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Pastierovič F, Kalyniukova A, Hradecký J, Dvořák O, Vítámvás J, Mogilicherla K, Tomášková I. Biochemical Responses in Populus tremula: Defending against Sucking and Leaf-Chewing Insect Herbivores. PLANTS (BASEL, SWITZERLAND) 2024; 13:1243. [PMID: 38732458 PMCID: PMC11085190 DOI: 10.3390/plants13091243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 04/24/2024] [Accepted: 04/26/2024] [Indexed: 05/13/2024]
Abstract
The main biochemical traits were estimated in poplar leaves under biotic attack (aphids and spongy moth infestation). Changes in the abundance of bioactive compounds in genetically uniform individuals of European aspen (Populus tremula), such as proline, polyphenolic compounds, chlorophylls a and b, and volatile compounds, were determined between leaves damaged by sucking insects (aphid-Chaitophorus nassonowi) and chewing insects (spongy moth-Lymantria dispar) compared to uninfected leaves. Among the nine analyzed phenolic compounds, only catechin and procyanidin showed significant differences between the control leaves and leaves affected by spongy moths or aphids. GC-TOF-MS volatile metabolome analysis showed the clear separation of the control versus aphids-infested and moth-infested leaves. In total, the compounds that proved to have the highest explanatory power for aphid-infested leaves were 3-hexenal and 5-methyl-2-furanone, and for moth-infested leaves, trans-α-farnesene and 4-cyanocyclohexane. The aphid-infested leaves contained around half the amount of chlorophylls and twice the amount of proline compared to uninfected leaves, and these results evidenced that aphids influence plant physiology more than chewing insects.
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Affiliation(s)
- Filip Pastierovič
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Suchdol, 165 00 Praha, Czech Republic; (A.K.); (J.H.); (O.D.); (J.V.); or (K.M.); (I.T.)
| | - Alina Kalyniukova
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Suchdol, 165 00 Praha, Czech Republic; (A.K.); (J.H.); (O.D.); (J.V.); or (K.M.); (I.T.)
| | - Jaromír Hradecký
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Suchdol, 165 00 Praha, Czech Republic; (A.K.); (J.H.); (O.D.); (J.V.); or (K.M.); (I.T.)
| | - Ondřej Dvořák
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Suchdol, 165 00 Praha, Czech Republic; (A.K.); (J.H.); (O.D.); (J.V.); or (K.M.); (I.T.)
| | - Jan Vítámvás
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Suchdol, 165 00 Praha, Czech Republic; (A.K.); (J.H.); (O.D.); (J.V.); or (K.M.); (I.T.)
| | - Kanakachari Mogilicherla
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Suchdol, 165 00 Praha, Czech Republic; (A.K.); (J.H.); (O.D.); (J.V.); or (K.M.); (I.T.)
- ICAR-Indian Institute of Rice Research (IIRR), Rajendra Nagar, Hyderabad 500030, Telangana, India
| | - Ivana Tomášková
- Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Suchdol, 165 00 Praha, Czech Republic; (A.K.); (J.H.); (O.D.); (J.V.); or (K.M.); (I.T.)
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Skovmand L, O'Dea RE, Greig KA, Amato KR, Hendry AP. Effects of leaf herbivory and autumn seasonality on plant secondary metabolites: A meta-analysis. Ecol Evol 2024; 14:e10912. [PMID: 38357594 PMCID: PMC10864732 DOI: 10.1002/ece3.10912] [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: 02/16/2023] [Revised: 12/22/2023] [Accepted: 01/09/2024] [Indexed: 02/16/2024] Open
Abstract
Plant secondary metabolites (PSMs) are produced by plants to overcome environmental challenges, both biotic and abiotic. We were interested in characterizing how autumn seasonality in temperate and subtropical climates affects overall PSM production in comparison to herbivory. Herbivory is commonly measured between spring to summer when plants have high resource availability and prioritize growth and reproduction. However, autumn seasonality also challenges plants as they cope with limited resources and prepare survival for winter. This suggests a potential gap in our understanding of how herbivory affects PSM production in autumn compared to spring/summer. Using meta-analysis, we recorded overall production of 22 different PSM subgroups from 58 published papers to calculate effect sizes from herbivory studies (absence to presence) and temperate to subtropical seasonal studies (summer to autumn), while considering other variables (e.g., plant type, increase in time since herbivory, temperature, and precipitation). We also compared production of five phenolic PSM subgroups - hydroxybenzoic acids, flavan-3-ols, flavonols, hydrolysable tannins, and condensed tannins. We wanted to detect a shared response across all PSMs and found that herbivory increased overall PSM production in herbaceous plants. Herbivory was also found to have a positive effect on individual PSM subgroups, such as flavonol production, while autumn seasonality was found to have a positive effect on flavan-3-ol and condensed tannin production. We discuss how these responses might stem from plants producing some PSMs constitutively, whereas others are induced only after herbivory, and how plants produce metabolites with higher costs only during seasons when other resources for growth and reproduction are less available, while other phenolic PSM subgroups serve more than one function for plants and such functions can be season dependent. The outcome of our meta-analysis is that autumn seasonality changes some PSM production differently from herbivory, and we see value in further investigating seasonality-herbivory interactions with plant chemical defense.
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Affiliation(s)
- Lota Skovmand
- Redpath Museum & Department of BiologyMcGill UniversityMontrealQuebecCanada
| | - Rose E. O'Dea
- School of Agriculture, Food, and Ecosystem SciencesUniversity of MelbourneMelbourneVictoriaAustralia
| | - Keri A. Greig
- Department of Integrative BiologyUniversity of Texas at AustinAustinTexasUSA
| | | | - Andrew P. Hendry
- Redpath Museum & Department of BiologyMcGill UniversityMontrealQuebecCanada
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Yánez-Segovia S, Ramírez CC, Lindroth RL, Fuentes-Contreras E. Resistance against Leucoptera sinuella (Lepidoptera: Lyonetiidae) among hybrid clones of Populus spp. in central Chile. JOURNAL OF ECONOMIC ENTOMOLOGY 2023; 116:1662-1670. [PMID: 37441732 DOI: 10.1093/jee/toad129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 05/18/2023] [Accepted: 06/22/2023] [Indexed: 07/15/2023]
Abstract
Leucoptera sinuella (Reutti) (Lepidoptera: Lyonetiidae) is a leaf miner specialist on Salicaceae recently introduced to Chile and Argentina, where it is causing economic damage to poplar plantations. We report a field survey in a poplar nursery naturally infested showing that regardless of the poplar hybrid taxon, high variability in resistance was observed among clones within families for oviposition and leaf-mining damage. A group of susceptible and resistant hybrid poplar clones was then selected for a laboratory evaluation of oviposition (antixenosis) and leaf-mining damage (antibiosis) on potted, rooted shoot cuttings. The concentration of condensed tannins (CTs) and salicinoid phenolic glucosides (SPGs) of the leaves of the selected clones from the laboratory study was also measured. Total oviposited eggs were positively correlated with leaf area, with the lowest oviposition on TMxT 11372 clone. The lowest percentage of mined leaf area was obtained for clones TMxT 11372, TMxT 11463, and TDxD 17574, but surprisingly no correlation between the percentage of mined leaf area and concentration of CTs and SPGs was found. Resistant poplar hybrids of our study could be suitable for breeding programs aimed for L. sinuella integrated pest management.
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Affiliation(s)
- Sebastián Yánez-Segovia
- Centro de Ecología Molecular y Funcional (CEMF), Facultad de Ciencias Agrarias, Universidad de Talca, Casilla 747, Talca, Chile
| | - Claudio C Ramírez
- Centro de Ecología Molecular y Funcional (CEMF), Instituto de Ciencias Biológicas, Universidad de Talca, Casilla 747, Talca, Chile
| | - Richard L Lindroth
- Department of Entomology, University of Wisconsin-Madison, 237 Russell Laboratories, 1630 Linden Drive, Madison, WI 53706, USA
| | - Eduardo Fuentes-Contreras
- Centro de Ecología Molecular y Funcional (CEMF), Facultad de Ciencias Agrarias, Universidad de Talca, Casilla 747, Talca, Chile
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Dávila C, Fiorenza JE, Gershenzon J, Reichelt M, Zavala JA, Fernández PC. Sawfly egg deposition extends the insect life cycle and alters hormone and volatile emission profiles. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.1084063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
IntroductionInsect oviposition can enhance plant defenses and decrease plant quality in response to future feeding damage by hatched larvae. Induced resistance triggered by egg deposition and its negative effect on insect herbivore performance is known for several annual plants but has been much less studied in woody perennials, such as species of the Salicaceae. Here we studied the response of the willow Salix babylonica to oviposition by the specialist willow sawfly Nematus oligospilus and its impact on insect performance.MethodsWe measured the effect of oviposition on larval feeding and pupa formation and evaluated its influence on plant phytohormones and volatile emission profile.ResultsWe showed that oviposition reduced neonate larval growth and increased the proportion of prepupae that delayed their transition to pupae, thus extending the length of the sawfly cocoon phase. Oviposited willows increased jasmonic acid levels and changed their volatile profile through enhanced concentrations of the terpenoids, (E/E)-α-farnesene, (Z)- and (E)-β-ocimene. Volatile profiles were characteristic for each type of insect damage (oviposition vs. feeding), but no priming effect was found.DiscussionWe demonstrated that willows could perceive sawfly oviposition per se as a primary factor activating defense signaling via the jasmonic acid pathway. This induced response ultimately determined changes in pupation dynamics that may affect the whole insect population cycle.
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Gordon H, Fellenberg C, Lackus ND, Archinuk F, Sproule A, Nakamura Y, K�llner TG, Gershenzon J, Overy DP, Constabel CP. CRISPR/Cas9 disruption of UGT71L1 in poplar connects salicinoid and salicylic acid metabolism and alters growth and morphology. THE PLANT CELL 2022; 34:2925-2947. [PMID: 35532172 PMCID: PMC9338807 DOI: 10.1093/plcell/koac135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 04/28/2022] [Indexed: 05/11/2023]
Abstract
Salicinoids are salicyl alcohol-containing phenolic glycosides with strong antiherbivore effects found only in poplars and willows. Their biosynthesis is poorly understood, but recently a UDP-dependent glycosyltransferase, UGT71L1, was shown to be required for salicinoid biosynthesis in poplar tissue cultures. UGT71L1 specifically glycosylates salicyl benzoate, a proposed salicinoid intermediate. Here, we analyzed transgenic CRISPR/Cas9-generated UGT71L1 knockout plants. Metabolomic analyses revealed substantial reductions in the major salicinoids, confirming the central role of the enzyme in salicinoid biosynthesis. Correspondingly, UGT71L1 knockouts were preferred to wild-type by white-marked tussock moth (Orgyia leucostigma) larvae in bioassays. Greenhouse-grown knockout plants showed substantial growth alterations, with decreased internode length and smaller serrated leaves. Reinserting a functional UGT71L1 gene in a transgenic rescue experiment demonstrated that these effects were due only to the loss of UGT71L1. The knockouts contained elevated salicylate (SA) and jasmonate (JA) concentrations, and also had enhanced expression of SA- and JA-related genes. SA is predicted to be released by UGT71L1 disruption, if salicyl salicylate is a pathway intermediate and UGT71L1 substrate. This idea was supported by showing that salicyl salicylate can be glucosylated by recombinant UGT71L1, providing a potential link of salicinoid metabolism to SA and growth impacts. Connecting this pathway with growth could imply that salicinoids are under additional evolutionary constraints beyond selective pressure by herbivores.
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Affiliation(s)
- Harley Gordon
- Department of Biology, Centre for Forest Biology, University of Victoria, Victoria, BC V8P 5C2, Canada
| | - Christin Fellenberg
- Department of Biology, Centre for Forest Biology, University of Victoria, Victoria, BC V8P 5C2, Canada
| | - Nathalie D Lackus
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena 07745, Germany
| | - Finn Archinuk
- Department of Biology, Centre for Forest Biology, University of Victoria, Victoria, BC V8P 5C2, Canada
| | - Amanda Sproule
- Agriculture and Agri-Food Canada, Ottawa, Ontario K1A 0C6, Canada
| | - Yoko Nakamura
- Department of Nuclear Magnetic Resonance, Max Planck Institute for Chemical Ecology, Jena 07745, Germany
- Department of Natural Product Biosynthesis, Max Planck Institute for Chemical Ecology, Jena 07745, Germany
| | - Tobias G K�llner
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena 07745, Germany
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena 07745, Germany
| | - David P Overy
- Agriculture and Agri-Food Canada, Ottawa, Ontario K1A 0C6, Canada
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Volf M, Volfová T, Seifert CL, Ludwig A, Engelmann RA, Jorge LR, Richter R, Schedl A, Weinhold A, Wirth C, van Dam NM. A mosaic of induced and non-induced branches promotes variation in leaf traits, predation and insect herbivore assemblages in canopy trees. Ecol Lett 2021; 25:729-739. [PMID: 34958165 DOI: 10.1111/ele.13943] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/10/2021] [Accepted: 11/24/2021] [Indexed: 12/12/2022]
Abstract
Forest canopies are complex and highly diverse environments. Their diversity is affected by pronounced gradients in abiotic and biotic conditions, including variation in leaf chemistry. We hypothesised that branch-localised defence induction and vertical stratification in mature oaks constitute sources of chemical variation that extend across trophic levels. To test this, we combined manipulation of plant defences, predation monitoring, food-choice trials with herbivores and sampling of herbivore assemblages. Both induction and vertical stratification affected branch chemistry, but the effect of induction was stronger. Induction increased predation in the canopy and reduced herbivory in bioassays. The effects of increased predation affected herbivore assemblages by decreasing their abundance, and indirectly, their richness. In turn, we show that there are multiple factors contributing to variation across canopies. Branch-localised induction, variation between tree individuals and predation may be the ones with particularly strong effects on diverse assemblages of insects in temperate forests.
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Affiliation(s)
- Martin Volf
- Institute of Entomology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic.,German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Tereza Volfová
- Institute of Entomology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic.,Faculty of Science, University of South Bohemia, Ceske Budejovice, Czech Republic
| | - Carlo L Seifert
- Institute of Entomology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic.,Faculty of Science, University of South Bohemia, Ceske Budejovice, Czech Republic.,Faculty of Forest Sciences and Forest Ecology, Department of Forest Nature Conservation, Georg-August-University, Göttingen, Germany
| | - Antonia Ludwig
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany.,Institute for Biology, University of Leipzig, Leipzig, Germany
| | - Rolf A Engelmann
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany.,Institute for Biology, University of Leipzig, Leipzig, Germany
| | - Leonardo Ré Jorge
- Institute of Entomology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic
| | - Ronny Richter
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany.,Institute for Biology, University of Leipzig, Leipzig, Germany.,Geoinformatics and Remote Sensing, Institute for Geography, University of Leipzig, Leipzig, Germany
| | - Andreas Schedl
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany.,Institute of Biodiversity, Friedrich Schiller University Jena, Jena, Germany
| | - Alexander Weinhold
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany.,Institute of Biodiversity, Friedrich Schiller University Jena, Jena, Germany
| | - Christian Wirth
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany.,Institute for Biology, University of Leipzig, Leipzig, Germany.,Max-Planck Institute for Biogeochemistry, Jena, Germany
| | - Nicole M van Dam
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany.,Institute of Biodiversity, Friedrich Schiller University Jena, Jena, Germany
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Proanthocyanidins and Where to Find Them: A Meta-Analytic Approach to Investigate Their Chemistry, Biosynthesis, Distribution, and Effect on Human Health. Antioxidants (Basel) 2021; 10:antiox10081229. [PMID: 34439477 PMCID: PMC8389005 DOI: 10.3390/antiox10081229] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/26/2021] [Accepted: 07/27/2021] [Indexed: 12/22/2022] Open
Abstract
Proanthocyanidins (PACs) are a class of polyphenolic compounds that are attracting considerable interest in the nutraceutical field due to their potential health benefits. However, knowledge about the chemistry, biosynthesis, and distribution of PACs is limited. This review summarizes the main chemical characteristics and biosynthetic pathways and the main analytical methods aimed at their identification and quantification in raw plant matrices. Furthermore, meta-analytic approaches were used to identify the main plant sources in which PACs were contained and to investigate their potential effect on human health. In particular, a cluster analysis identified PACs in 35 different plant families and 60 different plant parts normally consumed in the human diet. On the other hand, a literature search, coupled with forest plot analyses, highlighted how PACs can be actively involved in both local and systemic effects. Finally, the potential mechanisms of action through which PACs may impact human health were investigated, focusing on their systemic hypoglycemic and lipid-lowering effects and their local anti-inflammatory actions on the intestinal epithelium. Overall, this review may be considered a complete report in which chemical, biosynthetic, ecological, and pharmacological aspects of PACs are discussed.
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Lackus ND, Schmidt A, Gershenzon J, Köllner TG. A peroxisomal β-oxidative pathway contributes to the formation of C6-C1 aromatic volatiles in poplar. PLANT PHYSIOLOGY 2021; 186:891-909. [PMID: 33723573 PMCID: PMC8195509 DOI: 10.1093/plphys/kiab111] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 02/19/2021] [Indexed: 05/06/2023]
Abstract
Benzenoids (C6-C1 aromatic compounds) play important roles in plant defense and are often produced upon herbivory. Black cottonwood (Populus trichocarpa) produces a variety of volatile and nonvolatile benzenoids involved in various defense responses. However, their biosynthesis in poplar is mainly unresolved. We showed feeding of the poplar leaf beetle (Chrysomela populi) on P. trichocarpa leaves led to increased emission of the benzenoid volatiles benzaldehyde, benzylalcohol, and benzyl benzoate. The accumulation of salicinoids, a group of nonvolatile phenolic defense glycosides composed in part of benzenoid units, was hardly affected by beetle herbivory. In planta labeling experiments revealed that volatile and nonvolatile poplar benzenoids are produced from cinnamic acid (C6-C3). The biosynthesis of C6-C1 aromatic compounds from cinnamic acid has been described in petunia (Petunia hybrida) flowers where the pathway includes a peroxisomal-localized chain shortening sequence, involving cinnamate-CoA ligase (CNL), cinnamoyl-CoA hydratase/dehydrogenase (CHD), and 3-ketoacyl-CoA thiolase (KAT). Sequence and phylogenetic analysis enabled the identification of small CNL, CHD, and KAT gene families in P. trichocarpa. Heterologous expression of the candidate genes in Escherichia coli and characterization of purified proteins in vitro revealed enzymatic activities similar to those described in petunia flowers. RNA interference-mediated knockdown of the CNL subfamily in gray poplar (Populus x canescens) resulted in decreased emission of C6-C1 aromatic volatiles upon herbivory, while constitutively accumulating salicinoids were not affected. This indicates the peroxisomal β-oxidative pathway participates in the formation of volatile benzenoids. The chain shortening steps for salicinoids, however, likely employ an alternative pathway.
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Affiliation(s)
- Nathalie D Lackus
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
| | - Axel Schmidt
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
| | - Tobias G Köllner
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, D-07745 Jena, Germany
- Author for communication:
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Cole CT, Morrow CJ, Barker HL, Rubert-Nason KF, Riehl JFL, Köllner TG, Lackus ND, Lindroth RL. Growing up aspen: ontogeny and trade-offs shape growth, defence and reproduction in a foundation species. ANNALS OF BOTANY 2021; 127:505-517. [PMID: 32296821 PMCID: PMC7988516 DOI: 10.1093/aob/mcaa070] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 04/13/2020] [Indexed: 05/04/2023]
Abstract
BACKGROUND AND AIMS Intraspecific variation in foundation species of forest ecosystems can shape community and ecosystem properties, particularly when that variation has a genetic basis. Traits mediating interactions with other species are predicted by simple allocation models to follow ontogenetic patterns that are rarely studied in trees. The aim of this research was to identify the roles of genotype, ontogeny and genotypic trade-offs shaping growth, defence and reproduction in aspen. METHODS We established a common garden replicating >500 aspen genets in Wisconsin, USA. Trees were measured through the juvenile period into the onset of reproduction, for growth, defence chemistry (phenolic glycosides and condensed tannins), nitrogen, extrafloral nectaries, leaf morphology (specific leaf area), flower production and foliar herbivory and disease. We also assayed the TOZ19 sex marker and heterozygosity at ten microsatellite loci. KEY RESULTS We found high levels of genotypic variation for all traits, and high heritabilities for both the traits and their ontogenetic trajectories. Ontogeny strongly shaped intraspecific variation, and trade-offs among growth, defence and reproduction supported some predictions while contradicting others. Both direct resistance (chemical defence) and indirect defence (extrafloral nectaries) declined during the juvenile stage, prior to the onset of reproduction. Reproduction was higher in trees that were larger, male and had higher individual heterozygosity. Growth was diminished by genotypic allocation to both direct and indirect defence as well as to reproduction, but we found no evidence of trade-offs between defence and reproduction. CONCLUSIONS Key traits affecting the ecological communities of aspen have high levels of genotypic variation and heritability, strong patterns of ontogeny and clear trade-offs among growth, defence and reproduction. The architecture of aspen's community genetics - its ontogeny, trade-offs and especially its great variability - is shaped by both its broad range and the diverse community of associates, and in turn further fosters that diversity.
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Affiliation(s)
- Christopher T Cole
- Department of Entomology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI, USA
| | - Clay J Morrow
- Department of Entomology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI, USA
| | - Hilary L Barker
- Department of Entomology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI, USA
| | - Kennedy F Rubert-Nason
- Department of Entomology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI, USA
- Department of Natural and Behavioral Sciences, University of Maine at Ft. Kent, 23 University Drive, Fort Kent, ME, USA
| | - Jennifer F L Riehl
- Department of Entomology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI, USA
| | - Tobias G Köllner
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Strasse 8, Jena, Germany
| | - Nathalie D Lackus
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Strasse 8, Jena, Germany
| | - Richard L Lindroth
- Department of Entomology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI, USA
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Thakur MP, Künne T, Unsicker SB, Biere A, Ferlian O, Pruschitzki U, Thouvenot L, Türke M, Eisenhauer N. Invasive earthworms reduce chemical defense and increase herbivory and pathogen infection in native trees. THE JOURNAL OF ECOLOGY 2021; 109:763-775. [PMID: 33664527 PMCID: PMC7891629 DOI: 10.1111/1365-2745.13504] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 09/01/2020] [Indexed: 05/24/2023]
Abstract
Recent research shows that earthworms can alter defense traits of plants against herbivores and pathogens by affecting soil biochemistry. Yet, the effects of invasive earthworms on defense traits of native plants from previously earthworm-free ecosystems as well as the consequences for multitrophic interactions are virtually unknown.Here we use a combination of an observational study and a complementary experimental study to investigate the effects of invasive earthworms on leaf defense traits, herbivore damage and pathogen infection in two poplar tree species (Populus balsamifera and Populus tremuloides) native to North American boreal forests.Our observational study showed that earthworm invasion was associated with enhanced leaf herbivory (by leaf-chewing insects) in saplings of both tree species. However, we only detected significant shifts in the concentration of chemical defense compounds in response to earthworm invasion for P. balsamifera. Specifically, leaf phenolic concentrations, including salicinoids and catechin, were lower in P. balsamifera from earthworm-invaded sites.Our experimental study confirmed an earthworm-induced reduction in leaf defense levels in P. balsamifera for one of the defense compounds, tremulacin. The experimental study additionally showed that invasive earthworms reduced leaf dry matter content, potentially increasing leaf palatability, and enhanced susceptibility of trees to infection by a fungal pathogen, but not to aphid infestation, in the same tree species. Synthesis. Our results show that invasive earthworms can decrease the concentrations of some chemical defense compounds in P. balsamifera, which could make them susceptible to leaf-chewing insects. Such potential impacts of invasive earthworms are likely to have implications for tree survival and competition, native tree biodiversity and ecosystem functioning.
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Affiliation(s)
- Madhav P. Thakur
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐LeipzigLeipzigGermany
- Institute of BiologyLeipzig UniversityLeipzigGermany
- Department of Terrestrial EcologyNetherlands Institute of Ecology (NIOO‐KNAW)WageningenThe Netherlands
- Terrestrial Ecology GroupInstitute of Ecology and EvolutionUniversity of BernBernSwitzerland
| | - Tom Künne
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐LeipzigLeipzigGermany
| | - Sybille B. Unsicker
- Department of BiochemistryMax Planck Institute for Chemical EcologyJenaGermany
| | - Arjen Biere
- Department of Terrestrial EcologyNetherlands Institute of Ecology (NIOO‐KNAW)WageningenThe Netherlands
| | - Olga Ferlian
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐LeipzigLeipzigGermany
- Institute of BiologyLeipzig UniversityLeipzigGermany
| | - Ulrich Pruschitzki
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐LeipzigLeipzigGermany
- Institute of BiologyLeipzig UniversityLeipzigGermany
| | - Lise Thouvenot
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐LeipzigLeipzigGermany
- Institute of BiologyLeipzig UniversityLeipzigGermany
| | - Manfred Türke
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐LeipzigLeipzigGermany
- Institute of BiologyLeipzig UniversityLeipzigGermany
| | - Nico Eisenhauer
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐LeipzigLeipzigGermany
- Institute of BiologyLeipzig UniversityLeipzigGermany
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11
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Lackus ND, Morawetz J, Xu H, Gershenzon J, Dickschat JS, Köllner TG. The Sesquiterpene Synthase PtTPS5 Produces (1 S,5 S,7 R,10 R)-Guaia-4(15)-en-11-ol and (1 S,7 R,10 R)-Guaia-4-en-11-ol in Oomycete-Infected Poplar Roots. Molecules 2021; 26:555. [PMID: 33494506 PMCID: PMC7866031 DOI: 10.3390/molecules26030555] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/17/2021] [Accepted: 01/19/2021] [Indexed: 01/15/2023] Open
Abstract
Pathogen infection often leads to the enhanced formation of specialized plant metabolites that act as defensive barriers against microbial attackers. In this study, we investigated the formation of potential defense compounds in roots of the Western balsam poplar (Populus trichocarpa) upon infection with the generalist root pathogen Phytophthora cactorum (Oomycetes). P. cactorum infection led to an induced accumulation of terpenes, aromatic compounds, and fatty acids in poplar roots. Transcriptome analysis of uninfected and P. cactorum-infected roots revealed a terpene synthase gene PtTPS5 that was significantly induced upon pathogen infection. PtTPS5 had been previously reported as a sesquiterpene synthase producing two unidentified sesquiterpene alcohols as major products and hedycaryol as a minor product. Using heterologous expression in Escherichia coli, enzyme assays with deuterium-labeled substrates, and NMR analysis of reaction products, we could identify the major PtTPS5 products as (1S,5S,7R,10R)-guaia-4(15)-en-11-ol and (1S,7R,10R)-guaia-4-en-11-ol, with the former being a novel compound. The transcript accumulation of PtTPS5 in uninfected and P. cactorum-infected poplar roots matched the accumulation of (1S,5S,7R,10R)-guaia-4(15)-en-11-ol, (1S,7R,10R)-guaia-4-en-11-ol, and hedycaryol in this tissue, suggesting that PtTPS5 likely contributes to the pathogen-induced formation of these compounds in planta.
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Affiliation(s)
- Nathalie D. Lackus
- Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany; (N.D.L.); (J.M.); (J.G.)
| | - Jennifer Morawetz
- Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany; (N.D.L.); (J.M.); (J.G.)
| | - Houchao Xu
- Kekulé-Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany; (H.X.); (J.S.D.)
| | - Jonathan Gershenzon
- Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany; (N.D.L.); (J.M.); (J.G.)
| | - Jeroen S. Dickschat
- Kekulé-Institute of Organic Chemistry and Biochemistry, University of Bonn, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany; (H.X.); (J.S.D.)
| | - Tobias G. Köllner
- Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany; (N.D.L.); (J.M.); (J.G.)
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12
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Advances in Biosynthesis and Biological Functions of Proanthocyanidins in Horticultural Plants. Foods 2020; 9:foods9121774. [PMID: 33265960 PMCID: PMC7759826 DOI: 10.3390/foods9121774] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/26/2020] [Accepted: 11/26/2020] [Indexed: 02/06/2023] Open
Abstract
Proanthocyanidins are colorless flavonoid polymers condensed from flavan-3-ol units. They are essential secondary plant metabolites that contribute to the nutritional value and sensory quality of many fruits and the related processed products. Mounting evidence has shown that the accumulation of proanthocyanidins is associated with the resistance of plants against a broad spectrum of abiotic and biotic stress conditions. The biosynthesis of proanthocyanidins has been examined extensively, allowing for identifying and characterizing the key regulators controlling the biosynthetic pathway in many plants. New findings revealed that these specific regulators were involved in the proanthocyanidins biosynthetic network in response to various environmental conditions. This paper reviews the current knowledge regarding the control of key regulators in the underlying proanthocyanidins biosynthetic and molecular mechanisms in response to environmental stress. Furthermore, it discusses the directions for future research on the metabolic engineering of proanthocyanidins production to improve food and fruit crop quality.
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13
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Eberl F, Fernandez de Bobadilla M, Reichelt M, Hammerbacher A, Gershenzon J, Unsicker SB. Herbivory meets fungivory: insect herbivores feed on plant pathogenic fungi for their own benefit. Ecol Lett 2020; 23:1073-1084. [PMID: 32307873 DOI: 10.1111/ele.13506] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 01/19/2020] [Accepted: 03/08/2020] [Indexed: 12/23/2022]
Abstract
Plants are regularly colonised by fungi and bacteria, but plant-inhabiting microbes are rarely considered in studies on plant-herbivore interactions. Here we show that young gypsy moth (Lymantria dispar) caterpillars prefer to feed on black poplar (Populus nigra) foliage infected by the rust fungus Melampsora larici-populina instead of uninfected control foliage, and selectively consume fungal spores. This consumption, also observed in a related lepidopteran species, is stimulated by the sugar alcohol mannitol, found in much higher concentration in fungal tissue and infected leaves than uninfected plant foliage. Gypsy moth larvae developed more rapidly on rust-infected leaves, which cannot be attributed to mannitol but rather to greater levels of total nitrogen, essential amino acids and B vitamins in fungal tissue and fungus-infected leaves. Herbivore consumption of fungi and other microbes may be much more widespread than commonly believed with important consequences for the ecology and evolution of plant-herbivore interactions.
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Affiliation(s)
- Franziska Eberl
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745, Jena, Germany
| | - Maite Fernandez de Bobadilla
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745, Jena, Germany
| | - Michael Reichelt
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745, Jena, Germany
| | - Almuth Hammerbacher
- Department of Zoology and Entomology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private bag X20, Hatfield, 0028, South Africa
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745, Jena, Germany
| | - Sybille B Unsicker
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745, Jena, Germany
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14
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Fellenberg C, Corea O, Yan LH, Archinuk F, Piirtola EM, Gordon H, Reichelt M, Brandt W, Wulff J, Ehlting J, Peter Constabel C. Discovery of salicyl benzoate UDP-glycosyltransferase, a central enzyme in poplar salicinoid phenolic glycoside biosynthesis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 102:99-115. [PMID: 31736216 DOI: 10.1111/tpj.14615] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 09/26/2019] [Accepted: 10/28/2019] [Indexed: 05/12/2023]
Abstract
The salicinoids are anti-herbivore phenolic glycosides unique to the Salicaceae (Populus and Salix). They consist of a salicyl alcohol glucoside core, which is usually further acylated with benzoic, cinnamic or phenolic acids. While salicinoid structures are well known, their biosynthesis remains enigmatic. Recently, two enzymes from poplar, salicyl alcohol benzoyl transferase and benzyl alcohol benzoyl transferase, were shown to catalyze the production of salicyl benzoate, a predicted potential intermediate in salicinoid biosynthesis. Here, we used transcriptomics and co-expression analysis with these two genes to identify two UDP-glucose-dependent glycosyltransferases (UGT71L1 and UGT78M1) as candidate enzymes in this pathway. Both recombinant enzymes accepted only salicyl benzoate, salicylaldehyde and 2-hydroxycinnamic acid as glucose acceptors. Knocking out the UGT71L1 gene by CRISPR/Cas9 in poplar hairy root cultures led to the complete loss of salicortin, tremulacin and tremuloidin, and a partial reduction of salicin content. This demonstrated that UGT71L1 is required for synthesis of the major salicinoids, and suggested that an additional route can lead to salicin. CRISPR/Cas9 knockouts for UGT78M1 were not successful, and its in vivo role thus remains to be determined. Although it has a similar substrate preference and predicted structure as UGT71L1, it appears not to contribute to the synthesis of salicortin, tremulacin and tremuloidin, at least in roots. The demonstration of UGT71L1 as an enzyme of salicinoid biosynthesis will open up new avenues for the elucidation of this pathway.
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Affiliation(s)
- Christin Fellenberg
- Centre for Forest Biology and Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - Oliver Corea
- Centre for Forest Biology and Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - Lok-Hang Yan
- Department of Chemistry, University of Victoria, Victoria, British Columbia, Canada
| | - Finn Archinuk
- Centre for Forest Biology and Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - Eerik-Mikael Piirtola
- Centre for Forest Biology and Department of Biology, University of Victoria, Victoria, British Columbia, Canada
- Department of Chemistry, University of Turku, Turku, Finland
| | - Harley Gordon
- Centre for Forest Biology and Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - Michael Reichelt
- Department of Biochemistry, Max-Planck Institute for Chemical Ecology, Jena, Germany
| | - Wolfgang Brandt
- Department of Bioorganic Chemistry, Leibniz Institute for Plant Biochemistry, Halle, Germany
| | - Jeremy Wulff
- Department of Chemistry, University of Victoria, Victoria, British Columbia, Canada
| | - Jürgen Ehlting
- Centre for Forest Biology and Department of Biology, University of Victoria, Victoria, British Columbia, Canada
| | - C Peter Constabel
- Centre for Forest Biology and Department of Biology, University of Victoria, Victoria, British Columbia, Canada
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15
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Müller C, Bräutigam A, Eilers E, Junker R, Schnitzler JP, Steppuhn A, Unsicker S, van Dam N, Weisser W, Wittmann M. Ecology and Evolution of Intraspecific Chemodiversity of Plants. RESEARCH IDEAS AND OUTCOMES 2020. [DOI: 10.3897/rio.6.e49810] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
An extraordinarily high intraspecific chemical diversity, i.e. chemodiversity, has been found in several plant species, of which some are of major ecological or economic relevance. Moreover, even within an individual plant there is substantial chemodiversity among tissues and across seasons. This chemodiversity likely has pronounced ecological effects on plant mutualists and antagonists, associated foodwebs and, ultimately, biodiversity. Surprisingly, studies on interactions between plants and their herbivores or pollinators often neglect plant chemistry as a level of diversity and phenotypic variation. The main aim of this Research Unit (RU) is to understand the emergence and maintenance of intraspecific chemodiversity in plants. We address the following central questions:
1) How does plant chemodiversity vary across levels, i.e., within individuals, among individuals within populations, and among populations?
2) What are the ecological consequences of intraspecific plant chemodiversity?
3) How is plant chemodiversity genetically determined and maintained?
By combining field and laboratory studies with metabolomics, transcriptomics, genetic tools, statistical data analysis and modelling, we aim to understand causes and consequences of plant chemodiversity and elucidate its impacts on the interactions of plants with their biotic environment. Furthermore, we want to identify general principles, which hold across different species, and develop meaningful measures to describe the fascinating diversity of defence chemicals in plants. These tasks require integrated scientific collaboration of experts in experimental and theoretical ecology, including chemical and molecular ecology, (bio)chemistry and evolution.
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16
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Lackner S, Lackus ND, Paetz C, Köllner TG, Unsicker SB. Aboveground phytochemical responses to belowground herbivory in poplar trees and the consequence for leaf herbivore preference. PLANT, CELL & ENVIRONMENT 2019; 42:3293-3307. [PMID: 31350910 DOI: 10.1111/pce.13628] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 07/16/2019] [Accepted: 07/17/2019] [Indexed: 06/10/2023]
Abstract
Belowground (BG) herbivory can influence aboveground (AG) herbivore performance and food preference via changes in plant chemistry. Most evidence for this phenomenon derives from studies in herbaceous plants but studies in woody plants are scarce. Here we investigated whether and how BG herbivory on black poplar (Populus nigra) trees by Melolontha melolontha larvae influences the feeding preference of Lymantria dispar (gypsy moth) caterpillars. In a food choice assay, caterpillars preferred to feed on leaves from trees that had experienced attack by BG herbivores. Therefore, we investigated the effect of BG herbivory on the phytochemical composition of P. nigra trees alone and in combination with AG feeding by L. dispar caterpillars. BG herbivory did not increase systemic AG tree defences like volatile organic compounds, protease inhibitors and salicinoids. Jasmonates and salicylic acid were also not induced by BG herbivory in leaves but abscisic acid concentrations drastically increased together with proline and few other amino acids. Leaf coating experiments with amino acids suggest that proline might be responsible for the caterpillar feeding preference via presumptive phagostimulatory properties. This study shows that BG herbivory in poplar can modify the feeding preference of AG herbivores via phytochemical changes as a consequence of root-to-shoot signaling.
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Affiliation(s)
- Sandra Lackner
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, 07745, Jena, Germany
| | - Nathalie D Lackus
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, 07745, Jena, Germany
| | - Christian Paetz
- Research Group Biosynthesis/NMR, Max Planck Institute for Chemical Ecology, 07745, Jena, Germany
| | - Tobias G Köllner
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, 07745, Jena, Germany
| | - Sybille B Unsicker
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, 07745, Jena, Germany
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17
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McCormick AC, Irmisch S, Boeckler GA, Gershenzon J, Köllner TG, Unsicker SB. Herbivore-induced volatile emission from old-growth black poplar trees under field conditions. Sci Rep 2019; 9:7714. [PMID: 31118456 PMCID: PMC6531464 DOI: 10.1038/s41598-019-43931-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 04/25/2019] [Indexed: 11/17/2022] Open
Abstract
Herbivory is well known to trigger increased emission of volatile organic compounds (VOCs) from plants, but we know little about the responses of mature trees. We measured the volatiles emitted by leaves of old-growth black poplar (Populus nigra) trees after experimental damage by gypsy moth (Lymantria dispar) caterpillars in a floodplain forest, and studied the effect of herbivory on the transcript abundance of two genes involved in the biosynthesis of VOCs, and the accumulation of defence phytohormones. Herbivory significantly increased volatile emission from the experimentally damaged foliage, but not from adjacent undamaged leaves in the damaged branches (i.e., no systemic response). Methylbutyraldoximes, 4,8-dimethyl-1,3,7-nonatriene (DMNT), (Z)-3-hexenol and (E)-β-ocimene, amongst other compounds, were found to be important in distinguishing the blend of herbivore-damaged vs. undamaged leaves. Herbivory also increased expression of PnTPS3 (described here for the first time) and PnCYP79D6-v4 genes at the damaged sites, these genes encode for an (E)-β-ocimene synthase and a P450 enzyme involved in aldoxime formation, respectively, demonstrating de novo biosynthesis of the volatiles produced. Herbivore-damaged leaves had significantly higher levels of jasmonic acid and its conjugate (-)-jasmonic acid-isoleucine. This study shows that mature trees in the field have a robust response to herbivory, producing induced volatiles at the damaged sites even after previous natural herbivory and under changing environmental conditions, however, further studies are needed to establish whether the observed absence of systemic responses is typical of mature poplar trees or if specific conditions are required for their induction.
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Affiliation(s)
- Andrea Clavijo McCormick
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Straße 8, 07745, Jena, Germany
- Massey University, College of Sciences, Tennent Drive, 4410, Palmerston North, New Zealand
| | - Sandra Irmisch
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Straße 8, 07745, Jena, Germany
- Michael Smith Laboratories, University of British Columbia, 2185 East Mall, Vancouver, V6T 1Z4, BC, Canada
| | - G Andreas Boeckler
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Straße 8, 07745, Jena, Germany
| | - Jonathan Gershenzon
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Straße 8, 07745, Jena, Germany
| | - Tobias G Köllner
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Straße 8, 07745, Jena, Germany
| | - Sybille B Unsicker
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Straße 8, 07745, Jena, Germany.
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18
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Eberl F, Uhe C, Unsicker SB. Friend or foe? The role of leaf-inhabiting fungal pathogens and endophytes in tree-insect interactions. FUNGAL ECOL 2019. [DOI: 10.1016/j.funeco.2018.04.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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19
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Fabisch T, Gershenzon J, Unsicker SB. Specificity of Herbivore Defense Responses in a Woody Plant, Black Poplar (Populus nigra). J Chem Ecol 2019; 45:162-177. [PMID: 30788656 PMCID: PMC6469625 DOI: 10.1007/s10886-019-01050-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 01/08/2019] [Accepted: 01/21/2019] [Indexed: 11/25/2022]
Abstract
The specificity of woody plant defense responses to different attacking herbivores is poorly known. We investigated the responses of black poplar (Populus nigra) to leaf feeding by three lepidopteran species (Lymantria dispar, Laothoe populi and Amata mogadorensis) and two leaf beetle species (Phratora vulgatissima and Chrysomela populi). Of the direct defenses monitored, increases in trypsin protease inhibitor activity and the salicinoid salicin were triggered by herbivore damage, but this was not herbivore-specific. Moreover, the majority of leaf salicinoid content was present constitutively and not induced by herbivory. On the other hand, volatile emission profiles did vary among herbivore species, especially between coleopterans and lepidopterans. Monoterpenes and sesquiterpenes were induced in damaged and adjacent undamaged leaves, while the emission of green leaf volatiles, aromatic and nitrogen-containing compounds (known to attract herbivore enemies) was restricted to damaged leaves. In conclusion, indirect defenses appear to show more specific responses to attacking herbivores than direct defenses in this woody plant.
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Affiliation(s)
- Thomas Fabisch
- Max-Planck-Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745, Jena, Germany
| | - Jonathan Gershenzon
- Max-Planck-Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745, Jena, Germany
| | - Sybille B Unsicker
- Max-Planck-Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745, Jena, Germany.
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20
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Ullah C, Tsai C, Unsicker SB, Xue L, Reichelt M, Gershenzon J, Hammerbacher A. Salicylic acid activates poplar defense against the biotrophic rust fungus Melampsora larici-populina via increased biosynthesis of catechin and proanthocyanidins. THE NEW PHYTOLOGIST 2019; 221:960-975. [PMID: 30168132 PMCID: PMC6585937 DOI: 10.1111/nph.15396] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 07/10/2018] [Indexed: 05/14/2023]
Abstract
Poplar trees synthesize flavan-3-ols (catechin and proanthocyanidins) as a defense against foliar rust fungi, but the regulation of this defense response is poorly understood. Here, we investigated the role of hormones in regulating flavan-3-ol accumulation in poplar during rust infection. We profiled levels of defense hormones, signaling genes, and flavan-3-ol metabolites in black poplar leaves at different stages of rust infection. Hormone levels were manipulated by external sprays, genetic engineering, and drought to reveal their role in rust fungal defenses. Levels of salicylic acid (SA), jasmonic acid, and abscisic acid increased in rust-infected leaves and activated downstream signaling, with SA levels correlating closely with those of flavan-3-ols. Pretreatment with the SA analog benzothiadiazole increased flavan-3-ol accumulation by activating the MYB-bHLH-WD40 complex and reduced rust proliferation. Furthermore, transgenic poplar lines overproducing SA exhibited higher amounts of flavan-3-ols constitutively via the same transcriptional activation mechanism. These findings suggest a strong association among SA, flavan-3-ol biosynthesis, and rust resistance in poplars. Abscisic acid also promoted poplar defense against rust infection, but likely through stomatal immunity independent of flavan-3-ols. Jasmonic acid did not confer any apparent defense responses to the fungal pathogen. We conclude that SA activates flavan-3-ol biosynthesis in poplar against rust infection.
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Affiliation(s)
- Chhana Ullah
- Department of BiochemistryMax Planck Institute for Chemical EcologyHans‐Knöll‐Straße 807745JenaGermany
| | - Chung‐Jui Tsai
- School of Forestry and Natural ResourcesDepartment of GeneticsDepartment of Plant BiologyUniversity of GeorgiaAthensGA30602USA
| | - Sybille B. Unsicker
- Department of BiochemistryMax Planck Institute for Chemical EcologyHans‐Knöll‐Straße 807745JenaGermany
| | - Liangjiao Xue
- Key Laboratory of Forest Genetics and BiotechnologyCo‐Innovation Center for Sustainable Forestry in Southern ChinaCollege of ForestryNanjing Forestry UniversityNanjingJiangsu210037China
| | - Michael Reichelt
- Department of BiochemistryMax Planck Institute for Chemical EcologyHans‐Knöll‐Straße 807745JenaGermany
| | - Jonathan Gershenzon
- Department of BiochemistryMax Planck Institute for Chemical EcologyHans‐Knöll‐Straße 807745JenaGermany
| | - Almuth Hammerbacher
- Department of Zoology and Entomology, Forestry and Agricultural Biotechnology InstituteUniversity of PretoriaPrivate Bag X20Pretoria0028South Africa
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21
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Lackus ND, Lackner S, Gershenzon J, Unsicker SB, Köllner TG. The occurrence and formation of monoterpenes in herbivore-damaged poplar roots. Sci Rep 2018; 8:17936. [PMID: 30560919 PMCID: PMC6299004 DOI: 10.1038/s41598-018-36302-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 11/14/2018] [Indexed: 11/18/2022] Open
Abstract
Volatiles are often released upon herbivory as plant defense compounds. While the formation of volatiles above-ground has been intensively studied, little is known about herbivore-induced root volatiles. Here, we show that cockchafer larvae-damaged roots of Populus trichocarpa and P. nigra release a mixture of monoterpenes, including (−)-α-pinene, (−)-camphene, (−)-β-pinene, p-cymene, and 1,8-cineole. Three terpene synthases, PtTPS16 and PtTPS21 from P. trichocarpa and PnTPS4 from P. nigra, could be identified and characterized in vitro. PnTPS4 was found to produce 1,8-cineole as sole product. PtTPS16 and PtTPS21, although highly similar to each other, showed different product specificities and produced γ-terpinene and a mixture of (−)-camphene, (−)-α-pinene, (−)-β-pinene, and (−)-limonene, respectively. Four active site residues were found to determine the different product specificities of the two enzymes. The expression profiles of PtTPS16, PtTPS21, and PnTPS4 in undamaged and herbivore-damaged poplar roots generally matched the emission pattern of monoterpenes, indicating that monoterpene emission in roots is mainly determined at the gene transcript level. Bioassays with Phytophtora cactorum (Oomycetes) revealed inhibitory effects of vapor-phase 1,8-cineole and (−)-β-pinene on the growth of this important plant pathogen. Thus herbivore-induced volatile monoterpenes may have a role in defense against pathogens that cause secondary infections after root wounding.
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Affiliation(s)
- Nathalie D Lackus
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Strasse 8, 07745, Jena, Germany
| | - Sandra Lackner
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Strasse 8, 07745, Jena, Germany
| | - Jonathan Gershenzon
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Strasse 8, 07745, Jena, Germany
| | - Sybille B Unsicker
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Strasse 8, 07745, Jena, Germany
| | - Tobias G Köllner
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Strasse 8, 07745, Jena, Germany.
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22
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Lämke JS, Unsicker SB. Phytochemical variation in treetops: causes and consequences for tree-insect herbivore interactions. Oecologia 2018; 187:377-388. [PMID: 29473116 PMCID: PMC5997108 DOI: 10.1007/s00442-018-4087-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 02/06/2018] [Indexed: 11/27/2022]
Abstract
The interaction of plants and their herbivorous opponents has shaped the evolution of an intricate network of defences and counter-defences for millions of years. The result is an astounding diversity of phytochemicals and plant strategies to fight and survive. Trees are specifically challenged to resist the plethora of abiotic and biotic stresses due to their dimension and longevity. Here, we review the recent literature on the consequences of phytochemical variation in trees on insect-tree-herbivore interactions. We discuss the importance of genotypic and phenotypic variation in tree defence against insects and suggest some molecular mechanisms that might bring about phytochemical diversity in crowns of individual trees.
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Affiliation(s)
- Jörn S Lämke
- Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam, Germany
| | - Sybille B Unsicker
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll Str. 8, 07745, Jena, Germany.
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Crecelius AC, Michalzik B, Potthast K, Meyer S, Schubert US. Tracing the fate and transport of secondary plant metabolites in a laboratory mesocosm experiment by employing mass spectrometric imaging. Anal Bioanal Chem 2017; 409:3807-3820. [PMID: 28357483 PMCID: PMC5427159 DOI: 10.1007/s00216-017-0325-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 02/28/2017] [Accepted: 03/16/2017] [Indexed: 01/06/2023]
Abstract
Mass spectrometric imaging (MSI) has received considerable attention in recent years, since it allows the molecular mapping of various compound classes, such as proteins, peptides, glycans, secondary metabolites, lipids, and drugs in animal, human, or plant tissue sections. In the present study, the application of laser-based MSI analysis of secondary plant metabolites to monitor their transport from the grass leaves of Dactylis glomerata, over the crop of the grasshopper Chorthippus dorsatus to its excrements, and finally in the soil solution is described. This plant-herbivore-soil pathway was investigated under controlled conditions by using laboratory mesocosms. From six targeted secondary plant metabolites (dehydroquinic acid, quinic acid, apigenin, luteolin, tricin, and rosmarinic acid), only quinic acid, and dehydroquinic acid, an in-source-decay (ISD) product of quinic acid, could be traced in nearly all compartments. The tentative identification of secondary plant metabolites was performed by MS/MS analysis of methanol extracts prepared from the investigated compartments, in both the positive and negative ion mode, and subsequently compared with the results generated from the reference standards. Except for tricin, all secondary metabolites could be tentatively identified by this approach. Additional liquid-chromatography mass spectrometry (LC-MS) experiments were carried out to verify the MSI results and revealed the presence of quinic acid only in grass and chewed grass, whereas apigenin-hexoside-pentoside and luteolin-hexoisde-pentoside could be traced in the grasshopper body and excrement extracts. In summary, the MSI technique shows a trade-off between sensitivity and spatial resolution. Graphical abstract Monitoring quinic acid in a mesocosm experiment by mass spectrometric imaging (MSI).
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Affiliation(s)
- Anna C Crecelius
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany.
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743, Jena, Germany.
| | - Beate Michalzik
- Institute of Geography, Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany
| | - Karin Potthast
- Institute of Geography, Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany
| | - Stefanie Meyer
- Institute of Geography, Friedrich Schiller University Jena, Löbdergraben 32, 07743, Jena, Germany
| | - Ulrich S Schubert
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743, Jena, Germany
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Boeckler GA, Paetz C, Feibicke P, Gershenzon J, Unsicker SB. Metabolism of poplar salicinoids by the generalist herbivore Lymantria dispar (Lepidoptera). INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2016; 78:39-49. [PMID: 27503687 DOI: 10.1016/j.ibmb.2016.08.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 08/03/2016] [Accepted: 08/03/2016] [Indexed: 05/17/2023]
Abstract
The survival of insect herbivores on chemically defended plants may often depend on their ability to metabolize these defense compounds. However, only little knowledge is available on how insects actually process most plant defense compounds. We investigated the metabolism of salicinoids, a major group of phenolic glycosides in poplar and willow species, by a generalist herbivore, the gypsy moth (Lymantria dispar). Seven salicinoid metabolites identified in gypsy moth caterpillar feces were mostly conjugates with glucose, cysteine or glycine. Two of the glucosides were phosphorylated, a feature not previously reported for insect metabolites of plant defense compounds. The origins of these metabolites were traced to specific moieties of three major poplar salicinoids ingested, salicin, salicortin and tremulacin. Based on the observed metabolite patterns we were able to deduce the initial steps of salicinoid breakdown in L. dispar guts, which involves cleavage of ester bonds. The conjugated molecules were effectively eliminated within 24 h after ingestion. Some of the initial breakdown products (salicin and catechol) demonstrated negative effects on insect growth and survival in bioassays on artificial diets. Gypsy moth caterpillars with prior feeding experience on salicinoid-containing poplar foliage converted salicinoids to the identified metabolites more efficiently than caterpillars pre-fed an artificial diet. The majority of the metabolites we identified were also produced by other common poplar-feeding insects. The conversion of plant defenses like salicinoids to a variety of water-soluble sugar, phosphate and amino acid conjugates and their subsequent excretion fits the general detoxification strategy found in insect herbivores and other animals.
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Affiliation(s)
- G Andreas Boeckler
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll Str. 8, 07745, Jena, Germany.
| | - Christian Paetz
- Biosynthesis/NMR Research Group, Max Planck Institute for Chemical Ecology, Hans-Knöll Str. 8, 07745, Jena, Germany
| | - Peter Feibicke
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll Str. 8, 07745, Jena, Germany
| | - Jonathan Gershenzon
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll Str. 8, 07745, Jena, Germany
| | - Sybille B Unsicker
- Department of Biochemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll Str. 8, 07745, Jena, Germany.
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Ohse B, Hammerbacher A, Seele C, Meldau S, Reichelt M, Ortmann S, Wirth C. Salivary cues: simulated roe deer browsing induces systemic changes in phytohormones and defence chemistry in wild‐grown maple and beech saplings. Funct Ecol 2016. [DOI: 10.1111/1365-2435.12717] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Bettina Ohse
- Department of Systematic Botany and Functional Biodiversity Institute of Biology University of Leipzig Johannisallee 21, 04103 Leipzig Germany
| | - Almuth Hammerbacher
- Department of Biochemistry Max Planck Institute for Chemical Ecology Hans‐Knoell‐Strasse 8, 07745 Jena Germany
| | - Carolin Seele
- Department of Systematic Botany and Functional Biodiversity Institute of Biology University of Leipzig Johannisallee 21, 04103 Leipzig Germany
| | - Stefan Meldau
- Department of Molecular Ecology Max Planck Institute for Chemical Ecology Hans‐Knoell‐Strasse 8, 07745 Jena Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Deutscher Platz 5e, 04103 Leipzig Germany
| | - Michael Reichelt
- Department of Biochemistry Max Planck Institute for Chemical Ecology Hans‐Knoell‐Strasse 8, 07745 Jena Germany
| | - Sylvia Ortmann
- Department of Evolutionary Ecology Leibniz Institute for Zoo and Wildlife Research (IZW) Alfred‐Kowalke‐Straβe 17, 10315 Berlin Germany
| | - Christian Wirth
- Department of Systematic Botany and Functional Biodiversity Institute of Biology University of Leipzig Johannisallee 21, 04103 Leipzig Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Deutscher Platz 5e, 04103 Leipzig Germany
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26
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Rubert-Nason KF, Couture JJ, Major IT, Constabel CP, Lindroth RL. Influence of Genotype, Environment, and Gypsy Moth Herbivory on Local and Systemic Chemical Defenses in Trembling Aspen (Populus tremuloides). J Chem Ecol 2015; 41:651-61. [PMID: 26099738 DOI: 10.1007/s10886-015-0600-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 06/01/2015] [Accepted: 06/12/2015] [Indexed: 01/10/2023]
Abstract
Numerous studies have explored the impacts of intraspecific genetic variation and environment on the induction of plant chemical defenses by herbivory. Relatively few, however, have considered how those factors affect within-plant distribution of induced defenses. This work examined the impacts of plant genotype and soil nutrients on the local and systemic phytochemical responses of trembling aspen (Populus tremuloides) to defoliation by gypsy moth (Lymantria dispar). We deployed larvae onto foliage on individual tree branches for 15 days and then measured chemistry in leaves from: 1) branches receiving damage, 2) undamaged branches of insect-damaged trees, and 3) branches of undamaged control trees. The relationship between post-herbivory phytochemical variation and insect performance also was examined. Plant genotype, soil nutrients, and damage all influenced phytochemistry, with genotype and soil nutrients being stronger determinants than damage. Generally, insect damage decreased foliar nitrogen, increased levels of salicinoids and condensed tannins, but had little effect on levels of a Kunitz trypsin inhibitor, TI3. The largest damage-mediated tannin increases occurred in leaves on branches receiving damage, whereas the largest salicinoid increases occurred in leaves of adjacent, undamaged branches. Foliar nitrogen and the salicinoid tremulacin had the strongest positive and negative relationships, respectively, with insect growth. Overall, plant genetics and environment concomitantly influenced both local and systemic phytochemical responses to herbivory. These findings suggest that herbivory can contribute to phytochemical heterogeneity in aspen foliage, which may in turn influence future patterns of herbivory and nutrient cycling over larger spatial scales.
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Affiliation(s)
- Kennedy F Rubert-Nason
- Department of Entomology, University of Wisconsin, 1630 Linden Dr., Madison, WI, 53706, USA,
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Chedgy RJ, Köllner TG, Constabel CP. Functional characterization of two acyltransferases from Populus trichocarpa capable of synthesizing benzyl benzoate and salicyl benzoate, potential intermediates in salicinoid phenolic glycoside biosynthesis. PHYTOCHEMISTRY 2015; 113:149-59. [PMID: 25561400 DOI: 10.1016/j.phytochem.2014.10.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 10/07/2014] [Accepted: 10/16/2014] [Indexed: 05/19/2023]
Abstract
Salicinoids are phenolic glycosides (PGs) characteristic of the Salicaceae and are known defenses against insect herbivory. Common examples are salicin, salicortin, tremuloidin, and tremulacin, which accumulate to high concentrations in the leaves and bark of willows and poplars. Although their biosynthetic pathway is not known, recent work has suggested that benzyl benzoate may be a potential biosynthetic intermediate. Two candidate genes, named PtACT47 and PtACT49, encoding BAHD-type acyl transferases were identified and are predicted to produce such benzylated secondary metabolites. Herein described are the cDNA cloning, heterologous expression and in vitro functional characterization of these two BAHD acyltransferases. Recombinant PtACT47 exhibited low substrate selectivity and could utilize acetyl-CoA, benzoyl-CoA, and cinnamoyl-CoA as acyl donors with a variety of alcohols as acyl acceptors. This enzyme showed the greatest Km/Kcat ratio (45.8 nM(-1) s(-1)) and lowest Km values (45.1 μM) with benzoyl-CoA and salicyl alcohol, and was named benzoyl-CoA: salicyl alcohol O-benzoyltransferase (PtSABT). Recombinant PtACT49 utilized a narrower range of substrates, including benzoyl-CoA and acetyl-CoA and a limited number of alcohols. Its highest Km/Kcat (31.8 nM(-1) s(-1)) and lowest Km (55.3 μM) were observed for benzoyl-CoA and benzyl alcohol, and it was named benzoyl-CoA: benzyl alcohol O-benzoyltransferase (PtBEBT). Both enzymes were also capable of synthesizing plant volatile alcohol esters, such as hexenyl benzoate, at trace levels. Although the activities demonstrated are consistent with roles in salicinoid biosynthesis, direct tests of this hypothesis using transgenic poplar must still be performed.
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Affiliation(s)
- Russell J Chedgy
- Centre for Forest Biology, Department of Biology, University of Victoria, P.O. Box 3020, STN CSC, Victoria, BC V8W 3N5, Canada
| | - Tobias G Köllner
- Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany
| | - C Peter Constabel
- Centre for Forest Biology, Department of Biology, University of Victoria, P.O. Box 3020, STN CSC, Victoria, BC V8W 3N5, Canada.
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Massad TJ, Trumbore SE, Ganbat G, Reichelt M, Unsicker S, Boeckler A, Gleixner G, Gershenzon J, Ruehlow S. An optimal defense strategy for phenolic glycoside production in Populus trichocarpa--isotope labeling demonstrates secondary metabolite production in growing leaves. THE NEW PHYTOLOGIST 2014; 203:607-619. [PMID: 24739022 DOI: 10.1111/nph.12811] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 03/11/2014] [Indexed: 05/14/2023]
Abstract
Large amounts of carbon are required for plant growth, but young, growing tissues often also have high concentrations of defensive secondary metabolites. Plants' capacity to allocate resources to growth and defense is addressed by the growth-differentiation balance hypothesis and the optimal defense hypothesis, which make contrasting predictions. Isotope labeling can demonstrate whether defense compounds are synthesized from stored or newly fixed carbon, allowing a detailed examination of these hypotheses. Populus trichocarpa saplings were pulse-labeled with 13CO2 at the beginning and end of a growing season, and the 13C signatures of phenolic glycosides (salicinoids), sugars, bulk tissue, and respired CO2 were traced over time. Half of the saplings were also subjected to mechanical damage. Populus trichocarpa followed an optimal defense strategy, investing 13C in salicinoids in expanding leaves directly after labeling. Salicinoids turned over quickly, and their production continued throughout the season. Salicin was induced by early-season damage, further demonstrating optimal defense. Salicinoids appear to be of great value to P. trichocarpa, as they command new C both early and late in the growing season, but their fitness benefits require further study. Export of salicinoids between tissues and biochemical pathways enabling induction also needs research. Nonetheless, the investigation of defense production afforded by isotope labeling lends new insights into plants' ability to grow and defend simultaneously.
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Affiliation(s)
- Tara Joy Massad
- Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, 07745, Jena, Germany
- Instituto de Química, Universidade de São Paulo, Av. Prof. Lineu Prestes 748, Bloco 11T (Sala 1124), São Paulo, SP, 05508-000, Brazil
| | - Susan E Trumbore
- Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, 07745, Jena, Germany
| | - Gantsetseg Ganbat
- Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, 07745, Jena, Germany
| | - Michael Reichelt
- Max Planck Insitute for Chemical Ecology, Hans-Knöll-Str. 8, 07745, Jena, Germany
| | - Sybille Unsicker
- Max Planck Insitute for Chemical Ecology, Hans-Knöll-Str. 8, 07745, Jena, Germany
| | - Andreas Boeckler
- Max Planck Insitute for Chemical Ecology, Hans-Knöll-Str. 8, 07745, Jena, Germany
| | - Gerd Gleixner
- Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, 07745, Jena, Germany
| | - Jonathan Gershenzon
- Max Planck Insitute for Chemical Ecology, Hans-Knöll-Str. 8, 07745, Jena, Germany
| | - Steffen Ruehlow
- Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, 07745, Jena, Germany
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29
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Boeckler GA, Towns M, Unsicker SB, Mellway RD, Yip L, Hilke I, Gershenzon J, Constabel CP. Transgenic upregulation of the condensed tannin pathway in poplar leads to a dramatic shift in leaf palatability for two tree-feeding Lepidoptera. J Chem Ecol 2014; 40:150-8. [PMID: 24496605 DOI: 10.1007/s10886-014-0383-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 01/10/2014] [Accepted: 01/16/2014] [Indexed: 11/29/2022]
Abstract
Transgenic hybrid aspen (Populus tremula x tremuloides) overexpressing the MYB134 tannin regulatory gene show dramatically enhanced condensed tannin (proanthocyanidin) levels, as well as shifts in other phenolic metabolites. A series of insect bioassays with forest tent caterpillars (Malacosoma disstria) and gypsy moth (Lymantria dispar) caterpillars was carried out to determine how this metabolic shift affects food preference and performance of generalist tree-feeding lepidopterans. Both species showed a distinct preference for the high-tannin MYB134 overexpressor plants, and L. dispar performance was enhanced relative to controls. L. dispar reached greater pupal weight and showed reduced time to pupation when reared on the MYB134 overexpressing poplar. These results were unexpected since enhanced condensed tannin levels were predicted to act as feeding deterrents. However, the data may be explained by the observed decrease in the salicinoids (phenolic glycosides) salicortin and tremulacin that accompanied the upregulation of the condensed tannins in the transgenics. We conclude that for these two lepidopteran species, condensed tannin levels are unlikely to be a major determinant of caterpillar food preference or performance. However, our experiments show that overexpression of a single regulatory gene in transgenic aspen can have a significant impact on herbivorous insects.
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Affiliation(s)
- G Andreas Boeckler
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll Strasse 8, 07745, Jena, Germany
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