- Department of Biology, University of Toronto at Mississauga, Mississauga, Ontario, L5L 1C6 Canada;
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, M5S 3B2 Canada; ,
| | - Stuart A. Campbell
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, M5S 3B2 Canada; ,
| | - Spencer C.H. Barrett
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, M5S 3B2 Canada; ,
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Lerch-Henning S, Nicolson S. Effects of nicotine on the digestive performance of nectar-feeding birds reflect their relative tolerance to this alkaloid. Comp Biochem Physiol A Mol Integr Physiol 2015; 190:47-53. [DOI: 10.1016/j.cbpa.2015.08.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 07/20/2015] [Accepted: 08/28/2015] [Indexed: 12/01/2022]
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47
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Poreddy S, Mitra S, Schöttner M, Chandran J, Schneider B, Baldwin IT, Kumar P, Pandit SS. Detoxification of hostplant's chemical defence rather than its anti-predator co-option drives β-glucosidase-mediated lepidopteran counteradaptation. Nat Commun 2015; 6:8525. [PMID: 26443324 PMCID: PMC4633822 DOI: 10.1038/ncomms9525] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 09/02/2015] [Indexed: 11/19/2022] Open
Abstract
The evolutionary plant-herbivore arms race sometimes gives rise to remarkably unique adaptation strategies. Here we report one such strategy in the lepidopteran herbivore Manduca sexta against its hostplant Nicotiana attenuata's major phytotoxins, 17-hydroxygeranyllinalool diterpene glycoside, lyciumoside IV and its malonylated forms. We show that alkalinity of larval regurgitant non-enzymatically demalonylates the malonylated forms to lyciumoside IV. Lyciumoside IV is then detoxified in the midgut by β-glucosidase 1-catalysed deglycosylation, which is unusual, as typically the deglycosylation of glycosylated phytochemicals by insects results in the opposite: toxin activation. Suppression of deglucosylation by silencing larval β-glucosidase 1 by plant-mediated RNAi causes moulting impairments and mortality. In the native habitat of N. attenuata, β-glucosidase 1 silencing also increases larval unpalatability to native predatory spiders, suggesting that the defensive co-option of lyciumoside IV may be ecologically advantageous. We infer that M. sexta detoxifies this allelochemical to avoid its deleterious effects, rather than co-opting it against predators.
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Affiliation(s)
- Spoorthi Poreddy
- Department of Molecular Ecology, Max-Planck-Institute for Chemical Ecology, 07745 Jena, Germany
| | - Sirsha Mitra
- Department of Molecular Ecology, Max-Planck-Institute for Chemical Ecology, 07745 Jena, Germany
| | - Matthias Schöttner
- Department of Molecular Ecology, Max-Planck-Institute for Chemical Ecology, 07745 Jena, Germany
| | - Jima Chandran
- Department of Biosynthesis/NMR Research Group, Max-Planck-Institute for Chemical Ecology, 07745 Jena, Germany
| | - Bernd Schneider
- Department of Biosynthesis/NMR Research Group, Max-Planck-Institute for Chemical Ecology, 07745 Jena, Germany
| | - Ian T. Baldwin
- Department of Molecular Ecology, Max-Planck-Institute for Chemical Ecology, 07745 Jena, Germany
| | - Pavan Kumar
- Department of Molecular Ecology, Max-Planck-Institute for Chemical Ecology, 07745 Jena, Germany
| | - Sagar S. Pandit
- Department of Molecular Ecology, Max-Planck-Institute for Chemical Ecology, 07745 Jena, Germany
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48
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Santhanam R, Luu VT, Weinhold A, Goldberg J, Oh Y, Baldwin IT. Native root-associated bacteria rescue a plant from a sudden-wilt disease that emerged during continuous cropping. Proc Natl Acad Sci U S A 2015; 112:E5013-20. [PMID: 26305938 PMCID: PMC4568709 DOI: 10.1073/pnas.1505765112] [Citation(s) in RCA: 208] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Plants maintain microbial associations whose functions remain largely unknown. For the past 15 y, we have planted the annual postfire tobacco Nicotiana attenuata into an experimental field plot in the plant's native habitat, and for the last 8 y the number of plants dying from a sudden wilt disease has increased, leading to crop failure. Inadvertently we had recapitulated the common agricultural dilemma of pathogen buildup associated with continuous cropping for this native plant. Plants suffered sudden tissue collapse and black roots, symptoms similar to a Fusarium-Alternaria disease complex, recently characterized in a nearby native population and developed into an in vitro pathosystem for N. attenuata. With this in vitro disease system, different protection strategies (fungicide and inoculations with native root-associated bacterial and fungal isolates), together with a biochar soil amendment, were tested further in the field. A field trial with more than 900 plants in two field plots revealed that inoculation with a mixture of native bacterial isolates significantly reduced disease incidence and mortality in the infected field plot without influencing growth, herbivore resistance, or 32 defense and signaling metabolites known to mediate resistance against native herbivores. Tests in a subsequent year revealed that a core consortium of five bacteria was essential for disease reduction. This consortium, but not individual members of the root-associated bacteria community which this plant normally recruits during germination from native seed banks, provides enduring resistance against fungal diseases, demonstrating that native plants develop opportunistic mutualisms with prokaryotes that solve context-dependent ecological problems.
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Affiliation(s)
- Rakesh Santhanam
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Jena 07745, Germany
| | - Van Thi Luu
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Jena 07745, Germany
| | - Arne Weinhold
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Jena 07745, Germany
| | - Jay Goldberg
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Jena 07745, Germany
| | - Youngjoo Oh
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Jena 07745, Germany
| | - Ian T Baldwin
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Jena 07745, Germany
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49
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Li D, Baldwin IT, Gaquerel E. Navigating natural variation in herbivory-induced secondary metabolism in coyote tobacco populations using MS/MS structural analysis. Proc Natl Acad Sci U S A 2015; 112:E4147-55. [PMID: 26170304 PMCID: PMC4522797 DOI: 10.1073/pnas.1503106112] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Natural variation can be extremely useful in unraveling the determinants of phenotypic trait evolution but has rarely been analyzed with unbiased metabolic profiling to understand how its effects are organized at the level of biochemical pathways. Native populations of Nicotiana attenuata, a wild tobacco species, have been shown to be highly genetically diverse for traits important for their interactions with insects. To resolve the chemodiversity existing in these populations, we developed a metabolomics and computational pipeline to annotate leaf metabolic responses to Manduca sexta herbivory. We selected seeds from 43 accessions of different populations from the southwestern United States--including the well-characterized Utah 30th generation inbred accession--and grew 183 plants in the glasshouse for standardized herbivory elicitation. Metabolic profiles were generated from elicited leaves of each plant using a high-throughput ultra HPLC (UHPLC)-quadrupole TOFMS (qTOFMS) method, processed to systematically infer covariation patterns among biochemically related metabolites, as well as unknown ones, and finally assembled to map natural variation. Navigating this map revealed metabolic branch-specific variations that surprisingly only partly overlapped with jasmonate accumulation polymorphisms and deviated from canonical jasmonate signaling. Fragmentation analysis via indiscriminant tandem mass spectrometry (idMS/MS) was conducted with 10 accessions that spanned a large proportion of the variance found in the complete accession dataset, and compound spectra were computationally assembled into spectral similarity networks. The biological information captured by this networking approach facilitates the mining of the mass spectral data of unknowns with high natural variation, as demonstrated by the annotation of a strongly herbivory-inducible phenolic derivative, and can guide pathway analysis.
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Affiliation(s)
- Dapeng Li
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany
| | - Ian T Baldwin
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany
| | - Emmanuel Gaquerel
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, D-07745 Jena, Germany; Centre for Organismal Studies, University of Heidelberg, 69120 Heidelberg, Germany
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50
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Aizenberg-Gershtein Y, Izhaki I, Santhanam R, Kumar P, Baldwin IT, Halpern M. Pyridine-type alkaloid composition affects bacterial community composition of floral nectar. Sci Rep 2015; 5:11536. [PMID: 26122961 PMCID: PMC4650603 DOI: 10.1038/srep11536] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 05/11/2015] [Indexed: 11/16/2022] Open
Abstract
Pyridine-type alkaloids are most common in Nicotiana species. To study the effect of alkaloid composition on bacterial community composition in floral nectar, we compared the nicotine-rich wild type (WT) N. attenuata, the nicotine biosynthesis-silenced N. attenuata that was rich in anatabine and the anabasine-rich WT N. glauca plants. We found that the composition of these secondary metabolites in the floral nectar drastically affected the bacterial community richness, diversity and composition. Significant differences were found between the bacterial community compositions in the nectar of the three plants with a much greater species richness and diversity in the nectar from the transgenic plant. The highest community composition similarity index was detected between the two wild type plants. The different microbiome composition and diversity, caused by the different pyridine-type alkaloid composition, could modify the nutritional content of the nectar and consequently, may contribute to the change in the nectar consumption and visitation. These may indirectly have an effect on plant fitness.
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Affiliation(s)
- Yana Aizenberg-Gershtein
- Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Mount Carmel, Haifa, Israel
| | - Ido Izhaki
- Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Mount Carmel, Haifa, Israel
| | - Rakesh Santhanam
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Pavan Kumar
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Ian T. Baldwin
- Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Malka Halpern
- Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Mount Carmel, Haifa, Israel
- Department of Biology and Environment, Faculty of Natural Sciences, University of Haifa, Oranim, Tivon, Israel
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