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Voelker J, Mauleon R, Shepherd M. A terpene synthase supergene locus determines chemotype in Melaleuca alternifolia (tea tree). THE NEW PHYTOLOGIST 2023; 240:1944-1960. [PMID: 37737003 DOI: 10.1111/nph.19262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 08/22/2023] [Indexed: 09/23/2023]
Abstract
Leaf oil terpenes vary categorically in many plant populations, leading to discrete phenotypes of adaptive and economic significance, but for most species, a genetic explanation for the concerted fluctuation in terpene chemistry remains unresolved. To uncover the genetic architecture underlying multi-component terpene chemotypes in Melaleuca alternifolia (tea tree), a genome-wide association study was undertaken for 148 individuals representing all six recognised chemotypes. A number of single nucleotide polymorphisms in a genomic region of c. 400 kb explained large proportions of the variation in key monoterpenes of tea tree oil. The region contained a cluster of 10 monoterpene synthase genes, including four genes predicted to encode synthases for 1,8-cineole, terpinolene, and the terpinen-4-ol precursor, sabinene hydrate. Chemotype-dependent null alleles at some sites suggested structural variants within this gene cluster, providing a possible basis for linkage disequilibrium in this region. Genotyping in a separate domesticated population revealed that all alleles surrounding this gene cluster were fixed after artificial selection for a single chemotype. These observations indicate that a supergene accounts for chemotypes in M. alternifolia. A genetic model with three haplotypes, encompassing the four characterised monoterpene synthase genes, explained the six terpene chemotypes, and was consistent with available biparental cross-segregation data.
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Affiliation(s)
- Julia Voelker
- Faculty of Science and Engineering, Southern Cross University, Military Road, East Lismore, NSW, 2480, Australia
| | - Ramil Mauleon
- Faculty of Science and Engineering, Southern Cross University, Military Road, East Lismore, NSW, 2480, Australia
| | - Mervyn Shepherd
- Faculty of Science and Engineering, Southern Cross University, Military Road, East Lismore, NSW, 2480, Australia
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2
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Clancy MV, Mamin M, Flückiger G, Quijano-Medina T, Pérez-Niño B, Abdala-Roberts L, Turlings TCJ, Bustos-Segura C. Terpene chemotypes in Gossypium hirsutum (wild cotton) from the Yucatan Peninsula, Mexico. PHYTOCHEMISTRY 2023; 205:113454. [PMID: 36244403 DOI: 10.1016/j.phytochem.2022.113454] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 09/12/2022] [Accepted: 09/22/2022] [Indexed: 05/25/2023]
Abstract
Cultivated plants of Gossypium hirsutum Cav. (cotton) consistently emit low levels of volatile organic compounds, primarily mono- and sesquiterpenoids, which are produced and stored in pigment glands. In this study, we provide a comprehensive evaluation of the terpene profiles of wild G. hirsutum plants sourced from sites located throughout natural distribution of this species, thus providing the first in-depth assessment of the scope of its intraspecific chemotypic diversity. Chemotypic variation can potentially influence resistance to herbivory and diseases, or interact with abiotic stress such as extreme temperatures. Under controlled environmental conditions, plants were grown from seeds of sixteen G. hirsutum populations collected along the coastline of the Yucatan Peninsula, which is its likely centre of origin. We found high levels of intraspecific diversity in the terpene profiles of the plants. Two distinct chemotypes were identified: one chemotype contained higher levels of the monoterpenes γ-terpinene, limonene, α-thujene, α-terpinene, terpinolene, and p-cymene, while the other chemotype was distinguished by higher levels of α- and β-pinene. The distribution of chemotypes followed a geographic gradient from west to east, with an increasing frequency of the former chemotype. Concurrent analysis of maternal plants revealed that chemotypes in wild G. hirsutum are highly heritable.
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Affiliation(s)
- Mary V Clancy
- University of Neuchâtel, Institute of Biology, Fundamental and Applied Research in Chemical Ecology, Rue Emile-Argand 11, CH-2000, Neuchâtel, Switzerland
| | - Marine Mamin
- University of Neuchâtel, Institute of Biology, Fundamental and Applied Research in Chemical Ecology, Rue Emile-Argand 11, CH-2000, Neuchâtel, Switzerland
| | - Galien Flückiger
- University of Neuchâtel, Institute of Biology, Fundamental and Applied Research in Chemical Ecology, Rue Emile-Argand 11, CH-2000, Neuchâtel, Switzerland
| | - Teresa Quijano-Medina
- Departamento de Ecología Tropical, Campus de Ciencias Biológicas y Agropecuarias, Universidad Autónoma de Yucatán, Km. 15.5 Carretera Mérida-Xtmakuil s/n, Mérida, Yucatán, 97200, Mexico
| | - Biiniza Pérez-Niño
- Departamento de Ecología Tropical, Campus de Ciencias Biológicas y Agropecuarias, Universidad Autónoma de Yucatán, Km. 15.5 Carretera Mérida-Xtmakuil s/n, Mérida, Yucatán, 97200, Mexico
| | - Luis Abdala-Roberts
- Departamento de Ecología Tropical, Campus de Ciencias Biológicas y Agropecuarias, Universidad Autónoma de Yucatán, Km. 15.5 Carretera Mérida-Xtmakuil s/n, Mérida, Yucatán, 97200, Mexico
| | - Ted C J Turlings
- University of Neuchâtel, Institute of Biology, Fundamental and Applied Research in Chemical Ecology, Rue Emile-Argand 11, CH-2000, Neuchâtel, Switzerland.
| | - Carlos Bustos-Segura
- University of Neuchâtel, Institute of Biology, Fundamental and Applied Research in Chemical Ecology, Rue Emile-Argand 11, CH-2000, Neuchâtel, Switzerland
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Moffitt MC, Wong-Bajracharya J, Shuey LS, Park RF, Pegg GS, Plett JM. Both Constitutive and Infection-Responsive Secondary Metabolites Linked to Resistance against Austropuccinia psidii (Myrtle Rust) in Melaleuca quinquenervia. Microorganisms 2022; 10:383. [PMID: 35208838 PMCID: PMC8879604 DOI: 10.3390/microorganisms10020383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 12/10/2022] Open
Abstract
Austropuccinia psidii is a fungal plant pathogen that infects species within the Myrtaceae, causing the disease myrtle rust. Myrtle rust is causing declines in populations within natural and managed ecosystems and is expected to result in species extinctions. Despite this, variation in response to A. psidii exist within some species, from complete susceptibility to resistance that prevents or limits infection by the pathogen. Untargeted metabolomics using Ultra Performance Liquid Chromatography with Ion Mobility followed by analysis using MetaboAnalyst 3.0, was used to explore the chemical defence profiles of resistant, hypersensitive and susceptible phenotypes within Melaleuca quinquenervia during the early stages of A. psidii infection. We were able to identify three separate pools of secondary metabolites: (i) metabolites classified structurally as flavonoids that were naturally higher in the leaves of resistant individuals prior to infection, (ii) organoheterocyclic and carbohydrate-related metabolites that varied with the level of host resistance post-infection, and (iii) metabolites from the terpenoid pathways that were responsive to disease progression regardless of resistance phenotype suggesting that these play a minimal role in disease resistance during the early stages of colonization of this species. Based on the classes of these secondary metabolites, our results provide an improved understanding of key pathways that could be linked more generally to rust resistance with particular application within Melaleuca.
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Affiliation(s)
- Michelle C. Moffitt
- School of Science, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Johanna Wong-Bajracharya
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW 2753, Australia; (J.W.-B.); (J.M.P.)
- New South Wales Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Menangle, NSW 2568, Australia
| | - Louise S. Shuey
- Department of Agriculture and Fisheries, Queensland Government, Brisbane, QLD 4102, Australia; (L.S.S.); (G.S.P.)
| | - Robert F. Park
- The Plant Breeding Institute, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia;
| | - Geoff S. Pegg
- Department of Agriculture and Fisheries, Queensland Government, Brisbane, QLD 4102, Australia; (L.S.S.); (G.S.P.)
| | - Jonathan M. Plett
- Hawkesbury Institute for the Environment, Western Sydney University, Richmond, NSW 2753, Australia; (J.W.-B.); (J.M.P.)
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Manea A, Tabassum S, Fernandez Winzer L, Leishman MR. Susceptibility to the fungal plant pathogen Austropuccinia psidii is related to monoterpene production in Australian Myrtaceae species. Biol Invasions 2022. [DOI: 10.1007/s10530-021-02721-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
AbstractIn 2010, the fungal plant pathogen that causes Myrtle rust, Austropuccinia psidii, which is native to South America, was first detected in Australia and has since had significant impacts on several Australian Myrtaceae species. Despite this, our understanding of the role secondary metabolites play in plant susceptibility to A. psidii is limited. This study aimed to determine: (1) whether secondary metabolite (phenolics, terpenes) production is induced after A. psidii inoculation and if so, (2) how their production relates to A. psidii susceptibility. To test these aims, we selected seven Myrtaceae species that have a wide range of within-species variability in their susceptibility to A. psidii. We found that five of the study species significantly increased either their phenolic or sesquiterpene production post-inoculation suggesting their pre-inoculation secondary metabolite levels were not sufficient to combat A. psidii infection. The two species (Angophora costata and Corymbia citriodora) that did not increase their secondary metabolite production post-inoculation tended to have the greatest pre-inoculation production levels amongst the species. Interestingly, across all species, monoterpenes were the only secondary metabolite found to reduce plant susceptibility to A. psidii. This study contributes to our limited understanding of the role that secondary metabolites play in plant susceptibility to A. psidii. In light of these findings, future research should aim to identify biomarkers (e.g. individual chemical compounds) that confer resistance to A. psidii, so that individuals with these biomarkers can be utilised in commercial and conservation projects.
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Łukowski A, Jagiełło R, Robakowski P, Adamczyk D, Karolewski P. Adaptation of a simple method to determine the total terpenoid content in needles of coniferous trees. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 314:111090. [PMID: 34895553 DOI: 10.1016/j.plantsci.2021.111090] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 10/09/2021] [Indexed: 06/14/2023]
Abstract
In ecological research, quantitative methods are often used to measure the total content of metabolites groups (i.e., phenols, carbohydrates). Until recently, there has been no simple and effective method to determine the total terpenoid content with satisfactory repeatability and sensitivity. The procedure proposed by Ghorai et al. (2012) requires the use of fresh plant material. That may be problematic when experimental units are located far from a laboratory. Our goals were to optimize the procedure, and to find the threshold of misestimation using the procedure adjusted to work with dried material. Needles of Pinus sylvestris were used to test the effect of changes in drying, grinding, storage, and extraction on determined total terpenoid content. All applied changes in material storage and grinding decreased the quantity of the terpenoids in needles. Only air-dried and ball-milled material produced similar results to those obtained with fresh material - can be recommended if the fresh material unattainable. Air-dried material may be stored for up to three months, but it resulted in greater variation and then greater sample size is needed. Lower sample mass and solvent volume have no impact on accuracy. Shorter extraction time, oven-drying or microwaving leads to unreliability of measurements.
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Affiliation(s)
- Adrian Łukowski
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035, Kórnik, Poland; Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, Wojska Polskiego 71c, 60-625, Poznań, Poland.
| | - Radosław Jagiełło
- Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, Wojska Polskiego 71c, 60-625, Poznań, Poland
| | - Piotr Robakowski
- Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, Wojska Polskiego 71c, 60-625, Poznań, Poland
| | - Dawid Adamczyk
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035, Kórnik, Poland
| | - Piotr Karolewski
- Institute of Dendrology, Polish Academy of Sciences, Parkowa 5, 62-035, Kórnik, Poland
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Hassan E, Mostafiz MM, Iramu ET, George D, Lee KY. Evaluation of the Effect of Fungatol and Gamma-T-ol on the Emergence and Adult Parasitoid Survival of Mummies of Cotton Aphids Parasitized by Aphidius colemani. INSECTS 2021; 13:insects13010038. [PMID: 35055883 PMCID: PMC8778611 DOI: 10.3390/insects13010038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/11/2021] [Accepted: 12/27/2021] [Indexed: 11/22/2022]
Abstract
Simple Summary Biological control can be used as an alternative control measure to reduce pesticide resistance. Unfortunately, many biological control agents, such as natural enemies of pests, are susceptible to a broad spectrum of pesticides. This creates a potential problem when these two components are utilized together. Therefore, it is necessary to find alternatives that are not harmful to natural enemies but also have the potential to replace synthetic pesticides. Essential oils (EOs) are widely used in crop protection and organic agriculture. The EO formulations evaluated in this study are new botanical pesticides that play an important role in agriculture. EOs are available as an alternative to synthetic pesticides. Two blends (Fungatol and Gamma-T-ol) are mostly composed of Alpha Tops, and Gamma Tops were assessed for their effects on the aphid parasitoid Aphidius colemani in laboratory and glasshouse trials. According to the International Organization for Biological Control (IOBC) classification, they were found to be safe or only slightly toxic, making them potential candidates for introduction into an integrated pest control program for aphids. Abstract Beneficial insects play a major role in controlling pest populations. In sustainable agricultural production systems, control methods compatible with integrated pest management (IPM) are preferred over broad-spectrum pesticides. EOs from aromatic plants may provide a new and safe alternative to synthetic chemicals. In this research, the efficacy of Fungatol, Gamma-T-ol, Fungatol plus neem, and Gamma-T-ol plus neem was evaluated against Aphidius colemani Viereck (Hymenoptera: Braconidae; Aphidiidae), the parasitoid of the cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae). Under laboratory and greenhouse conditions, five different concentrations of each formulation were applied to parasitized mummies and adult parasitoids. Results for parasitoid emergence from aphid mummies sprayed with different concentrations of Fungatol, Gamma-T-ol, Fungatol plus neem, and Gamma-T-ol plus neem in the laboratory and glasshouse showed that the formulations did not adversely affect adult emergence as rates above 60% were observed. For residual toxicity tests done by exposing adult parasitoids to a fresh, dry biopesticide film sprayed on glass plates, less than 20% mortality was observed after 48 h of exposure. Adult longevity tests revealed that the highest concentrations of some of the formulations evaluated were slightly toxic to A. colemani. According to the IOBC rating, our results indicated that most of the tested concentrations for each formulation were harmless to A. colemani. Based on the above results, it may be proposed that the formulations evaluated in this study are potential botanical pesticide candidates for incorporation into an IPM program.
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Affiliation(s)
- Errol Hassan
- School of Agriculture and Food Sciences, The University of Queensland Gatton, Lawes, QLD 4343, Australia;
- Correspondence: ; Tel.: +61-(0)7-5460-1285
| | - Md Munir Mostafiz
- Division of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 41566, Korea; (M.M.M.); (K.-Y.L.)
| | | | - Doug George
- School of Agriculture and Food Sciences, The University of Queensland Gatton, Lawes, QLD 4343, Australia;
| | - Kyeong-Yeoll Lee
- Division of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 41566, Korea; (M.M.M.); (K.-Y.L.)
- Sustainable Agriculture Research Center, Kyungpook National University, Daegu 39061, Korea
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Hsieh J, Krause ST, Kainer D, Degenhardt J, Foley WJ, Külheim C. Characterization of terpene biosynthesis in Melaleuca quinquenervia and ecological consequences of terpene accumulation during myrtle rust infection. PLANT-ENVIRONMENT INTERACTIONS (HOBOKEN, N.J.) 2021; 2:177-193. [PMID: 37283700 PMCID: PMC10168048 DOI: 10.1002/pei3.10056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 05/20/2021] [Accepted: 05/25/2021] [Indexed: 06/08/2023]
Abstract
Plants use a wide array of secondary metabolites including terpenes as defense against herbivore and pathogen attack, which can be constitutively expressed or induced. Here, we investigated aspects of the chemical and molecular basis of resistance against the exotic rust fungus Austropuccinia psidii in Melaleuca quinquenervia, with a focus on terpenes. Foliar terpenes of resistant and susceptible plants were quantified, and we assessed whether chemotypic variation contributed to resistance to infection by A. psidii. We found that chemotypes did not contribute to the resistance and susceptibility of M. quinquenervia. However, in one of the chemotypes (Chemotype 2), susceptible plants showed higher concentrations of several terpenes including α-pinene, limonene, 1,8-cineole, and viridiflorol compared with resistant plants. Transcriptome profiling of these plants showed that several TPS genes were strongly induced in response to infection by A. psidii. Functional characterization of these TPS showed them to be mono- and sesquiterpene synthases producing compounds including 1,8-cineole, β-caryophyllene, viridiflorol and nerolidol. The expression of these TPS genes correlated with metabolite data in a susceptible plant. These results suggest the complexity of resistance mechanism regulated by M. quinquenervia and that modulation of terpenes may be one of the components that contribute to resistance against A. psidii.
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Affiliation(s)
- Ji‐Fan Hsieh
- Research School of BiologyThe Australian National UniversityCanberraACTAustralia
| | - Sandra T. Krause
- Institut für PharmazieMartin‐Luther Universität, Halle‐WittenbergHalleGermany
| | - David Kainer
- Research School of BiologyThe Australian National UniversityCanberraACTAustralia
- Center for BioEnergy InnovationBioscience DivisionOak Ridge National LaboratoriesOak RidgeTNUSA
| | - Jörg Degenhardt
- Institut für PharmazieMartin‐Luther Universität, Halle‐WittenbergHalleGermany
| | - William J. Foley
- Research School of BiologyThe Australian National UniversityCanberraACTAustralia
| | - Carsten Külheim
- Research School of BiologyThe Australian National UniversityCanberraACTAustralia
- College of Forest Resources and Environmental ScienceMichigan Technological UniversityHoughtonMIUSA
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Intra-Individual and Intraspecific Terpenoid Diversity in Erodium cicutarium. PLANTS 2021; 10:plants10081574. [PMID: 34451618 PMCID: PMC8398229 DOI: 10.3390/plants10081574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 07/25/2021] [Accepted: 07/26/2021] [Indexed: 11/17/2022]
Abstract
The chemodiversity between and within individuals of several plant species is remarkable and shaped by the local habitat environment and the genetic background. The forb Erodium cicutarium (Geraniaceae) is globally distributed and partly invasive. This paper hypothesizes a high intra-specific and inter-individual chemical diversity in this species and investigates this by comparing the concentration and diversity of terpenoid compounds in different plant parts, i.e., leaves, blossoms and fruits. Plants were grown from seeds, originating from native range Bavaria (BY), Germany, and invaded range California (CA), USA, populations. In total, 20 different terpenoids were found, which occurred in distinct combinations and the patterns clustered into groups of distinct chemotypes for all plant parts. Several of the chemotypes were specific to plants of one region. The terpenoid compositions of different plant parts within individuals were highly correlated. Chemodiversity was higher in reproductive plant parts compared to the leaves, and higher in plants from BY compared to CA. This study highlights the intra-specific and inter-individual chemodiversity in E. cicutarium, linked to its geographical origin, which may facilitate its invasion success but also calls for further investigation of the role of chemodiversity in invasive plants on interactions with the environment.
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Espinosa-García FJ, García-Rodríguez YM, Bravo-Monzón AE, Vega-Peña EV, Delgado-Lamas G. Implications of the foliar phytochemical diversity of the avocado crop Persea americana cv. Hass in its susceptibility to pests and pathogens. PeerJ 2021; 9:e11796. [PMID: 35070514 PMCID: PMC8759378 DOI: 10.7717/peerj.11796] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 06/25/2021] [Indexed: 11/20/2022] Open
Abstract
Phytochemical diversity (PD) can be considered as a defensive trait; it can operate through single plant secondary metabolites or usually as complex mixtures of them. We tested the more diversity-better defense hypothesis correlating the leaf plant secondary metabolites (PSMs) with the incidence of plant enemies on Hass avocado trees. We expected a negative correlation between the occurrence of plant enemies and PD metrics. Also, as intraspecific PSMs polymorphisms in plant populations are common, we studied the incidence of plant enemies on Hass avocado trees representing chemical variants (chemotypes). We expected a differential incidence of plant enemies among trees grouped by their mono and sesquiterpene + phenylpropanoid chemotypes. We analyzed foliar hexane extracts from 236 trees in 17 orchards by gas chromatography and for the incidence of red mite, thrips, whitefly, avocado branch borer, fruit rot, scab, and peduncle collar blight. The predicted negative correlation between the plant enemies’ incidence and the phytochemical metrics did not occur. To determine the relationship between enemy incidence and chemotypes we grouped the trees by cluster analysis using a matrix of PSMs in each tree. Most trees were grouped under four out of 23 chemotypes. Branch borers attacked trees of low-frequency chemotypes more frequently than trees with common chemotypes. The incidence of five plant enemies was different among the predominant chemotypes. The hypothesis of more diversity-better defense was not supported by the correlations between the phytochemical diversity and the incidence of pests and pathogens in Hass avocado orchards. Based on our results, we hypothesize that phytochemical diversity function as a defensive trait relies more on differentiation among individuals in a population than on the sole increase of chemical diversity. Also, the differential incidence of pests and pathogens on trees classified by their foliar chemotypes implies that these susceptibility or resistance markers represent potential useful tools for Hass avocado orchard pest management.
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Affiliation(s)
- Francisco J. Espinosa-García
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Michoacán, México
| | - Yolanda M. García-Rodríguez
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Michoacán, México
| | - Angel E. Bravo-Monzón
- Escuela Nacional de Estudios Superiores Mérida, Universidad Nacional Autónoma de México, Mérida, Yucatán, México
| | - Ernesto V. Vega-Peña
- Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autónoma de México, Morelia, Michoacán, México
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Boncan DAT, Tsang SS, Li C, Lee IH, Lam HM, Chan TF, Hui JH. Terpenes and Terpenoids in Plants: Interactions with Environment and Insects. Int J Mol Sci 2020; 21:E7382. [PMID: 33036280 PMCID: PMC7583029 DOI: 10.3390/ijms21197382] [Citation(s) in RCA: 140] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/01/2020] [Accepted: 10/01/2020] [Indexed: 02/07/2023] Open
Abstract
The interactions of plants with environment and insects are bi-directional and dynamic. Consequently, a myriad of mechanisms has evolved to engage organisms in different types of interactions. These interactions can be mediated by allelochemicals known as volatile organic compounds (VOCs) which include volatile terpenes (VTs). The emission of VTs provides a way for plants to communicate with the environment, including neighboring plants, beneficiaries (e.g., pollinators, seed dispersers), predators, parasitoids, and herbivores, by sending enticing or deterring signals. Understanding terpenoid distribution, biogenesis, and function provides an opportunity for the design and implementation of effective and efficient environmental calamity and pest management strategies. This review provides an overview of plant-environment and plant-insect interactions in the context of terpenes and terpenoids as important chemical mediators of these abiotic and biotic interactions.
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Affiliation(s)
- Delbert Almerick T. Boncan
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong;
- Center for Soybean Research of the State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Stacey S.K. Tsang
- Simon F.S. Li Marine Science Laboratory, The Chinese University of Hong Kong, Shatin, Hong Kong; (S.S.K.T.); (C.L.); (I.H.T.L.)
| | - Chade Li
- Simon F.S. Li Marine Science Laboratory, The Chinese University of Hong Kong, Shatin, Hong Kong; (S.S.K.T.); (C.L.); (I.H.T.L.)
| | - Ivy H.T. Lee
- Simon F.S. Li Marine Science Laboratory, The Chinese University of Hong Kong, Shatin, Hong Kong; (S.S.K.T.); (C.L.); (I.H.T.L.)
| | - Hon-Ming Lam
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong;
- Center for Soybean Research of the State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Ting-Fung Chan
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong;
- Center for Soybean Research of the State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Jerome H.L. Hui
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong;
- Center for Soybean Research of the State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
- Simon F.S. Li Marine Science Laboratory, The Chinese University of Hong Kong, Shatin, Hong Kong; (S.S.K.T.); (C.L.); (I.H.T.L.)
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Marsh KJ, Saraf I, Hocart CH, Youngentob K, Singh IP, Foley WJ. Occurrence and distribution of unsubstituted B-ring flavanones in Eucalyptus foliage. PHYTOCHEMISTRY 2019; 160:31-39. [PMID: 30682682 DOI: 10.1016/j.phytochem.2019.01.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 01/08/2019] [Accepted: 01/10/2019] [Indexed: 06/09/2023]
Abstract
A group of plant specialised metabolites (PSMs) collectively known as unsubstituted B-ring flavanones (UBFs) have previously been found in the foliage of some species from the genus Eucalyptus L'Hér. (Myrtaceae), specifically from the subgenus Eucalyptus (monocalypts). Captive feeding studies using artificial diets suggest that these compounds may potentially influence the feeding preferences of marsupial folivores, such as koalas. Understanding natural variation in the composition and concentration of UBFs in eucalypt foliage is a first step to deciding whether, through their effects on herbivory, they might have broader effects on ecosystem dynamics. We used ESI-LCMS/MS and HPLC to characterise and quantify UBFs in 351 individual trees from 25 monocalypt species. We found large variation in the total UBF concentration both between and within species. For example, the mean concentration of UBFs in Eucalyptus muelleriana was 0.2 mg g-1 dry wt, whereas it was 105.7 mg g-1 dry wt, with a range of 78.2-141.3 mg g-1 dry wt, in Eucalyptus mediocris. Different eucalypt species contained different subsets of ten UBFs, and three species showed potential chemotypic variation between individuals within species. Our results suggest that UBFs naturally vary between monocalypt species and individuals at concentrations that could realistically be expected to affect the feeding dynamics of marsupial eucalypt folivores. UBFs could be measured relatively rapidly and cheaply in future studies using near-infrared reflectance (NIR) spectroscopy, as we were able to successfully predict the total UBF concentration of samples from their NIR spectra, with an r2 value of 0.98 and a standard error of prediction (SEP) of 6.07. This work further solidifies NIR spectroscopy as a powerful tool enabling ecologists to analyse the chemical composition of large numbers of samples.
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Affiliation(s)
- Karen J Marsh
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia.
| | - Isha Saraf
- Department of Natural Products, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, 160062 Punjab, India
| | - Charles H Hocart
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia; School of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Long Shuo Rd, Wei Yang District, Xi'an, Shaanxi 710021, People's Republic of China
| | - Kara Youngentob
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Inder-Pal Singh
- Department of Natural Products, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, 160062 Punjab, India
| | - William J Foley
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
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12
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Liao M, Yang QQ, Xiao JJ, Huang Y, Zhou LJ, Hua RM, Cao HQ. Toxicity of Melaleuca alternifolia essential oil to the mitochondrion and NAD +/NADH dehydrogenase in Tribolium confusum. PeerJ 2018; 6:e5693. [PMID: 30479882 PMCID: PMC6238770 DOI: 10.7717/peerj.5693] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 09/05/2018] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND In our previous study, Melaleuca alternifolia essential oil (EO) was considered to have an insecticidal effect by acting on the mitochondrial respiratory chain in insects. However, the mode of action is not fully understood. METHODS In this study, we investigated the insecticidal efficacy of the M. alternifolia EO against another major stored-product pest, Tribolium confusum Jacquelin du Val. Rarefaction and vacuolization of the mitochondrial matrix were evident in oil-fumigated T. confusum adults. RESULTS Alterations to the mitochondria confirmed the insecticidal effect of the M. alternifolia EO. Furthermore, comparative transcriptome analysis of T. confusum using RNA-seq indicated that most of the differentially expressed genes were involved in insecticide detoxification and mitochondrial function. The biochemical analysis showed that the intracellular NAD+/NADH ratio is involved in the differential effect of the M. alternifolia EO. DISCUSSION These results led us to conclude that NAD+/NADH dehydrogenase may be the prime target site for the M. alternifolia EO in insects, leading to blocking of the mitochondrial respiratory chain.
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Affiliation(s)
- Min Liao
- School of Plant Protection, Anhui Agricultural University, Hefei, China
- Provincial Key Laboratory for Agri-Food Safety, Anhui Province, Anhui Agricultural University, Hefei, China
| | - Qian-Qian Yang
- School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Jin-Jing Xiao
- School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Yong Huang
- School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Li-Jun Zhou
- School of Plant Protection, Anhui Agricultural University, Hefei, China
| | - Ri-Mao Hua
- Provincial Key Laboratory for Agri-Food Safety, Anhui Province, Anhui Agricultural University, Hefei, China
| | - Hai-Qun Cao
- School of Plant Protection, Anhui Agricultural University, Hefei, China
- Provincial Key Laboratory for Agri-Food Safety, Anhui Province, Anhui Agricultural University, Hefei, China
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13
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Felipe LDO, Júnior WFDS, Araújo KCD, Fabrino DL. Lactoferrin, chitosan and Melaleuca alternifolia-natural products that show promise in candidiasis treatment. Braz J Microbiol 2018; 49:212-219. [PMID: 29132828 PMCID: PMC5913821 DOI: 10.1016/j.bjm.2017.05.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 04/03/2017] [Accepted: 05/26/2017] [Indexed: 02/06/2023] Open
Abstract
The evolution of microorganisms resistant to many medicines has become a major challenge for the scientific community around the world. Motivated by the gravity of such a situation, the World Health Organization released a report in 2014 with the aim of providing updated information on this critical scenario. Among the most worrying microorganisms, species from the genus Candida have exhibited a high rate of resistance to antifungal drugs. Therefore, the objective of this review is to show that the use of natural products (extracts or isolated biomolecules), along with conventional antifungal therapy, can be a very promising strategy to overcome microbial multiresistance. Some promising alternatives are essential oils of Melaleuca alternifolia (mainly composed of terpinen-4-ol, a type of monoterpene), lactoferrin (a peptide isolated from milk) and chitosan (a copolymer from chitin). Such products have great potential to increase antifungal therapy efficacy, mitigate side effects and provide a wide range of action in antifungal therapy.
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Affiliation(s)
| | | | | | - Daniela Leite Fabrino
- Universidade Federal de São João del-Rei/Campus Alto Paraopeba, Minas Gerais, MG, Brazil
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14
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Foliar Terpene Chemotypes and Herbivory Determine Variation in Plant Volatile Emissions. J Chem Ecol 2018; 44:51-61. [PMID: 29376212 DOI: 10.1007/s10886-017-0919-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 11/05/2017] [Accepted: 12/18/2017] [Indexed: 01/14/2023]
Abstract
Plants that synthesize and store terpenes in specialized cells accumulate large concentrations of these compounds while avoiding autotoxicity. Stored terpenes may influence the quantity and profile of volatile compounds that are emitted into the environment and the subsequent role of those volatiles in mediating the activity of herbivores. The Australian medicinal tea tree, Melaleuca alternifolia, occurs as several distinct terpene chemotypes. We studied the profile of its terpene emissions to understand how variations in stored foliar terpenes influenced emissions, both constitutive and when damaged either by herbivores or mechanically. We found that foliar chemistry influenced differences in the composition of terpene emissions, but those emissions were minimal in intact plants. When plants were damaged by herbivores or mechanically, the emissions were greatly increased and the composition corresponded to the constitutive terpenes and the volatility of each compound, suggesting the main origin of emissions is the stored terpenes and not de novo biosynthesized volatiles. However, herbivores modified the composition of the volatile emissions in only one chemotype, probably due to the oxidative metabolism of 1,8-cineole by the beetles. We also tested whether the foliar terpene blend acted as an attractant for the specialized leaf beetles Paropsisterna tigrina and Faex sp. and a parasitoid fly, Anagonia zentae. None of these species responded to extracts of young leaves in an olfactometer, so we found no evidence that these species use plant odor cues for host location in laboratory conditions.
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15
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Padovan A, Keszei A, Hassan Y, Krause ST, Köllner TG, Degenhardt J, Gershenzon J, Külheim C, Foley WJ. Four terpene synthases contribute to the generation of chemotypes in tea tree (Melaleuca alternifolia). BMC PLANT BIOLOGY 2017; 17:160. [PMID: 28978322 PMCID: PMC5628445 DOI: 10.1186/s12870-017-1107-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 09/27/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Terpene rich leaves are a characteristic of Myrtaceae. There is significant qualitative variation in the terpene profile of plants within a single species, which is observable as "chemotypes". Understanding the molecular basis of chemotypic variation will help explain how such variation is maintained in natural populations as well as allowing focussed breeding for those terpenes sought by industry. The leaves of the medicinal tea tree, Melaleuca alternifolia, are used to produce terpinen-4-ol rich tea tree oil, but there are six naturally occurring chemotypes; three cardinal chemotypes (dominated by terpinen-4-ol, terpinolene and 1,8-cineole, respectively) and three intermediates. It has been predicted that three distinct terpene synthases could be responsible for the maintenance of chemotypic variation in this species. RESULTS We isolated and characterised the most abundant terpene synthases (TPSs) from the three cardinal chemotypes of M. alternifolia. Functional characterisation of these enzymes shows that they produce the dominant compounds in the foliar terpene profile of all six chemotypes. Using RNA-Seq, we investigated the expression of these and 24 additional putative terpene synthases in young leaves of all six chemotypes of M. alternifolia. CONCLUSIONS Despite contributing to the variation patterns observed, variation in gene expression of the three TPS genes is not enough to explain all variation for the maintenance of chemotypes. Other candidate terpene synthases as well as other levels of regulation must also be involved. The results of this study provide novel insights into the complexity of terpene biosynthesis in natural populations of a non-model organism.
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Affiliation(s)
- Amanda Padovan
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, 2601 Australia
| | - Andras Keszei
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, 2601 Australia
| | - Yasmin Hassan
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, 2601 Australia
| | - Sandra T. Krause
- Institute of Pharmacy, Martin Luther University, Hoher Weg 8, 06120 Halle, Germany
| | - Tobias G. Köllner
- Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany
| | - Jörg Degenhardt
- Institute of Pharmacy, Martin Luther University, Hoher Weg 8, 06120 Halle, Germany
| | - Jonathan Gershenzon
- Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany
| | - Carsten Külheim
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, 2601 Australia
| | - William J. Foley
- Division of Ecology and Evolution, Research School of Biology, The Australian National University, Canberra, 2601 Australia
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16
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Bustos-Segura C, Padovan A, Kainer D, Foley WJ, Külheim C. Transcriptome analysis of terpene chemotypes of Melaleuca alternifolia across different tissues. PLANT, CELL & ENVIRONMENT 2017; 40:2406-2425. [PMID: 28771760 DOI: 10.1111/pce.13048] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 07/25/2017] [Accepted: 07/26/2017] [Indexed: 06/07/2023]
Abstract
Plant chemotypes or chemical polymorphisms are defined by discrete variation in secondary metabolites within a species. This variation can have consequences for ecological interactions or the human use of plants. Understanding the molecular basis of chemotypic variation can help to explain how variation of plant secondary metabolites is controlled. We explored the transcriptomes of the 3 cardinal terpene chemotypes of Melaleuca alternifolia in young leaves, mature leaves, and stem and compared transcript abundance to variation in the constitutive profile of terpenes. Leaves from chemotype 1 plants (dominated by terpinen-4-ol) show a similar pattern of gene expression when compared to chemotype 5 plants (dominated by 1,8-cineole). Only terpene synthases in young leaves were differentially expressed between these chemotypes, supporting the idea that terpenes are mainly synthetized in young tissue. Chemotype 2 plants (dominated by terpinolene) show a greater degree of differential gene expression compared to the other chemotypes, which might be related to the isolation of plant populations that exhibit this chemotype and the possibility that the terpinolene synthase gene in M. alternifolia was derived by introgression from a closely related species, Melaleuca trichostachya. By using multivariate analyses, we were able to associate terpenes with candidate terpene synthases.
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Affiliation(s)
- Carlos Bustos-Segura
- Division of Evolution and Ecology, Research School of Biology, The Australian National University, Canberra, 2601, Australian Capital Territory, Australia
- Laboratory of Evolutionary Entomology, Institute of Biology, University of Neuchatel, Neuchatel, 2000, Switzerland
| | - Amanda Padovan
- Division of Evolution and Ecology, Research School of Biology, The Australian National University, Canberra, 2601, Australian Capital Territory, Australia
| | - David Kainer
- Division of Evolution and Ecology, Research School of Biology, The Australian National University, Canberra, 2601, Australian Capital Territory, Australia
| | - William J Foley
- Division of Evolution and Ecology, Research School of Biology, The Australian National University, Canberra, 2601, Australian Capital Territory, Australia
| | - Carsten Külheim
- Division of Evolution and Ecology, Research School of Biology, The Australian National University, Canberra, 2601, Australian Capital Territory, Australia
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17
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Shepherd M, Savins D, Dowell A, Morrow S, Allen G, Southwell I. Ecotype Variation of Methyl Eugenol Content in Tea Tree (Melaleuca alternifolia and Melaleuca linariifolia). Chem Biodivers 2017; 14. [PMID: 28749029 DOI: 10.1002/cbdv.201700278] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 07/24/2017] [Indexed: 11/07/2022]
Abstract
Methyl eugenol is a natural phenylpropanoid compound found in a wide range of plants used for food, flavouring, cosmetics, and health-care. As a suspected rodent carcinogen, methyl eugenol may also be harmful to humans when present in significant concentrations. Consequently, its level has been restricted in some foodstuffs and cosmetics for some markets. In order to assess the potential to breed uniformly low methyl eugenol cultivars for an essential oil crop, tea tree, the source of 'Oil of Melaleuca, terpinene-4-ol type', we examine levels in individual trees (n = 30) from two geographic regions and six terpene chemotypes. Overall, methyl eugenol levels were low in this species (Mean [SD] 354 [239] ppm, n = 30), much lower than levels predicted to be of toxicological concern. Within each chemotype, there was a lack of evidence for correlations between terpenoid constituents and methyl eugenol levels. Further support for the independence of methyl eugenol and terpene biosynthesis was evident from similar mean levels in selected (Mean [SD] 586 [339] ppm, n = 12) and undomesticated Melaleuca alternifolia trees (Mean [SD] 480 [299] ppm, n = 5) with terpinen-4-ol type oils. By contrast, methyl eugenol level varied by geographic origin and chemotype. Trees from the upland region, where there is a prevalence of terpinolene type trees, had lower average methyl eugenol levels than trees from the coastal region, where there is a prevalence of terpinen-4-ol and 1,8-cineole type trees.
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Affiliation(s)
- Mervyn Shepherd
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW, 2480, Australia
| | - Dale Savins
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW, 2480, Australia
| | - Ashley Dowell
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW, 2480, Australia
| | - Samantha Morrow
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW, 2480, Australia
| | - Gareth Allen
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW, 2480, Australia
| | - Ian Southwell
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW, 2480, Australia
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18
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Clancy MV, Zytynska SE, Senft M, Weisser WW, Schnitzler JP. Chemotypic variation in terpenes emitted from storage pools influences early aphid colonisation on tansy. Sci Rep 2016; 6:38087. [PMID: 27892539 PMCID: PMC5125103 DOI: 10.1038/srep38087] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 11/03/2016] [Indexed: 02/01/2023] Open
Abstract
Tansy plants (Tanacetum vulgare L.) exhibit high chemical variation, particularly in mono- and sesquiterpenes that are stored in specialised glands on the plant surface. In the present work we investigated the effects of terpene chemotypes on Metopeurum fuscoviride, an aphid species specialised on tansy, and their tending ants, at the field scale. Previous studies have chemotyped tansy by assessing dominant compounds; here we propose a method of chemotyping using all volatile compounds that are likely emitted from the storage glands. The analysis is based on two extraction methods: GC-MS analysis of leaf hexane extracts and SBSE analysis of headspace emissions. In an initial screening we identified the subset of compounds present in both chemical patterns, labelled as ‘compounds likely emitted from storage’. In a large field survey we could show that the putative chemotypic emission pattern from storage pools significantly affected the early aphid colonisation of tansy. Moreover, the statistical analyses revealed that minor compounds exerted a stronger influence on aphid and tending-ant presence than dominant compounds. Overall we demonstrated that within the enormous chemotypic variation of terpenes in tansy plants, chemical signatures of volatile terpenes can be related to the occurrence of insects on individual plants in the field.
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Affiliation(s)
- Mary V Clancy
- Helmholtz Zentrum München, Institute of Biochemical Plant Pathology, Research Unit Environmental Simulation (EUS), Neuherberg, Germany
| | - Sharon E Zytynska
- Technische Universität München, Terrestrial Ecology Research Group, Department of Ecology and Ecosystem Management, School of Life Sciences Weihenstephan, Freising, Germany
| | - Matthias Senft
- Technische Universität München, Terrestrial Ecology Research Group, Department of Ecology and Ecosystem Management, School of Life Sciences Weihenstephan, Freising, Germany
| | - Wolfgang W Weisser
- Technische Universität München, Terrestrial Ecology Research Group, Department of Ecology and Ecosystem Management, School of Life Sciences Weihenstephan, Freising, Germany
| | - Jörg-Peter Schnitzler
- Helmholtz Zentrum München, Institute of Biochemical Plant Pathology, Research Unit Environmental Simulation (EUS), Neuherberg, Germany
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