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Kariñho Betancourt E, Calderón Cortés N, Tapia López R, De-la-Cruz I, Núñez Farfán J, Oyama K. Comparative transcriptome profiling reveals distinct regulatory responses of secondary defensive metabolism in Datura species (Solanaceae) under plant development and herbivory-mediated stress. Ecol Evol 2024; 14:e11496. [PMID: 38983703 PMCID: PMC11231941 DOI: 10.1002/ece3.11496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 05/14/2024] [Accepted: 05/15/2024] [Indexed: 07/11/2024] Open
Abstract
Differential expression of genes is key to mediating developmental and stress-related plant responses. Here, we addressed the regulation of plant metabolic responses to biotic stress and the developmental variation of defense-related genes in four species of the genus Datura with variable patterns of metabolite accumulation and development. We combine transcriptome profiling with phylogenomic techniques to analyze gene expression and coexpression in plants subjected to damage by a specialist folivore insect. We found (1) common overall gene expression in species of similar chemical profiles, (2) species-specific responses of proteins involved in specialized metabolism, characterized by constant levels of gene expression coupled with transcriptional rearrangement, and (3) induction of transcriptional rearrangement of major terpene and tropane alkaloid genes upon herbivory. Our results indicate differential modulation of terpene and tropane metabolism linked to jasmonate signaling and specific transcription factors to regulate developmental variation and stress programs, and suggest plastic adaptive responses to cope with herbivory. The transcriptional profiles of specialized metabolism shown here reveal complex genetic control of plant metabolism and contribute to understanding the molecular basis of adaptations and the physiological variation of significant ecological traits.
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Affiliation(s)
- Eunice Kariñho Betancourt
- Escuela Nacional de Estudios Superiores (ENES) Unidad Morelia, UNAM Morelia Mexico
- Laboratorio de Genética Ecológica y Evolución Instituto de Ecología, UNAM Ciudad de México Mexico
| | | | - Rosalinda Tapia López
- Laboratorio de Evolución Molecular y Experimental Instituto de Ecología, UNAM Ciudad de México Mexico
| | - Ivan De-la-Cruz
- Department of Plant Protection Biology Swedish University of Agricultural Sciences Alnarp Sweden
| | - Juan Núñez Farfán
- Laboratorio de Genética Ecológica y Evolución Instituto de Ecología, UNAM Ciudad de México Mexico
| | - Ken Oyama
- Escuela Nacional de Estudios Superiores (ENES) Unidad Morelia, UNAM Morelia Mexico
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Somers DJ, Kushner DB, McKinnis AR, Mehmedovic D, Flame RS, Arnold TM. Epigenetic weapons in plant-herbivore interactions: Sulforaphane disrupts histone deacetylases, gene expression, and larval development in Spodoptera exigua while the specialist feeder Trichoplusia ni is largely resistant to these effects. PLoS One 2023; 18:e0293075. [PMID: 37856454 PMCID: PMC10586618 DOI: 10.1371/journal.pone.0293075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 10/03/2023] [Indexed: 10/21/2023] Open
Abstract
Cruciferous plants produce sulforaphane (SFN), an inhibitor of nuclear histone deacetylases (HDACs). In humans and other mammals, the consumption of SFN alters enzyme activities, DNA-histone binding, and gene expression within minutes. However, the ability of SFN to act as an HDAC inhibitor in nature, disrupting the epigenetic machinery of insects feeding on these plants, has not been explored. Here, we demonstrate that SFN consumed in the diet inhibits the activity of HDAC enzymes and slows the development of the generalist grazer Spodoptera exigua, in a dose-dependent fashion. After consuming SFN for seven days, the activities of HDAC enzymes in S. exigua were reduced by 50%. Similarly, larval mass was reduced by 50% and pupation was delayed by 2-5 days, with no additional mortality. Similar results were obtained when SFN was applied topically to eggs. RNA-seq analyses confirm that SFN altered the expression of thousands of genes in S. exigua. Genes associated with energy conversion pathways were significantly downregulated while those encoding for ribosomal proteins were dramatically upregulated in response to the consumption of SFN. In contrast, the co-evolved specialist feeder Trichoplusia ni was not negatively impacted by SFN, whether it was consumed in their diet at natural concentrations or applied topically to eggs. The activities of HDAC enzymes were not inhibited and development was not disrupted. In fact, SFN exposure sometimes accelerated T. ni development. RNA-seq analyses revealed that the consumption of SFN alters gene expression in T. ni in similar ways, but to a lesser degree, compared to S. exigua. This apparent resistance of T. ni can be overwhelmed by unnaturally high levels of SFN or by exposure to more powerful pharmaceutical HDAC inhibitors. These results demonstrate that dietary SFN interferes with the epigenetic machinery of insects, supporting the hypothesis that plant-derived HDAC inhibitors serve as "epigenetic weapons" against herbivores.
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Affiliation(s)
- Dana J. Somers
- Department of Biology, Program in Biochemistry and Molecular Biology, Dickinson College, Carlisle, PA United States of America
| | - David B. Kushner
- Department of Biology, Program in Biochemistry and Molecular Biology, Dickinson College, Carlisle, PA United States of America
| | - Alexandria R. McKinnis
- Department of Biology, Program in Biochemistry and Molecular Biology, Dickinson College, Carlisle, PA United States of America
| | - Dzejlana Mehmedovic
- Department of Biology, Program in Biochemistry and Molecular Biology, Dickinson College, Carlisle, PA United States of America
| | - Rachel S. Flame
- Department of Biology, Program in Biochemistry and Molecular Biology, Dickinson College, Carlisle, PA United States of America
| | - Thomas M. Arnold
- Department of Biology, Program in Biochemistry and Molecular Biology, Dickinson College, Carlisle, PA United States of America
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Valle D, Mujica V, Gonzalez A. Herbivore-Dependent Induced Volatiles in Pear Plants Cause Differential Attractive Response by Lacewing Larvae. J Chem Ecol 2023; 49:262-275. [PMID: 36690765 DOI: 10.1007/s10886-023-01403-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/04/2023] [Accepted: 01/10/2023] [Indexed: 01/25/2023]
Abstract
Biological control may benefit from the behavioral manipulation of natural enemies using volatile organic compounds (VOCs). Among these, herbivore-induced plant volatiles (HIPVs) provide potential tools for attracting or retaining predators and parasitoids of insect pests. This work aimed to characterize the VOCs emitted by pear plants in response to attack by Cacopsylla bidens (Hemiptera: Psyllidae), a major pest in pear orchards, to compare these with VOCs induced by a leaf chewing insect, Argyrotaenia sphaleropa (Lepidoptera: Tortricidae), and to evaluate the behavioral response of Chrysoperla externa (Neuroptera: Chrysopidae) to HIPVs from pear plants damaged by either herbivore. The results demonstrated that plants damaged by the pear psylla emitted VOC blends with increased amounts of aliphatic aldehydes. Leafroller damage resulted in increased amounts of benzeneacetonitrile, (E)-4,8-dimethylnona-1,3,7-triene, β-ocimene and caryophyllene. In olfactometer bioassays, larvae of C. externa were attracted to herbivore-damaged plants when contrasted with undamaged plants. When plant odors from psylla-damaged were contrasted with those of leafroller-damaged plants, C.externa preferred the former, also showing shorter response lag-times and higher response rates when psylla-damaged plants were present. Our results suggest that pear plants respond to herbivory by modifying their volatile profile, and that psylla-induced volatiles may be used as prey-specific chemical cues by chrysopid larvae. Our study is the first to report HIPVs in pear plants attacked by C. bidens, as well as the attraction of C. externa to psyllid-induced volatiles.
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Affiliation(s)
- D Valle
- Protección Vegetal, Instituto Nacional de Investigación Agropecuaria, INIA Las Brujas, Canelones, Uruguay.
| | - V Mujica
- Protección Vegetal, Instituto Nacional de Investigación Agropecuaria, INIA Las Brujas, Canelones, Uruguay
| | - A Gonzalez
- Laboratorio de Ecología Química, Facultad de Química, Universidad de la República, Montevideo, Uruguay
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Puri H, Ikuze E, Ayala J, Rodriguez I, Kariyat R, Louis J, Grover S. Greenbug feeding-induced resistance to sugarcane aphids in sorghum. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.1105725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
Plants are attacked by multiple insect pest species and insect herbivory can alter plant defense mechanisms. The plant defense responses to a specific herbivore may also contribute to the herbivore growth/survival on plants. Feeding by one insect species can modulate the plant defenses, which can either facilitate or hamper the colonization of subsequent incoming insects. However, little is known about the effect of sequential herbivory on sorghum plants. In this study, we demonstrate that a specialist aphid, sugarcane aphid (SCA; Melanaphis sacchari) grows faster on sorghum than a generalist aphid species, greenbug (GB; Schizaphis graminum). We also determined how the pre-infestation of SCA on sorghum affected the invasion of GB and vice-versa. Our sequential herbivory experiments revealed that SCA reproduction was lower on GB-primed sorghum plants, however, the reverse was not true. To assess the differences in plant defenses induced by specialist vs. generalist aphids, we monitored the expression of salicylic acid (SA) and jasmonic acid (JA) marker genes, and flavonoid biosynthetic pathway genes after 48 h of aphid infestation. The results indicated that GB infestation induced higher expression of SA and JA-related genes, and flavonoid pathway genes (DFR, FNR, and FNSII) compared to SCA infestation. Overall, our results suggested that GB-infested plants activate the plant defenses via phytohormones and flavonoids at early time points and hampers the colonization of incoming SCA, as well as explain the reproductive success of SCA compared to GB.
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Rusman Q, Hooiveld‐Knoppers S, Dijksterhuis M, Bloem J, Reichelt M, Dicke M, Poelman EH. Flowers prepare thyselves: leaf and root herbivores induce specific changes in floral phytochemistry with consequences for plant interactions with florivores. THE NEW PHYTOLOGIST 2022; 233:2548-2560. [PMID: 34953172 PMCID: PMC9305281 DOI: 10.1111/nph.17931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 12/06/2021] [Indexed: 06/14/2023]
Abstract
The phenotypic plasticity of flowering plants in response to herbivore damage to vegetative tissues can affect plant interactions with flower-feeding organisms. Such induced systemic responses are probably regulated by defence-related phytohormones that signal flowers to alter secondary chemistry that affects resistance to florivores. Current knowledge on the effects of damage to vegetative tissues on plant interactions with florivores and the underlying mechanisms is limited. We compared the preference and performance of two florivores on flowering Brassica nigra plants damaged by one of three herbivores feeding from roots or leaves. To investigate the underlying mechanisms, we quantified expression patterns of marker genes for defence-related phytohormonal pathways, and concentrations of phytohormones and glucosinolates in buds and flowers. Florivores displayed contrasting preferences for plants damaged by herbivores feeding on roots and leaves. Chewing florivores performed better on plants damaged by folivores, but worse on plants damaged by the root herbivore. Chewing root and foliar herbivory led to specific induced changes in the phytohormone profile of buds and flowers. This resulted in increased glucosinolate concentrations for leaf-damaged plants, and decreased glucosinolate concentrations for root-damaged plants. The outcome of herbivore-herbivore interactions spanning from vegetative tissues to floral tissues is unique for the inducing root/leaf herbivore and receiving florivore combination.
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Affiliation(s)
- Quint Rusman
- Laboratory of EntomologyWageningen University & ResearchDroevendaalsesteeg 1Wageningen6708PBthe Netherlands
- Present address:
Department of Systematic and Evolutionary BotanyUniversity of ZürichZollikerstrasse 1078008ZürichSwitzerland
| | - Sanne Hooiveld‐Knoppers
- Laboratory of EntomologyWageningen University & ResearchDroevendaalsesteeg 1Wageningen6708PBthe Netherlands
| | - Mirjam Dijksterhuis
- Laboratory of EntomologyWageningen University & ResearchDroevendaalsesteeg 1Wageningen6708PBthe Netherlands
| | - Janneke Bloem
- Laboratory of EntomologyWageningen University & ResearchDroevendaalsesteeg 1Wageningen6708PBthe Netherlands
| | - Michael Reichelt
- Department of BiochemistryMax Planck Institute for Chemical EcologyHans‐Knöll‐Strasse 807745JenaGermany
| | - Marcel Dicke
- Laboratory of EntomologyWageningen University & ResearchDroevendaalsesteeg 1Wageningen6708PBthe Netherlands
| | - Erik H. Poelman
- Laboratory of EntomologyWageningen University & ResearchDroevendaalsesteeg 1Wageningen6708PBthe Netherlands
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Karssemeijer PN, Winzen L, van Loon JJA, Dicke M. Leaf-chewing herbivores affect preference and performance of a specialist root herbivore. Oecologia 2022; 199:243-255. [PMID: 35192063 PMCID: PMC9226102 DOI: 10.1007/s00442-022-05132-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 02/04/2022] [Indexed: 11/27/2022]
Abstract
Plants interact with a diversity of phytophagous insects above- and belowground. By inducing plant defence, one insect herbivore species can antagonize or facilitate other herbivore species feeding on the same plant, even when they are separated in space and time. Through systemic plant-mediated interactions, leaf-chewing herbivores may affect the preference and performance of root-feeding herbivores. We studied how six different leaf-chewing herbivore species of Brassica oleracea plants affected oviposition preference and larval performance of the root-feeding specialist Delia radicum. We expected that female D. radicum flies would oviposit where larval performance was highest, in accordance with the preference–performance hypothesis. We also assessed how the different leaf-chewing herbivore species affected defence-related gene expression in leaves and primary roots of B. oleracea, both before and after infestation with the root herbivore. Our results show that leaf-chewing herbivores can negatively affect the performance of root-feeding D. radicum larvae, although the effects were relatively weak. Surprisingly, we found that adult D. radicum females show a strong preference to oviposit on plants infested with a leaf-chewing herbivore. Defence-related genes in primary roots of B. oleracea plants were affected by the leaf-chewing herbivores, but these changes were largely overridden upon local induction by D. radicum. Infestation by leaf herbivores makes plants more attractive for oviposition by D. radicum females, while decreasing larval performance. Therefore, our findings challenge the preference–performance hypothesis in situations where other herbivore species are present.
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Affiliation(s)
- Peter N Karssemeijer
- Laboratory of Entomology, Wageningen University and Research, Wageningen, The Netherlands.
| | - Laura Winzen
- Laboratory of Entomology, Wageningen University and Research, Wageningen, The Netherlands
| | - Joop J A van Loon
- Laboratory of Entomology, Wageningen University and Research, Wageningen, The Netherlands
| | - Marcel Dicke
- Laboratory of Entomology, Wageningen University and Research, Wageningen, The Netherlands
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7
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Mertens D, Fernández de Bobadilla M, Rusman Q, Bloem J, Douma JC, Poelman EH. Plant defence to sequential attack is adapted to prevalent herbivores. NATURE PLANTS 2021; 7:1347-1353. [PMID: 34650263 DOI: 10.1038/s41477-021-00999-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 08/02/2021] [Indexed: 05/21/2023]
Abstract
Plants have evolved plastic defence strategies to deal with the uncertainty of when, by which species and in which order attack by herbivores will take place1-3. However, the responses to current herbivore attack may come with a cost of compromising resistance to other, later arriving herbivores. Due to antagonistic cross-talk between physiological regulation of plant resistance to phloem-feeding and leaf-chewing herbivores4-8, the feeding guild of the initial herbivore is considered to be the primary factor determining whether resistance to subsequent attack is compromised. We show that, by investigating 90 pairwise insect-herbivore interactions among ten different herbivore species, resistance of the annual plant Brassica nigra to a later arriving herbivore species is not explained by feeding guild of the initial attacker. Instead, the prevalence of herbivore species that arrive on induced plants as approximated by three years of season-long insect community assessments in the field explained cross-resistance. Plants maintained resistance to prevalent herbivores in common patterns of herbivore arrival and compromises in resistance especially occurred for rare patterns of herbivore attack. We conclude that plants tailor induced defence strategies to deal with common patterns of sequential herbivore attack and anticipate arrival of the most prevalent herbivores.
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Affiliation(s)
- Daan Mertens
- Laboratory of Entomology, Wageningen University, Wageningen, the Netherlands
| | | | - Quint Rusman
- Laboratory of Entomology, Wageningen University, Wageningen, the Netherlands
| | - Janneke Bloem
- Laboratory of Entomology, Wageningen University, Wageningen, the Netherlands
| | - Jacob C Douma
- Centre for Crop Systems Analysis, Wageningen University, Wageningen, the Netherlands
| | - Erik H Poelman
- Laboratory of Entomology, Wageningen University, Wageningen, the Netherlands.
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8
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Wallis CM, Galarneau ERA. Phenolic Compound Induction in Plant-Microbe and Plant-Insect Interactions: A Meta-Analysis. FRONTIERS IN PLANT SCIENCE 2020; 11:580753. [PMID: 33384701 PMCID: PMC7769804 DOI: 10.3389/fpls.2020.580753] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 11/24/2020] [Indexed: 05/15/2023]
Abstract
Plants rely on a variety of ways to protect themselves from being fed upon, including de novo production of specific compounds such as those termed as phenolics. Phenolics are often described as important in plant health and numerous studies have concluded they increase as a result of insect feeding, pathogen infection, or beneficial microorganism colonization. However, there are some studies reaching differing conclusions. Therefore, meta-analyses were conducted to observe whether common trends in phenolic induction in plants can be made when they become hosts to insects or microorganisms. Four hypotheses were tested. The first was that total phenolics increase as a generic response, and meta-analyses confirmed that this occurs when plants are infested with insects or colonized by bacterial or fungal microorganisms, but not for oomycetes. The second hypothesis was that phenolic induction is different when a beneficial microorganism colonizes a plant vs. when a plant is infected by a pathogen. Beneficial bacteria, pathogenic bacteria, and beneficial fungi produced increased phenolic levels in plant hosts, but fungal pathogens did not. The third hypothesis was that insect feeding method on plant hosts determines if phenolics are induced. Chewing induced phenolics but piercing-sucking and wood-boring did not. Lastly, we used meta-analyses to determine if annual or perennials rely on phenolic induction in different amounts, and even though annuals had significantly increased phenolic levels but perennials did not, it was observed that phenolic induction was not statistically different when plant type was considered. These results demonstrate that phenolic induction is a common response in plant hosts exposed to feeding or colonization, with specific exceptions such a pathogenic fungi and piercing-sucking insects.
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Affiliation(s)
- Christopher M. Wallis
- Crop Diseases Pest and Genetics Research Unit, USDA-ARS San Joaquin Valley Agricultural Sciences Center, Parlier, CA, United States
- *Correspondence: Christopher M. Wallis
| | - Erin R.-A. Galarneau
- Viticulture and Enology Department, University of California, Davis, Davis, CA, United States
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Sontowski R, Gorringe NJ, Pencs S, Schedl A, Touw AJ, van Dam NM. Same Difference? Low and High Glucosinolate Brassica rapa Varieties Show Similar Responses Upon Feeding by Two Specialist Root Herbivores. FRONTIERS IN PLANT SCIENCE 2019; 10:1451. [PMID: 31798608 PMCID: PMC6865846 DOI: 10.3389/fpls.2019.01451] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 10/17/2019] [Indexed: 06/10/2023]
Abstract
Glucosinolates (GSLs) evolved in Brassicaceae as chemical defenses against herbivores. The GSL content in plants is affected by both abiotic and biotic factors, but also depends on the genetic background of the plant. Since the bitter taste of GSLs can be unfavorable for both livestock and human consumption, several plant varieties with low GSL seed or leaf content have been bred. Due to their lower GSL levels, such varieties can be more susceptible to herbivore pests. However, low GSL varieties may quickly increase GSL levels upon herbivore feeding by activating GSL biosynthesis, hydrolysis, or transporter genes. To analyze differences in herbivore-induced GSL responses in relation to constitutive GSL levels, we selected four Brassica rapa varieties, containing either low or high root GSL levels. Plants were infested either with Delia radicum or Delia floralis larvae. The larvae of both root flies are specialists on Brassica plants. Root samples were collected after 3, 5, and 7 days. We compared the effect of root herbivore damage on the expression of GSL biosynthesis (CYP79A1, CYP83B2), transporter (GTR1A2, GTR2A2), and GSL hydrolysis genes (PEN2, TGG2) in roots of low and high GSL varieties in conjugation with their GSL levels. We found that roots of high GSL varieties contained higher levels of aliphatic, indole, and benzyl GSLs than low GSL varieties. Infestation with D. radicum larvae led to upregulation of indole GSL synthesis genes in low and high GSL varieties. High GSL varieties showed no or later responses than low varieties to D. floralis herbivory. Low GSL varieties additionally upregulated the GSL transporter gene expression. Low GSL varieties did not show a stronger herbivore-induced response than high GSL varieties, which indicates that there is no trade-off between constitutive and induced GSLs.
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Affiliation(s)
- Rebekka Sontowski
- Molecular Interaction Ecology, German Centre for Integrative Biodiversity Research Halle-Jena-Leipzig, Leipzig, Germany
- Institute for Biodiversity, Friedrich Schiller University, Jena, Germany
| | - Nicola J. Gorringe
- Molecular Interaction Ecology, German Centre for Integrative Biodiversity Research Halle-Jena-Leipzig, Leipzig, Germany
- School of Biosciences, Cardiff University, Cardiff, Wales, United Kingdom
| | - Stefanie Pencs
- Molecular Interaction Ecology, German Centre for Integrative Biodiversity Research Halle-Jena-Leipzig, Leipzig, Germany
- Institute for Biodiversity, Friedrich Schiller University, Jena, Germany
| | - Andreas Schedl
- Molecular Interaction Ecology, German Centre for Integrative Biodiversity Research Halle-Jena-Leipzig, Leipzig, Germany
- Institute for Biodiversity, Friedrich Schiller University, Jena, Germany
| | - Axel J. Touw
- Molecular Interaction Ecology, German Centre for Integrative Biodiversity Research Halle-Jena-Leipzig, Leipzig, Germany
- Institute for Biodiversity, Friedrich Schiller University, Jena, Germany
| | - Nicole M. van Dam
- Molecular Interaction Ecology, German Centre for Integrative Biodiversity Research Halle-Jena-Leipzig, Leipzig, Germany
- Institute for Biodiversity, Friedrich Schiller University, Jena, Germany
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Ogran A, Faigenboim A, Barazani O. Transcriptome responses to different herbivores reveal differences in defense strategies between populations of Eruca sativa. BMC Genomics 2019; 20:843. [PMID: 31718552 PMCID: PMC6852892 DOI: 10.1186/s12864-019-6217-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 10/23/2019] [Indexed: 01/01/2023] Open
Abstract
Background Intraspecific variations among induced responses might lead to understanding of adaptive variations in defense strategies against insects. We employed RNA-Seq transcriptome screening to elucidate the molecular basis for phenotypic differences between two populations of Eruca sativa (Brassicaceae), in defense against larvae of the generalist and specialist insects, Spodoptera littoralis and Pieris brassicae, respectively. The E. sativa populations originated from desert and Mediterranean sites, where the plants grow in distinct habitats. Results Responses to elicitation of the plants’ defenses against wounding and insect herbivory resulted in more upregulated transcripts in plants of the Mediterranean population than in those of the desert. PCA analysis differentiated between the two populations and between the elicitation treatments. Comprehensive analysis indicated that defense responses involved induction of the salicylic acid and jasmonic acid pathways in plants of the desert and Mediterranean populations, respectively. In general, the defense response involved upregulation of the aliphatic glucosinolates pathway in plants of the Mediterranean population, whereas herbivory caused downregulation of this pathway in desert plants. Further quantitative RT-PCR analysis indicated that defense response in the desert plants involved higher expression of nitrile-specifier protein (NSP) than in the Mediterranean plants, suggesting that in the desert plants glucosinolates breakdown products are directed to simple-nitriles rather than to the more toxic isothiocyanates. In addition, the defense response in plants of the desert population involved upregulation of flavonoid synthesis and sclerophylly. Conclusions The results indicated that differing defense responses in plants of the two populations are governed by different signaling cascades. We suggest that adaptive ecotypic differentiation in defense strategies could result from generalist and specialist herbivore pressures in the Mediterranean and desert populations, respectively. Moreover, the defense responses in plants of the desert habitat, which include upregulation of mechanical defenses, also could be associated with their dual role in defense against both biotic and abiotic stresses.
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Affiliation(s)
- Ariel Ogran
- Institute of Plant Science, Agricultural Research Organization - the Volcani Center, 7505101, Rishon LeZion, Israel
| | - Adi Faigenboim
- Institute of Plant Science, Agricultural Research Organization - the Volcani Center, 7505101, Rishon LeZion, Israel
| | - Oz Barazani
- Institute of Plant Science, Agricultural Research Organization - the Volcani Center, 7505101, Rishon LeZion, Israel.
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Stam JM, Kos M, Dicke M, Poelman EH. Cross-seasonal legacy effects of arthropod community on plant fitness in perennial plants. THE JOURNAL OF ECOLOGY 2019; 107:2451-2463. [PMID: 31598003 PMCID: PMC6774310 DOI: 10.1111/1365-2745.13231] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 06/06/2019] [Indexed: 05/21/2023]
Abstract
In perennial plants, interactions with other community members during the vegetative growth phase may influence community assembly during subsequent reproductive years and may influence plant fitness. It is well-known that plant responses to herbivory affect community assembly within a growing season, but whether plant-herbivore interactions result in legacy effects on community assembly across seasons has received little attention. Moreover, whether plant-herbivore interactions during the vegetative growing season are important in predicting plant fitness directly or indirectly through legacy effects is poorly understood.Here, we tested whether plant-arthropod interactions in the vegetative growing season of perennial wild cabbage plants, Brassica oleracea, result in legacy effects in arthropod community assembly in the subsequent reproductive season and whether legacy effects have plant fitness consequences. We monitored the arthropod community on plants that had been induced with either aphids, caterpillars or no herbivores in a full-factorial design across 2 years. We quantified the plant traits 'height', 'number of leaves' and 'number of flowers' to understand mechanisms that may mediate legacy effects. We measured seed production in the second year to evaluate plant fitness consequences of legacy effects.Although we did not find community responses to the herbivory treatments, our data show that community composition in the first year leaves a legacy on community composition in a second year: predator community composition co-varied across years. Structural equation modelling analyses indicated that herbivore communities in the vegetative year correlated with plant performance traits that may have caused a legacy effect on especially predator community assembly in the subsequent reproductive year. Interestingly, the legacy of the herbivore community in the vegetative year predicted plant fitness better than the herbivore community that directly interacted with plants in the reproductive year. Synthesis. Thus, legacy effects of plant-herbivore interactions affect community assembly on perennial plants across growth seasons and these processes may affect plant reproductive success. We argue that plant-herbivore interactions in the vegetative phase as well as in the cross-seasonal legacy effects caused by plant responses to arthropod herbivory may be important in perennial plant trait evolution such as ontogenetic variation in growth and defence strategies.
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Affiliation(s)
- Jeltje M. Stam
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
| | - Martine Kos
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
| | - Marcel Dicke
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
| | - Erik H. Poelman
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
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12
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Rusman Q, Poelman EH, Nowrin F, Polder G, Lucas‐Barbosa D. Floral plasticity: Herbivore-species-specific-induced changes in flower traits with contrasting effects on pollinator visitation. PLANT, CELL & ENVIRONMENT 2019; 42:1882-1896. [PMID: 30659631 PMCID: PMC6850075 DOI: 10.1111/pce.13520] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 01/15/2019] [Indexed: 05/20/2023]
Abstract
Plant phenotypic plasticity in response to antagonists can affect other community members such as mutualists, conferring potential ecological costs associated with inducible plant defence. For flowering plants, induction of defences to deal with herbivores can lead to disruption of plant-pollinator interactions. Current knowledge on the full extent of herbivore-induced changes in flower traits is limited, and we know little about specificity of induction of flower traits and specificity of effect on flower visitors. We exposed flowering Brassica nigra plants to six insect herbivore species and recorded changes in flower traits (flower abundance, morphology, colour, volatile emission, nectar quantity, and pollen quantity and size) and the behaviour of two pollinating insects. Our results show that herbivory can affect multiple flower traits and pollinator behaviour. Most plastic floral traits were flower morphology, colour, the composition of the volatile blend, and nectar production. Herbivore-induced changes in flower traits resulted in positive, negative, or neutral effects on pollinator behaviour. Effects on flower traits and pollinator behaviour were herbivore species-specific. Flowers show extensive plasticity in response to antagonist herbivores, with contrasting effects on mutualist pollinators. Antagonists can potentially act as agents of selection on flower traits and plant reproduction via plant-mediated interactions with mutualists.
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Affiliation(s)
- Quint Rusman
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
| | - Erik H. Poelman
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
| | - Farzana Nowrin
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
| | - Gerrit Polder
- Greenhouse HorticultureWageningen University, WageningenThe Netherlands
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13
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Damestoy T, Brachi B, Moreira X, Jactel H, Plomion C, Castagneyrol B. Oak genotype and phenolic compounds differently affect the performance of two insect herbivores with contrasting diet breadth. TREE PHYSIOLOGY 2019; 39:615-627. [PMID: 30668790 DOI: 10.1093/treephys/tpy149] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 12/13/2018] [Accepted: 12/19/2018] [Indexed: 05/16/2023]
Abstract
Research on plant-herbivore interactions has long recognized that plant genetic variation plays a central role in driving insect abundance and herbivory, as well as in determining plant defense. However, how plant genes influence herbivore feeding performances, and which plant defensive traits mediate these effects, remain poorly understood. Here we investigated the feeding performances of two insect leaf chewers with contrasting diet breadth (the generalist Lymantria dispar L. and the specialist Thaumetopoea processionea L.) on different genotypes of pedunculate oak (Quercus robur L.) and tested the role of leaf phenolics. We used leaves from four clones of 30 Q. robur full-sibs grown in a common garden to estimate the performance of both herbivores in laboratory feeding trials and to quantify the concentration of constitutive chemical defences (phenolic compounds). We found that tree genetics influenced leaf consumption by T. processionea but not by L. dispar. However genetic variation among trees did not explain growth rate variation in either herbivore nor in leaf phenolics. Interestingly, all phenolic compounds displayed a positive relationship with L. dispar growth rate, and leaf consumption by both herbivores displayed a positive relationship with the concentrations of condensed tannins, suggesting that highly defended leaves could induce a compensatory feeding response. While genetic variation in oaks did not explain herbivore growth rate, we found positive genetic correlations between the two herbivores for leaf consumption and digestion. Overall, we found that oak genotype and phenolic compounds partly and independently contribute to variability in herbivore performance. We challenged the current view of plant-insect interaction and provided little support to the idea that the effect of plant genotype on associated organisms is driven by plant defences. Together, our results point to the existence of genetically determined resistance traits in oaks whose effects differ between herbivores and motivate further research on mechanisms governing oak-herbivore interactions.
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Affiliation(s)
- Thomas Damestoy
- BIOGECO, INRA, Univ. Bordeaux, 69 route d'Arcachon, Cestas Cedex, France
| | - Benjamin Brachi
- BIOGECO, INRA, Univ. Bordeaux, 69 route d'Arcachon, Cestas Cedex, France
| | - Xoaquín Moreira
- Misión Biológica de Galicia (MBG-CSIC), Apartado de correos 28, Pontevedra, Galicia, Spain
| | - Hervé Jactel
- BIOGECO, INRA, Univ. Bordeaux, 69 route d'Arcachon, Cestas Cedex, France
| | - Christophe Plomion
- BIOGECO, INRA, Univ. Bordeaux, 69 route d'Arcachon, Cestas Cedex, France
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14
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Chen W, Yang X, Tetreau G, Song X, Coutu C, Hegedus D, Blissard G, Fei Z, Wang P. A high‐quality chromosome‐level genome assembly of a generalist herbivore,
Trichoplusia ni. Mol Ecol Resour 2019; 19:485-496. [DOI: 10.1111/1755-0998.12966] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 11/07/2018] [Accepted: 11/12/2018] [Indexed: 01/01/2023]
Affiliation(s)
- Wenbo Chen
- Boyce Thompson Institute Ithaca New York
| | - Xiaowei Yang
- Department of Entomology Cornell University, New York State Agricultural Experiment Station Geneva New York
| | - Guillaume Tetreau
- Department of Entomology Cornell University, New York State Agricultural Experiment Station Geneva New York
| | - Xiaozhao Song
- Department of Entomology Cornell University, New York State Agricultural Experiment Station Geneva New York
| | - Cathy Coutu
- Saskatoon Research and Development Centre, Agriculture and Agri‐Food Canada Saskatoon Saskatchewan Canada
| | - Dwayne Hegedus
- Saskatoon Research and Development Centre, Agriculture and Agri‐Food Canada Saskatoon Saskatchewan Canada
| | | | - Zhangjun Fei
- Boyce Thompson Institute Ithaca New York
- USDA‐Agricultural Research Service, Robert W. Holley Center for Agriculture and Health Ithaca New York
| | - Ping Wang
- Department of Entomology Cornell University, New York State Agricultural Experiment Station Geneva New York
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15
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Danner H, Desurmont GA, Cristescu SM, van Dam NM. Herbivore-induced plant volatiles accurately predict history of coexistence, diet breadth, and feeding mode of herbivores. THE NEW PHYTOLOGIST 2018; 220:726-738. [PMID: 28134434 DOI: 10.1111/nph.14428] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Accepted: 12/08/2016] [Indexed: 05/04/2023]
Abstract
Herbivore-induced plant volatiles (HIPVs) serve as specific cues to higher trophic levels. Novel, exotic herbivores entering native foodwebs may disrupt the infochemical network as a result of changes in HIPV profiles. Here, we analysed HIPV blends of native Brassica rapa plants infested with one of 10 herbivore species with different coexistence histories, diet breadths and feeding modes. Partial least squares (PLS) models were fitted to assess whether HIPV blends emitted by Dutch B. rapa differ between native and exotic herbivores, between specialists and generalists, and between piercing-sucking and chewing herbivores. These models were used to predict the status of two additional herbivores. We found that HIPV blends predicted the evolutionary history, diet breadth and feeding mode of the herbivore with an accuracy of 80% or higher. Based on the HIPVs, the PLS models reliably predicted that Trichoplusia ni and Spodoptera exigua are perceived as exotic, leaf-chewing generalists by Dutch B. rapa plants. These results indicate that there are consistent and predictable differences in HIPV blends depending on global herbivore characteristics, including coexistence history. Consequently, native organisms may be able to rapidly adapt to potentially disruptive effects of exotic herbivores on the infochemical network.
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Affiliation(s)
- Holger Danner
- Molecular Interaction Ecology, Institute for Water and Wetland Research (IWWR), Radboud University, PO Box 9010, 6500, GL Nijmegen, the Netherlands
| | - Gaylord A Desurmont
- Institute of Biology, University of Neuchâtel, Neuchâtel, 2000, Switzerland
- European Biological Control Laboratory, USDA-ARS, CS 90013, Montferrier-sur-Lez, France
| | - Simona M Cristescu
- Life Science Trace Gas Facility, Institute for Molecules and Materials, Radboud University, 6500, GL Nijmegen, the Netherlands
| | - Nicole M van Dam
- Molecular Interaction Ecology, Institute for Water and Wetland Research (IWWR), Radboud University, PO Box 9010, 6500, GL Nijmegen, the Netherlands
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, Leipzig, 04103, Germany
- Institute of Ecology, Friedrich Schiller University Jena, Dornburger-Str. 159, Jena, 07743, Germany
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16
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van Dam NM, Wondafrash M, Mathur V, Tytgat TOG. Differences in Hormonal Signaling Triggered by Two Root-Feeding Nematode Species Result in Contrasting Effects on Aphid Population Growth. Front Ecol Evol 2018. [DOI: 10.3389/fevo.2018.00088] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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17
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Paulo JT, Godinho DP, Silva A, Branquinho C, Magalhães S. Suppression of Plant Defenses by Herbivorous Mites Is Not Associated with Adaptation to Host Plants. Int J Mol Sci 2018; 19:E1783. [PMID: 29914126 PMCID: PMC6032058 DOI: 10.3390/ijms19061783] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 06/12/2018] [Indexed: 11/16/2022] Open
Abstract
Some herbivores suppress plant defenses, which may be viewed as a result of the coevolutionary arms race between plants and herbivores. However, this ability is usually studied in a one-herbivore-one-plant system, which hampers comparative studies that could corroborate this hypothesis. Here, we extend this paradigm and ask whether the herbivorous spider-mite Tetranychus evansi, which suppresses the jasmonic-acid pathway in tomato plants, is also able to suppress defenses in other host plants at different phylogenetic distances from tomatoes. We test this using different plants from the Solanales order, namely tomato, jimsonweed, tobacco, and morning glory (three Solanaceae and one Convolvulaceae), and bean plants (Fabales). First, we compare the performance of T. evansi to that of the other two most-commonly found species of the same genus, T. urticae and T. ludeni, on several plants. We found that the performance of T. evansi is higher than that of the other species only on tomato plants. We then showed, by measuring trypsin inhibitor activity and life history traits of conspecific mites on either clean or pre-infested plants, that T. evansi can suppress plant defenses on all plants except tobacco. This study suggests that the suppression of plant defenses may occur on host plants other than those to which herbivores are adapted.
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Affiliation(s)
- Jéssica T Paulo
- cE3c Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, 1649-004 Lisboa, Portugal.
| | - Diogo P Godinho
- cE3c Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, 1649-004 Lisboa, Portugal.
| | - Anabela Silva
- BioISI, Biosystems and Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, 1649-004 Lisboa, Portugal.
| | - Cristina Branquinho
- cE3c Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, 1649-004 Lisboa, Portugal.
| | - Sara Magalhães
- cE3c Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, 1649-004 Lisboa, Portugal.
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18
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Stam JM, Dicke M, Poelman EH. Order of herbivore arrival on wild cabbage populations influences subsequent arthropod community development. OIKOS 2018. [DOI: 10.1111/oik.05265] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Jeltje M. Stam
- Laboratory of Entomology; Wageningen Univ.; PO Box 16, NL-6700 AA Wageningen the Netherlands
| | - Marcel Dicke
- Laboratory of Entomology; Wageningen Univ.; PO Box 16, NL-6700 AA Wageningen the Netherlands
| | - Erik H. Poelman
- Laboratory of Entomology; Wageningen Univ.; PO Box 16, NL-6700 AA Wageningen the Netherlands
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19
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Chiu YC, Juvik JA, Ku KM. Targeted Metabolomic and Transcriptomic Analyses of "Red Russian" Kale (Brassicae napus var. pabularia) Following Methyl Jasmonate Treatment and Larval Infestation by the Cabbage Looper (Trichoplusia ni Hübner). Int J Mol Sci 2018; 19:E1058. [PMID: 29614820 PMCID: PMC5979517 DOI: 10.3390/ijms19041058] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Revised: 03/24/2018] [Accepted: 03/26/2018] [Indexed: 12/26/2022] Open
Abstract
Methyl jasmonate (MeJA), synthesized in the jasmonic acid (JA) pathway, has been found to upregulate glucosinolate (GS) biosynthesis in plant species of the Brassicaceae family. Exogenous application of MeJA has shown to increase tissue GS concentrations and the formation of myrosinase-mediated GS hydrolysis products (GSHPs). In vitro and in vivo assays have demonstrated the potential health-promoting effects of certain GSHPs. MeJA is also known to elicit and induce genes associated with defense mechanisms to insect herbivory in Brassica species. To investigate the relationship between MeJA-induced GS biosynthesis and insect defense, three treatments were applied to "Red Russian" kale (Brassicae napus var. pabularia) seedlings: (1) a 250 µM MeJA leaf spray treatment; (2) leaf infestation with larvae of the cabbage looper (Trichoplusia ni (Hübner)); (3) control treatment (neither larval infestation nor MeJA application). Samples of leaf tissue from the three treatments were then assayed for changes in GS and GSHP concentrations, GS gene biosynthesis expression, and myrosinase activity. Major differences were observed between the three treatments in the levels of GS accumulation and GS gene expression. The insect-damaged samples showed significantly lower aliphatic GS accumulation, while both MeJA and T. ni infestation treatments induced greater accumulation of indolyl GS. The gene expression levels of CYP81F4, MYB34, and MYB122 were significantly upregulated in samples treated with MeJA and insects compared to the control group, which explained the increased indolyl GS concentration. The results suggest that the metabolic changes promoted by MeJA application and the insect herbivory response share common mechanisms of induction. This work provides potentially useful information for kale pest control and nutritional quality.
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Affiliation(s)
- Yu-Chun Chiu
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV 26506, USA.
| | - John A Juvik
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
| | - Kang-Mo Ku
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, WV 26506, USA.
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20
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Rusman Q, Lucas‐Barbosa D, Poelman EH. Dealing with mutualists and antagonists: Specificity of plant‐mediated interactions between herbivores and flower visitors, and consequences for plant fitness. Funct Ecol 2018. [DOI: 10.1111/1365-2435.13035] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Quint Rusman
- Laboratory of EntomologyWageningen University Wageningen The Netherlands
| | - Dani Lucas‐Barbosa
- Laboratory of EntomologyWageningen University Wageningen The Netherlands
| | - Erik H. Poelman
- Laboratory of EntomologyWageningen University Wageningen The Netherlands
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21
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STAM JELTJEM, CHRÉTIEN LUCILLE, DICKE MARCEL, POELMAN ERIKH. Response of Brassica oleracea to temporal variation in attack by two herbivores affects preference and performance of a third herbivore. ECOLOGICAL ENTOMOLOGY 2017; 42:803-815. [PMID: 29200601 PMCID: PMC5698737 DOI: 10.1111/een.12455] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 06/13/2017] [Accepted: 06/30/2017] [Indexed: 05/21/2023]
Abstract
1. Plants are frequently under attack by multiple insect herbivores, which may interact indirectly through herbivore-induced changes in the plant's phenotype. The identity, order, and timing of herbivore arrivals may influence the outcome of interactions between two herbivores. How these aspects affect, in turn, subsequently arriving herbivores that feed on double herbivore-induced plants has not been widely investigated. 2. This study tested whether the order and timing of arrival of two inducing herbivores from different feeding guilds affected the preference and performance of a subsequently arriving third herbivore, caterpillars of Mamestra brassicae L. (Lepidoptera: Noctuidae). Aphids [Brevicoryne brassicae L. (Hemiptera: Aphididae)] and caterpillars [Plutella xylostella L. (Lepidoptera: Yponomeutidae)] were introduced onto wild Brassica oleracea L. (Brassicaceae) plants in different sequences and with different arrival times. The effects of these plant treatments on M. brassicae caterpillars were assessed in pairwise preference tests and no-choice performance tests. 3. The caterpillars of M. brassicae preferred to feed from undamaged plants rather than double herbivore-induced plants. Compared with undamaged plants, they preferred plant material on which aphids had arrived first followed by caterpillars, whereas they avoided plant material with the reverse order of herbivore arrival. Performance of the caterpillars increased with increasing arrival time between herbivore infestations in double herbivore-induced plants. Although M. brassicae grew faster on plants induced by aphids than on those induced by caterpillars alone, its performance was not affected by the order of previous herbivore arrival. 4. These results imply that the timing of colonisation by multiple herbivores determines the outcome of plant-mediated herbivore-herbivore interactions.
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Affiliation(s)
- JELTJE M. STAM
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
| | - LUCILLE CHRÉTIEN
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
- Biology Department, Master Biosciences, École Normale Supérieure de LyonUniversité Claude Bernard Lyon 1Lyon Cedex 07France
| | - MARCEL DICKE
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
| | - ERIK H. POELMAN
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
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22
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Stolpe C, Giehren F, Krämer U, Müller C. Both heavy metal-amendment of soil and aphid-infestation increase Cd and Zn concentrations in phloem exudates of a metal-hyperaccumulating plant. PHYTOCHEMISTRY 2017; 139:109-117. [PMID: 28437705 DOI: 10.1016/j.phytochem.2017.04.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 04/10/2017] [Accepted: 04/12/2017] [Indexed: 05/28/2023]
Abstract
Plants that are able to hyperaccumulate heavy metals show increased concentrations of these metals in their leaf tissue. However, little is known about the concentrations of heavy metals and of organic defence metabolites in the phloem sap of these plants in response to either heavy metal-amendment of the soil or biotic challenges such as aphid-infestation. In this study, we investigated the effects of heavy metal-exposure and of aphid-infestation on phloem exudate composition of the metal hyperaccumulator species Arabidopsis halleri L. O'Kane & Al-Shehbaz (Brassicaceae). The concentrations of elements and of organic defence compounds, namely glucosinolates, were measured in phloem exudates of young and old (mature) leaves of plants challenged either by amendment of the soil with cadmium and zinc and/or by an infestation with the generalist aphid Myzus persicae. Metal-amendment of the soil led to increased concentrations of Cd and Zn, but also of two other elements and one indole glucosinolate, in phloem exudates. This enhanced defence in the phloem sap of heavy metal-hyperaccumulating plants can thus potentially act as effective protection against aphids, as predicted by the elemental defence hypothesis. Aphid-infestation also caused enhanced Cd and Zn concentrations in phloem exudates. This result provides first evidence that metal-hyperaccumulating plants can increase heavy metal concentrations tissue-specifically in response to an attack by phloem-sucking herbivores. Overall, the concentrations of most elements, including the heavy metals, and glucosinolates were higher in phloem exudates of young leaves than in those of old leaves. This defence distribution highlights that the optimal defence theory, which predicts more valuable tissue to be better defended, is applicable for both inorganic and organic defences.
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Affiliation(s)
- Clemens Stolpe
- Department of Chemical Ecology, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Franziska Giehren
- Department of Chemical Ecology, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany
| | - Ute Krämer
- Department of Molecular Genetics and Physiology of Plants, Ruhr University Bochum, Universitätsstr. 150, 44801 Bochum, Germany
| | - Caroline Müller
- Department of Chemical Ecology, Bielefeld University, Universitätsstr. 25, 33615 Bielefeld, Germany.
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23
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Davila Olivas NH, Frago E, Thoen MPM, Kloth KJ, Becker FFM, van Loon JJA, Gort G, Keurentjes JJB, van Heerwaarden J, Dicke M. Natural variation in life history strategy of Arabidopsis thaliana determines stress responses to drought and insects of different feeding guilds. Mol Ecol 2017; 26:2959-2977. [PMID: 28295823 PMCID: PMC5485070 DOI: 10.1111/mec.14100] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Revised: 02/21/2017] [Accepted: 02/27/2017] [Indexed: 12/31/2022]
Abstract
Plants are sessile organisms and, consequently, are exposed to a plethora of stresses in their local habitat. As a result, different populations of a species are subject to different selection pressures leading to adaptation to local conditions and intraspecific divergence. The annual brassicaceous plant Arabidopsis thaliana is an attractive model for ecologists and evolutionary biologists due to the availability of a large collection of resequenced natural accessions. Accessions of A. thaliana display one of two different life cycle strategies: summer and winter annuals. We exposed a collection of 308 European Arabidopsis accessions, that have been genotyped for 250K SNPs, to a range of stresses: one abiotic stress (drought), four biotic stresses (Pieris rapae caterpillars, Plutella xylostella caterpillars, Frankliniella occidentalis thrips and Myzus persicae aphids) and two combined stresses (drought plus P. rapae and Botrytis cinerea fungus plus P. rapae). We identified heritable genetic variation for responses to the different stresses, estimated by narrow-sense heritability. We found that accessions displaying different life cycle strategies differ in their response to stresses. Winter annuals are more resistant to drought, aphids and thrips and summer annuals are more resistant to P. rapae and P. xylostella caterpillars. Summer annuals are also more resistant to the combined stresses of drought plus P. rapae and infection by the fungus Botryris cinerea plus herbivory by P. rapae. Adaptation to drought displayed a longitudinal gradient. Finally, trade-offs were recorded between the response to drought and responses to herbivory by caterpillars of the specialist herbivore P. rapae.
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Affiliation(s)
| | - Enric Frago
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
| | - Manus P. M. Thoen
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
- Wageningen Plant ResearchWageningen University and ResearchWageningenThe Netherlands
- Laboratory of Plant PhysiologyWageningen UniversityWageningenThe Netherlands
| | - Karen J. Kloth
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
- Wageningen Plant ResearchWageningen University and ResearchWageningenThe Netherlands
- Laboratory of Plant PhysiologyWageningen UniversityWageningenThe Netherlands
| | | | | | - Gerrit Gort
- BiometrisWageningen University and ResearchWageningenThe Netherlands
| | | | | | - Marcel Dicke
- Laboratory of EntomologyWageningen UniversityWageningenThe Netherlands
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24
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Zhou LH, Liu SB, Wang PF, Lu TJ, Xu F, Genin GM, Pickard BG. The Arabidopsis trichome is an active mechanosensory switch. PLANT, CELL & ENVIRONMENT 2017; 40:611-621. [PMID: 26920667 DOI: 10.1111/pce.12728] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 01/15/2016] [Accepted: 01/18/2016] [Indexed: 05/18/2023]
Abstract
Trichomes ('hair cells') on Arabidopsis thaliana stem and leaf surfaces provide a range of benefits arising from their shape and disposition. These include tempting herbivores to sample constitutive toxins before they reach the bulk of the tissue. We asked whether, in addition, small mechanical disturbances such as an insect can make elicit signals that might help the plant respond to herbivory. We imaged, pressed and brushed trichomes in several ways, most notably with confocal microscopy of trichomes transgenically provided with apoplastic pH reporter apo-pHusion and cytosolic Ca2+ reporter cameleon. In parallel, we modelled trichome wall mechanics with finite element analysis. The stimulated trichome focuses force on a pliant zone and the adjoining podium of the stalk. A buckling instability can further focus force on a skirt of cells surrounding the podium, eliciting oscillations of cytosolic Ca2+ and shifts in apoplastic pH. These observations represent active physiological response. Modelling establishes that the effectiveness of force focusing and buckling is due to the peculiar tapering wall structure of the trichome. Hypothetically, these active mechanosensing functions enhance toxin synthesis above constitutive levels, probably via a priming process, thus minimizing the costly accumulation of toxins in the absence of herbivore attack but assuring rapid build-up when needed.
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Affiliation(s)
- Li Hong Zhou
- Department of Mechanical Engineering & Materials Science, Washington University in St. Louis, St. Louis, MO, 63130, USA
- Bioinspired Engineering & Biomechanics Center, Xi'an Jiaotong University, Xi'an, 710049, China
- Gladys Levis Allen Laboratory of Plant Sensory Physiology, Biology Department, Washington University in St. Louis, St. Louis, MO, 63130, USA
| | - Shao Bao Liu
- Department of Mechanical Engineering & Materials Science, Washington University in St. Louis, St. Louis, MO, 63130, USA
- Bioinspired Engineering & Biomechanics Center, Xi'an Jiaotong University, Xi'an, 710049, China
- Gladys Levis Allen Laboratory of Plant Sensory Physiology, Biology Department, Washington University in St. Louis, St. Louis, MO, 63130, USA
| | - Peng Fei Wang
- Bioinspired Engineering & Biomechanics Center, Xi'an Jiaotong University, Xi'an, 710049, China
- Qian Xuesen Laboratory of Space Technology, China Academy of Space Technology, Beijing, 100094, China
| | - Tian Jian Lu
- Bioinspired Engineering & Biomechanics Center, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Feng Xu
- Bioinspired Engineering & Biomechanics Center, Xi'an Jiaotong University, Xi'an, 710049, China
- Ministry of Education Key Laboratory of Biomedical Information Engineering, School of Life Science & Technology, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Guy M Genin
- Department of Mechanical Engineering & Materials Science, Washington University in St. Louis, St. Louis, MO, 63130, USA
- Bioinspired Engineering & Biomechanics Center, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Barbara G Pickard
- Department of Mechanical Engineering & Materials Science, Washington University in St. Louis, St. Louis, MO, 63130, USA
- Gladys Levis Allen Laboratory of Plant Sensory Physiology, Biology Department, Washington University in St. Louis, St. Louis, MO, 63130, USA
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Muto-Fujita A, Takemoto K, Kanaya S, Nakazato T, Tokimatsu T, Matsumoto N, Kono M, Chubachi Y, Ozaki K, Kotera M. Data integration aids understanding of butterfly-host plant networks. Sci Rep 2017; 7:43368. [PMID: 28262809 PMCID: PMC5338290 DOI: 10.1038/srep43368] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 01/23/2017] [Indexed: 12/05/2022] Open
Abstract
Although host-plant selection is a central topic in ecology, its general underpinnings are poorly understood. Here, we performed a case study focusing on the publicly available data on Japanese butterflies. A combined statistical analysis of plant-herbivore relationships and taxonomy revealed that some butterfly subfamilies in different families feed on the same plant families, and the occurrence of this phenomenon more than just by chance, thus indicating the independent acquisition of adaptive phenotypes to the same hosts. We consequently integrated plant-herbivore and plant-compound relationship data and conducted a statistical analysis to identify compounds unique to host plants of specific butterfly families. Some of the identified plant compounds are known to attract certain butterfly groups while repelling others. The additional incorporation of insect-compound relationship data revealed potential metabolic processes that are related to host plant selection. Our results demonstrate that data integration enables the computational detection of compounds putatively involved in particular interspecies interactions and that further data enrichment and integration of genomic and transcriptomic data facilitates the unveiling of the molecular mechanisms involved in host plant selection.
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Affiliation(s)
- Ai Muto-Fujita
- Graduate School of Biological Sciences, Nara Institute of Science and Technology (NAIST), 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
| | - Kazuhiro Takemoto
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, Kawazu 680-4, Iizuka, Fukuoka 820-8502, Japan
| | - Shigehiko Kanaya
- Graduate School of Information Sciences, Nara Institute of Science and Technology (NAIST), 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
| | - Takeru Nakazato
- Database Center for Life Science (DBCLS), Research Organization of Information and Systems, Yata 1111, Mishima, Shizuoka 411-8540, Japan
| | - Toshiaki Tokimatsu
- DDBJ Center, National Institute of Genetics, Research Organization of Information and Systems, Yata 1111, Mishima, Shizuoka 411-8540, Japan
| | | | - Mayo Kono
- School of Life Science and Technology, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Yuko Chubachi
- School of Life Science and Technology, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
| | - Katsuhisa Ozaki
- JT Biohistory Research Hall, 1-1 Murasaki-cho, Takatsuki, Osaka 569-1125, Japan
| | - Masaaki Kotera
- School of Life Science and Technology, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
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26
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Davila Olivas NH, Kruijer W, Gort G, Wijnen CL, van Loon JJA, Dicke M. Genome-wide association analysis reveals distinct genetic architectures for single and combined stress responses in Arabidopsis thaliana. THE NEW PHYTOLOGIST 2017; 213:838-851. [PMID: 27604707 PMCID: PMC5217058 DOI: 10.1111/nph.14165] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 07/11/2016] [Indexed: 05/20/2023]
Abstract
Plants are commonly exposed to abiotic and biotic stresses. We used 350 Arabidopsis thaliana accessions grown under controlled conditions. We employed genome-wide association analysis to investigate the genetic architecture and underlying loci involved in genetic variation in resistance to: two specialist insect herbivores, Pieris rapae and Plutella xylostella; and combinations of stresses, i.e. drought followed by P. rapae and infection by the fungal pathogen Botrytis cinerea followed by infestation by P. rapae. We found that genetic variation in resistance to combined stresses by drought plus P. rapae was limited compared with B. cinerea plus P. rapae or P. rapae alone. Resistance to the two caterpillars is controlled by different genetic components. There is limited overlap in the quantitative trait loci (QTLs) underlying resistance to combined stresses by drought plus P. rapae or B. cinerea plus P. rapae and P. rapae alone. Finally, several candidate genes involved in the biosynthesis of aliphatic glucosinolates and proteinase inhibitors were identified to be involved in resistance to P. rapae and P. xylostella, respectively. This study underlines the importance of investigating plant responses to combinations of stresses. The value of this approach for breeding plants for resistance to combinatorial stresses is discussed.
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Affiliation(s)
| | - Willem Kruijer
- BiometrisWageningen UniversityPO Box 166700 AAWageningenthe Netherlands
| | - Gerrit Gort
- BiometrisWageningen UniversityPO Box 166700 AAWageningenthe Netherlands
| | - Cris L. Wijnen
- Laboratory of EntomologyWageningen UniversityPO Box 166700 AAWageningenthe Netherlands
| | - Joop J. A. van Loon
- Laboratory of EntomologyWageningen UniversityPO Box 166700 AAWageningenthe Netherlands
| | - Marcel Dicke
- Laboratory of EntomologyWageningen UniversityPO Box 166700 AAWageningenthe Netherlands
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27
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Kroes A, Stam JM, David A, Boland W, van Loon JJA, Dicke M, Poelman EH. Plant-mediated interactions between two herbivores differentially affect a subsequently arriving third herbivore in populations of wild cabbage. PLANT BIOLOGY (STUTTGART, GERMANY) 2016; 18:981-991. [PMID: 27492059 DOI: 10.1111/plb.12490] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Accepted: 08/01/2016] [Indexed: 06/06/2023]
Abstract
Plants are part of biodiverse communities and frequently suffer from attack by multiple herbivorous insects. Plant responses to these herbivores are specific for insect feeding guilds: aphids and caterpillars induce different plant phenotypes. Moreover, plants respond differentially to single or dual herbivory, which may cascade into a chain of interactions in terms of resistance to other community members. Whether differential responses to single or dual herbivory have consequences for plant resistance to yet a third herbivore is unknown. We assessed the effects of single or dual herbivory by Brevicoryne brassicae aphids and/or Plutella xylostella caterpillars on resistance of plants from three natural populations of wild cabbage to feeding by caterpillars of Mamestra brassicae. We measured plant gene expression and phytohormone concentrations to illustrate mechanisms involved in induced responses. Performance of both B. brassicae and P. xylostella was reduced when feeding simultaneously with the other herbivore, compared to feeding alone. Gene expression and phytohormone concentrations in plants exposed to dual herbivory were different from those found in plants exposed to herbivory by either insect alone. Plants previously induced by both P. xylostella and B. brassicae negatively affected growth of the subsequently arriving M. brassicae. Furthermore, induced responses varied between wild cabbage populations. Feeding by multiple herbivores differentially activates plant defences, which has plant-mediated negative consequences for a subsequently arriving herbivore. Plant population-specific responses suggest that plant populations adapt to the specific communities of insect herbivores. Our study contributes to the understanding of plant defence plasticity in response to multiple insect attacks.
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Affiliation(s)
- A Kroes
- Laboratory of Entomology, Wageningen University, Wageningen, the Netherlands.
| | - J M Stam
- Laboratory of Entomology, Wageningen University, Wageningen, the Netherlands.
| | - A David
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - W Boland
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - J J A van Loon
- Laboratory of Entomology, Wageningen University, Wageningen, the Netherlands
| | - M Dicke
- Laboratory of Entomology, Wageningen University, Wageningen, the Netherlands
| | - E H Poelman
- Laboratory of Entomology, Wageningen University, Wageningen, the Netherlands
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Kroes A, Broekgaarden C, Castellanos Uribe M, May S, van Loon JJA, Dicke M. Brevicoryne brassicae aphids interfere with transcriptome responses of Arabidopsis thaliana to feeding by Plutella xylostella caterpillars in a density-dependent manner. Oecologia 2016; 183:107-120. [PMID: 27771762 PMCID: PMC5239811 DOI: 10.1007/s00442-016-3758-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Accepted: 10/16/2016] [Indexed: 01/09/2023]
Abstract
Plants are commonly attacked by multiple herbivorous species. Yet, little is known about transcriptional patterns underlying plant responses to multiple insect attackers feeding simultaneously. Here, we assessed transcriptomic responses of Arabidopsis thaliana plants to simultaneous feeding by Plutella xylostella caterpillars and Brevicoryne brassicae aphids in comparison to plants infested by P. xylostella caterpillars alone, using microarray analysis. We particularly investigated how aphid feeding interferes with the transcriptomic response to P. xylostella caterpillars and whether this interference is dependent on aphid density and time since aphid attack. Various JA-responsive genes were up-regulated in response to feeding by P. xylostella caterpillars. The additional presence of aphids, both at low and high densities, clearly affected the transcriptional plant response to caterpillars. Interestingly, some important modulators of plant defense signalling, including WRKY transcription factor genes and ABA-dependent genes, were differentially induced in response to simultaneous aphid feeding at low or high density compared with responses to P. xylostella caterpillars feeding alone. Furthermore, aphids affected the P. xylostella-induced transcriptomic response in a density-dependent manner, which caused an acceleration in plant response against dual insect attack at high aphid density compared to dual insect attack at low aphid density. In conclusion, our study provides evidence that aphids influence the caterpillar-induced transcriptional response of A. thaliana in a density-dependent manner. It highlights the importance of addressing insect density to understand how plant responses to single attackers interfere with responses to other attackers and thus underlines the importance of the dynamics of transcriptional plant responses to multiple herbivory.
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Affiliation(s)
- Anneke Kroes
- Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands.
| | - Colette Broekgaarden
- Plant-Microbe Interactions, Department of Biology, Faculty of Science, Utrecht University, 3508 TB, Utrecht, The Netherlands
| | - Marcos Castellanos Uribe
- Nottingham Arabidopsis Stock Centre, University of Nottingham, School of Biosciences, Loughborough, LE12 5RD, UK
| | - Sean May
- Nottingham Arabidopsis Stock Centre, University of Nottingham, School of Biosciences, Loughborough, LE12 5RD, UK
| | - Joop J A van Loon
- Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands
| | - Marcel Dicke
- Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands
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29
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Different Narrow-Band Light Ranges Alter Plant Secondary Metabolism and Plant Defense Response to Aphids. J Chem Ecol 2016; 42:989-1003. [PMID: 27589867 DOI: 10.1007/s10886-016-0755-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Revised: 06/15/2016] [Accepted: 07/01/2016] [Indexed: 10/21/2022]
Abstract
Light of different wavelengths affects various physiological processes in plants. Short-wavelength radiation (like UV) can activate defense pathways in plants and enhance the biosynthesis of secondary metabolites (such as flavonoids and glucosinolates) responsible for resistance against certain herbivorous insects. The intensity of light-induced, metabolite-based resistance is plant- and insect species-specific and depends on herbivore feeding guild and specialization. In this study, broccoli (Brassica oleracea var. italica) plants were grown for 4 weeks in a climate chamber under conventional fluorescent tubes and were additionally treated with UV-B (310 nm), UV-A (365 or 385 nm), or violet (420 nm) light generated with UV-B tubes or light-emitting diodes (LEDs). The objective was to determine the influence of narrow bandwidths of light (from UV-B to violet) on plant secondary metabolism and on the performance of the cabbage aphid Brevicoryne brassicae (a specialist) and the green peach aphid Myzus persicae (a generalist). Among flavonol glycosides, specific quercetin and kaempferol glycosides increased markedly under UV-B, while among glucosinolates only 4-methoxy-3-indolylmethyl showed a 2-fold increase in plants exposed to UV-B and UV-A. The concentration of 3-indolylmethyl glucosinolate in broccoli plants increased with UV-B treatment. Brevicoryne brassicae adult weights and fecundity were lower on UV-B treated plants compared to UV-A or violet light-treated plants. Adult weights and fecundity of M. persicae were increased under UV-B and UV-A treatments. When specific light wavelengths are used to induce metabolic changes in plants, the specificity of the induced effects on herbivores should be considered.
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30
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Nguyen D, Rieu I, Mariani C, van Dam NM. How plants handle multiple stresses: hormonal interactions underlying responses to abiotic stress and insect herbivory. PLANT MOLECULAR BIOLOGY 2016; 91:727-40. [PMID: 27095445 PMCID: PMC4932144 DOI: 10.1007/s11103-016-0481-8] [Citation(s) in RCA: 155] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Accepted: 04/09/2016] [Indexed: 05/18/2023]
Abstract
Adaptive plant responses to specific abiotic stresses or biotic agents are fine-tuned by a network of hormonal signaling cascades, including abscisic acid (ABA), ethylene, jasmonic acid (JA) and salicylic acid. Moreover, hormonal cross-talk modulates plant responses to abiotic stresses and defenses against insect herbivores when they occur simultaneously. How such interactions affect plant responses under multiple stresses, however, is less understood, even though this may frequently occur in natural environments. Here, we review our current knowledge on how hormonal signaling regulates abiotic stress responses and defenses against insects, and discuss the few recent studies that attempted to dissect hormonal interactions occurring under simultaneous abiotic stress and herbivory. Based on this we hypothesize that drought stress enhances insect resistance due to synergistic interactions between JA and ABA signaling. Responses to flooding or waterlogging involve ethylene signaling, which likely reduces plant resistance to chewing herbivores due to its negative cross-talk with JA. However, the outcome of interactions between biotic and abiotic stress signaling is often plant and/or insect species-dependent and cannot simply be predicted based on general knowledge on the involvement of signaling pathways in single stress responses. More experimental data on non-model plant and insect species are needed to reveal general patterns and better understand the molecular mechanisms allowing plants to optimize their responses in complex environments.
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Affiliation(s)
- Duy Nguyen
- Molecular Plant Physiology, Institute for Water and Wetland Research (IWWR), Radboud University, PO Box 9010, 6500 GL, Nijmegen, The Netherlands
| | - Ivo Rieu
- Molecular Plant Physiology, Institute for Water and Wetland Research (IWWR), Radboud University, PO Box 9010, 6500 GL, Nijmegen, The Netherlands
| | - Celestina Mariani
- Molecular Plant Physiology, Institute for Water and Wetland Research (IWWR), Radboud University, PO Box 9010, 6500 GL, Nijmegen, The Netherlands
| | - Nicole M van Dam
- Molecular Plant Physiology, Institute for Water and Wetland Research (IWWR), Radboud University, PO Box 9010, 6500 GL, Nijmegen, The Netherlands.
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103, Leipzig, Germany.
- Institute of Ecology, Friedrich Schiller University Jena, Dornburger-Str. 159, 07743, Jena, Germany.
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31
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Li Y, Dicke M, Kroes A, Liu W, Gols R. Interactive Effects of Cabbage Aphid and Caterpillar Herbivory on Transcription of Plant Genes Associated with Phytohormonal Signalling in Wild Cabbage. J Chem Ecol 2016; 42:793-805. [PMID: 27530535 PMCID: PMC5045842 DOI: 10.1007/s10886-016-0738-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 06/01/2016] [Accepted: 07/07/2016] [Indexed: 10/25/2022]
Abstract
Plants are commonly attacked by a variety of insect herbivores and have developed specific defenses against different types of attackers. At the molecular level, herbivore-specific signalling pathways are activated by plants in response to attackers with different feeding strategies. Feeding by leaf-chewing herbivores predominantly activates jasmonic acid (JA)-regulated defenses, whereas feeding by phloem-sucking herbivores generally activates salicylic acid (SA)-regulated defenses. When challenged sequentially by both phloem-sucking and leaf-chewing herbivores, SA-JA antagonism may constrain the plant's ability to timely and adequately divert defense to the second herbivore that requires activation of a different defensive pathway. We investigated the effect of the temporal sequence of infestation by the aphid Brevicoryne brassicae and three caterpillar species, Plutella xylostella, Pieris brassicae, and Mamestra brassicae, on the interaction between JA and SA signal-transduction pathways in three wild cabbage populations. We found no support for SA-JA antagonism, irrespective of the temporal sequence of herbivore introduction or the identity of the caterpillar species based on the transcript levels of the JA- and SA-regulated marker genes LOX and PR-1, respectively, at the examined time points, 6, 24, and 48 h. In general, infestation with aphids alone had little effect on the transcript levels of the two marker genes, whereas the three caterpillar species upregulated not only LOX but also PR-1. Transcriptional changes were different for plants from the three different natural cabbage populations.
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Affiliation(s)
- Yehua Li
- Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands
| | - Marcel Dicke
- Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands
| | - Anneke Kroes
- Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands
| | - Wen Liu
- Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands
| | - Rieta Gols
- Laboratory of Entomology, Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands.
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32
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Dicke M. Plant phenotypic plasticity in the phytobiome: a volatile issue. CURRENT OPINION IN PLANT BIOLOGY 2016; 32:17-23. [PMID: 27267277 DOI: 10.1016/j.pbi.2016.05.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 05/20/2016] [Accepted: 05/24/2016] [Indexed: 05/09/2023]
Abstract
Plants live in a diverse and dynamic phytobiome, consisting of a microbiome as well as a macrobiome. They respond to arthropod herbivory with the emission of herbivore-induced plant volatiles (HIPV) that are public information and can be used by any member of the phytobiome. Other members of the phytobiome, which do not directly participate in the interaction, may both modulate the induction of HIPV in the plant, as well as respond to the volatiles. The use of HIPV by individual phytobiome members may have beneficial as well as detrimental consequences for the plant. The collective result of phytobiome-modulated HIPV emission on the responses of phytobiome members and the resulting phytobiome dynamics will determine whether and under which circumstances HIPV emission has a net benefit to the plant or not. Only when we understand HIPV emission in the total phytobiome context can we understand the evolutionary consequences of HIPV emission by plants.
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Affiliation(s)
- Marcel Dicke
- Laboratory of Entomology, Wageningen University, Droevendaalsesteeg 1, 6708PB Wageningen, The Netherlands.
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33
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Davila Olivas NH, Coolen S, Huang P, Severing E, van Verk MC, Hickman R, Wittenberg AHJ, de Vos M, Prins M, van Loon JJA, Aarts MGM, van Wees SCM, Pieterse CMJ, Dicke M. Effect of prior drought and pathogen stress on Arabidopsis transcriptome changes to caterpillar herbivory. THE NEW PHYTOLOGIST 2016; 210:1344-56. [PMID: 26847575 DOI: 10.1111/nph.13847] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 12/06/2015] [Indexed: 05/07/2023]
Abstract
In nature, plants are exposed to biotic and abiotic stresses that often occur simultaneously. Therefore, plant responses to combinations of stresses are most representative of how plants respond to stresses. We used RNAseq to assess temporal changes in the transcriptome of Arabidopsis thaliana to herbivory by Pieris rapae caterpillars, either alone or in combination with prior exposure to drought or infection with the necrotrophic fungus Botrytis cinerea. Pre-exposure to drought stress or Botrytis infection resulted in a significantly different timing of the caterpillar-induced transcriptional changes. Additionally, the combination of drought and P. rapae induced an extensive downregulation of A. thaliana genes involved in defence against pathogens. Despite a more substantial growth reduction observed for plants exposed to drought plus P. rapae feeding compared with P. rapae feeding alone, this did not affect weight increase of this specialist caterpillar. Plants respond to combined stresses with phenotypic and transcriptional changes that differ from the single stress situation. The effect of a previous exposure to drought or B. cinerea infection on transcriptional changes to caterpillars is largely overridden by the stress imposed by caterpillars, indicating that plants shift their response to the most recent stress applied.
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Affiliation(s)
- Nelson H Davila Olivas
- Laboratory of Entomology, Wageningen University, PO Box 16, 6700 AA, Wageningen, the Netherlands
| | - Silvia Coolen
- Plant-Microbe Interactions, Department of Biology, Utrecht University, PO Box 800.56, 3508 TB, Utrecht, the Netherlands
| | - Pingping Huang
- Laboratory of Genetics, Wageningen University, PO Box 16, 6700 AA, Wageningen, the Netherlands
| | - Edouard Severing
- Laboratory of Genetics, Wageningen University, PO Box 16, 6700 AA, Wageningen, the Netherlands
| | - Marcel C van Verk
- Plant-Microbe Interactions, Department of Biology, Utrecht University, PO Box 800.56, 3508 TB, Utrecht, the Netherlands
- Bioinformatics, Utrecht University, PO Box 800.56, 3508 TB, Utrecht, the Netherlands
| | - Richard Hickman
- Plant-Microbe Interactions, Department of Biology, Utrecht University, PO Box 800.56, 3508 TB, Utrecht, the Netherlands
| | | | - Martin de Vos
- Keygene N.V., PO Box 216, 6700 AE, Wageningen, the Netherlands
| | - Marcel Prins
- Keygene N.V., PO Box 216, 6700 AE, Wageningen, the Netherlands
| | - Joop J A van Loon
- Laboratory of Entomology, Wageningen University, PO Box 16, 6700 AA, Wageningen, the Netherlands
| | - Mark G M Aarts
- Laboratory of Genetics, Wageningen University, PO Box 16, 6700 AA, Wageningen, the Netherlands
| | - Saskia C M van Wees
- Plant-Microbe Interactions, Department of Biology, Utrecht University, PO Box 800.56, 3508 TB, Utrecht, the Netherlands
| | - Corné M J Pieterse
- Plant-Microbe Interactions, Department of Biology, Utrecht University, PO Box 800.56, 3508 TB, Utrecht, the Netherlands
| | - Marcel Dicke
- Laboratory of Entomology, Wageningen University, PO Box 16, 6700 AA, Wageningen, the Netherlands
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Lortzing T, Steppuhn A. Jasmonate signalling in plants shapes plant-insect interaction ecology. CURRENT OPINION IN INSECT SCIENCE 2016; 14:32-39. [PMID: 27436644 DOI: 10.1016/j.cois.2016.01.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 01/13/2016] [Accepted: 01/14/2016] [Indexed: 05/11/2023]
Abstract
The phytohormone jasmonic acid (JA) regulates the induction of direct and indirect defences against herbivores. By now, the biochemical pathway of JA-signalling has been well resolved, allowing the use of an interdisciplinary toolbox and spurring the mechanistic investigation of plant-insect interactions. Recent advances show that JA-mediated plant responses are involved in the competitive and trophic interactions between various organisms throughout at least four trophic levels and therefore likely shape natural communities. Moreover, JA-mediated responses can be primed or suppressed by various environmental factors that are related to herbivory or not. Yet, to integrate the complex interactions at the physiological and ecological levels into community ecology, an examination of the often onetime discoveries for general rules and new bioinformatic approaches are required.
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Affiliation(s)
- Tobias Lortzing
- Molecular Ecology, Dahlem Centre of Plant Sciences, Institute of Biology/Freie Universität Berlin, Haderslebener Str. 9, Berlin 12163, Germany.
| | - Anke Steppuhn
- Molecular Ecology, Dahlem Centre of Plant Sciences, Institute of Biology/Freie Universität Berlin, Haderslebener Str. 9, Berlin 12163, Germany.
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35
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Su Q, Mescher MC, Wang S, Chen G, Xie W, Wu Q, Wang W, Zhang Y. Tomato yellow leaf curl virus differentially influences plant defence responses to a vector and a non-vector herbivore. PLANT, CELL & ENVIRONMENT 2016; 39:597-607. [PMID: 26436779 DOI: 10.1111/pce.12650] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 09/20/2015] [Indexed: 06/05/2023]
Abstract
Plants frequently engage in simultaneous interactions with diverse classes of biotic antagonists. Differential induction of plant defence pathways by these antagonists, and interactions between pathways, can have important ecological implications; however, these effects are currently not well understood. We explored how Tomato yellow leaf curl virus (TYLCV) influenced the performance of its vector (Bemisia tabaci) and a non-vector herbivore (Tetranychus urticae) occurring separately or together on tomato plants (Solanum lycopersicum). TYLCV enhanced the performance of B. tabaci, although this effect was statistically significant only in the absence of T. urticae, which adversely affected B. tabaci performance regardless of infection status. In contrast, the performance of T. urticae was enhanced (only) by the combined presence of TYLCV and B. tabaci. Analyses of phytohormone levels and defence gene expression in wild-type tomatoes and various plant-defence mutants indicate that the enhancement of herbivore performance (for each species) entails the disruption of downstream defences in the jasmonic acid (JA) pathway. For T. urticae, this disruption appears to involve antagonistic effects of salicylic acid (SA), which is cumulatively induced to high levels by B. tabaci and TYLCV. In contrast, TYLCV was found to suppress JA-mediated responses to B. tabaci via mechanisms independent of SA.
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Affiliation(s)
- Qi Su
- College of Agriculture, Yangtze University, Jingzhou, Hubei, 434025, China
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Mark C Mescher
- Department of Environmental Systems Science, ETH Zürich, Zürich, 8092, Switzerland
| | - Shaoli Wang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Gong Chen
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Wen Xie
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Qingjun Wu
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Wenkai Wang
- College of Agriculture, Yangtze University, Jingzhou, Hubei, 434025, China
| | - Youjun Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
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Hol WHG, Raaijmakers CE, Mons I, Meyer KM, van Dam NM. Root-Lesion Nematodes Suppress Cabbage Aphid Population Development by Reducing Aphid Daily Reproduction. FRONTIERS IN PLANT SCIENCE 2016; 7:111. [PMID: 26904074 PMCID: PMC4748742 DOI: 10.3389/fpls.2016.00111] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 01/21/2016] [Indexed: 06/01/2023]
Abstract
Empirical studies have shown that belowground feeding herbivores can affect the performance of aboveground herbivores in different ways. Often the critical life-history parameters underlying the observed performance effects remain unexplored. In order to better understand the cause for the observed effects on aboveground herbivores, these ecological mechanisms must be better understood. In this study we combined empirical experiments with a modeling approach to analyze the effect of two root feeding endoparasitic nematodes with different feeding strategies on the population growth of the aboveground feeding specialist aphid Brevicoryne brassicae on Brassica nigra. The aim was to test whether emerging differences in life history characteristics (days until reproduction, daily reproduction) would be sufficient to explain observed differences in aphid population development on plants with and without two species of nematodes. Aphid numbers were lower on plants with Pratylenchus penetrans in comparison to aphid numbers on plants with Meloidogyne spp. A dedicated experiment showed that aphid daily reproduction was lower on plants with P. penetrans (3.08 offspring female(-1) day(-1)) in comparison to both uninfested plants and plants with Meloidogyne spp. (3.50 offspring female(-1) day(-1)). The species-specific reduction of aphid reproduction appeared independent of changes in amino acids, soluble sugars or the glucosinolate sinigrin in the phloem. An individual-based model revealed that relatively small differences in reproduction rate per female were sufficient to yield a similar difference in aphid populations as was found in the empirical experiments.
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Affiliation(s)
- W. H. G. Hol
- Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW)Wageningen, Netherlands
| | - Ciska E. Raaijmakers
- Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW)Wageningen, Netherlands
| | - Ilse Mons
- Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW)Wageningen, Netherlands
| | - Katrin M. Meyer
- Department of Ecosystem Modelling, University of GöttingenGöttingen, Germany
| | - Nicole M. van Dam
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-LeipzigLeipzig, Germany
- Institute of Ecology, Friedrich Schiller University JenaJena Germany
- Molecular Interaction Ecology, Institute of Water and Wetland Research, Radboud UniversityNijmegen Netherlands
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Ogran A, Landau N, Hanin N, Levy M, Gafni Y, Barazani O. Intraspecific variation in defense against a generalist lepidopteran herbivore in populations of Eruca sativa (Mill.). Ecol Evol 2016; 6:363-74. [PMID: 26811800 PMCID: PMC4716514 DOI: 10.1002/ece3.1805] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 09/28/2015] [Accepted: 09/30/2015] [Indexed: 12/22/2022] Open
Abstract
Populations of Eruca sativa (Brassicaceae) from desert and Mediterranean (Med) habitats in Israel differ in their defense against larvae of the generalist Spodoptera littoralis but not the specialist Pieris brassicae. Larvae of the generalist insect feeding on plants of the Med population gained significantly less weight than those feeding on the desert plants, and exogenous application of methyl jasmonate (MJ) on leaves of the Med plants significantly reduced the level of damage created by the generalist larvae. However, MJ treatment significantly induced resistance in plants of the desert population, whereas the generalist larvae caused similar damage to MJ-induced and noninduced plants. Analyses of glucosinolates and expression of genes in their synthesis pathway indicated that defense in plants of the Med population against the generalist insect is governed by the accumulation of glucosinolates. In plants of the desert population, trypsin proteinase inhibitor activity was highly induced in response to herbivory by S. littoralis. Analysis of genes in the defense-regulating signaling pathways suggested that in response to herbivory, differences between populations in the induced levels of jasmonic acid, ethylene, and salicylic acid mediate the differential defenses against the insect. In addition, expression analysis of myrosinase-associated protein NSP2 suggested that in plants of the desert population, glucosinolates breakdown products were primarily directed to nitrile production. We suggest that proteinase inhibitors provide an effective defense in the desert plants, in which glucosinolate production is directed to the less toxic nitriles. The ecological role of nitrile production in preventing infestation by specialists is discussed.
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Affiliation(s)
- Ariel Ogran
- Institute of Plant Sciences Agricultural Research Organization The Volcani Center Bet Dagan 50250 Israel; The Mina & Everard Goodman Faculty of Life Sciences Bar Ilan University Ramat Gan 5290002 Israel
| | - Netanel Landau
- Institute of Plant Sciences Agricultural Research Organization The Volcani Center Bet Dagan 50250 Israel; The Robert H. Smith Faculty of Agriculture Food and Environment The Hebrew University of Jerusalem Rehovot 76100 Israel
| | - Nir Hanin
- Institute of Plant Sciences Agricultural Research Organization The Volcani Center Bet Dagan 50250 Israel
| | - Maggie Levy
- The Robert H. Smith Faculty of Agriculture Food and Environment The Hebrew University of Jerusalem Rehovot 76100 Israel
| | - Yedidya Gafni
- Institute of Plant Sciences Agricultural Research Organization The Volcani Center Bet Dagan 50250 Israel
| | - Oz Barazani
- Institute of Plant Sciences Agricultural Research Organization The Volcani Center Bet Dagan 50250 Israel
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Zhu F, Broekgaarden C, Weldegergis BT, Harvey JA, Vosman B, Dicke M, Poelman EH. Parasitism overrides herbivore identity allowing hyperparasitoids to locate their parasitoid host using herbivore-induced plant volatiles. Mol Ecol 2015; 24:2886-99. [DOI: 10.1111/mec.13164] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 03/13/2015] [Indexed: 12/30/2022]
Affiliation(s)
- Feng Zhu
- Laboratory of Entomology; Wageningen University; Wageningen The Netherlands
| | - Colette Broekgaarden
- Wageningen UR Plant Breeding; Wageningen University; Wageningen The Netherlands
- Plant-Microbe Interactions; Department of Biology; Utrecht University; Utrecht The Netherlands
| | | | - Jeffrey A. Harvey
- Department of Terrestrial Ecology; Netherlands Institute of Ecology; Wageningen The Netherlands
| | - Ben Vosman
- Wageningen UR Plant Breeding; Wageningen University; Wageningen The Netherlands
| | - Marcel Dicke
- Laboratory of Entomology; Wageningen University; Wageningen The Netherlands
| | - Erik H. Poelman
- Laboratory of Entomology; Wageningen University; Wageningen The Netherlands
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Johnson D, Gilbert L. Interplant signalling through hyphal networks. THE NEW PHYTOLOGIST 2015; 205:1448-1453. [PMID: 25421970 DOI: 10.1111/nph.13115] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 09/12/2014] [Indexed: 05/08/2023]
Abstract
Mycorrhizal fungi can form common mycelial networks (CMNs) that interconnect plants. Here, we provide an insight into recent findings demonstrating that CMNs can be conduits for interplant signalling, influencing defence against insect herbivores and foliar necrotrophic fungi. A likely mechanism is direct transfer of signalling molecules within hyphae. However, electrical signals, which can be induced by wounding, may also enable signalling over relatively long distances, because the biophysical constraints imposed by liquid transport in hyphae and interaction with soil are relieved. We do not yet understand the ecological, evolutionary and agronomic implications of interplant signalling via CMNs. Identifying the mechanism of interplant signalling will help to address these gaps.
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Affiliation(s)
- David Johnson
- Institute of Biological and Environmental Sciences, University of Aberdeen, Cruickshank Building, Aberdeen, AB24 3UU, UK
| | - Lucy Gilbert
- Ecological Sciences Group, The James Hutton Institute, Craigiebuckler, Aberdeen, AB15 8QH, UK
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Song YY, Simard SW, Carroll A, Mohn WW, Zeng RS. Defoliation of interior Douglas-fir elicits carbon transfer and stress signalling to ponderosa pine neighbors through ectomycorrhizal networks. Sci Rep 2015; 5:8495. [PMID: 25683155 PMCID: PMC4329569 DOI: 10.1038/srep08495] [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: 11/02/2014] [Accepted: 01/20/2015] [Indexed: 01/01/2023] Open
Abstract
Extensive regions of interior Douglas-fir (Pseudotsuga menziesii var. glauca, IDF) forests in North America are being damaged by drought and western spruce budworm (Choristoneura occidentalis). This damage is resulting from warmer and drier summers associated with climate change. To test whether defoliated IDF can directly transfer resources to ponderosa pine (Pinus ponderosae) regenerating nearby, thus aiding in forest recovery, we examined photosynthetic carbon transfer and defense enzyme response. We grew pairs of ectomycorrhizal IDF 'donor' and ponderosa pine 'receiver' seedlings in pots and isolated transfer pathways by comparing 35 μm, 0.5 μm and no mesh treatments; we then stressed IDF donors either through manual defoliation or infestation by the budworm. We found that manual defoliation of IDF donors led to transfer of photosynthetic carbon to neighboring receivers through mycorrhizal networks, but not through soil or root pathways. Both manual and insect defoliation of donors led to increased activity of peroxidase, polyphenol oxidase and superoxide dismutase in the ponderosa pine receivers, via a mechanism primarily dependent on the mycorrhizal network. These findings indicate that IDF can transfer resources and stress signals to interspecific neighbors, suggesting ectomycorrhizal networks can serve as agents of interspecific communication facilitating recovery and succession of forests after disturbance.
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Affiliation(s)
- Yuan Yuan Song
- College of Life Sciences, Fujian Agriculture and Forestry University, Jinshan, Fuzhou 350002, P.R. China
| | - Suzanne W. Simard
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, British Columbia, V6T 1Z4, Canada
| | - Allan Carroll
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, British Columbia, V6T 1Z4, Canada
| | - William W. Mohn
- Department of Microbiology & Immunology, Life Sciences Institute, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - Ren Sen Zeng
- College of Life Sciences, Fujian Agriculture and Forestry University, Jinshan, Fuzhou 350002, P.R. China
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Barah P, Bones AM. Multidimensional approaches for studying plant defence against insects: from ecology to omics and synthetic biology. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:479-93. [PMID: 25538257 DOI: 10.1093/jxb/eru489] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The biggest challenge for modern biology is to integrate multidisciplinary approaches towards understanding the organizational and functional complexity of biological systems at different hierarchies, starting from the subcellular molecular mechanisms (microscopic) to the functional interactions of ecological communities (macroscopic). The plant-insect interaction is a good model for this purpose with the availability of an enormous amount of information at the molecular and the ecosystem levels. Changing global climatic conditions are abruptly resetting plant-insect interactions. Integration of discretely located heterogeneous information from the ecosystem to genes and pathways will be an advantage to understand the complexity of plant-insect interactions. This review will present the recent developments in omics-based high-throughput experimental approaches, with particular emphasis on studying plant defence responses against insect attack. The review highlights the importance of using integrative systems approaches to study plant-insect interactions from the macroscopic to the microscopic level. We analyse the current efforts in generating, integrating and modelling multiomics data to understand plant-insect interaction at a systems level. As a future prospect, we highlight the growing interest in utilizing the synthetic biology platform for engineering insect-resistant plants.
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Affiliation(s)
- Pankaj Barah
- Cell Molecular Biology and Genomics Group, Department of Biology, Norwegian University of Science and Technology (NTNU), N 7491 Trondheim, Norway
| | - Atle M Bones
- Cell Molecular Biology and Genomics Group, Department of Biology, Norwegian University of Science and Technology (NTNU), N 7491 Trondheim, Norway
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Kroes A, van Loon JJA, Dicke M. Density-dependent interference of aphids with caterpillar-induced defenses in Arabidopsis: involvement of phytohormones and transcription factors. PLANT & CELL PHYSIOLOGY 2015; 56:98-106. [PMID: 25339349 DOI: 10.1093/pcp/pcu150] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
In nature, plants are exposed to attacks by multiple herbivore species at the same time. To cope with these attacks, plants regulate defenses with the production of hormones such as salicylic acid (SA) and jasmonic acid (JA). Because herbivore densities are dynamic in time, this may affect plant-mediated interactions between different herbivores attacking at the same time. In Arabidopsis thaliana, feeding by Brevicoryne brassicae aphids interferes with induced defenses against Plutella xylostella caterpillars. This is density dependent: at a low aphid density, the growth rate of P. xylostella was increased, whereas caterpillars feeding on plants colonized by aphids at a high density have a reduced growth rate. Growth of P. xylostella larvae was unaffected on sid2-1 or on dde2-2 mutant plants when feeding simultaneously with a low or high aphid density. This shows that aphid interference with caterpillar-induced defenses requires both SA and JA signal transduction pathways. Transcriptional analysis revealed that simultaneous feeding by caterpillars and aphids at a low density induced the expression of the SA transcription factor gene WRKY70 whereas expression of WRKY70 was lower in plants induced with both caterpillars and a high aphid density. Interestingly, the expression of the JA transcription factor gene MYC2 was significantly higher in plants simultaneously attacked by aphids at a high density and caterpillars. These results indicate that a lower expression level of WRKY70 leads to significantly higher MYC2 expression through SA-JA cross-talk. Thus, plant-mediated interactions between aphids and caterpillars are density dependent and involve phytohormonal cross-talk and differential activation of transcription factors.
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Affiliation(s)
- Anneke Kroes
- Laboratory of Entomology, Wageningen University, Radix building, Droevendaalsesteeg 1, 6708PB Wageningen, The Netherlands
| | - Joop J A van Loon
- Laboratory of Entomology, Wageningen University, Radix building, Droevendaalsesteeg 1, 6708PB Wageningen, The Netherlands
| | - Marcel Dicke
- Laboratory of Entomology, Wageningen University, Radix building, Droevendaalsesteeg 1, 6708PB Wageningen, The Netherlands
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Appel HM, Fescemyer H, Ehlting J, Weston D, Rehrig E, Joshi T, Xu D, Bohlmann J, Schultz J. Transcriptional responses of Arabidopsis thaliana to chewing and sucking insect herbivores. FRONTIERS IN PLANT SCIENCE 2014; 5:565. [PMID: 25452759 PMCID: PMC4231836 DOI: 10.3389/fpls.2014.00565] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Accepted: 10/01/2014] [Indexed: 05/22/2023]
Abstract
We tested the hypothesis that Arabidopsis can recognize and respond differentially to insect species at the transcriptional level using a genome wide microarray. Transcriptional reprogramming was characterized using co-expression analysis in damaged and undamaged leaves at two times in response to mechanical wounding and four insect species. In all, 2778 (10.6%) of annotated genes on the array were differentially expressed in at least one treatment. Responses differed mainly between aphid and caterpillar and sampling times. Responses to aphids and caterpillars shared only 10% of up-regulated and 8% of down-regulated genes. Responses to two caterpillars shared 21 and 12% of up- and down-regulated genes, whereas responses to the two aphids shared only 7 and 4% of up-regulated and down-regulated genes. Overlap in genes expressed between 6 and 24 h was 3-15%, and depended on the insect species. Responses in attacked and unattacked leaves differed at 6 h but converged by 24 h. Genes responding to the insects are also responsive to many stressors and included primary metabolism. Aphids down-regulated amino acid catabolism; caterpillars stimulated production of amino acids involved in glucosinolate synthesis. Co-expression analysis revealed 17 response networks. Transcription factors were a major portion of differentially expressed genes throughout and responsive genes shared most of the known or postulated binding sites. However, cis-element composition of genes down regulated by the aphid M. persicae was unique, as were those of genes down-regulated by caterpillars. As many as 20 cis-elements were over-represented in one or more treatments, including some from well-characterized classes and others as yet uncharacterized. We suggest that transcriptional changes elicited by wounding and insects are heavily influenced by transcription factors and involve both enrichment of a common set of cis-elements and a unique enrichment of a few cis-elements in responding genes.
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Affiliation(s)
- Heidi M. Appel
- Bond Life Sciences Center and Division of Plant Sciences, University of MissouriColumbia, MO, USA
| | - Howard Fescemyer
- Department of Biology, The Pennsylvania State UniversityUniversity Park, PA, USA
| | - Juergen Ehlting
- Michael Smith Laboratories, University of British ColumbiaVancouver, BC, Canada
- Department of Biology, University of VictoriaVictoria, BC, Canada
| | - David Weston
- Biosciences Division, Oak Ridge National LaboratoryOak Ridge, TN, USA
| | - Erin Rehrig
- Biology and Chemistry Department, Fitchburg State UniversityFitchburg, MA, USA
| | - Trupti Joshi
- Department of Computer Science, Bond Life Sciences Center, Informatics Institute, University of MissouriColumbia, MO, USA
| | - Dong Xu
- Department of Computer Science, Bond Life Sciences Center, Informatics Institute, University of MissouriColumbia, MO, USA
| | - Joerg Bohlmann
- Michael Smith Laboratories, University of British ColumbiaVancouver, BC, Canada
| | - Jack Schultz
- Bond Life Sciences Center and Division of Plant Sciences, University of MissouriColumbia, MO, USA
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Bosch M, Berger S, Schaller A, Stintzi A. Jasmonate-dependent induction of polyphenol oxidase activity in tomato foliage is important for defense against Spodoptera exigua but not against Manduca sexta. BMC PLANT BIOLOGY 2014; 14:257. [PMID: 25261073 PMCID: PMC4189532 DOI: 10.1186/s12870-014-0257-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 09/22/2014] [Indexed: 05/05/2023]
Abstract
BACKGROUND Jasmonates are involved in plant defense, participating in the timely induction of defense responses against insect herbivores from different feeding guilds and with different degrees of host specialization. It is less clear to what extent the induction of plant defense is controlled by different members of the jasmonate family and how specificity of the response is achieved. Using transgenic plants blocked in jasmonic acid (JA) biosynthesis, we previously showed that JA is required for the formation of glandular trichomes and trichome-borne metabolites as constitutive defense traits in tomato, affecting oviposition and feeding behavior of the specialist Manduca sexta. In contrast, JA was not required for the local induction of defense gene expression after wounding. In JA-deficient plants, the JA precursor oxophytodienoic acid (OPDA) substituted as a regulator of defense gene expression maintaining considerable resistance against M. sexta larvae. In this study, we investigate the contribution of JA and OPDA to defense against the generalist herbivore Spodoptera exigua. RESULTS S. exigua preferred JA-deficient over wild-type tomato plants as a host for both oviposition and feeding. Feeding preference for JA-deficient plants was caused by constitutively reduced levels of repellent terpenes. Growth and development of the larvae, on the other hand, were controlled by additional JA-dependent defense traits, including the JA-mediated induction of foliar polyphenol oxidase (PPO) activity. PPO induction was more pronounced after S. exigua herbivory as compared to mechanical wounding or M. sexta feeding. The difference was attributed to an elicitor exclusively present in S. exigua oral secretions. CONCLUSIONS The behavior of M. sexta and S. exigua during oviposition and feeding is controlled by constitutive JA/JA-Ile-dependent defense traits involving mono- and sesquiterpenes in both species, and cis-3-hexenal as an additional chemical cue for M. sexta. The requirement of jasmonates for resistance of tomato plants against caterpillar feeding differs for the two species. While the OPDA-mediated induction of local defense is sufficient to restrict growth and development of M. sexta larvae in absence of JA/JA-Ile, defense against S. exigua relied on additional JA/JA-Ile dependent factors, including the induction of foliar polyphenol oxidase activity in response to S. exigua oral secretions.
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Affiliation(s)
- Marko Bosch
- Institute of Plant Physiology and Biotechnology, University of Hohenheim (260), 70593 Stuttgart, Germany
| | - Sonja Berger
- Institute of Plant Physiology and Biotechnology, University of Hohenheim (260), 70593 Stuttgart, Germany
| | - Andreas Schaller
- Institute of Plant Physiology and Biotechnology, University of Hohenheim (260), 70593 Stuttgart, Germany
| | - Annick Stintzi
- Institute of Plant Physiology and Biotechnology, University of Hohenheim (260), 70593 Stuttgart, Germany
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Desurmont GA, Harvey J, van Dam NM, Cristescu SM, Schiestl FP, Cozzolino S, Anderson P, Larsson MC, Kindlmann P, Danner H, Turlings TCJ. Alien interference: disruption of infochemical networks by invasive insect herbivores. PLANT, CELL & ENVIRONMENT 2014; 37:1854-65. [PMID: 24689553 DOI: 10.1111/pce.12333] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 03/12/2014] [Accepted: 03/14/2014] [Indexed: 05/09/2023]
Abstract
Insect herbivores trigger various biochemical changes in plants, and as a consequence, affect other organisms that are associated with these plants. Such plant-mediated indirect effects often involve herbivore-induced plant volatiles (HIPVs) that can be used as cues for foraging herbivores and their natural enemies, and are also known to affect pollinator attraction. In tightly co-evolved systems, the different trophic levels are expected to display adaptive response to changes in HIPVs caused by native herbivores. But what if a new herbivore invades such a system? Current literature suggests that exotic herbivores have the potential to affect HIPV production, and that plant responses to novel herbivores are likely to depend on phylogenetic relatedness between the invader and the native species. Here we review the different ways exotic herbivores can disrupt chemically mediated interactions between plants and the key users of HIPVs: herbivores, pollinators, and members of the third (i.e. predators and parasitoids) and fourth (i.e. hyperparasitoids) trophic levels. Current theory on insect invasions needs to consider that disruptive effects of invaders on infochemical networks can have a short-term impact on the population dynamics of native insects and plants, as well as exerting potentially negative consequences for the functioning of native ecosystems.
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Affiliation(s)
- Gaylord A Desurmont
- Institute of Biology, University of Neuchâtel, CH-2000, Neuchâtel, Switzerland
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Lazebnik J, Frago E, Dicke M, van Loon JJA. Phytohormone Mediation of Interactions Between Herbivores and Plant Pathogens. J Chem Ecol 2014; 40:730-41. [DOI: 10.1007/s10886-014-0480-7] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 07/03/2014] [Accepted: 07/07/2014] [Indexed: 08/29/2023]
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Campos ML, Kang JH, Howe GA. Jasmonate-triggered plant immunity. J Chem Ecol 2014; 40:657-75. [PMID: 24973116 DOI: 10.1007/s10886-014-0468-3] [Citation(s) in RCA: 198] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 06/06/2014] [Accepted: 06/17/2014] [Indexed: 11/29/2022]
Abstract
The plant hormone jasmonate (JA) exerts direct control over the production of chemical defense compounds that confer resistance to a remarkable spectrum of plant-associated organisms, ranging from microbial pathogens to vertebrate herbivores. The underlying mechanism of JA-triggered immunity (JATI) can be conceptualized as a multi-stage signal transduction cascade involving: i) pattern recognition receptors (PRRs) that couple the perception of danger signals to rapid synthesis of bioactive JA; ii) an evolutionarily conserved JA signaling module that links fluctuating JA levels to changes in the abundance of transcriptional repressor proteins; and iii) activation (de-repression) of transcription factors that orchestrate the expression of myriad chemical and morphological defense traits. Multiple negative feedback loops act in concert to restrain the duration and amplitude of defense responses, presumably to mitigate potential fitness costs of JATI. The convergence of diverse plant- and non-plant-derived signals on the core JA module indicates that JATI is a general response to perceived danger. However, the modular structure of JATI may accommodate attacker-specific defense responses through evolutionary innovation of PRRs (inputs) and defense traits (outputs). The efficacy of JATI as a defense strategy is highlighted by its capacity to shape natural populations of plant attackers, as well as the propensity of plant-associated organisms to subvert or otherwise manipulate JA signaling. As both a cellular hub for integrating informational cues from the environment and a common target of pathogen effectors, the core JA module provides a focal point for understanding immune system networks and the evolution of chemical diversity in the plant kingdom.
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Affiliation(s)
- Marcelo L Campos
- Department of Energy-Plant Research Laboratory, Michigan State University, East Lansing, MI, 48824, USA
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48
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Onkokesung N, Reichelt M, van Doorn A, Schuurink RC, van Loon JJ, Dicke M. Modulation of flavonoid metabolites in Arabidopsis thaliana through overexpression of the MYB75 transcription factor: role of kaempferol-3,7-dirhamnoside in resistance to the specialist insect herbivore Pieris brassicae. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:2203-17. [PMID: 24619996 PMCID: PMC3991749 DOI: 10.1093/jxb/eru096] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Anthocyanins and flavonols are secondary metabolites that can function in plant defence against herbivores. In Arabidopsis thaliana, anthocyanin and flavonol biosynthesis are regulated by MYB transcription factors. Overexpression of MYB75 (oxMYB75) in Arabidopsis results in increasing anthocyanin and flavonol levels which enhances plant resistance to generalist caterpillars. However, how these metabolites affect specialist herbivores has remained unknown. Performance of a specialist aphid (Brevicoryne brassicae) was unaffected after feeding on oxMYB75 plants, whereas a specialist caterpillar (Pieris brassicae) gained significantly higher body mass when feeding on this plant. An increase in anthocyanin and total flavonol glycoside levels correlated negatively with the body mass of caterpillars fed on oxMYB75 plants. However, a significant reduction of kaempferol-3,7-dirhamnoside (KRR) corresponded to an increased susceptibility of oxMYB75 plants to caterpillar feeding. Pieris brassicae caterpillars also grew less on an artificial diet containing KRR or on oxMYB75 plants that were exogenously treated with KRR, supporting KRR's function in direct defence against this specialist caterpillar. The results show that enhancing the activity of the anthocyanin pathway in oxMYB75 plants results in re-channelling of quercetin/kaempferol metabolites which has a negative effect on the accumulation of KRR, a novel defensive metabolite against a specialist caterpillar.
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Affiliation(s)
- Nawaporn Onkokesung
- Laboratory of Entomology, Wageningen University, PO Box 8031, 6700EH Wageningen, The Netherlands
| | - Michael Reichelt
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll Straβe 8, D-07745 Jena, Germany
| | - Arjen van Doorn
- Keygene NV, Agro Business Park 90, 6708OW, Wageningen, The Netherlands
| | - Robert C. Schuurink
- Plant Physiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098XH Amsterdam, The Netherlands
| | - Joop J.A. van Loon
- Laboratory of Entomology, Wageningen University, PO Box 8031, 6700EH Wageningen, The Netherlands
| | - Marcel Dicke
- Laboratory of Entomology, Wageningen University, PO Box 8031, 6700EH Wageningen, The Netherlands
- * To whom correspondence should be addressed. E-mail:
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Ali JG, Agrawal AA. Asymmetry of plant-mediated interactions between specialist aphids and caterpillars on two milkweeds. Funct Ecol 2014. [DOI: 10.1111/1365-2435.12271] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jared G. Ali
- Department of Entomology; Michigan State University; East Lansing Michigan 48824 USA
| | - Anurag A. Agrawal
- Department of Ecology & Evolutionary Biology; Cornell University; Ithaca New York 14853 USA
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Kliebenstein DJ. Orchestration of plant defense systems: genes to populations. TRENDS IN PLANT SCIENCE 2014; 19:250-255. [PMID: 24486317 DOI: 10.1016/j.tplants.2014.01.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 11/21/2013] [Accepted: 01/08/2014] [Indexed: 06/03/2023]
Abstract
Research over the past decades has made immense progress in identifying some genes and mechanisms underlying plant defense against biotic organisms. The recent movement towards systems biology approaches has increased mechanistic knowledge, revealing a need for understanding how all the genes and mechanisms integrate to create a response to any given biotic interaction. This begins with evidence that diverse molecular patterns converge, suggesting that the plant perceives signals not the interacting species. These signals then coordinate across regulatory networks via molecular interactions and cause non-cell autonomous responses in neighboring and systemic cells. Finally, the identification of transporters is showing that plant defenses are harmonized across tissues and even show the potential for coordination across individuals within a population.
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Affiliation(s)
- Daniel J Kliebenstein
- Department of Plant Sciences, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA; DynaMo Center of Excellence, University of Copenhagen, Thorvaldsensvej 40, DK-1871, Frederiksberg C, Denmark.
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