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Sobhy IS, Tamiru A, Chiriboga Morales X, Nyagol D, Cheruiyot D, Chidawanyika F, Subramanian S, Midega CAO, Bruce TJA, Khan ZR. Bioactive Volatiles From Push-Pull Companion Crops Repel Fall Armyworm and Attract Its Parasitoids. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.883020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Fall armyworm, Spodoptera frugiperda, is a serious invasive pest in Africa but “Push-Pull” companion cropping can substantially reduce infestation. Here, we elucidate the underpinning chemical ecology mechanisms. We hypothesized that companion crop volatiles repel herbivores (push) while attracting natural enemies (pull). Headspace volatiles collected from companion plants (Desmodium intortum, Desmodium uncinatum, Brachiaria Mulato II) were used in bioassays and electrophysiological recordings with S. frugiperda and parasitoid wasps. Insect populations, plant damage and herbivore parasitism were assessed in field plots. Coupled GC-electroantennogram (GC-EAG) recordings showed robust responses to certain aromatic and terpenoid volatile compounds. In wind tunnel bioassays, maize volatiles mixed with Desmodium volatiles were less attractive to moths than maize alone. In oviposition bioassays, S. frugiperda laid significantly fewer eggs on maize when Desmodium volatiles were present. Conversely, in an olfactometer bioassay, parasitoid wasps were attracted to the scent of both Desmodium spp. (intercrop) and the Brachiaria border crop. Our data provide evidence of the mechanisms underpinning reduced S. frugiperda infestation in the Push-Pull companion cropping system, i.e., volatiles from companion crops repel S. frugiperda while attracting its parasitoid natural enemies. These findings explain why Push-Pull field plots had fewer S. frugiperda larvae and lower crop damage than monocropped maize.
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Zhu J, Renzone G, Arena S, Dani FR, Paulsen H, Knoll W, Cambillau C, Scaloni A, Pelosi P. The Odorant-Binding Proteins of the Spider Mite Tetranychus urticae. Int J Mol Sci 2021; 22:ijms22136828. [PMID: 34202019 PMCID: PMC8269058 DOI: 10.3390/ijms22136828] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 06/21/2021] [Accepted: 06/22/2021] [Indexed: 11/16/2022] Open
Abstract
Spider mites are one of the major agricultural pests, feeding on a large variety of plants. As a contribution to understanding chemical communication in these arthropods, we have characterized a recently discovered class of odorant-binding proteins (OBPs) in Tetranychus urticae. As in other species of Chelicerata, the four OBPs of T. urticae contain six conserved cysteines paired in a pattern (C1-C6, C2-C3, C4-C5) differing from that of insect counterparts (C1-C3, C2-C5, C4-C6). Proteomic analysis uncovered a second family of OBPs, including twelve members that are likely to be unique to T. urticae. A three-dimensional model of TurtOBP1, built on the recent X-ray structure of Varroa destructor OBP1, shows protein folding different from that of insect OBPs, although with some common features. Ligand-binding experiments indicated some affinity to coniferyl aldehyde, but specific ligands may still need to be found among very large molecules, as suggested by the size of the binding pocket.
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Affiliation(s)
- Jiao Zhu
- Austrian Institute of Technology GmbH, Biosensor Technologies, Konrad-Lorenz Straße, 24, 3430 Tulln, Austria; (J.Z.); (W.K.)
- Faculty of Biology, Institute of Molecular Physiology, Johannes Gutenberg-Universität, 55099 Mainz, Germany;
| | - Giovanni Renzone
- Proteomics & Mass Spectrometry Laboratory, ISPAAM, National Research Council, 80147 Napoli, Italy; (G.R.); (S.A.); (A.S.)
| | - Simona Arena
- Proteomics & Mass Spectrometry Laboratory, ISPAAM, National Research Council, 80147 Napoli, Italy; (G.R.); (S.A.); (A.S.)
| | - Francesca Romana Dani
- Department of Biology, University of Firenze, Via Madonna del Piano 6, 50019 Sesto Fiorentino, Italy;
| | - Harald Paulsen
- Faculty of Biology, Institute of Molecular Physiology, Johannes Gutenberg-Universität, 55099 Mainz, Germany;
| | - Wolfgang Knoll
- Austrian Institute of Technology GmbH, Biosensor Technologies, Konrad-Lorenz Straße, 24, 3430 Tulln, Austria; (J.Z.); (W.K.)
- Department of Physics and Chemistry of Materials, Faculty of Medicine/Dental Medicine, Danube Private University, 3500 Krems, Austria
| | - Christian Cambillau
- Architecture et Fonction des Macromolécules Biologiques (UMR 7257), CNRS and Aix-Marseille Université, CDEX 09, 13288 Marseille, France;
| | - Andrea Scaloni
- Proteomics & Mass Spectrometry Laboratory, ISPAAM, National Research Council, 80147 Napoli, Italy; (G.R.); (S.A.); (A.S.)
| | - Paolo Pelosi
- Austrian Institute of Technology GmbH, Biosensor Technologies, Konrad-Lorenz Straße, 24, 3430 Tulln, Austria; (J.Z.); (W.K.)
- Correspondence:
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Parmezan TR, Brito Júnior SL, Carvalho KD, Aquino MD, Birkett M, Pickett J, Nunes EDO, Abdelnor RV, Campo CBH, Marcelino-Guimarães FC. Transcriptional profile of genes involved in the production of terpenes and glyceollins in response to biotic stresses in soybean. Genet Mol Biol 2020; 43:e20190388. [PMID: 33174975 PMCID: PMC7644969 DOI: 10.1590/1678-4685-gmb-2019-0388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 07/08/2020] [Indexed: 11/21/2022] Open
Abstract
Terpenes produced by plants comprise a diverse range of secondary metabolites, including volatile organic compounds (VOCs). Terpene VOC production may be altered after damage or by biological stimuli such as bacterial, fungal and insects, and subsequent triggering of plant defense responses. These VOCs originate in plants from two independent pathways: the mevalonate and the methylerythritol phosphate pathways, which utilize dimethylallyl and isopentenyl diphosphates to form the terpenoidal precursors. Phakopsora pachyrhizi fungi causes Asian soybean rust, limiting soybean production and resulting in losses of up to 80% if no control strategies are applied. By using a transcriptome datasets, we investigated the regulation of genes of the mevalonate pathway under different biotic stresses. We studied the impact of P. pachyrhizi infection in vivo expression profile of genes involved in terpenoid and glyceollin biosynthesis in genotypes harboring different resistance genes (Rpp), and across the infection cycle. In addition, we used UPLC and UPGC analysis to evaluate glyceollin and VOC production, respectively, to identify metabolites associated with soybean responses to pathogen infection. The regulation of soybean genes involved in terpene production was influenced by genotypes, depending on the Rpp gene, while glyceollin was induced in all genotypes. Furthermore, a sesquiterpene was identified as a potential marker associated with rust symptoms on soybean.
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Affiliation(s)
- Talitta Regina Parmezan
- Universidade Estadual de Londrina, Departamento de Bioquímica e Biotecnologia, Londrina, PR, Brazil
| | | | - Kenia de Carvalho
- Universidade Estadual de Londrina, Departamento de Genética e Biologia Molecular, Londrina, PR, Brazil
| | - Moisés de Aquino
- Empresa Brasileira de Pesquisa Agropecuária-EMBRAPA Soja, Londrina, PR, Brazil
| | - Michael Birkett
- Rothamsted Research, Biointeractions and Crop Protection Department, Harpenden, UK
| | - John Pickett
- Cardiff University, School of Chemistry, Wales, UK
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Dong X, Chaisiri K, Xia D, Armstrong SD, Fang Y, Donnelly MJ, Kadowaki T, McGarry JW, Darby AC, Makepeace BL. Genomes of trombidid mites reveal novel predicted allergens and laterally transferred genes associated with secondary metabolism. Gigascience 2018; 7:5160133. [PMID: 30445460 PMCID: PMC6275457 DOI: 10.1093/gigascience/giy127] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 10/18/2018] [Indexed: 12/21/2022] Open
Abstract
Background Trombidid mites have a unique life cycle in which only the larval stage is ectoparasitic. In the superfamily Trombiculoidea ("chiggers"), the larvae feed preferentially on vertebrates, including humans. Species in the genus Leptotrombidium are vectors of a potentially fatal bacterial infection, scrub typhus, that affects 1 million people annually. Moreover, chiggers can cause pruritic dermatitis (trombiculiasis) in humans and domesticated animals. In the Trombidioidea (velvet mites), the larvae feed on other arthropods and are potential biological control agents for agricultural pests. Here, we present the first trombidid mites genomes, obtained both for a chigger, Leptotrombidium deliense, and for a velvet mite, Dinothrombium tinctorium. Results Sequencing was performed using Illumina technology. A 180 Mb draft assembly for D. tinctorium was generated from two paired-end and one mate-pair library using a single adult specimen. For L. deliense, a lower-coverage draft assembly (117 Mb) was obtained using pooled, engorged larvae with a single paired-end library. Remarkably, both genomes exhibited evidence of ancient lateral gene transfer from soil-derived bacteria or fungi. The transferred genes confer functions that are rare in animals, including terpene and carotenoid synthesis. Thirty-seven allergenic protein families were predicted in the L. deliense genome, of which nine were unique. Preliminary proteomic analyses identified several of these putative allergens in larvae. Conclusions Trombidid mite genomes appear to be more dynamic than those of other acariform mites. A priority for future research is to determine the biological function of terpene synthesis in this taxon and its potential for exploitation in disease control.
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Affiliation(s)
- Xiaofeng Dong
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, United Kingdom.,Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, Suzhou 215123, China.,School of Life Sciences, Jiangsu Normal University, Xuzhou 221116, China.,Institute of Infection & Global Health, University of Liverpool, L3 5RF, United Kingdom
| | - Kittipong Chaisiri
- Institute of Infection & Global Health, University of Liverpool, L3 5RF, United Kingdom.,Faculty of Tropical Medicine, Mahidol University, Ratchathewi Bangkok 10400, Thailand
| | - Dong Xia
- Institute of Infection & Global Health, University of Liverpool, L3 5RF, United Kingdom.,The Royal Veterinary College, London NW1 0TU, United Kingdom
| | - Stuart D Armstrong
- Institute of Infection & Global Health, University of Liverpool, L3 5RF, United Kingdom
| | - Yongxiang Fang
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, United Kingdom
| | - Martin J Donnelly
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Tatsuhiko Kadowaki
- Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, Suzhou 215123, China
| | - John W McGarry
- Institute of Veterinary Science, University of Liverpool, Liverpool L3 5RP, United Kingdom
| | - Alistair C Darby
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, United Kingdom
| | - Benjamin L Makepeace
- Institute of Infection & Global Health, University of Liverpool, L3 5RF, United Kingdom
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Shimizu N, Sakata D, Schmelz EA, Mori N, Kuwahara Y. Biosynthetic pathway of aliphatic formates via a Baeyer-Villiger oxidation in mechanism present in astigmatid mites. Proc Natl Acad Sci U S A 2017; 114:2616-2621. [PMID: 28223501 PMCID: PMC5347546 DOI: 10.1073/pnas.1612611114] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Astigmatid mites depend on bioactive glandular secretions, pheromones, and defensive agents to mediate intra- and interspecies interactions. Aliphatic formates, such as (Z,Z)-8,11-heptadecadienyl formate (8,11-F17) and (Z)-8-heptadecenyl formate (8-F17), are rarely encountered natural products that are abundant in Sancassania sp. Sasagawa (Acari: Acaridae) mite secretions. Linoleic acid and oleic acid are predicted as key intermediates in the synthesis of the closely related aliphatic formates. To gain insight in this biosynthetic pathway, acarid mite feeding experiments were conducted using 13C-labeled precursors to precisely track incorporation. Analyses using 13C NMR spectroscopy demonstrated that the 13C-labeling pattern of the precursors was detectable on formates in exocrine secretions and likewise on fatty acids in total lipid pools. Curiously, the results demonstrated that the formates were biosynthesized without the dehomologation of corresponding fatty acids. Careful examination of the mass spectra from labeling experiments revealed that the carbonyl carbon of the formates is originally derived from the C-1 position of the fatty acids. Consistent with a Baeyer-Villiger oxidation reaction, labeling studies support the insertion of an oxygen atom between the carbonyl group and carbon chain. Empirical data support the existence of a Baeyer-Villiger monooxygenase responsible for the catalyzation of the Baeyer-Villiger oxidation. The predicted existence of a Baeyer-Villiger monooxygenase capable of converting aliphatic aldehydes to formates represents an exciting opportunity to expand the enzymatic toolbox available for controlled biochemical synthesis.
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Affiliation(s)
- Nobuhiro Shimizu
- Faculty of Bioenvironmental Science, Kyoto Gakuen University, Kameoka 621-8555, Japan;
| | - Daisuke Sakata
- Faculty of Bioenvironmental Science, Kyoto Gakuen University, Kameoka 621-8555, Japan
| | - Eric A Schmelz
- Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093-080
| | - Naoki Mori
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Yasumasa Kuwahara
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, Imizu, Toyama 939-0398, Japan
- Asano Active Enzyme Molecule Project, Exploratory Research for Advanced Technology, Japan Science and Technology Agency, Imizu, Toyama 939-0398, Japan
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Salicylic Acid Induces Changes in Mango Fruit that Affect Oviposition Behavior and Development of the Oriental Fruit Fly, Bactrocera dorsalis. PLoS One 2015; 10:e0139124. [PMID: 26422203 PMCID: PMC4589398 DOI: 10.1371/journal.pone.0139124] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 09/09/2015] [Indexed: 12/26/2022] Open
Abstract
The Oriental fruit fly, Bactrocera dorsalis (Hendel) is an important quarantine pest around the globe. Although measures for its control are implemented worldwide through IPM and male annihilation, there is little effect on their population. Hence, there is a need for new strategies to control this minacious pest. A strategy that has received negligible attention is the induction of ‘natural plant defenses’ by phytohormones. In this study, we investigated the effect of salicylic acid (SA) treatment of mango fruit (cv. Totapuri) on oviposition and larval development of B. dorsalis. In oviposition choice assays, gravid females laid significantly less eggs in SA treated compared to untreated fruit. Headspace volatiles collected from SA treated fruit were less attractive to gravid females compared to volatiles from untreated fruit. GC-MS analysis of the headspace volatiles from SA treated and untreated fruit showed noticeable changes in their chemical compositions. Cis-ocimene and 3-carene (attractants to B. dorsalis) were reduced in the headspace volatiles of treated fruit. Further, reduced pupae formation and adult emergence was observed in treated fruit compared to control. Increased phenol and flavonoid content was recorded in treated fruit. We also observed differential expression of anti-oxidative enzymes namely catalase (CAT), polyphenoloxidase (PPO) and peroxidase (POD). In summary, the results indicate that SA treatment reduced oviposition, larval development and adult emergence of B. dorsalis and suggest a role of SA in enhancing mango tolerance to B. dorsalis.
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Pheromonal Communication in the European House Dust Mite, Dermatophagoides pteronyssinus. INSECTS 2014; 5:639-50. [PMID: 26462831 PMCID: PMC4592581 DOI: 10.3390/insects5030639] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 07/18/2014] [Accepted: 07/30/2014] [Indexed: 11/16/2022]
Abstract
Despite the sanitary importance of the European house dust mite Dermatophagoides pteronyssinus (Trouessart, 1897), the pheromonal communication in this species has not been sufficiently studied. Headspace analysis using solid phase micro extraction (SPME) revealed that nerol, neryl formate, pentadecane, (6Z,9Z)-6,9-heptadecadiene, and (Z)-8-heptadecene are released by both sexes whereas neryl propionate was released by males only. Tritonymphs did not produce any detectable volatiles. In olfactometer experiments, pentadecane and neryl propionate were attractive to both sexes as well as to tritonymphs. (Z)-8-heptadecene was only attractive to male mites. Therefore it is discussed that pentadecane and neryl propionate are aggregation pheromones and (Z)-8-heptadecene is a sexual pheromone of the European house dust mite D. pteronyssinus. To study the potential use of pheromones in dust mite control, long-range olfactometer experiments were conducted showing that mites can be attracted to neryl propionate over distances of at least 50 cm. This indicates that mite pheromones might be useable to monitor the presence or absence of mites in the context of control strategies.
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Babikova Z, Gilbert L, Bruce T, Dewhirst SY, Pickett JA, Johnson D. Arbuscular mycorrhizal fungi and aphids interact by changing host plant quality and volatile emission. Funct Ecol 2013. [DOI: 10.1111/1365-2435.12181] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zdenka Babikova
- Institute of Biological and Environmental Sciences; University of Aberdeen; Cruickshank building St. Machar Drive Aberdeen AB24 3UU UK
- James Hutton Institute; Craigiebuckler Aberdeen AB15 8QH UK
- Rothamsted Research; Harpenden AL5 2JQ UK
| | - Lucy Gilbert
- James Hutton Institute; Craigiebuckler Aberdeen AB15 8QH UK
| | - Toby Bruce
- Rothamsted Research; Harpenden AL5 2JQ UK
| | | | | | - David Johnson
- Institute of Biological and Environmental Sciences; University of Aberdeen; Cruickshank building St. Machar Drive Aberdeen AB24 3UU UK
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Oluwafemi S, Dewhirst SY, Veyrat N, Powers S, Bruce TJA, Caulfield JC, Pickett JA, Birkett MA. Priming of Production in Maize of Volatile Organic Defence Compounds by the Natural Plant Activator cis-Jasmone. PLoS One 2013; 8:e62299. [PMID: 23840295 PMCID: PMC3694093 DOI: 10.1371/journal.pone.0062299] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Accepted: 03/22/2013] [Indexed: 01/05/2023] Open
Abstract
cis-Jasmone (CJ) is a natural plant product that activates defence against herbivores in model and crop plants. In this study, we investigated whether CJ could prime defence in maize, Zea mays, against the leafhopper, Cicadulina storeyi, responsible for the transmission of maize streak virus (MSV). Priming occurs when a pre-treatment, in this case CJ, increases the potency and speed of a defence response upon subsequent attack on the plant. Here, we tested insect responses to plant volatile organic compounds (VOCs) using a Y-tube olfactometer bioassay. Our initial experiments showed that, in this system, there was no significant response of the herbivore to CJ itself and no difference in response to VOCs collected from unexposed plants compared to CJ exposed plants, both without insects. VOCs were then collected from C. storeyi-infested maize seedlings with and without CJ pre-treatment. The bioassay revealed a significant preference by this pest for VOCs from infested seedlings without the CJ pre-treatment. A timed series of VOC collections and bioassays showed that the effect was strongest in the first 22 h of insect infestation, i.e. before the insects had themselves induced a change in VOC emission. Chemical analysis showed that treatment of maize seedlings with CJ, followed by exposure to C. storeyi, led to a significant increase in emission of the defensive sesquiterpenes (E)-(1R,9S)-caryophyllene, (E)-α-bergamotene, (E)-β-farnesene and (E)-4,8-dimethyl-1,3,7-nonatriene, known to act as herbivore repellents. The chemical analysis explains the behavioural effects observed in the olfactometer, as the CJ treatment caused plants to emit a blend of VOCs comprising more of the repellent components in the first 22 h of insect infestation than control plants. The speed and potency of VOC emission was increased by the CJ pre-treatment. This is the first indication that CJ can prime plants for enhanced production of defensive VOCs antagonist towards herbivores.
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Affiliation(s)
- Sunday Oluwafemi
- Department of Crop Production, Soil and Environmental Management, Bowen University, Iwo, Osun State, Nigeria
- Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Herts., United Kingdom
| | - Sarah Y. Dewhirst
- Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Herts., United Kingdom
| | - Nathalie Veyrat
- University of Neuchâtel, Institute of Biology, Neuchâtel, Switzerland
| | - Stephen Powers
- Biomathematics and Bioinformatics Department, Rothamsted Research, Harpenden, Herts., United Kingdom
| | - Toby J. A. Bruce
- Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Herts., United Kingdom
| | - John C. Caulfield
- Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Herts., United Kingdom
| | - John A. Pickett
- Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Herts., United Kingdom
| | - Michael A. Birkett
- Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Herts., United Kingdom
- * E-mail:
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The role of semiochemicals in short-range location of aggregation sites in Adalia bipunctata (Coleoptera, Coccinellidae). J Chem Ecol 2013; 39:591-601. [PMID: 23620127 DOI: 10.1007/s10886-013-0285-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2012] [Revised: 02/22/2013] [Accepted: 04/05/2013] [Indexed: 10/26/2022]
Abstract
To survive unfavorable periods, ladybird beetles form conspicuous aggregations in specific microsites, with these locations remaining the same year after year. This constancy of location leads to the hypothesis that semiochemicals are involved in the attraction and aggregation of ladybirds to the microsite. In this study, we identified two types of semiochemicals that could play key roles in the attraction and aggregation formation of the two-spotted ladybird, Adalia bipunctata. We first isolated and identified three alkylmethoxypyrazines from A. bipunctata and tested the behavioral responses of diapausing ladybirds to these chemicals in a four-way olfactometer. This revealed that 2-isobutyl-3-methoxypyrazine, on its own or as part of a two-component mixture with 2-isopropyl-3-methoxypyrazine, elicited a positive behavioral response, causing arrestment of diapausing A. bipunctata. As ladybirds are in contact with each other in aggregations, we investigated the role of cuticular hydrocarbons (CHCs) in driving the cohesion and maintenance of aggregation. When an extract of CHCs from diapausing ladybirds was deposited near an alkylmethoxypyrazine source, ladybirds spent more time in the vicinity of the source. We identified a set of CHCs specific to diapausing A. bipunctata. Alkylmethoxyyrazines and CHCs thus deliver information to diapausing ladybirds searching for an aggregation site, as well as mediating several other behaviors throughout the ladybird's life cycle. Chemical parsimony is discussed.
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Hegde M, Oliveira JN, da Costa JG, Loza-Reyes E, Bleicher E, Santana AEG, Caulfield JC, Mayon P, Dewhirst SY, Bruce TJA, Pickett JA, Birkett MA. Aphid antixenosis in cotton is activated by the natural plant defence elicitor cis-jasmone. PHYTOCHEMISTRY 2012; 78:81-8. [PMID: 22516741 DOI: 10.1016/j.phytochem.2012.03.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Revised: 02/22/2012] [Accepted: 03/05/2012] [Indexed: 05/24/2023]
Abstract
Upon insect herbivory, plants can release blends of volatile organic compounds (VOCs) that modify herbivore and natural enemy behaviour. We have shown recently that cotton, Gossypium hirsutum, emits a blend of defence VOCs that repels the cotton aphid, Aphis gossypii, upon herbivory by this notorious crop pest, including (Z)-3-hexenyl acetate, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), methyl salicylate and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT). In this study, we investigated changes in the defence VOC profile of G. hirsutum induced by the naturally-occurring plant elicitor cis-jasmone (CJ) and whether these changes modify the behaviour of A. gossypii. In four-arm olfactometer assays, VOCs from untreated plants were significantly attractive (P<0.05), whilst VOCs from CJ-treated plants were significantly repellent (P<0.05). The VOCs induced by CJ appeared to comprise (Z)-3-hexenyl acetate, DMNT, methyl salicylate and TMTT. In quantitative VOC collection studies, sustained release of DMNT and TMTT was observed in CJ-treated plants over a period of five days, with levels becoming statistically significantly higher than for control treated plants on the fifth day in most cases. Despite earlier indications, no statistically significant differences were observed in levels of (Z)-3-hexenyl acetate or methyl salicylate between CJ and control treatments on any day. Furthermore, DMNT and TMTT emissions from CJ-treated plants were further enhanced by subsequent addition of A. gossypii. CJ treatment induced statistically significantly higher DMNT and TMTT expression levels as early as day three, when A. gossypii was present. The results in this study show that CJ can induce the production of A. gossypii-induced VOCs from G. hirsutum, with potential for deployment in novel crop protection strategies.
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Affiliation(s)
- Mahabaleshwar Hegde
- Department of Agricultural Entomology, University of Agricultural Sciences, Dharwad, Pin-580005, Karnataka, India
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Khan MA, Jones I, Loza-Reyes E, Cameron MM, Pickett JA, Birkett MA. Interference in foraging behaviour of European and American house dust mites Dermatophagoides pteronyssinus and Dermatophagoides farinae (Acari: Pyroglyphidae) by catmint, Nepeta cataria (Lamiaceae). EXPERIMENTAL & APPLIED ACAROLOGY 2012; 57:65-74. [PMID: 22382713 DOI: 10.1007/s10493-012-9532-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Accepted: 02/03/2012] [Indexed: 05/31/2023]
Abstract
The European and American house dust mites, Dermatophagoides pteronyssinus and D. farinae, have a huge impact upon human health worldwide due to being the most important indoor trigger of atopic diseases such as asthma, rhinitis and atopic dermatitis. Preceding studies have shown that the behavioural response of house dust mites towards volatile chemicals from food sources can be assessed using a Y-tube olfactometer assay. In the current study, we used this assay to investigate, for the first time, the ability of the essential oil of the catmint plant, Nepeta cataria (Lamiaceae), known to repel other ectoparasites affecting human and animal health, to interfere with the attraction of D. pteronyssinus and D. farinae towards a standard food source (fish flakes). Two distinct chemotypes (A and B), enriched in the iridoid compounds (4aS,7S,7aR)-nepetalactone and (4aS,7S,7aS)-nepetalactone, and the sesquiterpene (E)-(1R,9S)-caryophyllene, were used. Initial assays with a hexane extract of fish flakes (FF extract) confirmed attraction of mites to this positive control (P < 0.001 and P < 0.05 for D. pteronyssinus and D. farinae respectively), but when presented in combination with either N. cataria chemotype, tested across a range of doses (10, 1, 0.1 and 0.01 μg), decreasing attraction of mites to their food source was observed as the dose augmented. Our study shows that N. cataria, enriched in iridoid nepetalactones and (E)-(1R,9S)-caryophyllene, exhibits potent repellent activity for house dust mites, and has the potential for deployment in control programmes based on interference with normal house dust mite behaviour.
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Affiliation(s)
- M A Khan
- Department of Biological Sciences, Gomal University, Dera Ismail Khan, Khyber-Pukhthoonkhwa, Pakistan
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Hegde M, Oliveira JN, da Costa JG, Bleicher E, Santana AEG, Bruce TJA, Caulfield J, Dewhirst SY, Woodcock CM, Pickett JA, Birkett MA. Identification of semiochemicals released by cotton, Gossypium hirsutum, upon infestation by the cotton aphid, Aphis gossypii. J Chem Ecol 2011; 37:741-50. [PMID: 21671083 DOI: 10.1007/s10886-011-9980-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 05/27/2011] [Accepted: 06/01/2011] [Indexed: 10/18/2022]
Abstract
The cotton aphid, Aphis gossypii (Homoptera: Aphididae), is increasing in importance as a pest worldwide since the introduction of Bt-cotton, which controls lepidopteran but not homopteran pests. The chemical ecology of interactions between cotton, Gossypium hirsutum (Malvaceae), A. gossypii, and the predatory lacewing Chrysoperla lucasina (Neuroptera: Chrysopidae), was investigated with a view to providing new pest management strategies. Behavioral tests using a four-arm (Pettersson) olfactometer showed that alate A. gossypii spent significantly more time in the presence of odor from uninfested cotton seedlings compared to clean air, but significantly less time in the presence of odor from A. gossypii infested plants. A. gossypii also spent significantly more time in the presence of headspace samples of volatile organic compounds (VOCs) obtained from uninfested cotton seedlings, but significantly less time with those from A. gossypii infested plants. VOCs from uninfested and A. gossypii infested cotton seedlings were analyzed by gas chromatography (GC) and coupled GC-mass spectrometry (GC-MS), leading to the identification of (Z)-3-hexenyl acetate, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), methyl salicylate, and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT), which were produced in larger amounts from A. gossypii infested plants compared to uninfested plants. In behavioral tests, A. gossypii spent significantly more time in the control (solvent) arms when presented with a synthetic blend of these four compounds, with and without the presence of VOCs from uninfested cotton. Coupled GC-electroantennogram (EAG) recordings with the lacewing C. lucasina showed significant antennal responses to VOCs from A. gossypii infested cotton, suggesting they have a role in indirect defense and indicating a likely behavioral role for these compounds for the predator as well as the aphid.
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Affiliation(s)
- Mahabaleshwar Hegde
- Department of Agricultural Entomology, University of Agricultural Sciences, Dharwad, Karnataka, India
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