1
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Ducker C, Baines C, Guy J, Euzébio Goulart Santana A, Pickett JA, Oldham NJ. A diterpene synthase from the sandfly Lutzomyia longipalpis produces the pheromone sobralene. Proc Natl Acad Sci U S A 2024; 121:e2322453121. [PMID: 38470919 PMCID: PMC10962984 DOI: 10.1073/pnas.2322453121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 02/06/2024] [Indexed: 03/14/2024] Open
Abstract
The phlebotomine sandfly, Lutzomyia longipalpis, a major vector of the Leishmania parasite, uses terpene pheromones to attract conspecifics for mating. Examination of the L. longipalpis genome revealed a putative terpene synthase (TPS), which-upon heterologous expression in, and purification from, Escherichia coli-yielded a functional enzyme. The TPS, termed LlTPS, converted geranyl diphosphate (GPP) into a mixture of monoterpenes with low efficiency, of which β-ocimene was the major product. (E,E)-farnesyl diphosphate (FPP) principally produced small amounts of (E)-β-farnesene, while (Z,E)- and (Z,Z)-FPP yielded a mixture of bisabolene isomers. None of these mono- and sesquiterpenes are known volatiles of L. longipalpis. Notably, however, when provided with (E,E,E)-geranylgeranyl diphosphate (GGPP), LlTPS gave sobralene as its major product. This diterpene pheromone is released by certain chemotypes of L. longipalpis, in particular those found in the Ceará state of Brazil. Minor diterpene components were also seen as products of the enzyme that matched those seen in a sandfly pheromone extract.
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Affiliation(s)
- Charles Ducker
- School of Chemistry, University of Nottingham, University Park, NottinghamNG7 2RD, United Kingdom
| | - Cameron Baines
- School of Chemistry, University of Nottingham, University Park, NottinghamNG7 2RD, United Kingdom
| | - Jennifer Guy
- School of Chemistry, University of Nottingham, University Park, NottinghamNG7 2RD, United Kingdom
| | | | - John A. Pickett
- School of Chemistry, Cardiff University, CardiffCF10 3AT, United Kingdom
| | - Neil J. Oldham
- School of Chemistry, University of Nottingham, University Park, NottinghamNG7 2RD, United Kingdom
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2
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Harvey DJ, Vuts J, Hooper A, Caulfield JC, Finch P, Woodcock CM, Gange AC, Chapman JW, Birkett MA, Pickett JA. Novel pheromone-mediated reproductive behaviour in the stag beetle, Lucanus cervus. Sci Rep 2024; 14:6037. [PMID: 38472207 DOI: 10.1038/s41598-024-55985-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 02/29/2024] [Indexed: 03/14/2024] Open
Abstract
The iconic European stag beetle (Lucanus cervus) (Coleoptera: Lucanidae) is one of the largest terrestrial beetles in Europe. Due to decreasing population numbers, thought to be a consequence of habitat loss, this beetle has become a near-threatened species across much of Europe, and a reliable monitoring system is required to measure its future population trends. As part of a programme aimed at conserving UK populations, we have investigated the chemical ecology of the beetle, with a view to developing an efficient semiochemical-based monitoring system. Such a scheme will be beneficial not only in the UK but across the European range of the species, where the beetle is of conservation concern. Here, we report on a surprising discovery of a male-produced pheromone, which provokes initial sexual receptivity in females, and which has not been previously identified in the animal kingdom. Furthermore, we assign sex pheromone function to a previously described female-specific compound.
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Affiliation(s)
- Deborah J Harvey
- Department of Biological Sciences, Royal Holloway University of London, Egham, TW20 0EX, UK.
| | - József Vuts
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - Antony Hooper
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - John C Caulfield
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - Paul Finch
- Department of Biological Sciences, Royal Holloway University of London, Egham, TW20 0EX, UK
| | - Christine M Woodcock
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - Alan C Gange
- Department of Biological Sciences, Royal Holloway University of London, Egham, TW20 0EX, UK
| | - Jason W Chapman
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, Cornwall, TR10 9FE, UK
| | - Michael A Birkett
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, AL5 2JQ, UK
| | - John A Pickett
- School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK.
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3
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Batume C, Mulongo IM, Ludlow R, Ssebaale J, Randerson P, Pickett JA, Mukisa IM, Scofield S. Evaluating repellence properties of catnip essential oil against the mosquito species Aedes aegypti using a Y-tube olfactometer. Sci Rep 2024; 14:2269. [PMID: 38280895 PMCID: PMC10821859 DOI: 10.1038/s41598-024-52715-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 01/23/2024] [Indexed: 01/29/2024] Open
Abstract
The mosquito species Aedes aegypti (L.) is known to act as a vector in the transmission of various diseases, including dengue fever and yellow fever. The use of insect repellents is one of precautionary measures used to mitigate the risk of these diseases in humans by reducing mosquito biting. Nepetalactone, a potent natural insect repellent primarily found in catnip (Nepeta cataria) essential oil, has emerged as a promising candidate for mosquito repellence. Here, we evaluated the potential of catnip essential oil (> 95% nepetalactone) for use as a mosquito repellent. Using a Y-tube olfactometer and human hands as an attractant, we analysed the effectiveness of catnip oil at repelling the mosquito species Aedes aegypti. We tested a range of dilutions of catnip essential oil and found that concentrations as low as 2% were effective at repelling > 70% of mosquitoes for between one and four hours after repellent application. These findings suggest that nepetalactone could potentially be used as a natural, effective alternative to synthetic mosquito repellents, thereby offering protection against vector-borne diseases.
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Affiliation(s)
- Charles Batume
- Department of Entomology, Uganda Virus Research Institute (UVRI), Entebbe, Uganda
| | | | | | | | | | | | - Ivan M Mukisa
- Department of Food Technology and Nutrition, Makerere University, Kampala, Uganda
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4
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Shi JH, Sun Z, Pickett JA, Hu XJ, Wang C, Liu L, Jin H, Abdelnabby H, Foba CN, Yang XQ, Chang XQ, Wang MQ. Unprecedented oviposition tactics avoid plant defences and reduce attack by parasitic wasps. Plant Cell Environ 2024; 47:308-318. [PMID: 37807627 DOI: 10.1111/pce.14731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/20/2023] [Accepted: 09/26/2023] [Indexed: 10/10/2023]
Abstract
Female insects oviposit in sites suitable for the development of their offspring. The Oriental armyworm, Mythimna separata is a serious pest of various crops including wheat and prefers to oviposit on withered leaves rather than on fresh plant material, which is surprisingly different from other insects. Studies here showed that this oviposition tactic enables avoidance of wheat defence against eggs and emerged larvae. Intact plants responded to M. separata egg deposition by releasing oviposition-induced plant volatiles including acetophenone, tetradecene and pentadecane after 24 h. Acetophenone was identified as quantitatively accounting for the attraction of the egg parasitoid wasp (Trichogramma chilonis). Leaf jasmonic acid levels significantly increased after M. separata laid eggs, and primed the plant against emerging larvae. In addition, newly emerged M. separata larvae adopted a fast crawling behaviour and starvation tolerance compared with other noctuid larvae, which enhanced the survival of larvae on the withered leaves. The elucidation of this complex and surprising plant-insect interaction provides the first explanation for a herbivore laying eggs on withered leaves to avoid natural enemies and live-plant defence against emerging larvae.
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Affiliation(s)
- Jin-Hua Shi
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Ze Sun
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - John A Pickett
- School of Chemistry, Cardiff University, Cardiff, Wales, UK
| | - Xin-Jun Hu
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Chao Wang
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Le Liu
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Huanan Jin
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Hazem Abdelnabby
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
- Department of Plant Protection, Faculty of Agriculture, Benha University, Banha, Qalyubia, Egypt
| | - Caroline Ngichop Foba
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
- College of Agriculture, Environmental and Human Sciences, Cooperative Extension, Lincoln University, Jefferson City, Missouri, USA
| | - Xue-Qing Yang
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Xiang-Qian Chang
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Man-Qun Wang
- Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
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5
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Ducker C, French S, Pathak M, Taylor H, Sainter A, Askem W, Dreveny I, Santana AEG, Pickett JA, Oldham NJ. Characterisation of geranylgeranyl diphosphate synthase from the sandfly Lutzomyia longipalpis. Insect Biochem Mol Biol 2023; 161:104001. [PMID: 37619821 DOI: 10.1016/j.ibmb.2023.104001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 08/02/2023] [Accepted: 08/20/2023] [Indexed: 08/26/2023]
Abstract
Leishmaniasis is a debilitating and often fatal neglected tropical disease. Males from sub-populations of the Leishmania-harbouring sandfly, Lutzomyia longipalpis, produce the diterpene sex and aggregation pheromone, sobralene, for which geranylgeranyl diphosphate (GGPP) is the likely isoprenoid precursor. We have identified a GGPP synthase (lzGGPPS) from L. longipalpis, which was recombinantly expressed in bacteria and purified for functional and kinetic analysis. In vitro enzymatic assays using LC-MS showed that lzGGPPS is an active enzyme, capable of converting substrates dimethylallyl diphosphate (DMAPP), (E)-geranyl diphosphate (GPP), (E,E)-farnesyl diphosphate (FPP) with co-substrate isopentenyl diphosphate (IPP) into (E,E,E)-GGPP, while (Z,E)-FPP was also accepted with low efficacy. Comparison of metal cofactors for lzGGPPS highlighted Mg2+ as most efficient, giving increased GGPP output when compared against other divalent metal ions tested. In line with previously characterised GGPPS enzymes, GGPP acted as an inhibitor of lzGGPPS activity. The molecular weight in solution of lzGGPPS was determined to be ∼221 kDa by analytical SEC, suggesting a hexameric assembly, as seen in the human enzyme, and representing the first assessment of GGPPS quaternary structure in insects.
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Affiliation(s)
- Charles Ducker
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Stanley French
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Monika Pathak
- School of Pharmacy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Harry Taylor
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Adam Sainter
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - William Askem
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Ingrid Dreveny
- School of Pharmacy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | | | - John A Pickett
- School of Chemistry, Cardiff University, Main Building, Park Pl, Cardiff, CF10 3AT, UK
| | - Neil J Oldham
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
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6
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Cascone P, Vuts J, Birkett MA, Rasmann S, Pickett JA, Guerrieri E. Small volatile lipophilic molecules induced belowground by aphid attack elicit a defensive response in neighbouring un-infested plants. Front Plant Sci 2023; 14:1154587. [PMID: 37426972 PMCID: PMC10326905 DOI: 10.3389/fpls.2023.1154587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 06/07/2023] [Indexed: 07/11/2023]
Abstract
In pioneering studies on plant-aphid interactions, we have observed that Vicia faba plants infested by aphids can transmit signals via the rhizosphere that induce aboveground defence in intact, neighbouring plants. The aphid parasitoid Aphidius ervi is significantly attracted towards intact broad bean plants grown in a hydroponic solution previously harbouring Acyrtosiphon pisum-infested plants. To identify the rhizosphere signal(s) possibly mediating this belowground plant-plant communication, root exudates were collected using Solid-Phase Extraction (SPE) from 10-day old A. pisum-infested and un-infested Vicia faba plants hydroponically grown. To verify the ability of these root exudates to trigger defence mechanisms against the aphids we added them to V. fabae plants grown in hydroponic solution, and tested these plants in the wind-tunnel bioassay to assess their attractiveness towards the aphids' parasitoids A. ervi. We identified three small volatile lipophilic molecules as plant defence elicitors: 1-octen-3-ol, sulcatone and sulcatol, in SPE extracts of A. pisum-infested broad bean plants. In wind tunnel assays, we recorded a significant increase in the attractiveness towards A. ervi of V. faba plants grown in hydroponic solution treated with these compounds, compared to plants grown in hydroponic treated with ethanol (control). Both 1-octen-3-ol and sulcatol have asymmetrically substituted carbon atoms at positions 3 and 2, respectively. Hence, we tested both their enantiomers alone or in mixture. We highlighted a synergistic effect on the level of attractiveness towards the parasitoid when testing the three compounds together in respect to the response recorded against them singly tested. These behavioural responses were supported by the characterization of headspace volatiles released by tested plants. These results shed new light on the mechanisms underlying plant-plant communication belowground and prompt the use of bio-derived semiochemicals for a sustainable protection of agricultural crops.
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Affiliation(s)
- Pasquale Cascone
- Institute for Sustainable Plant Protection, Consiglio Nazionale delle Ricerche, Portici, Napoli, Italy
| | - Jozsef Vuts
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Michael A. Birkett
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Sergio Rasmann
- Institute of Biology, University of Neuchatel, Neuchatel, Switzerland
| | - John A. Pickett
- School of Chemistry, Cardiff University, Cardiff, United Kingdom
| | - Emilio Guerrieri
- Institute for Sustainable Plant Protection, Consiglio Nazionale delle Ricerche, Portici, Napoli, Italy
- Institute for Sustainable Plant Protection, Consiglio Nazionale delle Ricerche, Torino, Italy
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7
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Cascone P, Vuts J, Birkett MA, Dewhirst S, Rasmann S, Pickett JA, Guerrieri E. L-DOPA functions as a plant pheromone for belowground anti-herbivory communication. Ecol Lett 2023; 26:460-469. [PMID: 36708055 DOI: 10.1111/ele.14164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 11/17/2022] [Accepted: 12/22/2022] [Indexed: 01/29/2023]
Abstract
While mechanisms of plant-plant communication for alerting neighbouring plants of an imminent insect herbivore attack have been described aboveground via the production of volatile organic compounds (VOCs), we are yet to decipher the specific components of plant-plant signalling belowground. Using bioassay-guided fractionation, we isolated and identified the non-protein amino acid l-DOPA, released from roots of Acyrtosiphon pisum aphid-infested Vicia faba plants, as an active compound in triggering the production of VOCs released aboveground in uninfested plants. In behavioural assays, we show that after contact with l-DOPA, healthy plants become highly attractive to the aphid parasitoid (Aphidius ervi), as if they were infested by aphids. We conclude that l-DOPA, originally described as a brain neurotransmitter precursor, can also enhance immunity in plants.
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Affiliation(s)
- Pasquale Cascone
- Institute for Sustainable Plant Protection, Consiglio Nazionale delle Ricerche, Naples, Italy
| | - Jozsef Vuts
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, UK
| | - Michael A Birkett
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, UK
| | | | - Sergio Rasmann
- Institute of Biology, University of Neuchatel, Neuchatel, Switzerland
| | | | - Emilio Guerrieri
- Institute for Sustainable Plant Protection, Consiglio Nazionale delle Ricerche, Naples, Italy
- Institute for Sustainable Plant Protection, Consiglio Nazionale delle Ricerche, Torino, Italy
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8
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Fuchs LK, Holland AH, Ludlow RA, Coates RJ, Armstrong H, Pickett JA, Harwood JL, Scofield S. Genetic Manipulation of Biosynthetic Pathways in Mint. Front Plant Sci 2022; 13:928178. [PMID: 35774811 PMCID: PMC9237610 DOI: 10.3389/fpls.2022.928178] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 05/24/2022] [Indexed: 06/15/2023]
Abstract
In recent years, the study of aromatic plants has seen an increase, with great interest from industrial, academic, and pharmaceutical industries. Among plants attracting increased attention are the Mentha spp. (mint), members of the Lamiaceae family. Mint essential oils comprise a diverse class of molecules known as terpenoids/isoprenoids, organic chemicals that are among the most diverse class of naturally plant derived compounds. The terpenoid profile of several Mentha spp. is dominated by menthol, a cyclic monoterpene with some remarkable biological properties that make it useful in the pharmaceutical, medical, cosmetic, and cleaning product industries. As the global market for Mentha essential oils increases, the desire to improve oil composition and yield follows. The monoterpenoid biosynthesis pathway is well characterised so metabolic engineering attempts have been made to facilitate this improvement. This review focuses on the Mentha spp. and attempts at altering the carbon flux through the biosynthetic pathways to increase the yield and enhance the composition of the essential oil. This includes manipulation of endogenous and heterologous biosynthetic enzymes through overexpression and RNAi suppression. Genes involved in the MEP pathway, the menthol and carvone biosynthetic pathways and transcription factors known to affect secondary metabolism will be discussed along with non-metabolic engineering approaches including environmental factors and the use of plant growth regulators.
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Affiliation(s)
- Lorenz K. Fuchs
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | | | | | - Ryan J. Coates
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Harvey Armstrong
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - John A. Pickett
- School of Chemistry, Cardiff University, Cardiff, United Kingdom
| | - John L. Harwood
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Simon Scofield
- School of Biosciences, Cardiff University, Cardiff, United Kingdom
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9
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Montgomery C, Vuts J, Woodcock CM, Withall DM, Birkett MA, Pickett JA, Robert D. Bumblebee electric charge stimulates floral volatile emissions in Petunia integrifolia but not in Antirrhinum majus. Naturwissenschaften 2021; 108:44. [PMID: 34519874 PMCID: PMC8440258 DOI: 10.1007/s00114-021-01740-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 03/19/2021] [Accepted: 06/07/2021] [Indexed: 11/25/2022]
Abstract
The timing of volatile organic compound (VOC) emission by flowering plants often coincides with pollinator foraging activity. Volatile emission is often considered to be paced by environmental variables, such as light intensity, and/or by circadian rhythmicity. The question arises as to what extent pollinators themselves provide information about their presence, in keeping with their long co-evolution with flowering plants. Bumblebees are electrically charged and provide electrical stimulation when visiting plants, as measured via the depolarisation of electric potential in the stem of flowers. Here we test the hypothesis that the electric charge of foraging bumblebees increases the floral volatile emissions of bee pollinated plants. We investigate the change in VOC emissions of two bee-pollinated plants (Petunia integrifolia and Antirrhinum majus) exposed to the electric charge typical of foraging bumblebees. P. integrifolia slightly increases its emissions of a behaviorally and physiologically active compound in response to visits by foraging bumblebees, presenting on average 121 pC of electric charge. We show that for P. integrifolia, strong electrical stimulation (600–700 pC) promotes increased volatile emissions, but this is not found when using weaker electrical charges more representative of flying pollinators (100 pC). Floral volatile emissions of A. majus were not affected by either strong (600–700 pC) or weak electric charges (100 pC). This study opens a new area of research whereby the electrical charge of flying insects may provide information to plants on the presence and phenology of their pollinators. As a form of electroreception, this sensory process would bear adaptive value, enabling plants to better ensure that their attractive chemical messages are released when a potential recipient is present.
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Affiliation(s)
- Clara Montgomery
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK.
| | - Jozsef Vuts
- Department of Biointeractions and Crop Protection, Rothamsted Research, West Common, Harpenden, AL5 2JQ, UK
| | - Christine M Woodcock
- Department of Biointeractions and Crop Protection, Rothamsted Research, West Common, Harpenden, AL5 2JQ, UK
| | - David M Withall
- Department of Biointeractions and Crop Protection, Rothamsted Research, West Common, Harpenden, AL5 2JQ, UK
| | - Michael A Birkett
- Department of Biointeractions and Crop Protection, Rothamsted Research, West Common, Harpenden, AL5 2JQ, UK
| | - John A Pickett
- School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK
| | - Daniel Robert
- School of Biological Sciences, Life Sciences Building, University of Bristol, 24 Tyndall Avenue, Bristol, BS8 1TQ, UK
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10
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Partridge SJ, Withall DM, Caulfield JC, Pickett JA, Stockman RA, Oldham NJ, Birkett MA. Iridoid Sex Pheromone Biosynthesis in Aphids Mimics Iridoid-Producing Plants. Chemistry 2021; 27:7231-7234. [PMID: 33851466 DOI: 10.1002/chem.202001356] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Indexed: 11/11/2022]
Abstract
Biosynthesis of (1R,4aS,7S,7aR)-nepetalactol (1) and (4aS,7S,7aR)-nepetalactone (2) in plants involves iridoid synthase (ISY), an atypical reductive cyclase that catalyses the reduction of 8-oxogeranial into the reactive enol of (S)-8-oxocitronellal, and cyclization of this enol intermediate, either non-enzymatically or by a nepetalactol-related short chain dehydrogenase enzyme (NEPS) that yields the nepetalactols. In this study, we investigated the biosynthesis in vivo of 1 and 2 in the pea aphid, Acyrthosiphon pisum, using a library of isotopically-labelled monoterpenoids as molecular probes. Topical application of deuterium-labelled probes synthesized from geraniol and nerol resulted in production of 2 H4 -lactol 1 and 2 H4 -lactone 2. However, deuterium incorporation was not evident using labelled probes synthesized from (S)-citronellol. These results suggest that iridoid biosynthesis in animals, specifically aphids, may follow a broadly similar route to that characterised for plants.
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Affiliation(s)
- Suzanne J Partridge
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK.,School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - David M Withall
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - John C Caulfield
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - John A Pickett
- School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK
| | - Robert A Stockman
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Neil J Oldham
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Michael A Birkett
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
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11
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Zhang Z, Liu Y, Portaluri V, Woodcock C, Pickett JA, Wang S, Zhou JJ. Chemical Identity and Functional Characterization of Semiochemicals That Promote the Interactions between Rice Plant and Rice Major Pest Nilaparvata lugens. J Agric Food Chem 2021; 69:4635-4644. [PMID: 33870696 DOI: 10.1021/acs.jafc.1c01135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The interaction between food crops and insect pests is mediated by semiochemicals emitted from host plants. These semiochemicals are natural behavioral modifiers and act on the insect olfactory system to locate hosts and preys. In this study, eight rice neuroactive semiochemicals were identified from rice varieties by GC-EAG and GC-MS. Their ability to modify rice pest behaviors was further studied as individual chemicals and physiologically relevant blend. The total amount of each semiochemical and the expression of their biosynthesis genes were significantly higher in pest susceptible variety than in pest-resistant variety and upregulated by the infestation of the pest Nilaparvata lugens (BPH). The semiochemicals emitted by uninfested plants (UIRVs) were more attractive to BPHs. Interestingly, the attractiveness of UIRVs was significantly reduced by the addition of the blend that mimics the natural composition of these semiochemicals emitted by infested plants (IRVs). Our study suggests a mechanism for the spread of pest infestation from infested plants to uninfested plants nearby. UIRVs initially serve as attractive signals to rice insect pests. The pest infestation changes the rice semiochemical profile to be less attractive or even repellent, which pushes further colonization to uninfested plants nearby. The identified semiochemicals can be used for crop protection based on a push-pull strategy.
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Affiliation(s)
- Zhenfei Zhang
- Plant Protection Research Institute, Guangdong Academy of Agricultural Sciences, 510640 Guangzhou, China
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden AL5 2JQ, U.K
| | - Yong Liu
- Plant Protection College, Shandong Agricultural University, 271018 Taian, China
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden AL5 2JQ, U.K
| | - Vincent Portaluri
- Eurofins Analytics France, Rue Pierre Adolphe Bobierre, 44323 Nantes, France
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden AL5 2JQ, U.K
| | - Christine Woodcock
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden AL5 2JQ, U.K
| | - John A Pickett
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden AL5 2JQ, U.K
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, U.K
| | - Senshan Wang
- Biocontrol Engineering Laboratory of Crop Diseases and Pests of Gansu Province, College of Plant Protection, Gansu Agricultural University, Lanzhou 730070, China
| | - Jing-Jiang Zhou
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden AL5 2JQ, U.K
- Biocontrol Engineering Laboratory of Crop Diseases and Pests of Gansu Province, College of Plant Protection, Gansu Agricultural University, Lanzhou 730070, China
- State Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Huaxi District, Guiyang 550025, China
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12
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Koczor S, Vuts J, Caulfield JC, Withall DM, Sarria A, Pickett JA, Birkett MA, Csonka ÉB, Tóth M. Sex Pheromone of the Alfalfa Plant Bug, Adelphocoris lineolatus: Pheromone Composition and Antagonistic Effect of 1-Hexanol (Hemiptera: Miridae). J Chem Ecol 2021; 47:525-533. [PMID: 33871786 PMCID: PMC8217015 DOI: 10.1007/s10886-021-01273-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 03/02/2021] [Accepted: 04/07/2021] [Indexed: 10/24/2022]
Abstract
The sex pheromone composition of alfalfa plant bugs, Adelphocoris lineolatus (Goeze), from Central Europe was investigated to test the hypothesis that insect species across a wide geographical area can vary in pheromone composition. Potential interactions between the pheromone and a known attractant, (E)-cinnamaldehyde, were also assessed. Coupled gas chromatography-electroantennography (GC-EAG) using male antennae and volatile extracts collected from females, previously shown to attract males in field experiments, revealed the presence of three physiologically active compounds. These were identified by coupled GC/mass spectrometry (GC/MS) and peak enhancement as hexyl butyrate, (E)-2-hexenyl butyrate and (E)-4-oxo-2-hexenal. A ternary blend of these compounds in a 5.4:9.0:1.0 ratio attracted male A. lineolatus in field trials in Hungary. Omission of either (E)-2-hexenyl-butyrate or (E)-4-oxo-2-hexenal from the ternary blend or substitution of (E)-4-oxo-2-hexenal by (E)-2-hexenal resulted in loss of activity. These results indicate that this Central European population is similar in pheromone composition to that previously reported for an East Asian population. Interestingly, another EAG-active compound, 1-hexanol, was also present in female extract. When 1-hexanol was tested in combination with the ternary pheromone blend, male catches were reduced. This compound showed a dose-response effect with small doses showing a strong behavioral effect, suggesting that 1-hexanol may act as a sex pheromone antagonist in A. lineolatus. Furthermore, when (E)-cinnamaldehyde was field tested in combination with the sex pheromone, there was no increase in male catch, but the combination attracted both males and females. Prospects for practical application are discussed.
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Affiliation(s)
- Sándor Koczor
- Plant Protection Institute, Centre for Agricultural Research, Eötvös Loránd Research Network (ELKH), H-1022 Herman Ottó u. 15, Budapest, Hungary.
| | - József Vuts
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - John C Caulfield
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - David M Withall
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - André Sarria
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK.,Biobab R&D, S. L. Calle Patones, s/n. Parcela 28.3 PI Ventorro del Cano, Alcorcón, 28925, Madrid, Spain
| | - John A Pickett
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK.,School of Chemistry, Cardiff University, Cardiff, Wales, CF10 3AT, UK
| | - Michael A Birkett
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Éva Bálintné Csonka
- Plant Protection Institute, Centre for Agricultural Research, Eötvös Loránd Research Network (ELKH), H-1022 Herman Ottó u. 15, Budapest, Hungary
| | - Miklós Tóth
- Plant Protection Institute, Centre for Agricultural Research, Eötvös Loránd Research Network (ELKH), H-1022 Herman Ottó u. 15, Budapest, Hungary
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13
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Di Ilio V, Birkett MA, Pickett JA. Effects of Nicotine and Tobacco-Related Products on the Feeding Behavior of the German Cockroach (Blattodea: Blattellidae). J Insect Sci 2021; 21:3. [PMID: 33686433 PMCID: PMC7940502 DOI: 10.1093/jisesa/ieaa147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Indexed: 06/12/2023]
Abstract
Animals use olfaction to detect developmentally significant volatile organic compounds (VOCs) in their local environment. As part of a wider study aiming to demonstrate that the olfactory responses of animals to VOCs can be modified through the creation of a drug-addicted status and association with a selected VOC, we investigated nicotine and tobacco smoke particulate (TSP) extract as possible addictive compounds for male German cockroaches, Blattella germanica (Linnaeus). In feeding experiments using an artificial food stimulus, food treated with TSP extract was preferred over untreated food. Surprisingly, nicotine, which was expected to be the most important addictive tobacco component, did not induce noticeable effects on cockroach behavior. Both TSP extract and nicotine were shown to be phagostimulants. Olfactometry assays that measured odor-mediated insect behavior demonstrated that male B. germanica did not choose TSP-extract-treated food even when attempts were made specifically to train them via this modality. These results support a hypothesis that B. germanica needs to consume TSP-containing food to show a clear preference for this stimulus and that gustatory mechanisms are involved due to compounds present in the TSP extract.
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Affiliation(s)
- Vincenzo Di Ilio
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, UK
- BBCA Onlus, Rome, Italy
| | - Michael A Birkett
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, UK
| | - John A Pickett
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire, UK
- School of Chemistry, Cardiff University, Cardiff, Wales, UK
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14
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Li W, Wang L, Zhou F, Li C, Ma W, Chen H, Wang G, Pickett JA, Zhou JJ, Lin Y. Overexpression of the homoterpene synthase gene, OsCYP92C21, increases emissions of volatiles mediating tritrophic interactions in rice. Plant Cell Environ 2021; 44:948-963. [PMID: 33099790 DOI: 10.1111/pce.13924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/12/2020] [Accepted: 10/19/2020] [Indexed: 06/11/2023]
Abstract
Plant defence homoterpenes can be used to attract pest natural enemies. However, the biosynthetic pathway of homoterpenes is still unknown in rice, and the practical application of such indirect defence systems suffers from inherent limitations due to their low emissions from plants. Here, we demonstrated that the protein OsCYP92C21 is responsible for homoterpene biosynthesis in rice. We also revealed that the ability of rice to produce homoterpenes is dependent on the subcellular precursor pools. By increasing the precursor pools through specifically subcellular targeting expression, genetic transformation and genetic introgression, we significantly enhanced homoterpene biosynthesis in rice. The final introgressed GM rice plants exhibited higher homoterpene emissions than the wild type rice and the highest homoterpene emission reported so far for such GM plants even without the induction of herbivore attack. As a result, these GM rice plants demonstrated strong attractiveness to the parasitic wasp Cotesia chilonis. This study discovered the homoterpene biosynthesis pathway in rice, and lays the foundation for the utilisation of plant indirect defence mechanism in the "push-pull" strategy of integrated pest management through increasing precursor pools in the subcellular compartments and overexpressing homoterpene synthase by genetic transformation.
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Affiliation(s)
- Wei Li
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, Huazhong Agricultural University, Wuhan, China
| | - Lingnan Wang
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, Huazhong Agricultural University, Wuhan, China
| | - Fei Zhou
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, Huazhong Agricultural University, Wuhan, China
| | - Changyan Li
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, Huazhong Agricultural University, Wuhan, China
| | - Weihua Ma
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Hao Chen
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, Huazhong Agricultural University, Wuhan, China
| | - Guirong Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | | | - Jing-Jiang Zhou
- Biocontrol Engineering Laboratory of Crop Diseases and Pests of Gansu Province, Gansu Agricultural University, Lanzhou, China
- College of Plant Protection, Gansu Agricultural University, Lanzhou, China
| | - Yongjun Lin
- National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, Huazhong Agricultural University, Wuhan, China
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15
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Tamiru A, Paliwal R, Manthi SJ, Odeny DA, Midega CAO, Khan ZR, Pickett JA, Bruce TJA. Genome wide association analysis of a stemborer egg induced "call-for-help" defence trait in maize. Sci Rep 2020; 10:11205. [PMID: 32641801 PMCID: PMC7343780 DOI: 10.1038/s41598-020-68075-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 06/15/2020] [Indexed: 11/30/2022] Open
Abstract
Tritrophic interactions allow plants to recruit natural enemies for protection against herbivory. Here we investigated genetic variability in induced responses to stemborer egg-laying in maize Zea mays (L.) (Poaceae). We conducted a genome wide association study (GWAS) of 146 maize genotypes comprising of landraces, inbred lines and commercial hybrids. Plants were phenotyped in bioassays measuring parasitic wasp Cotesia sesamiae (Cameron) (Hymenoptera: Braconidae) attraction to volatiles collected from plants exposed to stemborer Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) eggs. Genotyping-by-sequencing was used to generate maize germplasm SNP data for GWAS. The egg-induced parasitoid attraction trait was more common in landraces than in improved inbred lines and hybrids. GWAS identified 101 marker-trait associations (MTAs), some of which were adjacent to genes involved in the JA-defence pathway (opr7, aos1, 2, 3), terpene biosynthesis (fps3, tps2, 3, 4, 5, 7, 9, 10), benzoxazinone synthesis (bx7, 9) and known resistance genes (e.g. maize insect resistance 1, mir1). Intriguingly, there was also association with a transmembrane protein kinase that may function as a receptor for the egg elicitor and other genes implicated in early plant defence signalling. We report maize genomic regions associated with indirect defence and provide a valuable resource for future studies of tritrophic interactions in maize. The markers identified may facilitate selection of indirect defence by maize breeders.
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Affiliation(s)
- Amanuel Tamiru
- International Centre of Insect Physiology and Ecology (ICIPE), P.O. Box 30772-00100, Nairobi, Kenya
| | - Rajneesh Paliwal
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), P.O. Box 39063-00623, Nairobi, Kenya.,International Institute of Tropical Agriculture (IITA), 5320, Ibadan, Nigeria
| | - Samuel J Manthi
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), P.O. Box 39063-00623, Nairobi, Kenya
| | - Damaris A Odeny
- International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), P.O. Box 39063-00623, Nairobi, Kenya
| | - Charles A O Midega
- International Centre of Insect Physiology and Ecology (ICIPE), P.O. Box 30772-00100, Nairobi, Kenya
| | - Zeyaur R Khan
- International Centre of Insect Physiology and Ecology (ICIPE), P.O. Box 30772-00100, Nairobi, Kenya
| | - John A Pickett
- School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK
| | - Toby J A Bruce
- School of Life Sciences, Keele University, Staffordshire, ST5 5BG, UK.
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16
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Radadiya A, Pickett JA. Characterizing human odorant signals: insights from insect semiochemistry and in silico modelling. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190263. [PMID: 32306882 DOI: 10.1098/rstb.2019.0263] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Interactions relating to human chemical signalling, although widely acknowledged, are relatively poorly characterized chemically, except for human axillary odour. However, the extensive chemical ecology of insects, involving countless pheromone and other semiochemical identifications, may offer insights into overcoming problems of characterizing human-derived semiochemicals more widely. Current techniques for acquiring insect semiochemicals are discussed, particularly in relation to the need for samples to relate, as closely as possible, to the ecological situation in which they are naturally deployed. Analysis is facilitated by chromatography coupled to electrophysiological preparations from the olfactory organs of insects in vivo. This is not feasible with human olfaction, but there are now potential approaches using molecular genetically reconstructed olfactory preparations already in use with insect systems. There are specific insights of value for characterizing human semiochemicals from advanced studies on semiochemicals of haematophagous insects, which include those involving human hosts, in addition to wider studies on farm and companion animals. The characterization of the precise molecular properties recognized in olfaction could lead to new advances in analogue design and a range of novel semiochemicals for human benefit. There are insights from successful synthetic biology studies on insect semiochemicals using novel biosynthetic precursors. Already, wider opportunities in olfaction emerging from in silico studies, involving a range of theoretical and computational approaches to molecular design and understanding olfactory systems at the molecular level, are showing promise for studying human semiochemistry. This article is part of the Theo Murphy meeting issue 'Olfactory communication in humans'.
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Affiliation(s)
- Ashish Radadiya
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, UK
| | - John A Pickett
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, UK
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17
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Weeks ENI, Logan JG, Birkett MA, Caulfield JC, Gezan SA, Welham SJ, Brugman VA, Pickett JA, Cameron MM. Electrophysiologically and behaviourally active semiochemicals identified from bed bug refuge substrate. Sci Rep 2020; 10:4590. [PMID: 32165700 PMCID: PMC7067832 DOI: 10.1038/s41598-020-61368-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 02/21/2020] [Indexed: 11/09/2022] Open
Abstract
Bed bugs are pests of public health importance due to their relentless biting habits that can lead to allergies, secondary infections and mental health issues. When not feeding on human blood bed bugs aggregate in refuges close to human hosts. This aggregation behaviour could be exploited to lure bed bugs into traps for surveillance, treatment efficacy monitoring and mass trapping efforts, if the responsible cues are identified. The aim of this study was to identify and quantify the bed bug aggregation pheromone. Volatile chemicals were collected from bed bug-exposed papers, which are known to induce aggregation behaviour, by air entrainment. This extract was tested for behavioural and electrophysiological activity using a still-air olfactometer and electroantennography, respectively. Coupled gas chromatography-electroantennography (GC-EAG) was used to screen the extract and the GC-EAG-active chemicals, benzaldehyde, hexanal, (E)-2-octenal, octanal, nonanal, decanal, heptanal, (R,S)-1-octen-3-ol, 3-carene, β-phellandrene, (3E,5E)-octadien-2-one, (E)-2-nonenal, 2-decanone, dodecane, nonanoic acid, 2-(2-butoxyethoxy)ethyl acetate, (E)-2-undecanal and (S)-germacrene D, were identified by GC-mass spectrometry and quantified by GC. Synthetic blends, comprising 6, 16, and 18 compounds, at natural ratios, were then tested in the still-air olfactometer to determine behavioural activity. These aggregation chemicals can be manufactured into a lure that could be used to improve bed bug management.
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Affiliation(s)
- E N I Weeks
- Entomology and Nematology Department, University of Florida, 970 Natural Area Drive, Gainesville, Florida, 32611, USA.
| | - J G Logan
- Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.,Vecotech Ltd, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - M A Birkett
- Department of Biointeractions and Crop Protection, Rothamsted Research, West Common, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - J C Caulfield
- Department of Biointeractions and Crop Protection, Rothamsted Research, West Common, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - S A Gezan
- VSN International Ltd, 2 Amberside House, Hemel Hempstead, HP2 4TP, UK
| | - S J Welham
- Stats4biol Consultancy, 31 Longcroft Lane, Welwyn Garden City, AL8 6EB, UK
| | - V A Brugman
- Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.,Vecotech Ltd, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - J A Pickett
- School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK
| | - M M Cameron
- Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.,Vecotech Ltd, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
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18
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Robinson A, Bristow J, Holl MV, Makalo P, Alemayehu W, Bailey RL, Macleod D, Birkett MA, Caulfield JC, Sarah V, Pickett JA, Dewhirst S, Chen-Hussey V, Woodcock CM, D’Alessandro U, Last A, Burton MJ, Lindsay SW, Logan JG. Responses of the putative trachoma vector, Musca sorbens, to volatile semiochemicals from human faeces. PLoS Negl Trop Dis 2020; 14:e0007719. [PMID: 32126087 PMCID: PMC7069642 DOI: 10.1371/journal.pntd.0007719] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 03/13/2020] [Accepted: 01/13/2020] [Indexed: 12/12/2022] Open
Abstract
The putative vector of trachoma, Musca sorbens, prefers to lay its eggs on human faeces on the ground. This study sought to determine whether M. sorbens females were attracted to volatile odours from human faeces in preference to odours from the faeces of other animals, and to determine whether specific volatile semiochemicals mediate selection of the faeces. Traps baited with the faeces of humans and local domestic animals were used to catch flies at two trachoma-endemic locations in The Gambia and one in Ethiopia. At all locations, traps baited with faeces caught more female M. sorbens than control traps baited with soil, and human faeces was the most successful bait compared with soil (mean rate ratios 44.40, 61.40, 10.50 [P<0.001]; 8.17 for child faeces [P = 0.004]). Odours from human faeces were sampled by air entrainment, then extracts of the volatiles were tested by coupled gas chromatography-electroantennography with laboratory-reared female M. sorbens. Twelve compounds were electrophysiologically active and tentatively identified by coupled mass spectrometry-gas chromatography, these included cresol, indole, 2-methylpropanoic acid, butanoic acid, pentanoic acid and hexanoic acid. It is possible that some of these volatiles govern the strong attraction of M. sorbens flies to human faeces. If so, a synthetic blend of these chemicals, at the correct ratios, may prove to be a highly attractive lure. This could be used in odour-baited traps for monitoring or control of this species in trachoma-endemic regions.
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Affiliation(s)
- Ailie Robinson
- Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
| | - Julie Bristow
- Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
- Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Matthew V. Holl
- Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
| | - Pateh Makalo
- Medical Research Council Unit, The Gambia, The Gambia
| | | | - Robin L. Bailey
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - David Macleod
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Michael A. Birkett
- Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - John C. Caulfield
- Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Virginia Sarah
- Global Partnerships Executive, The Fred Hollows Foundation, Crawford Mews, London, United Kingdom
| | - John A. Pickett
- Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Sarah Dewhirst
- ARCTEC, Chariot Innovations Ltd, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Vanessa Chen-Hussey
- ARCTEC, Chariot Innovations Ltd, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Christine M. Woodcock
- Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | | | - Anna Last
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Matthew J. Burton
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Steve W. Lindsay
- Department of Biosciences, Durham University, Durham, County Durham, United Kingdom
| | - James G. Logan
- Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
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19
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Wamonje FO, Donnelly R, Tungadi TD, Murphy AM, Pate AE, Woodcock C, Caulfield J, Mutuku JM, Bruce TJA, Gilligan CA, Pickett JA, Carr JP. Different Plant Viruses Induce Changes in Feeding Behavior of Specialist and Generalist Aphids on Common Bean That Are Likely to Enhance Virus Transmission. Front Plant Sci 2020; 10:1811. [PMID: 32082355 PMCID: PMC7005137 DOI: 10.3389/fpls.2019.01811] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 12/27/2019] [Indexed: 05/23/2023]
Abstract
Bean common mosaic virus (BCMV), bean common mosaic necrosis virus (BCMNV), and cucumber mosaic virus (CMV) cause serious epidemics in common bean (Phaseolus vulgaris), a vital food security crop in many low-to-medium income countries, particularly in Sub-Saharan Africa. Aphids transmit these viruses "non-persistently," i.e., virions attach loosely to the insects' stylets. Viruses may manipulate aphid-host interactions to enhance transmission. We used direct observation and electrical penetration graph measurements to see if the three viruses induced similar or distinct changes in feeding behaviors of two aphid species, Aphis fabae and Myzus persicae. Both aphids vector BCMV, BCMNV, and CMV but A. fabae is a legume specialist (the dominant species in bean fields) while M. persicae is a generalist that feeds on and transmits viruses to diverse plant hosts. Aphids of both species commenced probing epidermal cells (behavior optimal for virus acquisition and inoculation) sooner on virus-infected plants than on mock-inoculated plants. Infection with CMV was especially disruptive of phloem feeding by the bean specialist aphid A. fabae. A. fabae also experienced mechanical stylet difficulty when feeding on virus-infected plants, and this was also exacerbated for M. persicae. Overall, feeding on virus-infected host plants by specialist and generalist aphids was affected in different ways but all three viruses induced similar effects on each aphid type. Specifically, non-specialist (M. persicae) aphids encountered increased stylet difficulties on plants infected with BCMV, BCMNV, or CMV, whereas specialist aphids (A. fabae) showed decreased phloem ingestion on infected plants. Probing and stylet pathway activity (which facilitate virus transmission) were not decreased by any of the viruses for either of the aphid species, except in the case of A. fabae on CMV-infected bean, where these activities were increased. Overall, these virus-induced changes in host-aphid interactions are likely to enhance non-persistent virus transmission, and data from this work will be useful in epidemiological modeling of non-persistent vectoring of viruses by aphids.
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Affiliation(s)
- Francis O. Wamonje
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Ruairí Donnelly
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Trisna D. Tungadi
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Alex M. Murphy
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Adrienne E. Pate
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Christine Woodcock
- Biointeractions and Crop Protection, Rothamsted Research, Harpenden, United Kingdom
| | - John Caulfield
- Biointeractions and Crop Protection, Rothamsted Research, Harpenden, United Kingdom
| | - J. Musembi Mutuku
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
- Biosciences Eastern and Central Africa, International Livestock Research Institute, Nairobi, Kenya
| | - Toby J. A. Bruce
- Biointeractions and Crop Protection, Rothamsted Research, Harpenden, United Kingdom
| | | | - John A. Pickett
- Biointeractions and Crop Protection, Rothamsted Research, Harpenden, United Kingdom
| | - John P. Carr
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
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Sobhy IS, Caulfield JC, Pickett JA, Birkett MA. Sensing the Danger Signals: cis-Jasmone Reduces Aphid Performance on Potato and Modulates the Magnitude of Released Volatiles. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2019.00499] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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Wamonje FO, Tungadi TD, Murphy AM, Pate AE, Woodcock C, Caulfield JC, Mutuku JM, Cunniffe NJ, Bruce TJA, Gilligan CA, Pickett JA, Carr JP. Three Aphid-Transmitted Viruses Encourage Vector Migration From Infected Common Bean ( Phaseolus vulgaris) Plants Through a Combination of Volatile and Surface Cues. Front Plant Sci 2020; 11:613772. [PMID: 33381144 PMCID: PMC7767818 DOI: 10.3389/fpls.2020.613772] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 11/19/2020] [Indexed: 05/14/2023]
Abstract
Bean common mosaic virus (BCMV), bean common mosaic necrosis virus (BCMNV), and cucumber mosaic virus (CMV) are important pathogens of common bean (Phaseolus vulgaris), a crop vital for food security in sub-Saharan Africa. These viruses are vectored by aphids non-persistently, with virions bound loosely to stylet receptors. These viruses also manipulate aphid-mediated transmission by altering host properties. Virus-induced effects on host-aphid interactions were investigated using choice test (migration) assays, olfactometry, and analysis of insect-perceivable volatile organic compounds (VOCs) using gas chromatography (GC)-coupled mass spectrometry, and GC-coupled electroantennography. When allowed to choose freely between infected and uninfected plants, aphids of the legume specialist species Aphis fabae, and of the generalist species Myzus persicae, were repelled by plants infected with BCMV, BCMNV, or CMV. However, in olfactometer experiments with A. fabae, only the VOCs emitted by BCMNV-infected plants repelled aphids. Although BCMV, BCMNV, and CMV each induced distinctive changes in emission of aphid-perceivable volatiles, all three suppressed emission of an attractant sesquiterpene, α-copaene, suggesting these three different viruses promote migration of virus-bearing aphids in a similar fashion.
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Affiliation(s)
- Francis O. Wamonje
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Trisna D. Tungadi
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Alex M. Murphy
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Adrienne E. Pate
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | | | | | - J. Musembi Mutuku
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
- Biosciences Eastern and Central Africa, International Livestock Research Institute, Nairobi, Kenya
| | - Nik J. Cunniffe
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | | | | | | | - John P. Carr
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
- *Correspondence: John P. Carr, ;
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Tolosa TA, Tamiru A, Midega CAO, Van Den Berg J, Birkett MA, Woodcock CM, Bruce TJA, Kelemu S, Pickett JA, Khan ZR. Molasses Grass Induces Direct and Indirect Defense Responses in Neighbouring Maize Plants. J Chem Ecol 2019; 45:982-992. [PMID: 31784860 DOI: 10.1007/s10886-019-01122-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 09/20/2019] [Accepted: 10/28/2019] [Indexed: 01/02/2023]
Abstract
Plants have evolved intricate defence strategies against herbivore attack which can include activation of defence in response to stress-related volatile organic compounds (VOCs) emitted by neighbouring plants. VOCs released by intact molasses grass (Melinis minutiflora), have been shown to repel stemborer, Chilo partellus (Swinhoe), from maize and enhance parasitism by Cotesia sesamiae (Cameron). In this study, we tested whether the molasses grass VOCs have a role in plant-plant communication by exposing different maize cultivars to molasses grass for a 3-week induction period and then observing insect responses to the exposed plants. In bioassays, C. partellus preferred non-exposed maize landrace plants for egg deposition to those exposed to molasses grass. Conversely, C. sesamiae parasitoid wasps preferred volatiles from molasses grass exposed maize landraces compared to volatiles from unexposed control plants. Interestingly, the molasses grass induced defence responses were not observed on hybrid maize varieties tested, suggesting that the effect was not simply due to absorption and re-emission of VOCs. Chemical and electrophysiological analyses revealed strong induction of bioactive compounds such as (R)-linalool, (E)-4,8-dimethyl-1,3,7-nonatriene and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene from maize landraces exposed to molasses grass volatiles. Our results suggest that constitutively emitted molasses grass VOCs can induce direct and indirect defence responses in neighbouring maize landraces. Plants activating defences by VOC exposure alone could realize enhanced levels of resistance and fitness compared to those that launch defence responses upon herbivore attack. Opportunities for exploiting plant-plant signalling to develop ecologically sustainable crop protection strategies against devastating insect pests such as stemborer C. partellus are discussed.
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Affiliation(s)
- Tigist A Tolosa
- International Centre of Insect Physiology and Ecology, P.O. Box 30772-00100, Nairobi, Kenya
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2520, South Africa
- Department of Agriculture Food and Resource Sciences, University of Maryland Eastern Shore, Princess Anne, MD, 21853, USA
| | - Amanuel Tamiru
- International Centre of Insect Physiology and Ecology, P.O. Box 30772-00100, Nairobi, Kenya.
| | - Charles A O Midega
- International Centre of Insect Physiology and Ecology, P.O. Box 30772-00100, Nairobi, Kenya
| | - Johnnie Van Den Berg
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2520, South Africa
| | - Michael A Birkett
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Herts, AL5 2JQ, UK
| | - Christine M Woodcock
- Biointeractions and Crop Protection Department, Rothamsted Research, Harpenden, Herts, AL5 2JQ, UK
| | - Toby J A Bruce
- School of Life Sciences, Keele University, Staffordshire, ST5 5BG, UK
| | - Segenet Kelemu
- International Centre of Insect Physiology and Ecology, P.O. Box 30772-00100, Nairobi, Kenya
| | - John A Pickett
- School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK
| | - Zeyaur R Khan
- International Centre of Insect Physiology and Ecology, P.O. Box 30772-00100, Nairobi, Kenya
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2520, South Africa
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Pickett JA, Midega CAO, Pittchar J, Khan ZR. Removing constraints to sustainable food production: new ways to exploit secondary metabolism from companion planting and GM. Pest Manag Sci 2019; 75:2346-2352. [PMID: 31166075 PMCID: PMC6771526 DOI: 10.1002/ps.5508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 05/20/2019] [Accepted: 05/31/2019] [Indexed: 06/09/2023]
Abstract
The entire process of agricultural and horticultural food production is unsustainable as practiced by current highly intensive industrial systems. Energy consumption is particularly intensive for cultivation, and for fertilizer production and its incorporation into soil. Provision of nitrogen contributes a major source of the greenhouse gas, N2 O. All losses due to pests, diseases and weeds are of food for which the carbon footprint has already been committed and so crop protection becomes an even greater concern. The rapidly increasing global need for food and the aggravation of associated problems by the effects of climate change create a need for new and sustainable crop protection. The overall requirement for sustainability is to remove seasonal inputs, and consequently all crop protection will need to be delivered via the seed or other planting material. Although genetic modification (GM) has transformed the prospects of sustainable crop protection, considerably more development is essential for the realisation of the full potential of GM and thereby consumer acceptability. Secondary plant metabolism offers wider and perhaps more robust new crop protection via GM and can be accomplished without associated yield loss because of the low level of photosynthate diverted for plant defence by secondary metabolism. Toxic mechanisms can continue to be targeted but exploiting non-toxic regulatory and signalling mechanisms should be the ultimate objective. There are many problems facing these proposals, both technical and social, and these are discussed but it is certainly not possible to stay where we are in terms of sustainability. The evidence for success is mounting and the technical opportunities from secondary plant metabolism are discussed here. © 2019 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- John A Pickett
- School of ChemistryUniversity of CardiffCardiffUnited Kingdom
| | - Charles AO Midega
- Push‐pull IPM Technology, Plant Health, International Centre of Insect Physiology and EcologyNairobiKenya
| | - Jimmy Pittchar
- Push‐pull IPM Technology, Plant Health, International Centre of Insect Physiology and EcologyNairobiKenya
| | - Zeyaur R Khan
- Push‐pull IPM Technology, Plant Health, International Centre of Insect Physiology and EcologyNairobiKenya
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Hassemer MJ, Borges M, Withall DM, Pickett JA, Laumann RA, Birkett MA, Blassioli-Moraes MC. Development of pull and push-pull systems for management of lesser mealworm, Alphitobius diaperinus, in poultry houses using alarm and aggregation pheromones. Pest Manag Sci 2019; 75:1107-1114. [PMID: 30270497 DOI: 10.1002/ps.5225] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 09/24/2018] [Accepted: 09/24/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND The lesser mealworm, Alphitobius diaperinus (Coleoptera: Tenebrionidae), is the most important insect pest affecting poultry production around the world, with all life stages being susceptible to infection by bacteria, viruses and fungi. Control of A. diaperinus in poultry houses using intensive insecticide application is not effective due to the cryptic behaviour of this pest. Here, we evaluated the potential of recently identified A. diaperinus alarm (1,4-benzoquinone, 2-methyl-1,4-benzoquinone and 2-ethyl-1,4-benzoquinone) and aggregation [(R)-limonene, 2-nonanone, (E)-ocimene, (S)-linalool, (R)-daucene and (E,E)-α-farnesene] pheromones as tools for the management of this pest in poultry houses in Brazil. RESULTS Laboratory arena assays with synthetic alarm pheromone confirmed A. diaperinus repellency. In an initial field assay, traps baited with synthetic aggregation pheromone captured significantly more insects than control traps. In further field assays that compared a pull (aggregation pheromone) and a push-pull (simultaneous alarm/aggregation pheromone deployment) system, a higher number of A. diaperinus were captured in aggregation pheromone-baited traps in the push-pull system. CONCLUSION Our results suggest that alarm and aggregation pheromones can be deployed in poultry houses to trap significant numbers of adult A. diaperinus. Studies are underway to determine the potential for using these components as part of an integrated A. diaperinus management strategy. © 2018 Society of Chemical Industry.
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Affiliation(s)
- Marla J Hassemer
- Department of Zoology, Institute of Biological Sciences, University of Brasília, Brasília, Brazil
- Semiochemicals Laboratory, Embrapa Genetics Resources and Biotechnology, Embrapa Genetics Resources and Biotechnology, Brasília, Brazil
| | - Miguel Borges
- Semiochemicals Laboratory, Embrapa Genetics Resources and Biotechnology, Embrapa Genetics Resources and Biotechnology, Brasília, Brazil
| | | | - John A Pickett
- School of Chemistry, Cardif University, Cardif CF10 3AT, UK
| | - Raul A Laumann
- Semiochemicals Laboratory, Embrapa Genetics Resources and Biotechnology, Embrapa Genetics Resources and Biotechnology, Brasília, Brazil
| | | | - Maria C Blassioli-Moraes
- Semiochemicals Laboratory, Embrapa Genetics Resources and Biotechnology, Embrapa Genetics Resources and Biotechnology, Brasília, Brazil
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Ferreira LL, Sarria ALF, de Oliveira Filho JG, de Silva FDO, Powers SJ, Caulfield JC, Pickett JA, Birkett MA, Borges LMF. Identification of a non-host semiochemical from tick-resistant donkeys (Equus asinus) against Amblyomma sculptum ticks. Ticks Tick Borne Dis 2019; 10:621-627. [PMID: 30799282 PMCID: PMC6446183 DOI: 10.1016/j.ttbdis.2019.02.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Revised: 01/28/2019] [Accepted: 02/10/2019] [Indexed: 11/09/2022]
Abstract
Amblyomma sculptum is a tick affecting animal and human health across Argentina, Bolivia, Paraguay and Brazil. Donkeys, Equus asinus, are known to be resistant to A. sculptum, suggesting that they can produce non-host tick semiochemicals (allomones), as already demonstrated for some other vertebrate host/pest interactions, whereas horses, Equus caballus, are considered as susceptible hosts. In this study, we tested the hypothesis that donkeys produce natural repellents against A. sculptum, by collecting sebum from donkeys and horses, collecting the odour from sebum extracts, and identifying donkey-specific volatile compounds by gas chromatography (GC) and coupled GC-mass spectrometry (GC–MS). From the complex collected blends, five main compounds were identified in both species. Hexanal, heptanal and (E)-2-decenal were found predominantly in donkey extracts, whilst ethyl octanoate and ethyl decanoate were found predominantly in horse extracts. One compound, (E)-2-octenal, was detected exclusively in donkey extracts. In Y-tube olfactometer bioassays 36 different A. sculptum nymphs were tested for each extract, compound and concentration. The dry sebum extracts and the compounds identified in both species induced neither attraction nor repellency. Only (E)-2-octenal, the donkey-specific compound, displayed repellency, with more nymphs preferring the arm containing the solvent control when the compound was presented in the test arm across four concentrations tested (p < 0.05, Chi-square test). A combination of a tick attractant (ammonia) and (E)-2-octenal at 0.25 M also resulted in preference for the control arm (p < 0.05, Chi-square test). The use of semiochemicals (allomones) identified from less-preferred hosts in tick management has been successful for repelling brown dog ticks, Rhipicephalus sanguineus sensu lato from dog hosts. These results indicate that (E)-2-octenal could be used similarly to interfere in tick host location and be developed for use in reducing A. sculptum numbers on animal and human hosts.
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Affiliation(s)
- Lorena Lopes Ferreira
- Escola de Veterinária e Zootecnia, Universidade Federal de Goiás, Campus Samambaia, Avenida Esperança, s/n, Campus Universitário, CEP: 74690-900, Goiânia, Goiás, Brazil.
| | | | - Jaires Gomes de Oliveira Filho
- Escola de Veterinária e Zootecnia, Universidade Federal de Goiás, Campus Samambaia, Avenida Esperança, s/n, Campus Universitário, CEP: 74690-900, Goiânia, Goiás, Brazil.
| | - Fernanda de Oliveira de Silva
- Escola de Veterinária e Zootecnia, Universidade Federal de Goiás, Campus Samambaia, Avenida Esperança, s/n, Campus Universitário, CEP: 74690-900, Goiânia, Goiás, Brazil.
| | - Stephen J Powers
- Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, United Kingdom.
| | - John C Caulfield
- Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, United Kingdom.
| | - John A Pickett
- Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, United Kingdom.
| | - Michael A Birkett
- Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, United Kingdom.
| | - Lígia Miranda Ferreira Borges
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Rua 235 s/n, Setor Universitário, CEP: 74605050, Goiânia, Goiás, Brazil.
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Abagale SA, Woodcock CM, Chamberlain K, Osafo‐Acquaah S, van Emden H, Birkett MA, Pickett JA, Braimah H. Attractiveness of host banana leaf materials to the banana weevil, Cosmopolites sordidus in Ghana for development of field management strategies. Pest Manag Sci 2019; 75:549-555. [PMID: 30136428 PMCID: PMC6492155 DOI: 10.1002/ps.5182] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 08/20/2018] [Accepted: 08/20/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND The banana weevil, Cosmopolites sordidus, has been frequently cited as the most challenging constraint to banana and plantain production, particularly in small-scale (smallholder) farming. For the development of a new, low-cost weevil management technology based on attractive host plant material, we previously identified (2R,5S)-theaspirane as the active component of attractive senesced banana leaves. In this new study, we used behavioural (olfactometer) bioassays with adult weevils to compare the attractiveness of four different developmental stages of banana leaves, i.e. unfolding (pale green), matured green (deep green), matured yellowing and senesced, to determine which leaf developmental stage would be most appropriate for use in weevil management. We also investigated the attractiveness of senesced leaf extracts prepared using different solvents to determine which solvent would be most appropriate for local production of leaf extracts. Coupled gas chromatography-electroantennography (GC-EAG) was then used with adult weevils to confirm the presence of (2R,5S)-theaspirane in attractive leaf extracts. RESULTS Of the leaf materials tested, only the odour of senesced leaf material was significantly attractive to adult weevils (P < 0.005). Furthermore, an extract of senesced material prepared using palm wine alcohol was significantly attractive (P < 0.05). Using coupled GC-EAG with weevil antennae, (2R,5S)-theaspirane was identified as a minor component with strong EAG activity within the palm wine alcohol extract. CONCLUSION The results suggest that palm wine alcohol extracts of senesced banana leaf material could be used to lure adult C. sordidus to traps in the field, as part of an ethnobotanical-based approach for C. sordidus management on smallholder farms. © 2018 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Samson A Abagale
- Crops Research Institute, Council for Scientific and Industrial ResearchKumasiGhana
- Department of ChemistryKwame Nkrumah University of Science and TechnologyKumasiGhana
| | | | - Keith Chamberlain
- Biointeractions and Crop Protection DepartmentRothamsted ResearchHarpendenUK
| | - Samuel Osafo‐Acquaah
- Department of ChemistryKwame Nkrumah University of Science and TechnologyKumasiGhana
| | - Helmut van Emden
- School of Agriculture, Policy and DevelopmentThe University of ReadingReadingUK
| | - Michael A Birkett
- Biointeractions and Crop Protection DepartmentRothamsted ResearchHarpendenUK
| | | | - Haruna Braimah
- Crops Research Institute, Council for Scientific and Industrial ResearchKumasiGhana
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Vuts J, Woodcock CM, König L, Powers SJ, Pickett JA, Szentesi Á, Birkett MA. Host shift induces changes in mate choice of the seed predator Acanthoscelides obtectus via altered chemical signalling. PLoS One 2018; 13:e0206144. [PMID: 30427867 PMCID: PMC6235263 DOI: 10.1371/journal.pone.0206144] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Accepted: 10/08/2018] [Indexed: 11/18/2022] Open
Abstract
The mechanisms of host shift in phytophagous insects are poorly understood. Among the many proposed processes involved, sexual selection via semiochemicals has recently been suggested. This hypothesizes that sexual communication using pheromones is modified as a result of development on a new host, and such plant-induced phenotypic divergence in mate recognition cues can lead to reproductive isolation between host lines. We tested this hypothesis on Acanthoscelides obtectus, an oligophagous bruchid of Phaseolus vulgaris beans worldwide, which also develops in acceptable non-hosts, such as chickpea (Cicer arietinum L.). Male sex pheromone blends of the bean, chickpea and chickpea/bean host lines during artificially induced host shifts showed different composition. Bean-reared females did not distinguish between blends, whereas chickpea and chickpea/bean females preferred the chickpea male pheromone. However, electrophysiological (EAG) responses to male odour of antennae of the three female host lines were similar, all preferring bean-reared males. Egg-laying choice tests revealed a uniform preference for bean seeds across female host lines, even after multiple generations, whereas larvae did not distinguish between bean and chickpea seeds. We conclude that the development of divergent chemical signalling systems during host shifts does not facilitate the evolution of host races in A. obtectus, because oviposition preferences remain unaffected.
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Affiliation(s)
- József Vuts
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, United Kingdom
- * E-mail:
| | - Christine M. Woodcock
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, United Kingdom
| | | | - Stephen J. Powers
- Department of Computational and Analytical Sciences, Rothamsted Research, Harpenden, United Kingdom
| | - John A. Pickett
- School of Chemistry, Cardiff University, Cardiff, United Kingdom
| | - Árpád Szentesi
- Department of Systematic Zoology and Ecology, Eötvös Loránd University, Budapest, Hungary
| | - Michael A. Birkett
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, United Kingdom
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Schlaeger S, Pickett JA, Birkett MA. Prospects for management of whitefly using plant semiochemicals, compared with related pests. Pest Manag Sci 2018; 74:2405-2411. [PMID: 29717814 PMCID: PMC6221090 DOI: 10.1002/ps.5058] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 04/27/2018] [Accepted: 04/27/2018] [Indexed: 06/08/2023]
Abstract
Whitefly (Hemiptera: Sternorrhyncha: Aleyrodidae) pests, including the tobacco whitefly, Bemisia tabaci, and the greenhouse whitefly, Trialeurodes vaporariorum, are important economically in agriculture. Whiteflies are controlled mainly by synthetic insecticides but resistance to these is evolving rapidly. A semiochemical-based management strategy could provide an alternative to the use of insecticides, by exploiting natural volatile signalling processes to manipulate insect behaviour. Whitefly behaviour is affected by differences in plant odour blends. Selected compounds have been suggested as putative semiochemicals, but in only a few studies have potential volatiles been characterized by electrophysiology or olfactometry. Application of antennal preparation methods from closely related families, the aphids (Hemiptera: Aphididae) and psyllids (Hemiptera: Psyllidae), may help to facilitate whitefly electroantennography. Behavioural bioassays are essential to identify the repellent or attractant effect of each semiochemical. The relevance of semiochemicals in whitefly management needs to be evaluated in the respective cultivation system. Although the value of semiochemicals against whiteflies has not been demonstrated in the field, there is an emerging range of possible field applications and some promising prospects. Overall, the olfactory system of whiteflies needs to be elucidated in more detail. © 2018 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Stefanie Schlaeger
- Biointeractions and Crop Protection DepartmentRothamsted ResearchHarpendenUK
| | | | - Michael A Birkett
- Biointeractions and Crop Protection DepartmentRothamsted ResearchHarpendenUK
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Pickett JA, Weston LA. Possibilities for rationally exploiting co-evolution in addressing resistance to insecticides, and beyond. Pestic Biochem Physiol 2018; 151:18-24. [PMID: 30704708 DOI: 10.1016/j.pestbp.2018.03.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/09/2018] [Accepted: 03/20/2018] [Indexed: 06/09/2023]
Abstract
Certain biorational chemical agents used against insect pests impact essential stages or processes in insect life cycles when applied for pest management. Development of resistance to these agents, while involving maintenance of the natural role of the chemical agent, frequently requires the evolution of a new chemical structure by the resistant organism. When considering the process of resistance development, one could theoretically consider biorational structural determination rather than the less predictable or feasible generation of a novel replacement insecticide. At first consideration, this process might exclude toxicants such as typical pest control agents and rather be a phenomenon reserved principally for signalling processes such as are fulfilled by pheromones and other semiochemicals. However, because there is a unique co-evolutionary relationship between chemical defence and the physiology of the antagonistic organism, this process can be further explored for potential to overcome resistance to toxins. Given further consideration, newly evolved chemical defences may rationally provide options for new resistance-defeating chemistry. This review therefore discusses the potential for overcoming insecticide resistance through targeted application of this approach. Potential for use of a similar approach to counteract fungicide and herbicide resistance is also considered. Furthermore, the possible applications of this approach to address drug or pharmaceutic resistance are also considered.
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Affiliation(s)
- John A Pickett
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, United Kingdom.
| | - Leslie A Weston
- Graham Centre for Agricultural Innovation, Charles Sturt University, Wagga Wagga, NSW 2678, Australia.
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Abstract
Fall armyworm (FAW) Spodoptera frugiperda invaded Africa, with the first detections being reported in Central and Western Africa in early 2016, and now affects at least 40 countries in Africa, causing up to total crop loss amounting to over $6.2 billion p.a. FAW is an
invasive polyphagous pest that causes damage to economically important crops and has recently been reported in the Indian sub-continent. Effective control of FAW through use of synthetic chemical pesticides and genetically modified crops such as Bt maize faces challenges including improper
use, unaffordability by smallholder farmers and development of resistance by the pest. Additionally, dispersal of FAW larvae into the lower maize plant canopy keeps them out of reach of topical insecticide applications. Integrated pest management (IPM) packages like the push-pull technology
which eliminate pesticide use, and deploy natural processes are more suitable and cost-effective. Push-pull is a farming system intensification approach that involves attracting insect pests with trap plants (pull) such as Napier grass (Pennisetum purpureum) or Brachiaria grass, while
driving them away from the main crop using a repellent intercrop (push), Desmodium spp., commonly known as desmodium, and attracting natural parasitoids and predators to the field. In the rhizosphere, chemicals secreted by desmodium roots inhibit attachment of germinated striga to maize
or sorghum roots and abort germination of striga seeds which are rapidly depleted in the soil. Moreover, it improves soil fertility by fixing nitrogen, improving carbon sequestration, organic matter, moisture retention, and soil biota, and prevents further degradation of soil. The climate-adapted
push-pull technology significantly reduces plant damage by FAW and is the first IPM management tool for the pest in Africa, and is well suited to agro-ecosystem intensification needs of smallholder mixed farming systems in Africa and beyond. Both the African and the Asian continents provide
favourable climatic conditions for sustained reproduction of the FAW, which is expected to result in severe damage to crops; and being a new pest in both continents, it might have few natural enemies. Conventional control methods have limited effectiveness, as explained above. Therefore, an
IPM approach that is compatible with mixed cropping farming systems of small and medium scale farmers is necessary. The climate adapted push-pull is the first demonstrated IPM management tool for the FAW in Africa. The technology combines this with other concomitant benefits including control
of stemborers and the parasitic striga weeds, improvement of soil health through factors such as nitrogen fixation by desmodium, natural mulching, moisture retention and improvement of soil organic matter and soil biota. The combined benefits, including control of FAW, result in ecologically
sustainable higher crop yields, and well suited to agro-ecosystem intensification needs of smallholder mixed farming systems in Africa and beyond.
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Magalhães DM, Borges M, Laumann RA, Woodcock CM, Withall DM, Pickett JA, Birkett MA, Blassioli-Moraes MC. Identification of Volatile Compounds Involved in Host Location by Anthonomus grandis (Coleoptera: Curculionidae). Front Ecol Evol 2018. [DOI: 10.3389/fevo.2018.00098] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Abagale SA, Woodcock CM, Hooper AM, Caulfield JC, Withall D, Chamberlain K, Acquaah SO, Van Emden H, Braimah H, Pickett JA, Birkett MA. (2R,5S)-Theaspirane Identified as the Kairomone for the Banana Weevil, Cosmopolites sordidus, from Attractive Senesced Leaves of the Host Banana, Musa spp. Chemistry 2018; 24:9217-9219. [PMID: 29644772 PMCID: PMC6055713 DOI: 10.1002/chem.201800315] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Indexed: 11/06/2022]
Abstract
The principal active component produced by highly attractive senesced host banana leaves, Musa spp., for the banana weevil, Cosmopolites sordidus, is shown by coupled gas chromatography-electroantennography (GC-EAG), coupled GC-mass spectrometry (GC-MS), chemical synthesis and coupled enantioselective (chiral) GC-EAG to be (2R,5S)-theaspirane. In laboratory behaviour tests, the synthetic compound is as attractive as natural host leaf material and presents a new opportunity for pest control.
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Affiliation(s)
- Samson A Abagale
- Crops Research Institute, Council for Scientific and Industrial Research, P.O. Box 3785, Fumesua-Kumasi, Ghana.,Department of Chemistry, Kwame Nkrumah University of, Science and Technology, PMB, Kumasi, Ghana
| | - Christine M Woodcock
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Antony M Hooper
- School of Biological and Chemical Sciences, Queen Mary University of London, London, E1 4NS, UK
| | - John C Caulfield
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - David Withall
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Keith Chamberlain
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Samuel O Acquaah
- Department of Chemistry, Kwame Nkrumah University of, Science and Technology, PMB, Kumasi, Ghana
| | - Helmut Van Emden
- School of Agriculture, Policy and Development, The University of Reading, Earley Gate, P.O. Box 237, Reading, Berkshire, RG6 6AR, UK
| | - Haruna Braimah
- Crops Research Institute, Council for Scientific and Industrial Research, P.O. Box 3785, Fumesua-Kumasi, Ghana
| | - John A Pickett
- School of Chemistry, Cardiff University, Cardiff, Wales, CF10 3AT, UK
| | - Michael A Birkett
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
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Vuts J, Woodcock CM, Caulfield JC, Powers SJ, Pickett JA, Birkett MA. Isolation and identification of floral attractants from a nectar plant for the dried bean beetle, Acanthoscelides obtectus (Coleoptera: Chrysomelidae, Bruchinae). Pest Manag Sci 2018; 74:2069-2075. [PMID: 29516673 DOI: 10.1002/ps.4903] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 02/01/2018] [Accepted: 03/01/2018] [Indexed: 02/28/2024]
Abstract
BACKGROUND The response of virgin females of the legume pest Acanthoscelides obtectus (Coleoptera: Bruchidae) to headspace extracts of volatiles collected from flowers of a nectar plant, Daucus carota, was investigated using behaviour (four-arm olfactometry) and coupled gas chromatography-electroantennography (GC-EAG). RESULTS Odours from inflorescences were significantly more attractive to virgin female beetles than clean air. Similarly, a sample of volatile organic compounds (VOCs) collected by air entrainment (dynamic headspace collection) was more attractive to beetles than a solvent control. In coupled GC-EAG experiments with beetle antennae and the VOC extract, six components showed EAG activity. Using coupled GC-mass spectrometry (GC-MS) and GC peak enhancement with authentic standards, the components were identified as α-pinene (S:R 16:1), sabinene, myrcene, limonene (S:R 1:3), terpinolene and (S)-bornyl acetate. Females preferred the synthetic blend of D. carota EAG-active volatiles to the solvent control in bioassays. When compared directly, odours of D. carota inflorescences elicited stronger positive behaviour than the synthetic blend. CONCLUSION This is the first report of behaviourally active volatiles linked to pollen location for A. obtectus, and development of the six-component blend is being pursued, which could underpin the design of semiochemical-based field management approaches against this major pest of stored products. © 2018 Society of Chemical Industry.
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Fancelli M, Borges M, Laumann RA, Pickett JA, Birkett MA, Blassioli-Moraes MC. Attractiveness of Host Plant Volatile Extracts to the Asian Citrus Psyllid, Diaphorina citri, is Reduced by Terpenoids from the Non-Host Cashew. J Chem Ecol 2018; 44:397-405. [PMID: 29500752 PMCID: PMC5899996 DOI: 10.1007/s10886-018-0937-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 02/01/2018] [Accepted: 02/16/2018] [Indexed: 11/26/2022]
Abstract
Diaphorina citri is a vector of the bacterial causative agent of Huanglongbing (HLB = Citrus greening), a severe disease affecting citrus crops. As there is no known control for HLB, manipulating insect behaviour through deployment of semiochemicals offers a promising opportunity for protecting citrus crops. The behavioural responses of D. citri to plant volatiles, and the identity of these plant volatiles were investigated. Volatiles were collected from host plants Murraya paniculata, Citrus sinensis, C. reshni, C. limettioides, Poncirus trifoliata, and from non-host plants Psidium guajava, Mangifera indica, Anacardium occidentale. In behavioural assays, female D. citri spent more time in the arms containing volatiles from either M. paniculata or C. sinensis compared to the control arms. When D. citri was exposed to volatiles collected from A. occidentale, they preferred the control arm. Volatiles emitted from the other studied plants did not influence the foraging behaviour of D. citri. Chemical analyses of volatile extracts from C. sinensis, M. paniculata, and A. occidentale revealed the presence of the terpenoids (E)-4,8-dimethylnona-1,3,7–triene (DMNT) and (E,E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene (TMTT) in higher amounts in A. occidentale. In further behavioural bioassays, female D. citri spent less time in arms containing a synthetic blend of DMNT and TMTT compared to the control arms. Female D. citri also spent less time in arms containing the synthetic blend in combination with volatile extracts from either M. paniculata or C. sinensis compared to the control arms. Results suggest that higher release of the two terpenoids by A. occidentale make this species unattractive to D. citri, and that the terpenoids could be used in reducing colonisation of citrus plants and therefore HLB infection.
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Affiliation(s)
- Marilene Fancelli
- Embrapa Cassava and Fruits, PO Box 007, Cruz das Almas, 44380-000, Brazil.
| | - Miguel Borges
- Embrapa Genetic Resources and Biotechnology, Brasília, 70770-917, Brazil
| | - Raul A Laumann
- Embrapa Genetic Resources and Biotechnology, Brasília, 70770-917, Brazil
| | - John A Pickett
- Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
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Affiliation(s)
- Derek R. J. Laws
- Brewing Research Foundation, Nutfield, Surrey, RH1 4HY, Great Britain
| | - Nigel A. Bath
- Brewing Research Foundation, Nutfield, Surrey, RH1 4HY, Great Britain
| | - John A. Pickett
- Brewing Research Foundation, Nutfield, Surrey, RH1 4HY, Great Britain
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Laws DRJ, Peppard TL, Sharpe FR, Pickett JA. Recent Developments in Imparting Hop Character to Beer. Journal of the American Society of Brewing Chemists 2018. [DOI: 10.1094/asbcj-36-0069] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Derek R. J. Laws
- Brewing Research Foundation, Nutfield, Surrey, Great Britain RH1 4HY
| | | | - F. Richard Sharpe
- Brewing Research Foundation, Nutfield, Surrey, Great Britain RH1 4HY
| | - John A. Pickett
- Brewing Research Foundation, Nutfield, Surrey, Great Britain RH1 4HY
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Koczor S, Szentkirályi F, Vuts J, Caulfield JC, Withall DM, Pickett JA, Birkett MA, Tóth M. Conspecific and Heterogeneric Lacewings Respond to (Z)-4-Tridecene Identified from Chrysopa formosa (Neuroptera: Chrysopidae). J Chem Ecol 2018; 44:137-146. [PMID: 29374366 DOI: 10.1007/s10886-017-0920-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 11/20/2017] [Accepted: 12/18/2017] [Indexed: 10/18/2022]
Abstract
Green lacewings (Chrysopidae) are predators of soft-bodied pest insects and are among the most important biological control agents in crop protection. Chrysopa spp. are of special importance since, unlike most green lacewing species, adults are also predatory. The current study was undertaken in search of Chrysopa formosa compounds with semiochemical activity. Using coupled gas chromatography-electroantennography (GC-EAG), head and thorax extracts of C. formosa elicited EAG responses to a compound subsequently identified by coupled GC/mass spectrometry, microchemistry, chemical synthesis and GC peak enhancement as (Z)-4-tridecene. In field experiments, this compound decreased attraction of adult C. formosa to (1R,4aS,7S,7aR)-nepetalactol and that of Chrysoperla carnea species-complex to a ternary floral lure, with the inhibitory effect found to be dose-dependent. Our results suggest that (Z)-4-tridecene may serve as a general warning signal among multiple green lacewing species. Perspectives for potential practical applications are discussed.
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Affiliation(s)
- Sándor Koczor
- Plant Protection Institute, Centre for Agricultural Research, HAS, H-1022 Herman Ottó u. 15, Budapest, Hungary.
| | - Ferenc Szentkirályi
- Plant Protection Institute, Centre for Agricultural Research, HAS, H-1022 Herman Ottó u. 15, Budapest, Hungary
| | - József Vuts
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - John C Caulfield
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - David M Withall
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - John A Pickett
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Michael A Birkett
- Department of Biointeractions and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Miklós Tóth
- Plant Protection Institute, Centre for Agricultural Research, HAS, H-1022 Herman Ottó u. 15, Budapest, Hungary
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Li F, Li W, Lin YJ, Pickett JA, Birkett MA, Wu K, Wang G, Zhou JJ. Expression of lima bean terpene synthases in rice enhances recruitment of a beneficial enemy of a major rice pest. Plant Cell Environ 2018; 41:111-120. [PMID: 28370092 DOI: 10.1111/pce.12959] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 03/20/2017] [Accepted: 03/24/2017] [Indexed: 05/08/2023]
Abstract
Volatile terpenoids play a key role in plant defence against herbivory by attracting parasitic wasps. We identified seven terpene synthase genes from lima bean, Phaseolus lunatus L. following treatment with either the elicitor alamethicin or spider mites, Tetranychus cinnabarinus. Four of the genes (Pltps2, Pltps3, Pltps4 and Pltps5) were up-regulated with their derived proteins phylogenetically clustered in the TPS-g subfamily and PlTPS3 positioned at the base of this cluster. Recombinant PlTPS3 was able to convert geranyl diphosphate and farnesyl diphosphate to linalool and (E)-nerolidol, the latter being precursor of the homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT). Recombinant PlTPS4 showed a different substrate specificity and produced linalool and (E)-nerolidol, as well as (E,E)-geranyllinalool from geranylgeranyl diphosphate. Transgenic rice expressing Pltps3 emitted significantly more (S)-linalool and DMNT than wild-type plants, whereas transgenic rice expressing Pltps4 produced (S)-linalool, DMNT and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT). In laboratory bioassays, female Cotesia chilonis, the natural enemy of the striped rice stemborer, Chilo suppressalis, were significantly attracted to the transgenic plants and their volatiles. We further confirmed this with synthetic blends mimicking natural rice volatile composition. Our study demonstrates that the transformation of rice to produce volatile terpenoids has the potential to enhance plant indirect defence through natural enemy recruitment.
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Affiliation(s)
- Fengqi Li
- Institute of Plant Protection, Chinese Academy of Agricultural Science, No. 2 West Yuanmingyuan Road, Haidian District, Beijing, 100193, China
- Institute of Plant and Environment Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, China
| | - Wei Li
- Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan, Hubei Province, 430070, China
| | - Yong-Jun Lin
- Huazhong Agricultural University, No. 1 Shizishan Street, Hongshan District, Wuhan, Hubei Province, 430070, China
| | - John A Pickett
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Michael A Birkett
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Kongming Wu
- Institute of Plant Protection, Chinese Academy of Agricultural Science, No. 2 West Yuanmingyuan Road, Haidian District, Beijing, 100193, China
| | - Guirong Wang
- Institute of Plant Protection, Chinese Academy of Agricultural Science, No. 2 West Yuanmingyuan Road, Haidian District, Beijing, 100193, China
| | - Jing-Jiang Zhou
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
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Saini RK, Orindi BO, Mbahin N, Andoke JA, Muasa PN, Mbuvi DM, Muya CM, Pickett JA, Borgemeister CW. Protecting cows in small holder farms in East Africa from tsetse flies by mimicking the odor profile of a non-host bovid. PLoS Negl Trop Dis 2017; 11:e0005977. [PMID: 29040267 PMCID: PMC5659797 DOI: 10.1371/journal.pntd.0005977] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Revised: 10/27/2017] [Accepted: 09/20/2017] [Indexed: 01/25/2023] Open
Abstract
Background For the first time, differential attraction of pathogen vectors to vertebrate animals is investigated for novel repellents which when applied to preferred host animals turn them into non-hosts thereby providing a new paradigm for innovative vector control. For effectively controlling tsetse flies (Glossina spp.), vectors of African trypanosomosis, causing nagana, repellents more powerful than plant derived, from a non-host animal the waterbuck, Kobus ellipsiprymnus defassa, have recently been identified. Here we investigate these repellents in the field to protect cattle from nagana by making cattle as unattractive as the buck. Methodology/Principal findings To dispense the waterbuck repellents comprising guaiacol, geranylacetone, pentanoic acid and δ-octalactone, (patent application) we developed an innovative collar-mounted release system for individual cattle. We tested protecting cattle, under natural tsetse challenge, from tsetse transmitted nagana in a large field trial comprising 1,100 cattle with repellent collars in Kenya for 24 months. The collars provided substantial protection to livestock from trypanosome infection by reducing disease levels >80%. Protected cattle were healthier, showed significantly reduced disease levels, higher packed cell volume and significantly increased weight. Collars >60% reduced trypanocide use, 72.7% increase in ownership of oxen per household and enhanced traction power (protected animals ploughed 66% more land than unprotected). Land under cultivation increased by 73.4%. Increase in traction power of protected animals reduced by 69.1% acres tilled by hand per household per ploughing season. Improved food security and household income from very high acceptance of collars (99%) motivated the farmers to form a registered community based organization promoting collars for integrated tsetse control and their commercialization. Conclusion/Significance Clear demonstration that repellents from un-preferred hosts prevent contact between host and vector, thereby preventing disease transmission: a new paradigm for vector control. Evidence that deploying water buck repellents converts cattle into non-hosts for tsetse flies—‘cows in waterbuck clothing’. We investigated the potential of non-host odors from un-preferred animals, i.e. not fed upon, related to cattle, the waterbuck (Kobus ellipsiprymnus defassa) which are common in tsetse habitats for their efficacy to protect cattle from tsetse flies that transmit nagana to cattle in Africa. The identified waterbuck repellent compounds comprising of geranylacetone, pentanoic acid, guaiacol and δ-octalactone (patent application) were dispensed on cattle (hosts) using innovative repellent dispensers that individual cattle wear encircling their necks. This study, which is the first of its kind, shows that the waterbuck repellent compounds can provide substantial protection to cattle from trypanosome infections by reducing disease levels >80% in protected animals. Thus, by mimicking the odor profile of waterbucks, ‘cows in waterbuck clothing’ are essentially turned into non-hosts for tsetse flies and thus provide a new paradigm for innovative vector control. In our trial, protection of cattle with the repellent collars resulted in considerably improved food security as a result of significant reduction in trypanocide use, improved health of the protected animals which enhanced traction power with more land being brought under cultivation. Farmers’ perceptions of the repellent collars are very positive and socioeconomic studies indicate that adoption potential is extremely high.
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Affiliation(s)
- Rajinder K. Saini
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Pestinix-International Pest & Vector Control Specialists, Nairobi, Kenya
- * E-mail: ,
| | - Benedict O. Orindi
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- African Population and Health Research Center (APHRC), Nairobi, Kenya
| | - Norber Mbahin
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Africa Union–Interafrican Bureau for Animal Resources (AU-IBAR), Nairobi, Kenya
| | - John A. Andoke
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Peter N. Muasa
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - David M. Mbuvi
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Caroline M. Muya
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | | | - Christian W. Borgemeister
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Center for Development Research (ZEF), University of Bonn, Bonn, Germany
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Midega CA, Wasonga CJ, Hooper AM, Pickett JA, Khan ZR. Drought-tolerant Desmodium species effectively suppress parasitic striga weed and improve cereal grain yields in western Kenya. Crop Prot 2017; 98:94-101. [PMID: 28775391 PMCID: PMC5465939 DOI: 10.1016/j.cropro.2017.03.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/14/2017] [Accepted: 03/17/2017] [Indexed: 05/04/2023]
Abstract
The parasitic weed Striga hermonthica Benth. (Orobanchaceae), commonly known as striga, is an increasingly important constraint to cereal production in sub-Saharan Africa (SSA), often resulting in total yield losses in maize (Zea mays L.) and substantial losses in sorghum (Sorghum bicolor (L.) Moench). This is further aggravated by soil degradation and drought conditions that are gradually becoming widespread in SSA. Forage legumes in the genus Desmodium (Fabaceae), mainly D. uncinatum and D. intortum, effectively control striga and improve crop productivity in SSA. However, negative effects of climate change such as drought stress is affecting the functioning of these systems. There is thus a need to identify and characterize new plants possessing the required ecological chemistry to protect crops against the biotic stress of striga under such environmental conditions. 17 accessions comprising 10 species of Desmodium were screened for their drought stress tolerance and ability to suppress striga. Desmodium incanum and D. ramosissimum were selected as the most promising species as they retained their leaves and maintained leaf function for longer periods during their exposure to drought stress conditions. They also had desirable phenotypes with more above ground biomass. The two species suppressed striga infestation, both under controlled and field conditions, and resulted in significant grain yield increases, demonstrating the incremental capability of Desmodium species in striga suppression. These results demonstrate beneficial effects of Desmodium species in enhancing cereal productivity in dry areas.
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Affiliation(s)
- Charles A.O. Midega
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi 00100, Kenya
| | - Charles J. Wasonga
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi 00100, Kenya
| | - Antony M. Hooper
- Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK
| | - John A. Pickett
- Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK
| | - Zeyaur R. Khan
- International Centre of Insect Physiology and Ecology (icipe), P.O. Box 30772, Nairobi 00100, Kenya
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Tamiru A, Bruce TJA, Richter A, Woodcock CM, Midega CAO, Degenhardt J, Kelemu S, Pickett JA, Khan ZR. A maize landrace that emits defense volatiles in response to herbivore eggs possesses a strongly inducible terpene synthase gene. Ecol Evol 2017; 7:2835-2845. [PMID: 28428873 PMCID: PMC5395458 DOI: 10.1002/ece3.2893] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 01/21/2017] [Accepted: 01/28/2017] [Indexed: 12/29/2022] Open
Abstract
Maize (Zea mays) emits volatile terpenes in response to insect feeding and egg deposition to defend itself against harmful pests. However, maize cultivars differ strongly in their ability to produce the defense signal. To further understand the agroecological role and underlying genetic mechanisms for variation in terpene emission among maize cultivars, we studied the production of an important signaling component (E)-caryophyllene in a South American maize landrace Braz1006 possessing stemborer Chilo partellus egg inducible defense trait, in comparison with the European maize line Delprim and North American inbred line B73. The (E)-caryophyllene production level and transcript abundance of TPS23, terpene synthase responsible for (E)-caryophyllene formation, were compared between Braz1006, Delprim, and B73 after mimicked herbivory. Braz1006-TPS23 was heterologously expressed in E. coli, and amino acid sequences were determined. Furthermore, electrophysiological and behavioral responses of a key parasitic wasp Cotesia sesamiae to C. partellus egg-induced Braz1006 volatiles were determined using coupled gas chromatography electroantennography and olfactometer bioassay studies. After elicitor treatment, Braz1006 released eightfold higher (E)-caryophyllene than Delprim, whereas no (E)-caryophyllene was detected in B73. The superior (E)-caryophyllene production by Braz1006 was positively correlated with high transcript levels of TPS23 in the landrace compared to Delprim. TPS23 alleles from Braz1006 showed dissimilarities at different sequence positions with Delprim and B73 and encodes an active enzyme. Cotesia sesamiae was attracted to egg-induced volatiles from Braz1006 and synthetic (E)-caryophyllene. The variation in (E)-caryophyllene emission between Braz1006 and Delprim is positively correlated with induced levels of TPS23 transcripts. The enhanced TPS23 activity and corresponding (E)-caryophyllene production by the maize landrace could be attributed to the differences in amino acid sequence with the other maize lines. This study suggested that the same analogous genes could have contrasting expression patterns in different maize genetic backgrounds. The current findings provide valuable insight not only into genetic mechanisms underlying variation in defense signal production but also the prospect of introgressing the novel defense traits into elite maize varieties for effective and ecologically sound protection of crops against damaging insect pests.
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Affiliation(s)
- Amanuel Tamiru
- International Centre of Insect Physiology and Ecology (ICIPE)NairobiKenya
| | - Toby J. A. Bruce
- Department of Biological Chemistry and Crop ProtectionRothamsted ResearchHarpendenUK
| | - Annett Richter
- Institute of PharmacyMartin Luther University HalleHalle (Saale)Germany
- Boyce Thompson InstituteIthacaNYUSA
| | - Christine M. Woodcock
- Department of Biological Chemistry and Crop ProtectionRothamsted ResearchHarpendenUK
| | | | - Jörg Degenhardt
- Institute of PharmacyMartin Luther University HalleHalle (Saale)Germany
| | - Segenet Kelemu
- International Centre of Insect Physiology and Ecology (ICIPE)NairobiKenya
| | - John A. Pickett
- Department of Biological Chemistry and Crop ProtectionRothamsted ResearchHarpendenUK
| | - Zeyaur R. Khan
- International Centre of Insect Physiology and Ecology (ICIPE)NairobiKenya
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O'Shea B, Wadsworth S, Pino Marambio J, Birkett MA, Pickett JA, Mordue Luntz AJ. Disruption of host-seeking behaviour by the salmon louse, Lepeophtheirus salmonis, using botanically derived repellents. J Fish Dis 2017; 40:495-505. [PMID: 27496636 DOI: 10.1111/jfd.12526] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 06/07/2016] [Accepted: 06/08/2016] [Indexed: 06/06/2023]
Abstract
The potential for developing botanically derived natural products as novel feed-through repellents for disrupting settlement of the salmon louse, Lepeophtheirus salmonis (Caligidae) upon farmed Atlantic salmon, Salmo salar, was investigated using an established laboratory vertical Y-tube behavioural bioassay for assessing copepodid behaviour. Responses to artificial sea water conditioned with the odour of salmon, or to the known salmon-derived kairomone component, α-isophorone, in admixture with selected botanical materials previously known to interfere with invertebrate arthropod host location were recorded. Materials included oils extracted from garlic, Allium sativum (Amaryllidaceae), rosemary, Rosmarinus officinalis (Lamiaceae), lavender, Lavandula angustifolia (Lamiaceae), and bog myrtle, Myrica gale (Myricaceae), and individual components (diallyl sulphide and diallyl disulphide from garlic; allyl, propyl, butyl, 4-pentenyl and 2-phenylethyl isothiocyanate from plants in the Brassica genus). Removal of attraction to salmon-conditioned water (SCW) or α-isophorone was observed when listed materials were presented at extremely low parts per trillion (ppt), that is picograms per litre or 10-12 level. Significant masking of attraction to SCW was observed at a level of 10 ppt for diallyl disulphide and diallyl sulphide, and allyl isothiocyanate and butyl isothiocyanate. The potential of very low concentrations of masking compounds to disrupt Le. salmonis copepodid settlement on a host fish has been demonstrated in vitro.
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Affiliation(s)
- B O'Shea
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
| | | | | | - M A Birkett
- Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Herts., UK
| | - J A Pickett
- Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Herts., UK
| | - A J Mordue Luntz
- School of Biological Sciences, University of Aberdeen, Aberdeen, UK
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De Keyser R, Cassidy C, Laban S, Gopal P, Pickett JA, Reddy YK, Prasad M, Prasad G, Chirukandoth S, Senthilven K, Carpenter S, Logan JG. Insecticidal effects of deltamethrin in laboratory and field populations of Culicoides species: how effective are host-contact reduction methods in India? Parasit Vectors 2017; 10:54. [PMID: 28143560 PMCID: PMC5286563 DOI: 10.1186/s13071-017-1992-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 01/19/2017] [Indexed: 11/15/2022] Open
Abstract
Background Bluetongue virus (BTV) is transmitted by Culicoides biting midges and causes bluetongue (BT), a clinical disease observed primarily in sheep. BT has a detrimental effect on subsistence farmers in India, where hyperendemic outbreaks impact on smallholdings in the southern states of the country. In this study, we establish a reliable method for testing the toxic effects of deltamethrin on Culicoides and then compare deltamethrin with traditional control methods used by farmers in India. Results Effects of deltamethrin were initially tested using a colonised strain of Culicoides nubeculosus Meigen and a modified World Health Organisation exposure assay. This method was then applied to field populations of Culicoides spp. in India. The field population of C. oxystoma in India had a greater LC50 (0.012 ± 0.009%) for deltamethrin than laboratory-reared C.nubeculosus (0.0013 ± 0.0002%). Exposure of C. nubeculosus to deltamethrin at higher ambient temperatures resulted in greater rates of knockdown but a lower mortality rate at 24 h post-exposure. Behavioural assays with C. nubeculosus in WHO tubes provided evidence for contact irritancy and spatial repellence caused by deltamethrin. The field experiments in India, however, provided no evidence for repellent or toxic effects of deltamethrin. Traditional methods such as the application of neem oil and burning of neem leaves also provided no protection. Conclusions Our study demonstrates that field-collected Culicoides in India are less susceptible to deltamethrin exposure than laboratory-bred C. nubeculosus and traditional methods of insect control do not provide protection to sheep. These low levels of susceptibility to deltamethrin have not been recorded before in field populations of Culicoides and suggest resistance to synthetic pyrethrioids. Alternative insect control methods, in addition to vaccination, may be needed to protect Indian livestock from BTV transmission. Electronic supplementary material The online version of this article (doi:10.1186/s13071-017-1992-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rien De Keyser
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Clare Cassidy
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Swathi Laban
- Vaccine Research Centre-Viral Vaccines, Centre for Animal Health Studies, Tamil Nadu Veterinary and Animal Sciences University, Madhavaram Milk Colony, Chennai, 600 051, India
| | - Prakash Gopal
- Vaccine Research Centre-Viral Vaccines, Centre for Animal Health Studies, Tamil Nadu Veterinary and Animal Sciences University, Madhavaram Milk Colony, Chennai, 600 051, India
| | - John A Pickett
- Rothamsted Research, West Common, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Yarabolu K Reddy
- Vaccine Research Centre-Viral Vaccines, Centre for Animal Health Studies, Tamil Nadu Veterinary and Animal Sciences University, Madhavaram Milk Colony, Chennai, 600 051, India
| | - Minakshi Prasad
- Department of Animal Biotechnology, College of Veterinary Science, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, 125004, Haryana, India
| | - Gaya Prasad
- Indian Council of Agricultural Research, New Delhi, 110 001, India
| | | | | | - Simon Carpenter
- Vector-borne viral diseases Programme, The Pirbright Institute, Ash Road, Woking, GU24 0NF, UK
| | - James G Logan
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
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Sobhy IS, Woodcock CM, Powers SJ, Caulfield JC, Pickett JA, Birkett MA. cis-Jasmone Elicits Aphid-Induced Stress Signalling in Potatoes. J Chem Ecol 2017; 43:39-52. [PMID: 28130741 PMCID: PMC5331074 DOI: 10.1007/s10886-016-0805-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 10/16/2016] [Accepted: 12/02/2016] [Indexed: 11/30/2022]
Abstract
Elicitation of plant defense signaling that results in altered emission of volatile organic compounds (VOCs) offers opportunities for protecting plants against arthropod pests. In this study, we treated potato, Solanum tuberosum L., with the plant defense elicitor cis-jasmone (CJ), which induces the emission of defense VOCs and thus affects the behavior of herbivores. Using chemical analysis, electrophysiological and behavioral assays with the potato-feeding aphid Macrosiphum euphorbiae, we showed that CJ treatment substantially increased the emission of defense VOCs from potatoes compared to no treatment. Coupled GC-electroantennogram (GC-EAG) recordings from the antennae of M. euphorbiae showed robust responses to 14 compounds present in induced VOCs, suggesting their behavioral role in potato/aphid interactions. Plants treated with CJ and then challenged with M. euphorbiae were most repellent to alate M. euphorbiae. Principal component analysis (PCA) of VOC collections suggested that (E)-2-hexenal, (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT), (E)-β-farnesene, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), methyl salicylate (MeSA), CJ, and methyl benzoate (MeBA) were the main VOCs contributing to aphid behavioral responses, and that production of TMTT, (E)-β-farnesene, CJ, and DMNT correlated most strongly with aphid repellency. Our findings confirm that CJ can enhance potato defense against aphids by inducing production of VOCs involved in aphid-induced signalling.
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Affiliation(s)
- Islam S Sobhy
- Rothamsted Research, West Common, Harpenden, AL5 2JQ, Hertfordshire, UK.,Department of Plant Protection, Public Service Center of Biological Control (PSCBC), Faculty of Agriculture, Suez Canal University, Ismailia, 41522, Egypt.,Department of Microbial & Molecular Systems, KU Leuven, Campus De Nayer, B-2860 Sint-Katelijne-Waver, Leuven, Belgium
| | | | - Stephen J Powers
- Rothamsted Research, West Common, Harpenden, AL5 2JQ, Hertfordshire, UK
| | - John C Caulfield
- Rothamsted Research, West Common, Harpenden, AL5 2JQ, Hertfordshire, UK
| | - John A Pickett
- Rothamsted Research, West Common, Harpenden, AL5 2JQ, Hertfordshire, UK
| | - Michael A Birkett
- Rothamsted Research, West Common, Harpenden, AL5 2JQ, Hertfordshire, UK.
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45
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de Oliveira Filho JG, Ferreira LL, Sarria ALF, Pickett JA, Birkett MA, Mascarin GM, de León AAP, Borges LMF. Brown dog tick, Rhipicephalus sanguineus sensu lato, infestation of susceptible dog hosts is reduced by slow release of semiochemicals from a less susceptible host. Ticks Tick Borne Dis 2017; 8:139-145. [DOI: 10.1016/j.ttbdis.2016.10.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 10/19/2016] [Accepted: 10/23/2016] [Indexed: 11/27/2022]
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Pickett JA, Khan ZR. Plant volatile-mediated signalling and its application in agriculture: successes and challenges. New Phytol 2016; 212:856-870. [PMID: 27874990 DOI: 10.1111/nph.14274] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 08/04/2016] [Indexed: 05/25/2023]
Abstract
856 I. 856 II. 857 III. 858 IV. 859 V. 860 VI. 862 VII. 863 VIII. 864 IX. 866 866 References 866 SUMMARY: The mediation of volatile secondary metabolites in signalling between plants and other organisms has long been seen as presenting opportunities for sustainable crop protection. Initially, exploitation of interactions between plants and other organisms, particularly insect pests, foundered because of difficulties in delivering, sustainably, the signal systems for crop protection. We now have mounting and, in some cases, clear practical evidence for successful delivery by companion cropping or next-generation genetic modification (GM). At the same time, the type of plant signalling being exploited has expanded to signalling from plants to organisms antagonistic to pests, and to plant stress-induced, or primed, plant-to-plant signalling for defence and growth stimulation.
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Affiliation(s)
- John A Pickett
- Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, UK
| | - Zeyaur R Khan
- Push-Pull Programme, International Centre of Insect Physiology and Ecology, PO Box 30, Mbita, 40305, Kenya
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da Graça JP, Ueda TE, Janegitz T, Vieira SS, Salvador MC, de Oliveira MCN, Zingaretti SM, Powers SJ, Pickett JA, Birkett MA, Hoffmann-Campo CB. The natural plant stress elicitor cis-jasmone causes cultivar-dependent reduction in growth of the stink bug, Euschistus heros and associated changes in flavonoid concentrations in soybean, Glycine max. Phytochemistry 2016; 131:84-91. [PMID: 27659594 PMCID: PMC5055112 DOI: 10.1016/j.phytochem.2016.08.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 06/22/2016] [Accepted: 08/29/2016] [Indexed: 05/12/2023]
Abstract
To test the hypothesis that the plant stress related elicitor cis-jasmone (cJ) provides protection in soybean pods against the seed-sucking stink bug pest, Euschistus heros, the growth of E. heros on cJ-treated pods was investigated using three soybean cultivars differing in insect susceptibility, i.e. BRS 134 (susceptible), IAC 100 (resistant) and Dowling (resistant). E. heros showed reduced weight gain when fed cJ-treated Dowling, whereas no effect on weight gain was observed when fed other treated cultivars. Using analysis of variance, a three factor (cultivar x treatment x time) interaction was observed with concentrations of the flavonoid glycosides daidzin and genistin, and their corresponding aglycones, daidzein and genistein. There were increases in genistein and genistin concentrations in cJ-treated Dowling at 144 and 120 h post treatment, respectively. Higher concentrations of malonyldaidzin and malonylgenistin in Dowling, compared to BRS 134 and IAC 100, were observed independently of time, the highest concentrations being observed in cJ-treated seeds. Levels of glycitin and malonylglycitin were higher in BRS 134 and IAC 100 compared to Dowling. Canonical variate analysis indicated daidzein (in the first two canonical variates) and genistein (in the first only) as important discriminatory variables. These results suggest that cJ treatment leads to an increase in the levels of potentially defensive isoflavonoids in immature soybean seeds, but the negative effect upon E. heros performance is cultivar-dependent.
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Affiliation(s)
- José P da Graça
- Embrapa Centro Nacional de Pesquisa de Soja, Caixa Postal: 231, CEP. 86001-970, Londrina, PR, Brazil; UNESP Universidade Estadual Paulista, FCAV, Via de Acesso Prof. Paulo Donato Castellane, s/n, CEP. 14884-900, Jaboticabal, SP, Brazil
| | - Tatiana E Ueda
- Embrapa Centro Nacional de Pesquisa de Soja, Caixa Postal: 231, CEP. 86001-970, Londrina, PR, Brazil; UEL Universidade Estadual de Londrina, Rodovia Celso Garcia Cid, PR 445 Km 380, Caixa Postal 6001, CEP. 86051-980, Londrina, PR, Brazil
| | - Tatiani Janegitz
- Embrapa Centro Nacional de Pesquisa de Soja, Caixa Postal: 231, CEP. 86001-970, Londrina, PR, Brazil; UEM Universidade Estadual de Maringá, Avenida Colombo, 5790, Jardim Universitario, CEP. 87020-900, Maringá, PR, Brazil
| | - Simone S Vieira
- Embrapa Centro Nacional de Pesquisa de Soja, Caixa Postal: 231, CEP. 86001-970, Londrina, PR, Brazil; IAC Instituto Agronômico de Campinas, Av. Barão de Itapura, 1481, Cx. Postal: 28, CEP. 13012-970, Campinas, SP, Brazil
| | - Mariana C Salvador
- Embrapa Centro Nacional de Pesquisa de Soja, Caixa Postal: 231, CEP. 86001-970, Londrina, PR, Brazil; UEL Universidade Estadual de Londrina, Rodovia Celso Garcia Cid, PR 445 Km 380, Caixa Postal 6001, CEP. 86051-980, Londrina, PR, Brazil
| | - Maria C N de Oliveira
- Embrapa Centro Nacional de Pesquisa de Soja, Caixa Postal: 231, CEP. 86001-970, Londrina, PR, Brazil
| | - Sonia M Zingaretti
- UNAERP Universidade de Ribeirão Preto, Avenida Costábile Romano, Caixa Postal: 2201, CEP. 14096-900, Ribeirão Preto, SP, Brazil
| | - Stephen J Powers
- Computational and Systems Biology Department, Rothamsted Research, Harpenden, Herts. AL5 2JQ, United Kingdom
| | - John A Pickett
- Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Herts. AL5 2JQ, United Kingdom
| | - Michael A Birkett
- Biological Chemistry and Crop Protection Department, Rothamsted Research, Harpenden, Herts. AL5 2JQ, United Kingdom
| | - Clara B Hoffmann-Campo
- Embrapa Centro Nacional de Pesquisa de Soja, Caixa Postal: 231, CEP. 86001-970, Londrina, PR, Brazil.
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Hassemer MJ, Sant'Ana J, Borges M, Withall D, Pickett JA, de Oliveira MWM, Laumann RA, Birkett MA, Blassioli-Moraes MC. Revisiting the Male-Produced Aggregation Pheromone of the Lesser Mealworm, Alphitobius diaperinus (Coleoptera, Tenebrionidae): Identification of a Six-Component Pheromone from a Brazilian Population. J Agric Food Chem 2016; 64:6809-18. [PMID: 27494353 DOI: 10.1021/acs.jafc.6b02235] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The lesser mealworm, Alphitobius diaperinus Panzer 1797 (Coleoptera: Tenebrionidae), is a cosmopolitan insect pest affecting poultry production. Due to its cryptic behavior, insecticide control is usually not efficient. Thus, sustainable and effective methods would have an enormous and positive impact in poultry production. The aim of this study was to confirm the identity of the male-produced aggregation pheromone for a Brazilian population of A. diaperinus and to evaluate its biological activity in behavioral assays. Six male-specific compounds were identified: (R)-limonene (1), (E)-ocimene (2), 2-nonanone (3), (S)-linalool (4), (R)-daucene (5), all described before in an American population, and a sixth component, (E,E)-α-farnesene (6), which is apparently exclusive to a Brazilian population. Y-Tube bioassays confirmed the presence of a male-produced aggregation pheromone and showed that all components need to be present in a similar ratio and concentration as emitted by male A. diaperinus to produce a positive chemotactic response.
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Affiliation(s)
- Marla J Hassemer
- UnB - Universidade de Brası́lia , Departamento de Zoologia, Campus Universitário Darcy Ribeiro, Brası́lia, DF 70910-900, Brazil
- Universidade Federal do Rio Grande do Sul , PPG-Fitotecnia, Avenida Bento Gonçalves, 7712 Porto Alegre, RS 90040-060, Brazil
- EMBRAPA Recursos Genéticos e Biotecnologia , Parque Estação Biológica, W5 Norte, 70770-917 Brası́lia, Brazil
| | - Josué Sant'Ana
- Universidade Federal do Rio Grande do Sul , PPG-Fitotecnia, Avenida Bento Gonçalves, 7712 Porto Alegre, RS 90040-060, Brazil
| | - Miguel Borges
- EMBRAPA Recursos Genéticos e Biotecnologia , Parque Estação Biológica, W5 Norte, 70770-917 Brası́lia, Brazil
| | - David Withall
- Biological Chemistry and Crop Protection Department, Rothamsted Research , Harpenden, Herts AL5 2JQ, United Kingdom
| | - John A Pickett
- Biological Chemistry and Crop Protection Department, Rothamsted Research , Harpenden, Herts AL5 2JQ, United Kingdom
| | - Márcio W M de Oliveira
- EMBRAPA Recursos Genéticos e Biotecnologia , Parque Estação Biológica, W5 Norte, 70770-917 Brası́lia, Brazil
| | - Raul A Laumann
- EMBRAPA Recursos Genéticos e Biotecnologia , Parque Estação Biológica, W5 Norte, 70770-917 Brası́lia, Brazil
| | - Michael A Birkett
- Biological Chemistry and Crop Protection Department, Rothamsted Research , Harpenden, Herts AL5 2JQ, United Kingdom
| | - Maria C Blassioli-Moraes
- EMBRAPA Recursos Genéticos e Biotecnologia , Parque Estação Biológica, W5 Norte, 70770-917 Brası́lia, Brazil
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Groen SC, Jiang S, Murphy AM, Cunniffe NJ, Westwood JH, Davey MP, Bruce TJA, Caulfield JC, Furzer OJ, Reed A, Robinson SI, Miller E, Davis CN, Pickett JA, Whitney HM, Glover BJ, Carr JP. Virus Infection of Plants Alters Pollinator Preference: A Payback for Susceptible Hosts? PLoS Pathog 2016; 12:e1005790. [PMID: 27513727 PMCID: PMC4981420 DOI: 10.1371/journal.ppat.1005790] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 07/06/2016] [Indexed: 11/18/2022] Open
Abstract
Plant volatiles play important roles in attraction of certain pollinators and in host location by herbivorous insects. Virus infection induces changes in plant volatile emission profiles, and this can make plants more attractive to insect herbivores, such as aphids, that act as viral vectors. However, it is unknown if virus-induced alterations in volatile production affect plant-pollinator interactions. We found that volatiles emitted by cucumber mosaic virus (CMV)-infected tomato (Solanum lycopersicum) and Arabidopsis thaliana plants altered the foraging behaviour of bumblebees (Bombus terrestris). Virus-induced quantitative and qualitative changes in blends of volatile organic compounds emitted by tomato plants were identified by gas chromatography-coupled mass spectrometry. Experiments with a CMV mutant unable to express the 2b RNA silencing suppressor protein and with Arabidopsis silencing mutants implicate microRNAs in regulating emission of pollinator-perceivable volatiles. In tomato, CMV infection made plants emit volatiles attractive to bumblebees. Bumblebees pollinate tomato by 'buzzing' (sonicating) the flowers, which releases pollen and enhances self-fertilization and seed production as well as pollen export. Without buzz-pollination, CMV infection decreased seed yield, but when flowers of mock-inoculated and CMV-infected plants were buzz-pollinated, the increased seed yield for CMV-infected plants was similar to that for mock-inoculated plants. Increased pollinator preference can potentially increase plant reproductive success in two ways: i) as female parents, by increasing the probability that ovules are fertilized; ii) as male parents, by increasing pollen export. Mathematical modeling suggested that over a wide range of conditions in the wild, these increases to the number of offspring of infected susceptible plants resulting from increased pollinator preference could outweigh underlying strong selection pressures favoring pathogen resistance, allowing genes for disease susceptibility to persist in plant populations. We speculate that enhanced pollinator service for infected individuals in wild plant populations might provide mutual benefits to the virus and its susceptible hosts.
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Affiliation(s)
- Simon C. Groen
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Sanjie Jiang
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Alex M. Murphy
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Nik J. Cunniffe
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Jack H. Westwood
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Matthew P. Davey
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | | | | | - Oliver J. Furzer
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Alison Reed
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Sophie I. Robinson
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Elizabeth Miller
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Christopher N. Davis
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - John A. Pickett
- Rothamsted Research, Harpenden, Hertfordshire, United Kingdom
| | - Heather M. Whitney
- University of Bristol, School of Biological Sciences, Bristol, United Kingdom
| | - Beverley J. Glover
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
| | - John P. Carr
- Department of Plant Sciences, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
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Mutyambai DM, Bruce TJA, van den Berg J, Midega CAO, Pickett JA, Khan ZR. An Indirect Defence Trait Mediated through Egg-Induced Maize Volatiles from Neighbouring Plants. PLoS One 2016; 11:e0158744. [PMID: 27392034 PMCID: PMC4938388 DOI: 10.1371/journal.pone.0158744] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 06/21/2016] [Indexed: 11/18/2022] Open
Abstract
Attack of plants by herbivorous arthropods may result in considerable changes to the plant's chemical phenotype with respect to emission of herbivore-induced plant volatiles (HIPVs). These HIPVs have been shown to act as repellents to the attacking insects as well as attractants for the insects antagonistic to these herbivores. Plants can also respond to HIPV signals from other plants that warn them of impending attack. Recent investigations have shown that certain maize varieties are able to emit volatiles following stemborer egg deposition. These volatiles attract the herbivore's parasitoids and directly deter further oviposition. However, it was not known whether these oviposition-induced maize (Zea mays, L.) volatiles can mediate chemical phenotypic changes in neighbouring unattacked maize plants. Therefore, this study sought to investigate the effect of oviposition-induced maize volatiles on intact neighbouring maize plants in 'Nyamula', a landrace known to respond to oviposition, and a standard commercial hybrid, HB515, that did not. Headspace volatile samples were collected from maize plants exposed to Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) egg deposition and unoviposited neighbouring plants as well as from control plants kept away from the volatile emitting ones. Behavioural bioassays were carried out in a four-arm olfactometer using egg (Trichogramma bournieri Pintureau & Babault (Hymenoptera: Trichogrammatidae)) and larval (Cotesia sesamiae Cameron (Hymenoptera: Braconidae)) parasitoids. Coupled Gas Chromatography-Mass Spectrometry (GC-MS) was used for volatile analysis. For the 'Nyamula' landrace, GC-MS analysis revealed HIPV production not only in the oviposited plants but also in neighbouring plants not exposed to insect eggs. Higher amounts of EAG-active biogenic volatiles such as (E)-4,8-dimethyl-1,3,7-nonatriene were emitted from these plants compared to control plants. Subsequent behavioural assays with female T. bournieri and C. sesamiae parasitic wasps indicated that these parasitoids preferred volatiles from oviposited and neighbouring landrace plants compared to those from the control plants. This effect was absent in the standard commercial hybrid we tested. There was no HIPV induction and no difference in parasitoid attraction in neighbouring and control hybrid maize plants. These results show plant-plant signalling: 'Nyamula' maize plants emitting oviposition-induced volatiles attractive to the herbivore's natural enemies can induce this indirect defence trait in conspecific neighbouring undamaged maize plants. Maize plants growing in a field may thus benefit from this indirect defence through airborne signalling which may enhance the fitness of the volatile-emitting plant by increasing predation pressure on herbivores.
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Affiliation(s)
- Daniel M. Mutyambai
- Habitat Management Programme, International Centre of Insect Physiology and Ecology, P.O Box 30–40305, Mbita, Kenya
- Biology Department, South Eastern Kenya University, P.O. Box 170–90200, Kitui, Kenya
| | - Toby J. A. Bruce
- Department of Biological Chemistry, Rothamsted Research, Harpenden, Herts, AL5 2JQ, United Kingdom
| | - Johnnie van den Berg
- School of Biological Sciences, North-West University, Potchefstroom, 2520, South Africa
| | - Charles A. O. Midega
- Habitat Management Programme, International Centre of Insect Physiology and Ecology, P.O Box 30–40305, Mbita, Kenya
| | - John A. Pickett
- Department of Biological Chemistry, Rothamsted Research, Harpenden, Herts, AL5 2JQ, United Kingdom
| | - Zeyaur R. Khan
- Habitat Management Programme, International Centre of Insect Physiology and Ecology, P.O Box 30–40305, Mbita, Kenya
- School of Biological Sciences, North-West University, Potchefstroom, 2520, South Africa
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