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Rasool SG, Abdullah M, Li D, Yanping L. Relationship between secondary metabolites and insect loads in cabbage with different leaf shapes and positions. PHYTOCHEMICAL ANALYSIS : PCA 2024. [PMID: 38923178 DOI: 10.1002/pca.3406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Revised: 06/07/2024] [Accepted: 06/08/2024] [Indexed: 06/28/2024]
Abstract
INTRODUCTION Secondary metabolites in plants play a crucial role in defense mechanisms against insects, pests, and pathogens. These metabolites exhibit varying distributions within and among plant parts under different biotic and abiotic conditions. Understanding the intricate relationships between secondary metabolites and insect populations can be helpful for elucidating plant defense mechanisms and enhancing agricultural managing efficiencies. OBJECTIVE To investigate the influence of the glucosinolate profile in the leaves of three cabbage (Brassica oleracea var. capitata L.) varieties on insect loads. METHODS Glucosinolate profiles across different leaf positions (such as bottom, middle, and center) and leaf shapes (such as curly and non-curly leaf) of three cabbage varieties (Xiagan [XGA], Xiaguang [XGU], and Qiangxia [QIX]) were analyzed by using high-performance liquid chromatography-mass spectrometry (LC-MS). The insect loads were recorded by visually inspecting the upper and lower layers of each target leaf. RESULTS Increasing concentrations of four glucosinolates, namely, glucoiberin, progoitrin, glucoraphanin, and glucobrassicin, were positively related to insect loads. While increasing concentrations of the other four glucosinolates, such as neoglucobrassicin, 4-methoxyglucobrassicin, sinigrin, and gluconapin, were negatively related to insect loads. Furthermore, both glucosinolate synthesis and insect loads were significantly higher in the curly-shaped and middle-position leaves than in the non-curly-shaped and bottom- and central-position leaves across the cabbage varieties. CONCLUSION Differences in glucosinolate profiles across leaf positions and shapes strongly influenced the insect loads of the three Brassica varieties. This link may further extend our understanding of the real defense power of a particular variety against herbivore damage.
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Affiliation(s)
- Samreen Ghulam Rasool
- School of Ecological and Environmental Science, East China Normal University, Shanghai, China
| | - Muhammad Abdullah
- School of Ecological and Environmental Science, East China Normal University, Shanghai, China
| | - Dezhi Li
- School of Ecological and Environmental Science, East China Normal University, Shanghai, China
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai, China
- Institute of Eco-Chongming (IEC), Shanghai, China
- Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai, China
| | - Liu Yanping
- School of Ecological and Environmental Science, East China Normal University, Shanghai, China
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2
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Ye W, Bustos‐Segura C, Degen T, Erb M, Turlings TCJ. Belowground and aboveground herbivory differentially affect the transcriptome in roots and shoots of maize. PLANT DIRECT 2022; 6:e426. [PMID: 35898557 PMCID: PMC9307387 DOI: 10.1002/pld3.426] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 06/20/2022] [Indexed: 05/13/2023]
Abstract
UNLABELLED Plants recognize and respond to feeding by herbivorous insects by upregulating their local and systemic defenses. While defense induction by aboveground herbivores has been well studied, far less is known about local and systemic defense responses against attacks by belowground herbivores. Here, we investigated and compared the responses of the maize transcriptome to belowground and aboveground mechanical damage and infestation by two well-adapted herbivores: the soil-dwelling western corn rootworm Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae) and the leaf-chewing fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae). In responses to both herbivores, maize plants were found to alter local transcription of genes involved in phytohormone signaling, primary and secondary metabolism. Induction by real herbivore damage was considerably stronger and modified the expression of more genes than mechanical damage. Feeding by the corn rootworm had a strong impact on the shoot transcriptome, including the activation of genes involved in defense and development. By contrast, feeding by the fall armyworm induced only few transcriptional changes in the roots. In conclusion, feeding by a leaf chewer and a root feeder differentially affects the local and systemic defense of maize plants. Besides revealing clear differences in how maize plants respond to feeding by these specialized herbivores, this study reveals several novel genes that may play key roles in plant-insect interactions and thus sets the stage for in depth research into the mechanism that can be exploited for improved crop protection. SIGNIFICANCE STATEMENT Extensive transcriptomic analyses revealed a clear distinction between the gene expression profiles in maize plants upon shoot and root attack, locally as well as distantly from the attacked tissue. This provides detailed insights into the specificity of orchestrated plant defense responses, and the dataset offers a molecular resource for further genetic studies on maize resistance to herbivores and paves the way for novel strategies to enhance maize resistance to pests.
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Affiliation(s)
- Wenfeng Ye
- Laboratory of Fundamental and Applied Research in Chemical Ecology, Institute of BiologyUniversity of NeuchâtelNeuchâtelSwitzerland
| | - Carlos Bustos‐Segura
- Laboratory of Fundamental and Applied Research in Chemical Ecology, Institute of BiologyUniversity of NeuchâtelNeuchâtelSwitzerland
| | - Thomas Degen
- Laboratory of Fundamental and Applied Research in Chemical Ecology, Institute of BiologyUniversity of NeuchâtelNeuchâtelSwitzerland
| | - Matthias Erb
- Institute of Plant SciencesUniversity of BernBernSwitzerland
| | - Ted C. J. Turlings
- Laboratory of Fundamental and Applied Research in Chemical Ecology, Institute of BiologyUniversity of NeuchâtelNeuchâtelSwitzerland
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3
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Douglas TE, Beskid SG, Gernand CE, Nirtaut BE, Tamsil KE, Fitch RW, Tarvin RD. Trade-offs between cost of ingestion and rate of intake drive defensive toxin use. Biol Lett 2022; 18:20210579. [PMID: 35135316 PMCID: PMC8826133 DOI: 10.1098/rsbl.2021.0579] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Animals that ingest toxins can become unpalatable and even toxic to predators and parasites through toxin sequestration. Because most animals rapidly eliminate toxins to survive their ingestion, it is unclear how populations transition from susceptibility and toxin elimination to tolerance and accumulation as chemical defence emerges. Studies of chemical defence have generally focused on species with active toxin sequestration and target-site insensitivity mutations or toxin-binding proteins that permit survival without necessitating toxin elimination. Here, we investigate whether animals that presumably rely on toxin elimination for survival can use ingested toxins for defence. We use the A4 and A3 Drosophila melanogaster fly strains from the Drosophila Synthetic Population Resource (DSPR), which respectively possess high and low metabolic nicotine resistance among DSPR fly lines. We find that ingesting nicotine increased A4 but not A3 fly survival against Leptopilina heterotoma wasp parasitism. Further, we find that despite possessing genetic variants that enhance toxin elimination, A4 flies accrued more nicotine than A3 individuals, likely by consuming more medium. Our results suggest that enhanced toxin metabolism can allow greater toxin intake by offsetting the cost of toxin ingestion. Passive toxin accumulation that accompanies increased toxin intake may underlie the early origins of chemical defence.
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Affiliation(s)
- Tyler E. Douglas
- Museum of Vertebrate Zoology and Department of Integrative Biology, University of California Berkeley, 3101 Valley Life Sciences Building, Berkeley, CA 94720, USA
| | - Sofia G. Beskid
- Museum of Vertebrate Zoology and Department of Integrative Biology, University of California Berkeley, 3101 Valley Life Sciences Building, Berkeley, CA 94720, USA,Department of Integrative Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Callie E. Gernand
- Department of Chemistry and Physics, Indiana State University, Terre Haute, IN 47809, USA
| | - Brianna E. Nirtaut
- Department of Chemistry and Physics, Indiana State University, Terre Haute, IN 47809, USA
| | - Kristen E. Tamsil
- Museum of Vertebrate Zoology and Department of Integrative Biology, University of California Berkeley, 3101 Valley Life Sciences Building, Berkeley, CA 94720, USA
| | - Richard W. Fitch
- Department of Chemistry and Physics, Indiana State University, Terre Haute, IN 47809, USA
| | - Rebecca D. Tarvin
- Museum of Vertebrate Zoology and Department of Integrative Biology, University of California Berkeley, 3101 Valley Life Sciences Building, Berkeley, CA 94720, USA
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4
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Sculfort O, Gérard M, Gekière A, Nonclercq D, Gerbaux P, Duez P, Vanderplanck M. Specialized Metabolites in Floral Resources: Effects and Detection in Buff-Tailed Bumblebees. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.669352] [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
The selection of appropriate food resources by bees is a critical aspect for the maintenance of their populations, especially in the current context of global change and pollinator decline. Wild bees have a sophisticated ability to forage selectively on specific resources, and can assess the quality of pollen using contact chemosensory perception (taste). While numerous studies have investigated the detection of pollen macronutrients in bees and their impact on bee health and reproductive success, only a few studies have described the gustatory responses of bees toward specialized metabolites. In addition, these studies mostly focused on the response to nectar and neglected pollen, which is the main food resource for both bee imagines and larvae. Whether bees have the ability to detect specialized toxic metabolites in pollen and then rapidly adapt their foraging behavior to avoid them is very little studied. In this study, we tested whether pollen specialized metabolites affect bumblebees at both the micro-colony and individual levels (i.e., bioassays using supplemented pollen), and whether foragers detect these specialized metabolites and potentially display an avoidance behavior (i.e., preference tests using supplemented syrup). Bumblebees were fed with either amygdalin-, scopolamine- or sinigrin-supplemented pollen diets in ratios that mimic 50%, 100%, and 200% of naturally occurring concentrations. We found no effect of these specialized metabolites on resource collection, reproductive success and stress response at the micro-colony level. At the individual level, bumblebees fed on 50%-amygdalin or 50%-scopolamine diets displayed the highest scores for damage to their digestive systems. Interestingly, during the preference tests, the solution with 50%-scopolamine displayed a phagostimulatory activity, whereas solution with 50%-amygdalin had a deterrent effect and could trigger an active avoidance behavior in bumblebees, with a faster proboscis retraction. Our results suggest that regulation of toxin intake is not as well-established and effective as the regulation of nutrient intake in bees. Bees are therefore not equally adapted to all specialized pollen metabolites that they can come into contact with.
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5
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Agerbirk N, Hansen CC, Kiefer C, Hauser TP, Ørgaard M, Asmussen Lange CB, Cipollini D, Koch MA. Comparison of glucosinolate diversity in the crucifer tribe Cardamineae and the remaining order Brassicales highlights repetitive evolutionary loss and gain of biosynthetic steps. PHYTOCHEMISTRY 2021; 185:112668. [PMID: 33743499 DOI: 10.1016/j.phytochem.2021.112668] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 01/05/2021] [Accepted: 01/09/2021] [Indexed: 06/12/2023]
Abstract
We review glucosinolate (GSL) diversity and analyze phylogeny in the crucifer tribe Cardamineae as well as selected species from Brassicaceae (tribe Brassiceae) and Resedaceae. Some GSLs occur widely, while there is a scattered distribution of many less common GSLs, tentatively sorted into three classes: ancient, intermediate and more recently evolved. The number of conclusively identified GSLs in the tribe (53 GSLs) constitute 60% of all GSLs known with certainty from any plant (89 GSLs) and apparently unique GSLs in the tribe constitute 10 of those GSLs conclusively identified (19%). Intraspecific, qualitative GSL polymorphism is known from at least four species in the tribe. The most ancient GSL biosynthesis in Brassicales probably involved biosynthesis from Phe, Val, Leu, Ile and possibly Trp, and hydroxylation at the β-position. From a broad comparison of families in Brassicales and tribes in Brassicaceae, we estimate that a common ancestor of the tribe Cardamineae and the family Brassicaceae exhibited GSL biosynthesis from Phe, Val, Ile, Leu, possibly Tyr, Trp and homoPhe (ancient GSLs), as well as homologs of Met and possibly homoIle (intermediate age GSLs). From the comparison of phylogeny and GSL diversity, we also suggest that hydroxylation and subsequent methylation of indole GSLs and usual modifications of Met-derived GSLs (formation of sulfinyls, sulfonyls and alkenyls) occur due to conserved biochemical mechanisms and was present in a common ancestor of the family. Apparent loss of homologs of Met as biosynthetic precursors was deduced in the entire genus Barbarea and was frequent in Cardamine (e.g. C. pratensis, C. diphylla, C. concatenata, possibly C. amara). The loss was often associated with appearance of significant levels of unique or rare GSLs as well as recapitulation of ancient types of GSLs. Biosynthetic traits interpreted as de novo evolution included hydroxylation at rare positions, acylation at the thioglucose and use of dihomoIle and possibly homoIle as biosynthetic precursors. Biochemical aspects of the deduced evolution are discussed and testable hypotheses proposed. Biosyntheses from Val, Leu, Ile, Phe, Trp, homoPhe and homologs of Met are increasingly well understood, while GSL biosynthesis from mono- and dihomoIle is poorly understood. Overall, interpretation of known diversity suggests that evolution of GSL biosynthesis often seems to recapitulate ancient biosynthesis. In contrast, unprecedented GSL biosynthetic innovation seems to be rare.
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Affiliation(s)
- Niels Agerbirk
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark.
| | - Cecilie Cetti Hansen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Christiane Kiefer
- Department of Biodiversity and Plant Systematics, Centre for Organismal Studies, Heidelberg University, 69120, Heidelberg, Germany
| | - Thure P Hauser
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Marian Ørgaard
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Conny Bruun Asmussen Lange
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Don Cipollini
- Department of Biological Sciences, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH, 45435, USA
| | - Marcus A Koch
- Department of Biodiversity and Plant Systematics, Centre for Organismal Studies, Heidelberg University, 69120, Heidelberg, Germany
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6
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Glucosinolate Biosynthesis and the Glucosinolate–Myrosinase System in Plant Defense. AGRONOMY-BASEL 2020. [DOI: 10.3390/agronomy10111786] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Insect pests represent a major global challenge to important agricultural crops. Insecticides are often applied to combat such pests, but their use has caused additional challenges such as environmental contamination and human health issues. Over millions of years, plants have evolved natural defense mechanisms to overcome insect pests and pathogens. One such mechanism is the production of natural repellents or specialized metabolites like glucosinolates. There are three types of glucosinolates produced in the order Brassicales: aliphatic, indole, and benzenic glucosinolates. Upon insect herbivory, a “mustard oil bomb” consisting of glucosinolates and their hydrolyzing enzymes (myrosinases) is triggered to release toxic degradation products that act as insect deterrents. This review aims to provide a comprehensive summary of glucosinolate biosynthesis, the “mustard oil bomb”, and how these metabolites function in plant defense against pathogens and insects. Understanding these defense mechanisms will not only allow us to harness the benefits of this group of natural metabolites for enhancing pest control in Brassicales crops but also to transfer the “mustard oil bomb” to non-glucosinolate producing crops to boost their defense and thereby reduce the use of chemical pesticides.
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7
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Humphrey PT, Whiteman NK. Insect herbivory reshapes a native leaf microbiome. Nat Ecol Evol 2020; 4:221-229. [PMID: 31988447 DOI: 10.1038/s41559-019-1085-x] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Accepted: 12/12/2019] [Indexed: 12/22/2022]
Abstract
Insect herbivory is pervasive in plant communities, but its impact on microbial plant colonizers is not well-studied in natural systems. By calibrating sequencing-based bacterial detection to absolute bacterial load, we find that the within-host abundance of most leaf microbiome (phyllosphere) taxa colonizing a native forb is amplified within leaves affected by insect herbivory. Herbivore-associated bacterial amplification reflects community-wide compositional shifts towards lower ecological diversity, but the extent and direction of such compositional shifts can be interpreted only by quantifying absolute abundance. Experimentally eliciting anti-herbivore defences reshaped within-host fitness ranks among Pseudomonas spp. field isolates and amplified a subset of putatively phytopathogenic P. syringae in a manner causally consistent with observed field-scale patterns. Herbivore damage was inversely correlated with plant reproductive success and was highly clustered across plants, which predicts tight co-clustering with putative phytopathogens across hosts. Insect herbivory may thus drive the epidemiology of plant-infecting bacteria as well as the structure of a native plant microbiome by generating variation in within-host bacterial fitness at multiple phylogenetic and spatial scales. This study emphasizes that 'non-focal' biotic interactions between hosts and other organisms in their ecological settings can be crucial drivers of the population and community dynamics of host-associated microbiomes.
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Affiliation(s)
- Parris T Humphrey
- Organismic & Evolutionary Biology, Harvard University, Cambridge, MA, USA. .,Rocky Mountain Biological Laboratory, Crested Butte, CO, USA. .,Ecology & Evolutionary Biology, University of Arizona, Tucson, AZ, USA.
| | - Noah K Whiteman
- Rocky Mountain Biological Laboratory, Crested Butte, CO, USA.,Ecology & Evolutionary Biology, University of Arizona, Tucson, AZ, USA.,Integrative Biology, University of California, Berkeley, CA, USA
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8
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Beran F, Sporer T, Paetz C, Ahn SJ, Betzin F, Kunert G, Shekhov A, Vassão DG, Bartram S, Lorenz S, Reichelt M. One Pathway Is Not Enough: The Cabbage Stem Flea Beetle Psylliodes chrysocephala Uses Multiple Strategies to Overcome the Glucosinolate-Myrosinase Defense in Its Host Plants. FRONTIERS IN PLANT SCIENCE 2018; 9:1754. [PMID: 30581445 PMCID: PMC6292997 DOI: 10.3389/fpls.2018.01754] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 11/12/2018] [Indexed: 05/18/2023]
Abstract
The cabbage stem flea beetle (Psylliodes chrysocephala) is a key pest of oilseed rape in Europe, and is specialized to feed on Brassicaceae plants armed with the glucosinolate-myrosinase defense system. Upon tissue damage, the β-thioglucosidase enzyme myrosinase hydrolyzes glucosinolates (GLS) to form toxic isothiocyanates (ITCs) which deter non-adapted herbivores. Here, we show that P. chrysocephala selectively sequester GLS from their host plants and store these throughout their life cycle. In addition, P. chrysocephala metabolize GLS to desulfo-GLS, which implies the evolution of GLS sulfatase activity in this specialist. To assess whether P. chrysocephala can largely prevent GLS hydrolysis in ingested plant tissue by sequestration and desulfation, we analyzed the metabolic fate of 4-methylsulfinylbutyl (4MSOB) GLS in adults. Surprisingly, intact and desulfo-GLS together accounted for the metabolic fate of only 26% of the total ingested GLS in P. chrysocephala, indicating that most ingested GLS are nevertheless activated by the plant myrosinase. The presence of 4MSOB-ITC and the corresponding nitrile in feces extracts confirmed the activation of ingested GLS, but the detected amounts of unmetabolized ITCs were low. P. chrysocephala partially detoxifies ITCs by conjugation with glutathione via the conserved mercapturic acid pathway. In addition to known products of the mercapturic acid pathway, we identified two previously unknown cyclic metabolites derived from the cysteine-conjugate of 4MSOB-ITC. In summary, the cabbage stem flea beetle avoids ITC formation by specialized strategies, but also relies on and extends the conserved mercapturic acid pathway to prevent toxicity of formed ITCs.
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Affiliation(s)
- Franziska Beran
- Research Group Sequestration and Detoxification in Insects, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Theresa Sporer
- Research Group Sequestration and Detoxification in Insects, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Christian Paetz
- Research Group Biosynthesis/NMR, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Seung-Joon Ahn
- Research Group Sequestration and Detoxification in Insects, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Franziska Betzin
- Research Group Sequestration and Detoxification in Insects, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Grit Kunert
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Anton Shekhov
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Daniel G. Vassão
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Stefan Bartram
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Sybille Lorenz
- Research Group Mass Spectrometry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Michael Reichelt
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
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9
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Alexandre NM, Humphrey PT, Gloss AD, Lee J, Frazier J, Affeldt HA, Whiteman NK. Habitat preference of an herbivore shapes the habitat distribution of its host plant. Ecosphere 2018; 9. [PMID: 30828480 DOI: 10.1002/ecs2.2372] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Plant distributions can be limited by habitat-biased herbivory, but the proximate causes of such biases are rarely known. Distinguishing plant-centric from herbivore-centric mechanisms driving differential herbivory between habitats is difficult without experimental manipulation of both plants and herbivores. Here we tested alternative hypotheses driving habitat-biased herbivory in bittercress (Cardamine cordifolia), which is more abundant under shade of shrubs and trees (shade) than in nearby meadows (sun) where herbivory is intense from the specialist fly Scaptomyza nigrita. This system has served as a textbook example of habitat-biased herbivory driving a plant's distribution across an ecotone, but the proximate mechanisms underlying differential herbivory are still unclear. First, we found that higher S. nigrita herbivory in sun habitats contrasts sharply with their preference to attack plants from shade habitats in laboratory choice experiments. Second, S. nigrita strongly preferred leaves in simulated sun over simulated shade habitats, regardless of plant source habitat. Thus, herbivore preference for brighter, warmer habitats overrides their preference for more palatable shade plants. This promotes the sun-biased herbivore pressure that drives the distribution of bittercress into shade habitats.
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Affiliation(s)
- Nicolas M Alexandre
- Department of Integrative Biology, University of California, Berkeley, California 94720 USA.,Rocky Mountain Biological Laboratory, Crested Butte, Colorado 81224 USA.,Department of Ecology & Evolutionary Biology, University of Arizona, Tucson, Arizona 85721 USA
| | - Parris T Humphrey
- Rocky Mountain Biological Laboratory, Crested Butte, Colorado 81224 USA.,Department of Ecology & Evolutionary Biology, University of Arizona, Tucson, Arizona 85721 USA.,Department of Organismic & Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138 USA
| | - Andrew D Gloss
- Rocky Mountain Biological Laboratory, Crested Butte, Colorado 81224 USA.,Department of Ecology & Evolutionary Biology, University of Arizona, Tucson, Arizona 85721 USA.,Department of Ecology & Evolution, University of Chicago, Chicago, Illinois 60637 USA
| | - Jimmy Lee
- Rocky Mountain Biological Laboratory, Crested Butte, Colorado 81224 USA
| | - Joseph Frazier
- Rocky Mountain Biological Laboratory, Crested Butte, Colorado 81224 USA
| | - Henry A Affeldt
- Rocky Mountain Biological Laboratory, Crested Butte, Colorado 81224 USA
| | - Noah K Whiteman
- Department of Integrative Biology, University of California, Berkeley, California 94720 USA.,Rocky Mountain Biological Laboratory, Crested Butte, Colorado 81224 USA.,Department of Ecology & Evolutionary Biology, University of Arizona, Tucson, Arizona 85721 USA
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10
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Humphrey PT, Gloss AD, Frazier J, Nelson-Dittrich AC, Faries S, Whiteman NK. Heritable plant phenotypes track light and herbivory levels at fine spatial scales. Oecologia 2018; 187:427-445. [PMID: 29603095 PMCID: PMC5999565 DOI: 10.1007/s00442-018-4116-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 03/11/2018] [Indexed: 02/03/2023]
Abstract
Organismal phenotypes often co-vary with environmental variables across broad geographic ranges. Less is known about the extent to which phenotypes match local conditions when multiple biotic and abiotic stressors vary at fine spatial scales. Bittercress (Brassicaceae: Cardamine cordifolia), a perennial forb, grows across a microgeographic mosaic of two contrasting herbivory regimes: high herbivory in meadows (sun habitats) and low herbivory in deeply shaded forest understories (shade habitats). We tested for local phenotypic differentiation in plant size, leaf morphology, and anti-herbivore defense (realized resistance and defensive chemicals, i.e., glucosinolates) across this habitat mosaic through reciprocal transplant-common garden experiments with clonally propagated rhizomes. We found habitat-specific divergence in morphological and defensive phenotypes that manifested as contrasting responses to growth in shade common gardens: weak petiole elongation and attenuated defenses in populations from shade habitats, and strong petiole elongation and elevated defenses in populations from sun habitats. These divergent phenotypes are generally consistent with reciprocal local adaptation: plants from shade habitats that naturally experience low herbivory show reduced investment in defense and an attenuated shade avoidance response, owing to its ineffectiveness within forest understories. By contrast, plants from sun habitats with high herbivory show shade-induced elongation, but no evidence of attenuated defenses canonically associated with elongation in shade-intolerant plant species. Finally, we observed differences in flowering phenology between habitat types that could potentially contribute to inter-habitat divergence by reducing gene flow. This study illuminates how clonally heritable plant phenotypes track a fine-grained mosaic of herbivore pressure and light availability in a native plant.
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Affiliation(s)
- P T Humphrey
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721, USA
- Rocky Mountain Biological Laboratory, Gothic, CO, 81224, USA
| | - A D Gloss
- Department of Ecology and Evolution, University of Chicago, Chicago, IL, USA
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721, USA
- Rocky Mountain Biological Laboratory, Gothic, CO, 81224, USA
| | - J Frazier
- Rocky Mountain Biological Laboratory, Gothic, CO, 81224, USA
| | - A C Nelson-Dittrich
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, 85721, USA
| | - S Faries
- Rocky Mountain Biological Laboratory, Gothic, CO, 81224, USA
| | - N K Whiteman
- Rocky Mountain Biological Laboratory, Gothic, CO, 81224, USA.
- Department of Integrative Biology, University of California, Berkeley, CA, 91645, USA.
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11
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Olsen CE, Huang XC, Hansen CIC, Cipollini D, Ørgaard M, Matthes A, Geu-Flores F, Koch MA, Agerbirk N. Glucosinolate diversity within a phylogenetic framework of the tribe Cardamineae (Brassicaceae) unraveled with HPLC-MS/MS and NMR-based analytical distinction of 70 desulfoglucosinolates. PHYTOCHEMISTRY 2016; 132:33-56. [PMID: 27743600 DOI: 10.1016/j.phytochem.2016.09.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 08/29/2016] [Accepted: 09/29/2016] [Indexed: 05/22/2023]
Abstract
As a basis for future investigations of evolutionary trajectories and biosynthetic mechanisms underlying variations in glucosinolate structures, we screened members of the crucifer tribe Cardamineae by HPLC-MS/MS, isolated and identified glucosinolates by NMR, searched the literature for previous data for the tribe, and collected HPLC-MS/MS data for nearly all glucosinolates known from the tribe as well as some related structures (70 in total). This is a considerable proportion of the approximately 142 currently documented natural glucosinolates. Calibration with authentic references allowed distinction (or elucidation) of isomers in many cases, such as distinction of β-hydroxyls, methylthios, methylsulfinyls and methylsulfonyls. A mechanism for fragmentation of secondary β-hydroxyls in MS was elucidated, and two novel glucosinolates were discovered: 2-hydroxy-3-methylpentylglucosinolate in roots of Cardamine pratensis and 2-hydroxy-8-(methylsulfinyl)octylglucosinolate in seeds of Rorippa amphibia. A large number of glucosinolates (ca. 54 with high structural certainty and a further 28 or more suggested from tandem MS), representing a wide structural variation, is documented from the tribe. This included glucosinolates apparently derived from Met, Phe, Trp, Val/Leu, Ile and higher homologues. Normal side chain elongation and side chain decoration by oxidation or methylation was observed, as well as rare abnormal side chain decoration (hydroxylation of aliphatics at the δ rather than β-position). Some species had diverse profiles, e.g. R. amphibia and C. pratensis (19 and 16 individual glucosinolates, respectively), comparable to total diversity in literature reports of Armoracia rusticana (17?), Barbarea vulgaris (20-24), and Rorippa indica (>20?). The ancestor or the tribe would appear to have used Trp, Met, and homoPhe as glucosinolate precursor amino acids, and to exhibit oxidation of thio to sulfinyl, formation of alkenyls, β-hydroxylation of aliphatic chains and hydroxylation and methylation of indole glucosinolates. Two hotspots of apparent biochemical innovation and loss were identified: C. pratensis and the genus Barbarea. Diversity in other species mainly included structures also known from other crucifers. In addition to a role of gene duplication, two contrasting genetic/biochemical mechanisms for evolution of such combined diversity and redundancy are discussed: (i) involvement of widespread genes with expression varying during evolution, and (ii) mutational changes in substrate specificities of CYP79F and GS-OH enzymes.
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Affiliation(s)
- Carl Erik Olsen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Xiao-Chen Huang
- Biodiversity and Plant Systematics, Centre for Organismal Studies (COS) Heidelberg, Heidelberg University, Im Neuenheimer Feld 345, 69120 Heidelberg, Germany
| | - Cecilie I C Hansen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Don Cipollini
- Department of Biological Sciences, Wright State University, 3640 Colonel Glenn Highway, Dayton, OH 45435, USA
| | - Marian Ørgaard
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Annemarie Matthes
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark; Copenhagen Plant Science Center, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Fernando Geu-Flores
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark; Copenhagen Plant Science Center, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Marcus A Koch
- Biodiversity and Plant Systematics, Centre for Organismal Studies (COS) Heidelberg, Heidelberg University, Im Neuenheimer Feld 345, 69120 Heidelberg, Germany
| | - Niels Agerbirk
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark; Copenhagen Plant Science Center, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark.
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