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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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2
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Shay PE, Winder RS, Constabel CP, Trofymow JA(T. Fungal Community Composition as Affected by Litter Chemistry and Weather during Four Years of Litter Decomposition in Rainshadow Coastal Douglas-Fir Forests. J Fungi (Basel) 2022; 8:jof8070735. [PMID: 35887490 PMCID: PMC9323820 DOI: 10.3390/jof8070735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Revised: 07/07/2022] [Accepted: 07/13/2022] [Indexed: 12/04/2022] Open
Abstract
Climate and litter chemistry are major factors influencing litter decay, a process mediated by microbes, such as fungi, nitrogen-fixing bacteria and ammonia-oxidizing bacteria. Increasing atmospheric CO2 concentrations can decrease nitrogen (N) and increase condensed tannin (CT) content in foliar litter, reducing litter quality and slowing decomposition. We hypothesized that reduced litter quality inhibits microbes and is the mechanism causing decomposition to slow. Litterbags of Douglas-fir needles and poplar leaves with a range of N (0.61–1.57%) and CT (2.1–29.1%) treatment and natural acid unhydrolyzable residue (35.3–41.5%) concentrations were placed along climatic gradients in mature Douglas-fir stands of coastal British Columbia rainshadow forests. The structure (diversity, richness and evenness) and composition of microbial communities were analyzed using DGGE profiles of 18S, NifH-universal and AmoA PCR amplicons in foliar litter after 7, 12, 24 and 43 months of decay. High CT and low N concentrations in leaf litter were associated with changes in microbial community composition, especially fungi. Contrary to our hypothesis, high CT and low N treatments did not inhibit microbial colonization or diversity. The joint effects of air temperature and soil moisture on microbial community composition at our sites were more important than the effects of initial litter chemistry.
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Affiliation(s)
- Philip-Edouard Shay
- Centre for Forest Biology, Department of Biology, University of Victoria, Victoria, BC V8W 3N5, Canada; (P.-E.S.); (C.P.C.)
- Pacific Forestry Centre, Canadian Forest Service, 506 West Burnside Road, Victoria, BC V8Z 1M5, Canada;
| | - Richard S. Winder
- Pacific Forestry Centre, Canadian Forest Service, 506 West Burnside Road, Victoria, BC V8Z 1M5, Canada;
| | - C. Peter Constabel
- Centre for Forest Biology, Department of Biology, University of Victoria, Victoria, BC V8W 3N5, Canada; (P.-E.S.); (C.P.C.)
| | - J. A. (Tony) Trofymow
- Centre for Forest Biology, Department of Biology, University of Victoria, Victoria, BC V8W 3N5, Canada; (P.-E.S.); (C.P.C.)
- Pacific Forestry Centre, Canadian Forest Service, 506 West Burnside Road, Victoria, BC V8Z 1M5, Canada;
- Correspondence:
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3
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Extracts of Waste from Poplar Wood Processing Alleviate Experimental Dextran Sulfate-Induced Colitis by Ameliorating Oxidative Stress, Inhibiting the Th1/Th17 Response and Inducing Apoptosis in Inflammatory Lymphocytes. Antioxidants (Basel) 2021; 10:antiox10111684. [PMID: 34829556 PMCID: PMC8614834 DOI: 10.3390/antiox10111684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 10/19/2021] [Accepted: 10/20/2021] [Indexed: 11/16/2022] Open
Abstract
As a fast-growing tree, poplar is widely planted and typically used for wood processing in China. During poplar wood processing, a large amount of poplar sawdust (PS) and poplar leaves (PL) are produced and abandoned. To make full use of poplar resources and clarify the use of poplar as a feed additive, the active ingredients in PS and PL were extracted and isolated, and the anti-inflammatory effects of the extracts on mice with dextran sulfate sodium (DSS)-induced colitis were investigated. In vitro anti-inflammatory experiments showed that the ethyl acetate extract of PS and PL (PSE and PLE, respectively) could significantly inhibit the proliferation of concanavalin A (Con A)-activated lymphocytes. Salicortin, tremulacin and salireposide were identified in both PSE and PLE. Oral administration of PSE and PLE rescued DSS-induced colonic shortening, repaired tissue damage, and decreased the disease activity index (DAI). The antioxidant capacity, including the increased activities of glutathione peroxidase (GSH-Px), total superoxide dismutase (T-SOD and catalase (CAT) and decreased activity of myeloperoxidase (MPO), in the colons of mice with colitis was enhanced through the activation of ERK after treatment with PSE and PLE. The ratio of Th1 to Th17 cells, which can lead to inflammation in the spleen, was significantly decreased by the administration of PSE and PLE, while the phosphorylation of related transcription factors (p65, STAT1, and STAT3) was inhibited. Furthermore, PSE and PLE could induce apoptosis in Con A-activated lymphocytes, which may be associated with the increase in p-TBK1, as the molecular docking results also indicated that salireposide in PSE and PLE could interact with the TBK1 protein. Overall, our study provides a promising feed additive for improving intestinal inflammation in animals and a method for the full utilization of poplar resources.
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4
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Domestication does not alter invasion risk of a non-native legume. Oecologia 2021; 196:317-329. [PMID: 33576901 DOI: 10.1007/s00442-021-04866-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 01/22/2021] [Indexed: 10/22/2022]
Abstract
Most non-native domesticated plants provide benefits without escaping cultivation, but others have become prominent invaders. A better understanding of how domestication might alter plant traits that influence the ability of species to overcome barriers to invasion could improve invasion risk predictions. We explored how variation in foliar chemistry among cultivars of a widespread invader in the U.S. (Lespedeza cuneata) might influence invasion risk through differences in herbivore interactions and a potential tradeoff with competitive ability. In a no-choice feeding bioassay a generalist herbivore performed better when fed cultivars compared to wild genotypes and native congeners, suggesting domesticated L. cuneata may be more vulnerable to herbivory compared to wild genotypes. However, in a factorial greenhouse experiment, with treatments of herbivory and competition, all cultivars had similar seed and biomass production as the wild genotype. Competition with native species reduced productivity of all L. cuneata types, while experimental herbivory alone did not. We also found far less variation in foliar chemistry among L. cuneata types than expected based on domestication history. While our findings from the bioassay suggest potentially lower invasion risk for cultivars if herbivore populations expand more rapidly when feeding on cultivars, we did not find evidence that cultivars had different responses to herbivory or competition with native species in the greenhouse experiment. Altogether, the findings from our multi-pronged approach for evaluating potential factors underlying invasion success of a domesticated species indicate that domestication has not altered invasion risk of this widespread plant invader.
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5
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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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6
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Barton KE, Edwards KF, Koricheva J. Shifts in woody plant defence syndromes during leaf development. Funct Ecol 2019. [DOI: 10.1111/1365-2435.13435] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kasey E. Barton
- Department of Botany University of Hawai'i at Mānoa Honolulu Hawai'I USA
| | - Kyle F. Edwards
- Department of Oceanography University of Hawai'i at Mānoa Honolulu Hawai'I USA
| | - Julia Koricheva
- School of Biological Sciences Royal Holloway University of London Egham UK
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7
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Selmants PC, Schweitzer JA, Adair KL, Holeski LM, Lindroth RL, Hart SC, Whitham TG. Genetic variation in tree leaf chemistry predicts the abundance and activity of autotrophic soil microorganisms. Ecosphere 2019. [DOI: 10.1002/ecs2.2795] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Paul C. Selmants
- U.S. Geological Survey Western Geographic Science Center Menlo Park California USA
| | - Jennifer A. Schweitzer
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee USA
| | - Karen L. Adair
- Institute of Ecology and Evolution University of Oregon Eugene Oregon USA
| | - Liza M. Holeski
- Department of Biological Sciences Northern Arizona University Flagstaff Arizona USA
| | - Richard L. Lindroth
- Department of Entomology University of Wisconsin‐Madison Madison Wisconsin USA
| | - Stephen C. Hart
- Department of Life & Environmental Sciences Sierra Nevada Research Institute University of California Merced California USA
| | - Thomas G. Whitham
- Department of Biological Sciences Northern Arizona University Flagstaff Arizona USA
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8
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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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9
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Woolbright SA, Rehill BJ, Lindroth RL, DiFazio SP, Martinsen GD, Zinkgraf MS, Allan GJ, Keim P, Whitham TG. Large effect quantitative trait loci for salicinoid phenolic glycosides in Populus: Implications for gene discovery. Ecol Evol 2018; 8:3726-3737. [PMID: 29686853 PMCID: PMC5901179 DOI: 10.1002/ece3.3932] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 01/11/2018] [Accepted: 01/23/2018] [Indexed: 01/01/2023] Open
Abstract
Genomic studies have been used to identify genes underlying many important plant secondary metabolic pathways. However, genes for salicinoid phenolic glycosides (SPGs)—ecologically important compounds with significant commercial, cultural, and medicinal applications—remain largely undescribed. We used a linkage map derived from a full‐sib population of hybrid cottonwoods (Populus spp.) to search for quantitative trait loci (QTL) for the SPGs salicortin and HCH‐salicortin. SSR markers and primer sequences were used to anchor the map to the V3.0 P. trichocarpa genome. We discovered 21 QTL for the two traits, including a major QTL for HCH‐salicortin (R2 = .52) that colocated with a QTL for salicortin on chr12. Using the V3.0 Populus genome sequence, we identified 2,983 annotated genes and 1,480 genes of unknown function within our QTL intervals. We note ten candidate genes of interest, including a BAHD‐type acyltransferase that has been potentially linked to PopulusSPGs. Our results complement other recent studies in Populus with implications for gene discovery and the evolution of defensive chemistry in a model genus. To our knowledge, this is the first study to use a full‐sib mapping population to identify QTL intervals and gene lists associated with SPGs.
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Affiliation(s)
- Scott A Woolbright
- Department of Biology University of Arkansas at Little Rock Little Rock AR USA
| | - Brian J Rehill
- Department of Chemistry US Naval Academy Annapolis MD USA
| | | | | | - Gregory D Martinsen
- Environmental Genetics and Genomics Laboratory (EnGGen) Department of Biological Sciences Merriam-Powell Center for Environmental Research Northern Arizona University Flagstaff AZ USA
| | | | - Gerard J Allan
- Environmental Genetics and Genomics Laboratory (EnGGen) Department of Biological Sciences Merriam-Powell Center for Environmental Research Northern Arizona University Flagstaff AZ USA
| | - Paul Keim
- Department of Biological Sciences Pathogen and Microbe Institute Northern Arizona University Flagstaff AZ USA
| | - Thomas G Whitham
- Environmental Genetics and Genomics Laboratory (EnGGen) Department of Biological Sciences Merriam-Powell Center for Environmental Research Northern Arizona University Flagstaff AZ USA
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10
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Phenolic Glycosides in Populus tremuloides and their Effects on Long-Term Ungulate Browsing. J Chem Ecol 2017; 43:1023-1030. [DOI: 10.1007/s10886-017-0895-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 09/26/2017] [Accepted: 10/09/2017] [Indexed: 10/18/2022]
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11
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Jarvis KJ, Allan GJ, Craig AJ, Beresic-Perrins RK, Wimp G, Gehring CA, Whitham TG. Arthropod communities on hybrid and parental cottonwoods are phylogenetically structured by tree type: Implications for conservation of biodiversity in plant hybrid zones. Ecol Evol 2017; 7:5909-5921. [PMID: 28808554 PMCID: PMC5551273 DOI: 10.1002/ece3.3146] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 05/17/2017] [Indexed: 02/03/2023] Open
Abstract
Although hybridization in plants has been recognized as an important pathway in plant speciation, it may also affect the ecology and evolution of associated communities. Cottonwood species (Populus angustifolia and P. fremontii) and their naturally occurring hybrids are known to support different plant, animal, and microbial communities, but no studies have examined community structure within the context of phylogenetic history. Using a community composed of 199 arthropod species, we tested for differences in arthropod phylogenetic patterns within and among hybrid and parental tree types in a common garden. Three major patterns emerged. (1) Phylogenetic diversity (PD) was significantly different between arthropod communities on hybrids and Fremont cottonwood when pooled by tree type. (2) Mean phylogenetic distance (MPD) and net relatedness index (NRI) indicated that communities on hybrid trees were significantly more phylogenetically overdispersed than communities on either parental tree type. (3) Community distance (Dpw) indicated that communities on hybrids were significantly different than parental species. Our results show that arthropod communities on parental and hybrid cottonwoods exhibit significantly different patterns of phylogenetic structure. This suggests that arthropod community assembly is driven, in part, by plant-arthropod interactions at the level of cottonwood tree type. We discuss potential hypotheses to explain the effect of plant genetic dissimilarity on arthropod phylogenetic community structure, including the role of competition and environmental filtering. Our findings suggest that cottonwood species and their hybrids function as evolutionarily significant units (ESUs) that affect the assembly and composition of associated arthropod communities and deserve high priority for conservation.
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Affiliation(s)
- Karl J Jarvis
- School of Forestry Northern Arizona University Flagstaff AZ USA.,Biology Department Southern Utah University Cedar City UT USA
| | - Gerard J Allan
- Department of Biological Sciences Northern Arizona University Flagstaff AZ USA.,Merriam-Powell Center for Environmental Research Flagstaff AZ USA
| | - Ashley J Craig
- Department of Biological Sciences Northern Arizona University Flagstaff AZ USA
| | | | - Gina Wimp
- Department of Biology Georgetown University Washington DC USA
| | - Catherine A Gehring
- Department of Biological Sciences Northern Arizona University Flagstaff AZ USA.,Merriam-Powell Center for Environmental Research Flagstaff AZ USA
| | - Thomas G Whitham
- Department of Biological Sciences Northern Arizona University Flagstaff AZ USA.,Merriam-Powell Center for Environmental Research Flagstaff AZ USA
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Buhl C, Meilan R, Lindroth RL. Genetic Modification of Lignin in Hybrid Poplar (Populus alba × Populus tremula) Does Not Substantially Alter Plant Defense or Arthropod Communities. JOURNAL OF INSECT SCIENCE (ONLINE) 2017; 17:3858857. [PMID: 28973575 PMCID: PMC5538326 DOI: 10.1093/jisesa/iex052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Indexed: 06/07/2023]
Abstract
Lignin impedes access to cellulose during biofuel production and pulping but trees can be genetically modified to improve processing efficiency. Modification of lignin may have nontarget effects on mechanical and chemical resistance and subsequent arthropod community responses with respect to pest susceptibility and arthropod biodiversity. We quantified foliar mechanical and chemical resistance traits in lignin-modified and wild-type (WT) poplar (Populus alba × Populus tremula) grown in a plantation and censused arthropods present on these trees to determine total abundance, as well as species richness, diversity and community composition. Our results indicate that mechanical resistance was not affected by lignin modification and only one genetic construct resulted in a (modest) change in chemical resistance. Arthropod abundance and community composition were consistent across modified and WT trees, but transgenics produced using one construct exhibited higher species richness and diversity relative to the WT. Our findings indicate that modification of lignin in poplar does not negatively affect herbivore resistance traits or arthropod community response, and may even result in a source of increased genetic diversity in trees and arthropod communities.
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Affiliation(s)
- Christine Buhl
- Department of Entomology, University of Wisconsin-Madison, 1630 Linden Dr., Madison, WI 53706 (; )
- Current address: 2600 State St., Salem, OR 97310
| | - Richard Meilan
- Department of Forestry and Natural Resources, Purdue University, 715 W. State St., West Lafayette, IN 47907 ()
| | - Richard L. Lindroth
- Department of Entomology, University of Wisconsin-Madison, 1630 Linden Dr., Madison, WI 53706 (; )
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13
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Brunner AM, Varkonyi-Gasic E, Jones RC. Phase Change and Phenology in Trees. COMPARATIVE AND EVOLUTIONARY GENOMICS OF ANGIOSPERM TREES 2017. [DOI: 10.1007/7397_2016_30] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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14
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Wang XF, Liu JF, Gao WQ, Deng YP, Ni YY, Xiao YH, Kang FF, Wang Q, Lei JP, Jiang ZP. Defense pattern of Chinese cork oak across latitudinal gradients: influences of ontogeny, herbivory, climate and soil nutrients. Sci Rep 2016; 6:27269. [PMID: 27252112 PMCID: PMC4890039 DOI: 10.1038/srep27269] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 05/09/2016] [Indexed: 11/09/2022] Open
Abstract
Knowledge of latitudinal patterns in plant defense and herbivory is crucial for understanding the mechanisms that govern ecosystem functioning and for predicting their responses to climate change. Using a widely distributed species in East Asia, Quercus variabilis, we aim to reveal defense patterns of trees with respect to ontogeny along latitudinal gradients. Six leaf chemical (total phenolics and total condensed tannin concentrations) and physical (cellulose, hemicellulose, lignin and dry mass concentration) defensive traits as well as leaf herbivory (% leaf area loss) were investigated in natural Chinese cork oak (Q. variabilis) forests across two ontogenetic stages (juvenile and mature trees) along a ~14°-latitudinal gradient. Our results showed that juveniles had higher herbivory values and a higher concentration of leaf chemical defense substances compared with mature trees across the latitudinal gradient. In addition, chemical defense and herbivory in both ontogenetic stages decreased with increasing latitude, which supports the latitudinal herbivory-defense hypothesis and optimal defense theory. The identified trade-offs between chemical and physical defense were primarily determined by environmental variation associated with the latitudinal gradient, with the climatic factors (annual precipitation, minimum temperature of the coldest month) largely contributing to the latitudinal defense pattern in both juvenile and mature oak trees.
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Affiliation(s)
- Xiao-Fei Wang
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
| | - Jian-Feng Liu
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
| | - Wen-Qiang Gao
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
| | - Yun-Peng Deng
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
| | - Yan-Yan Ni
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
| | - Yi-Hua Xiao
- The Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou 510520, China
| | - Feng-Feng Kang
- College of Forestry, Beijing Forestry University, Beijing 100083, China
| | - Qi Wang
- Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou 510650, China
| | - Jing-Pin Lei
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
| | - Ze-Ping Jiang
- State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China
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15
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Plant genotype influences aquatic‐terrestrial ecosystem linkages through timing and composition of insect emergence. Ecosphere 2016. [DOI: 10.1002/ecs2.1331] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Borzak CL, Potts BM, Davies NW, O'Reilly-Wapstra JM. Population divergence in the ontogenetic trajectories of foliar terpenes of a Eucalyptus species. ANNALS OF BOTANY 2015; 115:159-170. [PMID: 25434028 PMCID: PMC4284115 DOI: 10.1093/aob/mcu222] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 08/27/2014] [Accepted: 09/26/2014] [Indexed: 06/02/2023]
Abstract
BACKGROUND AND AIMS The development of plant secondary metabolites during early life stages can have significant ecological and evolutionary implications for plant-herbivore interactions. Foliar terpenes influence a broad range of ecological interactions, including plant defence, and their expression may be influenced by ontogenetic and genetic factors. This study investigates the role of these factors in the expression of foliar terpene compounds in Eucalyptus globulus seedlings. METHODS Seedlings were sourced from ten families each from three genetically distinct populations, representing relatively high and low chemical resistance to mammalian herbivory. Cotyledon-stage seedlings and consecutive leaf pairs of true leaves were harvested separately across an 8-month period, and analysed for eight monoterpene compounds and six sesquiterpene compounds. KEY RESULTS Foliar terpenes showed a series of dynamic changes with ontogenetic trajectories differing between populations and families, as well as between and within the two major terpene classes. Sesquiterpenes changed rapidly through ontogeny and expressed opposing trajectories between compounds, but showed consistency in pattern between populations. Conversely, changed expression in monoterpene trajectories was population- and compound-specific. CONCLUSIONS The results suggest that adaptive opportunities exist for changing levels of terpene content through ontogeny, and evolution may exploit the ontogenetic patterns of change in these compounds to create a diverse ontogenetic chemical mosaic with which to defend the plant. It is hypothesized that the observed genetically based patterns in terpene ontogenetic trajectories reflect multiple changes in the regulation of genes throughout different terpene biosynthetic pathways.
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Affiliation(s)
- Christina L Borzak
- School of Biological Sciences and National Centre for Future Forest Industries, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia and Central Science Laboratory, University of Tasmania, Private Bag 74, Hobart, Tasmania, 7001, Australia
| | - Brad M Potts
- School of Biological Sciences and National Centre for Future Forest Industries, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia and Central Science Laboratory, University of Tasmania, Private Bag 74, Hobart, Tasmania, 7001, Australia
| | - Noel W Davies
- School of Biological Sciences and National Centre for Future Forest Industries, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia and Central Science Laboratory, University of Tasmania, Private Bag 74, Hobart, Tasmania, 7001, Australia
| | - Julianne M O'Reilly-Wapstra
- School of Biological Sciences and National Centre for Future Forest Industries, University of Tasmania, Private Bag 55, Hobart, Tasmania, 7001, Australia and Central Science Laboratory, University of Tasmania, Private Bag 74, Hobart, Tasmania, 7001, Australia
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Maldonado-López Y, Cuevas-Reyes P, González-Rodríguez A, Pérez-López G, Acosta-Gómez C, Oyama K. Relationships among plant genetics, phytochemistry and herbivory patterns in Quercus castanea across a fragmented landscape. Ecol Res 2014. [DOI: 10.1007/s11284-014-1218-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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18
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Quintero C, Lampert EC, Bowers MD. Time is of the essence: direct and indirect effects of plant ontogenetic trajectories on higher trophic levels. Ecology 2014. [DOI: 10.1890/13-2249.1] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Couture JJ, Holeski LM, Lindroth RL. Long-term exposure to elevated CO2 and O3 alters aspen foliar chemistry across developmental stages. PLANT, CELL & ENVIRONMENT 2014; 37:758-765. [PMID: 24006844 DOI: 10.1111/pce.12195] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 08/23/2013] [Accepted: 08/27/2013] [Indexed: 06/02/2023]
Abstract
Anthropogenic activities are altering levels of greenhouse gases to the extent that multiple and diverse ecosystem processes are being affected. Two gases that substantially influence forest health are atmospheric carbon dioxide (CO2 ) and tropospheric ozone (O3 ). Plant chemistry will play an important role in regulating ecosystem processes in future environments, but little information exists about the longitudinal effects of elevated CO2 and O3 on phytochemistry, especially for long-lived species such as trees. To address this need, we analysed foliar chemical data from two genotypes of trembling aspen, Populus tremuloides, collected over 10 years of exposure to levels of CO2 and O3 predicted for the year 2050. Elevated CO2 and O3 altered both primary and secondary chemistry, and the magnitude and direction of the responses varied across developmental stages and between aspen genotypes. Our findings suggest that the effects of CO2 and O3 on phytochemical traits that influence forest processes will vary over tree developmental stages, highlighting the need to continue long-term, experimental atmospheric change research.
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Affiliation(s)
- J J Couture
- Department of Entomology, University of Wisconsin, 237 Russell Laboratories, 1630 Linden Dr., Madison, WI, 53706, USA
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20
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Pregitzer CC, Bailey JK, Schweitzer JA. Genetic by environment interactions affect plant-soil linkages. Ecol Evol 2013; 3:2322-33. [PMID: 23919173 PMCID: PMC3728968 DOI: 10.1002/ece3.618] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 04/21/2013] [Accepted: 05/01/2013] [Indexed: 11/16/2022] Open
Abstract
The role of plant intraspecific variation in plant–soil linkages is poorly understood, especially in the context of natural environmental variation, but has important implications in evolutionary ecology. We utilized three 18- to 21-year-old common gardens across an elevational gradient, planted with replicates of five Populus angustifolia genotypes each, to address the hypothesis that tree genotype (G), environment (E), and G × E interactions would affect soil carbon and nitrogen dynamics beneath individual trees. We found that soil nitrogen and carbon varied by over 50% and 62%, respectively, across all common garden environments. We found that plant leaf litter (but not root) traits vary by genotype and environment while soil nutrient pools demonstrated genotype, environment, and sometimes G × E interactions, while process rates (net N mineralization and net nitrification) demonstrated G × E interactions. Plasticity in tree growth and litter chemistry was significantly related to the variation in soil nutrient pools and processes across environments, reflecting tight plant–soil linkages. These data overall suggest that plant genetic variation can have differential affects on carbon storage and nitrogen cycling, with implications for understanding the role of genetic variation in plant–soil feedback as well as management plans for conservation and restoration of forest habitats with a changing climate.
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Affiliation(s)
- Clara C Pregitzer
- Department of Ecology and Evolutionary Biology, University of Tennessee Knoxville, Tennessee
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21
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Compson ZG, Adams KJ, Edwards JA, Maestas JM, Whitham TG, Marks JC. Leaf litter quality affects aquatic insect emergence: contrasting patterns from two foundation trees. Oecologia 2013; 173:507-19. [PMID: 23532583 DOI: 10.1007/s00442-013-2643-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 03/07/2013] [Indexed: 10/27/2022]
Abstract
Reciprocal subsidies between rivers and terrestrial habitats are common where terrestrial leaf litter provides energy to aquatic invertebrates while emerging aquatic insects provide energy to terrestrial predators (e.g., birds, lizards, spiders). We examined how aquatic insect emergence changed seasonally with litter from two foundation riparian trees, whose litter often dominates riparian streams of the southwestern United States: Fremont (Populus fremontii) and narrowleaf (Populus angustifolia) cottonwood. P. fremontii litter is fast-decomposing and lower in defensive phytochemicals (i.e., condensed tannins, lignin) relative to P. angustifolia. We experimentally manipulated leaf litter from these two species by placing them in leaf enclosures with emergence traps attached in order to determine how leaf type influenced insect emergence. Contrary to our initial predictions, we found that packs with slow-decomposing leaves tended to support more emergent insects relative to packs with fast-decomposing leaves. Three findings emerged. Firstly, abundance (number of emerging insects m(-2) day(-1)) was 25% higher on narrowleaf compared to Fremont leaves for the spring but did not differ in the fall, demonstrating that leaf quality from two dominant trees of the same genus yielded different emergence patterns and that these patterns changed seasonally. Secondly, functional feeding groups of emerging insects differed between treatments and seasons. Specifically, in the spring collector-gatherer abundance and biomass were higher on narrowleaf leaves, whereas collector-filterer abundance and biomass were higher on Fremont leaves. Shredder abundance and biomass were higher on narrowleaf leaves in the fall. Thirdly, diversity (Shannon's H') was higher on Fremont leaves in the spring, but no differences were found in the fall, showing that fast-decomposing leaves can support a more diverse, complex emergent insect assemblage during certain times of the year. Collectively, these results challenge the notion that leaf quality is a simple function of decomposition, suggesting instead that aquatic insects benefit differentially from different leaf types, such that some use slow-decomposing litter for habitat and its temporal longevity and others utilize fast-decomposing litter with more immediate nutrient release.
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Affiliation(s)
- Zacchaeus G Compson
- Merriam-Powell Center for Environmental Research, Department of Biological Sciences, Northern Arizona University, 617 S. Beaver St., P. O. Box 5640, Flagstaff, AZ, 86011-5640, USA,
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22
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Whitehead SR, Bowers MD. Iridoid and secoiridoid glycosides in a hybrid complex of bush honeysuckles (Lonicera spp., Caprifolicaceae): implications for evolutionary ecology and invasion biology. PHYTOCHEMISTRY 2013; 86:57-63. [PMID: 23228598 DOI: 10.1016/j.phytochem.2012.10.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 09/06/2012] [Accepted: 10/16/2012] [Indexed: 05/21/2023]
Abstract
Interspecific hybridization among non-native plant species can generate genotypes that are more reproductively successful in the introduced habitat than either parent. One important mechanism that may serve as a stimulus for the evolution of invasiveness in hybrids is increased variation in secondary metabolite chemistry, but still very little is known about patterns of chemical trait introgression in plant hybrid zones. This study examined the occurrence of iridoid and secoiridoid glycosides (IGs), an important group of plant defense compounds, in three species of honeysuckle, Lonicera morrowii A. Gray, Lonicera tatarica L., and their hybrid Lonicera×bella Zabel. (Caprifoliaceae), all of which are considered invasive in various parts of North America. Hybrid genotypes had a diversity of IGs inherited from both parent species, as well as one component not detected in either parent. All three species were similar in that overall concentrations of IGs were significantly higher in fruits than in leaves, and several compounds that were major components of fruits were never found in leaves. However, specific patterns of quantitative distribution among leaves, unripe fruits, and ripe fruits differed among the three species, with a relatively higher allocation to fruits in the hybrid species than for either parent. These patterns likely have important consequences for plant interactions with antagonistic herbivores and pathogens as well as mutualistic seed dispersers, and thus the potential invasiveness of hybrid and parental species in their introduced range. Methods established here for quantitative analysis of IGs will allow for the exploration of many compelling research questions related to the evolutionary ecology and invasion biology of these and other related species in the genus Lonicera.
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Affiliation(s)
- Susan R Whitehead
- Ecology and Evolutionary Biology and Museum of Natural History, University of Colorado at Boulder, UCB 334, Boulder, CO 80309, USA.
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23
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Stoepler TM, Rehill B. Forest habitat, not leaf phenotype, predicts late-season folivory ofQuercus albasaplings. Funct Ecol 2012. [DOI: 10.1111/j.1365-2435.2012.02033.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Teresa M. Stoepler
- Department of Biological Sciences; The George Washington University; 2023 G St. NW, Suite 340; Washington; DC; 20052; USA
| | - Brian Rehill
- Department of Chemistry; United States Naval Academy; 572M Holloway Road; Annapolis; MD; 21402; USA
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Relative importance of genetic, ontogenetic, induction, and seasonal variation in producing a multivariate defense phenotype in a foundation tree species. Oecologia 2012; 170:695-707. [PMID: 22652923 DOI: 10.1007/s00442-012-2344-6] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Accepted: 04/18/2012] [Indexed: 10/28/2022]
Abstract
Plant adaptations for defense against herbivory vary both among species and among genotypes. Moreover, numerous forms of within-plant variation in defense, including ontogeny, induction, and seasonal gradients, allow plants to avoid expending resources on defense when herbivores are absent. We used an 18-year-old cottonwood common garden composed of Populus fremontii, Populus angustifolia, and their naturally occurring F(1) hybrids (collectively referred to as "cross types") to quantify and compare the relative influences of three hierarchical levels of variation (between cross types, among genotypes, and within individual genotypes) on univariate and multivariate phytochemical defense traits. Within genotypes, we evaluated ontogeny, induction (following cottonwood leaf beetle herbivory), and seasonal variation. We compared the effect sizes of each of these sources of variation on the plant defense phenotype. Three major patterns emerged. First, we observed significant differences in concentrations of defense phytochemicals among cross types, and/or among genotypes within cross types. Second, we found significant genetic variation for within-plant differences in phytochemical defenses: (a) based on ontogeny, levels of constitutive phenolic glycosides were nearly three times greater in the mature zone than in the juvenile zone within one cottonwood cross type, but did not significantly differ within another cross type; (b) induced levels of condensed tannins increased up to 65 % following herbivore damage within one cottonwood cross type, but were not significantly altered in another cross type; and (c) concentrations of condensed tannins tended to increase across the season, but did not do so across all cross types. Third, our estimates of effect size demonstrate that the magnitude of within-plant variation in a phytochemical defense can rival the magnitude of differences in defense among genotypes and/or cross types. We conclude that, in cottonwood and likely other plant species, multiple forms of within-individual variation have the potential to substantially influence ecological and evolutionary processes.
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25
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Evans LM, Clark JS, Whipple AV, Whitham TG. The relative influences of host plant genotype and yearly abiotic variability in determining herbivore abundance. Oecologia 2011; 168:483-9. [PMID: 21918874 DOI: 10.1007/s00442-011-2108-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Accepted: 06/29/2011] [Indexed: 11/29/2022]
Abstract
Both plant genotype and yearly abiotic variation affect herbivore population sizes, but long-term data have rarely been used to contrast the relative contributions of each. Using a hierarchical Bayesian model, we directly compare effects of these two factors on the population size of a common herbivore, Aceria parapopuli, on Populus angustifolia × fremontii F(1) hybrid trees growing in a common garden across 8 years. Several patterns emerged. First, the Bayesian posterior estimates of tree genotype effects on mite gall number ranged from 0.0043 to 229 on a linear scale. Second, year effect sizes across 8 years of study ranged from 0.133 to 1.895. Third, in comparing the magnitudes of genotypic versus yearly variation, we found that genotypic variation was over 130 times greater than variation among years. Fourth, precipitation in the previous year negatively affected gall abundances, but was minimal compared to tree genotype effects. These findings demonstrate the relative importance of tree genotypic variation in determining herbivore population size. However, given the demonstrated sensitivity of cottonwoods to drought, the loss of individual tree genotypes from an altered climate would have catastrophic impacts on mites that are dependent upon these genotypes for their survival.
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Affiliation(s)
- Luke M Evans
- Department of Biological Sciences, The Environmental Genetics and Genomics Laboratory and Merriam-Powell Center for Environmental Research, Northern Arizona University, PO Box 5640, Flagstaff, AZ 86011, USA.
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26
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Barbehenn RV, Peter Constabel C. Tannins in plant-herbivore interactions. PHYTOCHEMISTRY 2011; 72:1551-65. [PMID: 21354580 DOI: 10.1016/j.phytochem.2011.01.040] [Citation(s) in RCA: 369] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 01/26/2011] [Accepted: 01/31/2011] [Indexed: 05/07/2023]
Abstract
Tannins are the most abundant secondary metabolites made by plants, commonly ranging from 5% to 10% dry weight of tree leaves. Tannins can defend leaves against insect herbivores by deterrence and/or toxicity. Contrary to early theories, tannins have no effect on protein digestion in insect herbivores. By contrast, in vertebrate herbivores tannins can decrease protein digestion. Tannins are especially prone to oxidize in insects with high pH guts, forming semiquinone radicals and quinones, as well as other reactive oxygen species. Tannin toxicity in insects is thought to result from the production of high levels of reactive oxygen species. Tannin structure has an important effect on biochemical activity. Ellagitannins oxidize much more readily than do gallotannins, which are more oxidatively active than most condensed tannins. The ability of insects to tolerate ingested tannins comes from a variety of biochemical and physical defenses in their guts, including surfactants, high pH, antioxidants, and a protective peritrophic envelope that lines the midgut. Most work on the ecological roles of tannins has been correlative, e.g., searching for negative associations between tannins and insect performance. A greater emphasis on manipulative experiments that control tannin levels is required to make further progress on the defensive functions of tannins. Recent advances in the use of molecular methods has permitted the production of tannin-overproducing transgenic plants and a better understanding of tannin biosynthetic pathways. Many research areas remain in need of further work, including the effects of different tannin types on different types of insects (e.g., caterpillars, grasshoppers, sap-sucking insects).
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Affiliation(s)
- Raymond V Barbehenn
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109-1048, USA
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28
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Scioneaux AN, Schmidt MA, Moore MA, Lindroth RL, Wooley SC, Hagerman AE. Qualitative variation in proanthocyanidin composition of Populus species and hybrids: genetics is the key. J Chem Ecol 2010; 37:57-70. [PMID: 21116841 DOI: 10.1007/s10886-010-9887-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2010] [Revised: 11/04/2010] [Accepted: 11/12/2010] [Indexed: 11/25/2022]
Abstract
The literature on proanthocyanidins (tannins) in ecological systems is dominated by quantitative studies. Despite evidence that the qualitative characteristics (subunit type, polymer chain length) of these complex polyphenolics are important determinants of biological activity, little is known about genetic and environmental controls on the type of proanthocyanidins produced by plants. We tested the hypothesis that genetics, season, developmental stage, and environment determine proanthocyanidin qualitative characteristics by using four Populus "cross types" (narrowleaf [P. angustifolia], Fremont [P. fremontii], F1 hybrids, and backcrosses to narrowleaf). We used thiolysis and HPLC analysis to characterize the proanthocyanidins, and found that genetics strongly control composition. The narrowleaf plants accumulate mixed procyanidin/prodelphinidins with average composition epicatechin(11)-epigallocatechin(8)-catechin(2)-catechin((terminal)). Backcross genotypes produce mixed procyanidin/prodelphinidins similar to narrowleaf, while Fremont makes procyanidin dimers, and the F1 plants contain procyanidin heptamers. Less striking effects were noted for genotype × environment, while season and developmental zone had little effect on proanthocyanidin composition or chain length. We discuss the metabolic and ecological consequences of differences in condensed tannin qualitative traits.
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Affiliation(s)
- Ashley N Scioneaux
- Department of Chemistry & Biochemistry, Miami University, Oxford, OH 45056, USA
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29
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Schweitzer JA, Fischer DG, Rehill BJ, Wooley SC, Woolbright SA, Lindroth RL, Whitham TG, Zak DR, Hart SC. Forest gene diversity is correlated with the composition and function of soil microbial communities. POPUL ECOL 2010. [DOI: 10.1007/s10144-010-0252-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Jennifer A. Schweitzer
- Department of Ecology and Evolutionary BiologyUniversity of Tennessee37996KnoxvilleTNUSA
| | - Dylan G. Fischer
- Environmental Studies ProgramThe Evergreen State College98505OlympiaWAUSA
| | | | - Stuart C. Wooley
- Department of Biological SciencesCalifornia State University‐Stanislaus95382TurlockCAUSA
| | - Scott A. Woolbright
- Department of Biological Sciences, Merriam‐Powell Center for Environmental ResearchNorthern Arizona University86011FlagstaffAZUSA
| | | | - Thomas G. Whitham
- Department of Biological Sciences, Merriam‐Powell Center for Environmental ResearchNorthern Arizona University86011FlagstaffAZUSA
| | - Donald R. Zak
- Department of Ecology and Evolutionary Biology, School of Natural Resources and EnvironmentUniversity of Michigan48109Ann ArborMIUSA
| | - Stephen C. Hart
- School of Natural Sciences, Sierra Nevada Research InstituteUniversity of California95343MercedCAUSA
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30
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Eisenberg DM, Harris ESJ, Littlefield BA, Cao S, Craycroft JA, Scholten R, Bayliss P, Fu Y, Wang W, Qiao Y, Zhao Z, Chen H, Liu Y, Kaptchuk T, Hahn WC, Wang X, Roberts T, Shamu CE, Clardy J. Developing a library of authenticated Traditional Chinese Medicinal (TCM) plants for systematic biological evaluation--rationale, methods and preliminary results from a Sino-American collaboration. Fitoterapia 2010; 82:17-33. [PMID: 21108995 DOI: 10.1016/j.fitote.2010.11.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Accepted: 11/10/2010] [Indexed: 10/18/2022]
Abstract
While the popularity of and expenditures for herbal therapies (aka "ethnomedicines") have increased globally in recent years, their efficacy, safety, mechanisms of action, potential as novel therapeutic agents, cost-effectiveness, or lack thereof, remain poorly defined and controversial. Moreover, published clinical trials evaluating the efficacy of herbal therapies have rightfully been criticized, post hoc, for their lack of quality assurance and reproducibility of study materials, as well as a lack of demonstration of plausible mechanisms and dosing effects. In short, clinical botanical investigations have suffered from the lack of a cohesive research strategy which draws on the expertise of all relevant specialties. With this as background, US and Chinese co-investigators with expertise in Traditional Chinese Medicine (TCM), botany, chemistry and drug discovery, have jointly established a prototype library consisting of 202 authenticated medicinal plant and fungal species that collectively represent the therapeutic content of the majority of all commonly prescribed TCM herbal prescriptions. Currently housed at Harvard University, the library consists of duplicate or triplicate kilogram quantities of each authenticated and processed species, as well as "detanninized" extracts and sub-fractions of each mother extract. Each species has been collected at 2-3 sites, each separated geographically by hundreds of miles, with precise GPS documentation, and authenticated visually and chemically prior to testing for heavy metals and/or pesticides contamination. An explicit decision process has been developed whereby samples with the least contamination were selected to undergo ethanol extraction and HPLC sub-fractionation in preparation for high throughput screening across a broad array of biological targets including cancer biology targets. As envisioned, the subfractions in this artisan collection of authenticated medicinal plants will be tested for biological activity individually and in combinations (i.e., "complex mixtures") consistent with traditional ethnomedical practice. This manuscript summarizes the rationale, methods and preliminary "proof of principle" for the establishment of this prototype, authenticated medicinal plant library. It is hoped that these methods will foster scientific discoveries with therapeutic potential and enhance efforts to systematically evaluate commonly used herbal therapies worldwide.
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Affiliation(s)
- David M Eisenberg
- Osher Research Center, Division for Research and Education in Complementary and Integrative Medical Therapies, Harvard Medical School, Boston, MA 02115, USA.
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31
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Genung MA, Schweitzer JA, Úbeda F, Fitzpatrick BM, Pregitzer CC, Felker-Quinn E, Bailey JK. Genetic variation and community change - selection, evolution, and feedbacks. Funct Ecol 2010. [DOI: 10.1111/j.1365-2435.2010.01797.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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32
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Preparation of an Acid Butanol Standard from Fresh Apples. J Chem Ecol 2010; 36:453-60. [DOI: 10.1007/s10886-010-9784-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Revised: 03/05/2010] [Accepted: 03/24/2010] [Indexed: 11/25/2022]
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33
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Soils as agents of selection: feedbacks between plants and soils alter seedling survival and performance. Evol Ecol 2010. [DOI: 10.1007/s10682-010-9363-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Holeski LM, Kearsley MJC, Whitham TG. Separating ontogenetic and environmental determination of resistance to herbivory in cottonwood. Ecology 2010; 90:2969-73. [PMID: 19967853 DOI: 10.1890/08-2378.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We used narrowleaf cottonwood, Populus angustifolia, and the gall-forming aphid, Pemphigus betae, to determine the extent to which ontogenetic variation in resistance to herbivory is due to endogenous, stable genetic influences. In a three-year common garden trial using ramets propagated from the top, middle, and bottom of mature trees, we found that the resistance of trees to aphids was significantly higher in top vs. bottom source ramets, supporting the hypothesis of a stable, genetically programmed component to aphid resistance. The magnitude of ontogenetically based variation in resistance within an individual tree is comparable to the genetic variation in resistance among narrowleaf cottonwood genotypes or populations found in other studies. These ontogenetic-based findings have the potential to alter ecological interactions and evolutionary trajectories of plant-herbivore interactions.
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Affiliation(s)
- Liza M Holeski
- Department of Entomology, University of Wisconsin, Madison, Wisconsin 53706, USA.
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35
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Bridgeland WT, Beier P, Kolb T, Whitham TG. A conditional trophic cascade: Birds benefit faster growing trees with strong links between predators and plants. Ecology 2010; 91:73-84. [DOI: 10.1890/08-1821.1] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Payyavula RS, Babst BA, Nelsen MP, Harding SA, Tsai CJ. Glycosylation-mediated phenylpropanoid partitioning in Populus tremuloides cell cultures. BMC PLANT BIOLOGY 2009; 9:151. [PMID: 20040108 PMCID: PMC2808312 DOI: 10.1186/1471-2229-9-151] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2009] [Accepted: 12/29/2009] [Indexed: 05/08/2023]
Abstract
BACKGROUND Phenylpropanoid-derived phenolic glycosides (PGs) and condensed tannins (CTs) comprise large, multi-purpose non-structural carbon sinks in Populus. A negative correlation between PG and CT concentrations has been observed in several studies. However, the molecular mechanism underlying the relationship is not known. RESULTS Populus cell cultures produce CTs but not PGs under normal conditions. Feeding salicyl alcohol resulted in accumulation of salicins, the simplest PG, in the cells, but not higher-order PGs. Salicin accrual reflected the stimulation of a glycosylation response which altered a number of metabolic activities. We utilized this suspension cell feeding system as a model for analyzing the possible role of glycosylation in regulating the metabolic competition between PG formation, CT synthesis and growth. Cells accumulated salicins in a dose-dependent manner following salicyl alcohol feeding. Higher feeding levels led to a decrease in cellular CT concentrations (at 5 or 10 mM), and a negative effect on cell growth (at 10 mM). The competition between salicin and CT formation was reciprocal, and depended on the metabolic status of the cells. We analyzed gene expression changes between controls and cells fed with 5 mM salicyl alcohol for 48 hr, a time point when salicin accumulation was near maximum and CT synthesis was reduced, with no effect on growth. Several stress-responsive genes were up-regulated, suggestive of a general stress response in the fed cells. Salicyl alcohol feeding also induced expression of genes associated with sucrose catabolism, glycolysis and the Krebs cycle. Transcript levels of phenylalanine ammonia lyase and most of the flavonoid pathway genes were reduced, consistent with down-regulated CT synthesis. CONCLUSIONS Exogenous salicyl alcohol was readily glycosylated in Populus cell cultures, a process that altered sugar utilization and phenolic partitioning in the cells. Using this system, we identified candidate genes for glycosyltransferases that may mediate the glycosylation, and for transporters that mediate the subcellular compartmentalization of sugars and phenolic glycosides. The suspension cells appear to represent a facile system for dissecting the regulation of phenolic carbon partitioning, and in turn, its effects on growth in Populus.
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Affiliation(s)
- Raja S Payyavula
- School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, 30602, USA
- Current address: United States Department of Agriculture, Agricultural Research Services, Prosser, WA 99350, USA
| | - Benjamin A Babst
- School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, 30602, USA
| | - Matthew P Nelsen
- School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA
- Current address: Committee on Evolutionary Biology, University of Chicago, Chicago, IL 60637, USA
| | - Scott A Harding
- School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, 30602, USA
| | - Chung-Jui Tsai
- School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI 49931, USA
- Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, 30602, USA
- Department of Genetics, University of Georgia, Athens, GA, 30602, USA
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37
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The role of plant resistance and tolerance to herbivory in mediating the effects of introduced herbivores. Biol Invasions 2009. [DOI: 10.1007/s10530-009-9630-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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38
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A test of the latitudinal defense hypothesis: herbivory, tannins and total phenolics in four North American tree species. Ecol Res 2008. [DOI: 10.1007/s11284-008-0541-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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39
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From Genes to Ecosystems: The Genetic Basis of Condensed Tannins and Their Role in Nutrient Regulation in a Populus Model System. Ecosystems 2008. [DOI: 10.1007/s10021-008-9173-9] [Citation(s) in RCA: 148] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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40
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Schweitzer JA, Bailey JK, Fischer DG, LeRoy CJ, Lonsdorf EV, Whitham TG, Hart SC. PLANT–SOIL–MICROORGANISM INTERACTIONS: HERITABLE RELATIONSHIP BETWEEN PLANT GENOTYPE AND ASSOCIATED SOIL MICROORGANISMS. Ecology 2008; 89:773-81. [DOI: 10.1890/07-0337.1] [Citation(s) in RCA: 259] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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41
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O'Reilly-Wapstra JM, Humphreys JR, Potts BM. Stability of genetic-based defensive chemistry across life stages in a Eucalyptus species. J Chem Ecol 2007; 33:1876-84. [PMID: 17924167 DOI: 10.1007/s10886-007-9366-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2007] [Accepted: 09/10/2007] [Indexed: 11/26/2022]
Abstract
Defensive chemistry is a key plant fitness trait, and the investigation of the expression of plant secondary metabolites across life stages is important in understanding the lifetime evolutionary selection pressures on a plant. The expression of genetic-based differences in foliar defensive chemistry, known to influence mammalian herbivore preferences, was studied across two contrasting life phases of the heteroblastic tree, Eucalyptus globulus. With plants from different subraces of E. globulus growing in a field trial, we compared the levels of seven chemical constituents in adult and juvenile foliage from related coppiced plants. Defensive chemistry was generally higher in more vulnerable coppice foliage than adult foliage. Significant, genetic-based differences among subraces were detected for two key defensive chemicals, a sideroxylonal and a macrocarpal, and these differences were stable across life phases. In contrast, significant differences among subraces in adult leaf condensed tannins were not evident in the coppice because of the absence of this group of tannins in this foliage. These findings lend support to hypotheses that suggest condensed tannins may have evolved for reasons other than mammalian herbivore defense.
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Affiliation(s)
- Julianne M O'Reilly-Wapstra
- School of Plant Science and Cooperative Research Centre for Forestry, University of Tasmania, Private Bag 55, Hobart, Tasmania 7001, Australia.
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42
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Wimp GM, Wooley S, Bangert RK, Young WP, Martinsen GD, Keim P, Rehill B, Lindroth RL, Whitham TG. Plant genetics predicts intra-annual variation in phytochemistry and arthropod community structure. Mol Ecol 2007; 16:5057-69. [PMID: 17927708 DOI: 10.1111/j.1365-294x.2007.03544.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
With the emerging field of community genetics, it is important to quantify the key mechanisms that link genetics and community structure. We studied cottonwoods in common gardens and in natural stands and examined the potential for plant chemistry to be a primary mechanism linking plant genetics and arthropod communities. If plant chemistry drives the relationship between plant genetics and arthropod community structure, then several predictions followed. We would find (i) the strongest correlation between plant genetic composition and chemical composition; (ii) an intermediate correlation between plant chemical composition and arthropod community composition; and (iii) the weakest relationship between plant genetic composition and arthropod community composition. Our results supported our first prediction: plant genetics and chemistry had the strongest correlation in the common garden and the wild. Our results largely supported our second prediction, but varied across space, seasonally, and according to arthropod feeding group. Plant chemistry played a larger role in structuring common garden arthropod communities relative to wild communities, free-living arthropods relative to leaf and stem modifiers, and early-season relative to late-season arthropods. Our results did not support our last prediction, as host plant genetics was at least as tightly linked to arthropod community structure as plant chemistry, if not more so. Our results demonstrate the consistency of the relationship between plant genetics and biodiversity. Additionally, plant chemistry can be an important mechanism by which plant genetics affects arthropod community composition, but other genetic-based factors are likely involved that remain to be measured.
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Affiliation(s)
- G M Wimp
- Department of Biology, Georgetown University, Washington, DC 20057, USA.
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43
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Abstract
Mimulus guttatus (yellow monkeyflower) frequently produce glandular trichomes, a trait that may resist herbivory. Constitutive production of trichomes is variable both within and among populations of M. guttatus and most of this variation is genetic. This study demonstrates that damage on early leaves can induce increased trichome production on later leaves, a plastic response that is likely adaptive. Moreover, this study shows that this induction can be maternally transmitted, increasing trichome density in progeny before they experience herbivory. This transgenerational response must involve a yet undescribed epigenetic mechanism. These experiments also show genetic variation among plants in the capacity for both within and between plant generation induction. Despite the clear evolutionary importance of variation in constitutive and induced herbivory-resistance traits, few other studies have noted genetic variation in both within a plant species.
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Affiliation(s)
- L M Holeski
- Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS, USA.
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Woolbright SA, Difazio SP, Yin T, Martinsen GD, Zhang X, Allan GJ, Whitham TG, Keim P. A dense linkage map of hybrid cottonwood (Populus fremontii × P. angustifolia) contributes to long-term ecological research and comparison mapping in a model forest tree. Heredity (Edinb) 2007; 100:59-70. [PMID: 17895905 DOI: 10.1038/sj.hdy.6801063] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Cottonwoods are foundation riparian species, and hybridization among species is known to produce ecological effects at levels higher than the population, including effects on dependent species, communities and ecosystems. Because these patterns result from increased genetic variation in key cottonwood traits, novel applications of genetic tools (for example, QTL mapping) could be used to place broad-scale ecological research into a genomic perspective. In addition, linkage maps have been produced for numerous species within the genus, and, coupled with the recent publication of the Populus genome sequence, these maps present a unique opportunity for genome comparisons in a model system. Here, we conducted linkage analyses in order to (1) create a platform for QTL and candidate gene studies of ecologically important traits, (2) create a framework for chromosomal-scale perspectives of introgression in a natural population, and (3) enhance genome-wide comparisons using two previously unmapped species. We produced 246 backcross mapping (BC(1)) progeny by crossing a naturally occurring F(1) hybrid (Populus fremontii x P. angustifolia) to a pure P. angustifolia from the same population. Linkage analysis resulted in a dense linkage map of 541 AFLP and 111 SSR markers distributed across 19 linkage groups. These results compared favorably with other Populus linkage studies, and addition of SSR loci from the poplar genome project provided coarse alignment with the genome sequence. Preliminary applications of the data suggest that our map represents a useful framework for applying genomic research to ecological questions in a well-studied system, and has enhanced genome-wide comparisons in a model tree.
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Affiliation(s)
- S A Woolbright
- Department of Biological Sciences, Environmental Genetics and Genomics (EnGGen) Facility, Northern Arizona University, Flagstaff, AZ, USA.
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45
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Lindroth RL, Donaldson JR, Stevens MT, Gusse AC. Browse Quality in Quaking Aspen (Populus tremuloides): Effects of Genotype, Nutrients, Defoliation, and Coppicing. J Chem Ecol 2007; 33:1049-64. [PMID: 17404817 DOI: 10.1007/s10886-007-9281-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2006] [Accepted: 03/12/2007] [Indexed: 10/23/2022]
Abstract
The consequences of interactions among genetic, ontogenetic, and environmental factors for the quality of winter-dormant tissues as food for browsing herbivores is poorly understood. We conducted two sequential common garden studies to assess the impacts of intraspecific genetic variation, nutrient availability, prior defoliation, and ontogenetic stage on the chemical quality of winter-dormant tissue in quaking aspen (Populus tremuloides Michx.). In the first study, saplings of 12 aspen genotypes were grown under low and high soil nutrient conditions, with or without two successive seasons of defoliation. Quantity and quality of current year's twig growth were assessed. Twig production varied among genotypes and declined under low nutrient availability, but showed little response to prior defoliation. Chemical quality of sapling twigs varied substantially among genotypes, and in response to nutrient availability and prior defoliation. Overall, browse quality improved (nitrogen levels increased while phenolic glycoside and condensed tannin levels decreased) after defoliation. Growth and chemical variables exhibited low to moderate clonal repeatability (broad sense heritability) values. Our second study employed the same 12 genotypes, grown under high-nutrient conditions and with or without two seasons of defoliation. The trees were coppiced to produce root sprouts, which were chemically assessed 1 yr later. Rejuvenation via coppicing led to increased levels of nitrogen, phenolic glycosides (salicortin), and tannins in root sprouts, and the magnitude of change varied among aspen genotypes. Signatures of defoliation nearly 2 yr earlier persisted in terms of elevated levels of phenolic glycosides in root sprouts of previously defoliated trees. Aspen forests likely present browsing herbivores with chemically heterogeneous environments because of the interactions of genetic, ontogenetic, and environmental factors that vary over space and time.
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Affiliation(s)
- Richard L Lindroth
- Department of Entomology, University of Wisconsin, Madison, WI 53706, USA.
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