The Experts below are selected from a list of 954 Experts worldwide ranked by ideXlab platform
John C. Caulfield - One of the best experts on this subject based on the ideXlab platform.
-
2r 5s theaspirane identified as the kairomone for the banana weevil cosmopolites sordidus from attractive senesced leaves of the host banana musa spp
Chemistry: A European Journal, 2018Co-Authors: John C. Caulfield, Christine M. Woodcock, Samson Abah Abagale, Antony M. Hooper, David M. Withall, Keith Chamberlain, Samuel Osafo Acquaah, Helmut F. Van Emden, Haruna BraimahAbstract: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.
-
(2R,5S)‐Theaspirane Identified as the Kairomone for the Banana Weevil, Cosmopolites sordidus, from Attractive Senesced Leaves of the Host Banana, Musa spp.
Chemistry: A European Journal, 2018Co-Authors: Samson Abah Abagale, John C. Caulfield, Christine M. Woodcock, Antony M. Hooper, David M. Withall, Keith Chamberlain, Samuel Osafo Acquaah, Helmut F. Van Emden, Haruna Braimah, John A. PickettAbstract: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.
-
Conspecific and Heterogeneric Lacewings Respond to (Z)-4-Tridecene Identified from Chrysopa formosa (Neuroptera: Chrysopidae)
Journal of Chemical Ecology, 2018Co-Authors: Sandor Koczor, John C. Caulfield, Ferenc Szentkiralyi, David M. Withall, John A. Pickett, Michael A. Birkett, József Vuts, Miklos TothAbstract: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 (1 R ,4a S ,7 S ,7a R )-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.
-
electrophysiological and behavioral responses of female african rice gall midge orseolia oryzivora harris and gagne to host plant volatiles
Journal of Chemical Ecology, 2017Co-Authors: E. O. Ogah, John C. Caulfield, J. A. Pickett, Michael A. Birkett, C M Woodcock, F. E. Nwilene, L E Smart, Toby J. A. BruceAbstract:African rice gall midge, Orseolia oryzivora Harris and Gagne, is a major pest of rice in Africa. Depsite its economic importance, its chemical ecology is not well understood. Here, we assessed behavioral and electrophysiological responses of O. oryzivora to host plant volatiles. In olfactometer bioassays, mated female O. oryzivora were attracted to volatiles emitted from intact rice plants but were repelled by volatiles collected from plants infested by conspecifics. In a choice test, there was a preference for volatiles from uninfested plants over those from infested plants. Coupled gas chromatography-Electroantennography analyses of panicle volatiles isolated four electrophysiologically active components: (S)-linalool, 4,8-dimethyl-1,3,7-nonatriene, (E)-caryophyllene, and (R/S)-(E)-nerolidol. A synthetic blend of volatiles at the same concentration and ratio as that from an intact plant was attractive to mated females, whereas a blend based on the ratio of volatiles from an infested plant was repellent. This suggests that O. oryzivora uses olfaction for host plant recognition. The identification of blends of volatiles emitted by plants that can both attract and repel O. oryzivora may aid the development of sustainable control measures.
-
Electrophysiological and behavioral responses of female African rice gall midge, Orseolia oryzivora Harris and Gagné, to host plant volatiles
Journal of Chemical Ecology, 2017Co-Authors: E. O. Ogah, John C. Caulfield, Christine M. Woodcock, John A. Pickett, Michael A. Birkett, F. E. Nwilene, L E Smart, Toby J. BruceAbstract:African rice gall midge, Orseolia oryzivora Harris and Gagné, is a major pest of rice in Africa. Depsite its economic importance, its chemical ecology is not well understood. Here, we assessed behavioral and electrophysiological responses of O. oryzivora to host plant volatiles. In olfactometer bioassays, mated female O. oryzivora were attracted to volatiles emitted from intact rice plants but were repelled by volatiles collected from plants infested by conspecifics. In a choice test, there was a preference for volatiles from uninfested plants over those from infested plants. Coupled gas chromatography-Electroantennography analyses of panicle volatiles isolated four electrophysiologically active components: ( S )-linalool, 4,8-dimethyl-1,3,7-nonatriene, ( E )-caryophyllene, and ( R/S )-( E )-nerolidol. A synthetic blend of volatiles at the same concentration and ratio as that from an intact plant was attractive to mated females, whereas a blend based on the ratio of volatiles from an infested plant was repellent. This suggests that O. oryzivora uses olfaction for host plant recognition. The identification of blends of volatiles emitted by plants that can both attract and repel O. oryzivora may aid the development of sustainable control measures.
J. A. Pickett - One of the best experts on this subject based on the ideXlab platform.
-
electrophysiological and behavioral responses of female african rice gall midge orseolia oryzivora harris and gagne to host plant volatiles
Journal of Chemical Ecology, 2017Co-Authors: E. O. Ogah, John C. Caulfield, J. A. Pickett, Michael A. Birkett, C M Woodcock, F. E. Nwilene, L E Smart, Toby J. A. BruceAbstract:African rice gall midge, Orseolia oryzivora Harris and Gagne, is a major pest of rice in Africa. Depsite its economic importance, its chemical ecology is not well understood. Here, we assessed behavioral and electrophysiological responses of O. oryzivora to host plant volatiles. In olfactometer bioassays, mated female O. oryzivora were attracted to volatiles emitted from intact rice plants but were repelled by volatiles collected from plants infested by conspecifics. In a choice test, there was a preference for volatiles from uninfested plants over those from infested plants. Coupled gas chromatography-Electroantennography analyses of panicle volatiles isolated four electrophysiologically active components: (S)-linalool, 4,8-dimethyl-1,3,7-nonatriene, (E)-caryophyllene, and (R/S)-(E)-nerolidol. A synthetic blend of volatiles at the same concentration and ratio as that from an intact plant was attractive to mated females, whereas a blend based on the ratio of volatiles from an infested plant was repellent. This suggests that O. oryzivora uses olfaction for host plant recognition. The identification of blends of volatiles emitted by plants that can both attract and repel O. oryzivora may aid the development of sustainable control measures.
-
semiochemicals used in host location by the coffee berry borer hypothenemus hampei
Journal of Chemical Ecology, 2009Co-Authors: Esayas Mendesil, John C. Caulfield, Emiru Seyoum, Christine M. Woodcock, Toby J. A. Bruce, J. A. PickettAbstract:The coffee berry borer, Hypothenemus hampei is a serious pest in many coffee growing countries. Electrophysiological and behavioral responses of H. hampei to volatiles of different phenological stages of coffee, Coffea arabica, fruits were studied in order to identify volatile semiochemicals used in host location. Volatiles were collected from different phenological stages of C. arabica fruit by air entrainment. Electrophysiological recordings were made from insect antennae. Behavioral assays were carried out using a Perspex four-arm olfactometer. Insects spent significantly more time in the region of the olfactometer where ripe and dry fruit volatiles were present compared to control regions. Coupled gas chromatography—Electroantennography revealed the presence of six electrophysiologically active compounds in C. arabica volatiles. These were identified by using GC and GC-MS as methylcyclohexane, ethylbenzene, nonane, 1-octen-3-ol, (R)-limonene, and (R)-3-ethyl-4-methylpentanol. In the olfactometer bioassay, H. hampei showed a significant response to 3-ethyl-4-methylpentanol, methylcyclohexane, nonane, ethylbenzene, and a synthetic blend of these four compounds. Attraction to the synthetic blend was comparable to that for the natural sample. The significance of the study is discussed in terms of semiochemical based pest management methods of the coffee berry borer.
-
identification and biological activity of sex pheromone components from females of the plum moth illiberis rotundata jordan lepidoptera zygaenidae procridinae
Chemoecology, 2009Co-Authors: Mitko Subchev, Lester J. Wadhams, J. A. Pickett, Teodora B Toshova, Chiharu Koshio, Stephan Franke, Armin Troger, Robert Twele, Wittko Francke, C M WoodcockAbstract:The plum moth, Illiberis rotundata Jordan (Lepidoptera: Zygaenidae: Procridinae), is a pest of orchards in Japan and China. Few chemical ecological studies have been directed towards the Zygaenidae and particularly the Procridinae. To investigate the sex pheromone of this species, extracts of pheromone glands from adult female I. rotundata were analyzed by coupled gas chromatography-Electroantennography (GC-EAG) and coupled gas chromatography-mass spectrometry (GC-MS). Whilst GC-EAG on male moths showed an active peak, identified as 2-butyl (7Z)-dodecenoate, GC-MS also revealed the presence of the homologue 2-butyl (9Z)-tetradecenoate. Electroantennographic investigations, as well as field tests, strongly suggested the natural compounds to have the (R)-configuration at the stereogenic centre. Field results demonstrate 0.2 mg of a 1:1-mixture of (2R)-butyl (7Z)-dodecenoate and (2R)-butyl (9Z)-tetradecenoate to be a powerful lure that may be used in pest control measures against I. rotundata. The chemical structures of the new pheromone components show the same features as those of other zygaenid species: unsaturated fatty acids esterified with a short chain chiral alcohol. This is the first example of a two-component blend constituting the pheromone of a procridinid species.
-
identification of volatile compounds used in host location by the black bean aphid aphis fabae
Journal of Chemical Ecology, 2008Co-Authors: Ben Webster, Samuel Dufour, Claudia Birkemeyer, Jim Hardie, Michael Alexander Birkett, Toby J. A. Bruce, J. A. PickettAbstract:Behavioral and electrophysiological responses of winged Aphis fabae to volatiles of faba bean, Vicia faba (var. Sutton dwarf), plants were studied and semiochemicals used in host location were identified. In olfactometer bioassays, aphids spent significantly more time in the region of the olfactometer where V. faba volatiles from an intact plant were present than in control regions with clean air. This response also occurred when an air entrainment sample of a V. faba plant was used as the odor source. Coupled gas chromatography–Electroantennography revealed the presence of 16 electrophysiologically active compounds in the air entrainment sample. Fifteen of these were identified as (Z)-3-hexen-1-ol, 1-hexanol, (E)-2-hexenal, benzaldehyde, 6-methyl-5-hepten-2-one, octanal, (Z)-3-hexen-1-yl acetate, (R)-(−)-linalool, methyl salicylate, decanal, undecanal, (E)-caryophyllene, (E)-β-farnesene, (S)-(−)-germacrene D, and (E,E,)-4,8,12-trimethyl-1,3,7,11-tridecatetraene. An olfactometer response was observed to a 15-component synthetic blend that comprised all identified compounds at the same concentration and ratio as in the natural sample, with the aphids spending significantly more time in the treated regions of the olfactometer where volatiles were present than in the control regions. These data are discussed in the context of insect host location and crop protection.
-
electrophysiological and behavioural responses of the pollen beetle meligethes aeneus to volatiles from a non host plant lavender lavandula angustifolia lamiaceae
Arthropod-plant Interactions, 2008Co-Authors: Alice L. Mauchline, J. A. Pickett, Michael A. Birkett, C M Woodcock, Juliet L Osborne, W PowellAbstract:A semiochemical based push-pull strategy for control of oilseed rape pests is being developed at Rothamsted Research. This strategy uses insect and plant derived semiochemicals to manipulate pests and their natural enemies. An important element within this strategy is an understanding of the importance of non-host plant cues for pest insects and how such signals could be used to manipulate their behaviour. Previous studies using a range of non-host plants have shown that, for the pollen beetle Meligethes aeneus (Coleoptera: Nitidulidae), the essential oil of lavender, Lavandula angustifolia (Lamiaceae), was the most repellent. The aim of this study was to identify the active components in L. angustifolia oil, and to investigate the behaviour of M. aeneus to these chemicals, to establish the most effective use of repellent stimuli to disrupt colonisation of oilseed rape crops. Coupled gas chromatography-Electroantennography (GC-EAG) and gas chromatography-mass spectrometry (GC-MS) resulted in the identification of seven active compounds which were tested for behavioural activity using a 4-way olfactometer. Repellent responses were observed with (±)-linalool and (±)-linalyl acetate. The use of these chemicals within a push-pull pest control strategy is discussed.
Toby J. A. Bruce - One of the best experts on this subject based on the ideXlab platform.
-
electrophysiological and behavioral responses of female african rice gall midge orseolia oryzivora harris and gagne to host plant volatiles
Journal of Chemical Ecology, 2017Co-Authors: E. O. Ogah, John C. Caulfield, J. A. Pickett, Michael A. Birkett, C M Woodcock, F. E. Nwilene, L E Smart, Toby J. A. BruceAbstract:African rice gall midge, Orseolia oryzivora Harris and Gagne, is a major pest of rice in Africa. Depsite its economic importance, its chemical ecology is not well understood. Here, we assessed behavioral and electrophysiological responses of O. oryzivora to host plant volatiles. In olfactometer bioassays, mated female O. oryzivora were attracted to volatiles emitted from intact rice plants but were repelled by volatiles collected from plants infested by conspecifics. In a choice test, there was a preference for volatiles from uninfested plants over those from infested plants. Coupled gas chromatography-Electroantennography analyses of panicle volatiles isolated four electrophysiologically active components: (S)-linalool, 4,8-dimethyl-1,3,7-nonatriene, (E)-caryophyllene, and (R/S)-(E)-nerolidol. A synthetic blend of volatiles at the same concentration and ratio as that from an intact plant was attractive to mated females, whereas a blend based on the ratio of volatiles from an infested plant was repellent. This suggests that O. oryzivora uses olfaction for host plant recognition. The identification of blends of volatiles emitted by plants that can both attract and repel O. oryzivora may aid the development of sustainable control measures.
-
semiochemicals used in host location by the coffee berry borer hypothenemus hampei
Journal of Chemical Ecology, 2009Co-Authors: Esayas Mendesil, John C. Caulfield, Emiru Seyoum, Christine M. Woodcock, Toby J. A. Bruce, J. A. PickettAbstract:The coffee berry borer, Hypothenemus hampei is a serious pest in many coffee growing countries. Electrophysiological and behavioral responses of H. hampei to volatiles of different phenological stages of coffee, Coffea arabica, fruits were studied in order to identify volatile semiochemicals used in host location. Volatiles were collected from different phenological stages of C. arabica fruit by air entrainment. Electrophysiological recordings were made from insect antennae. Behavioral assays were carried out using a Perspex four-arm olfactometer. Insects spent significantly more time in the region of the olfactometer where ripe and dry fruit volatiles were present compared to control regions. Coupled gas chromatography—Electroantennography revealed the presence of six electrophysiologically active compounds in C. arabica volatiles. These were identified by using GC and GC-MS as methylcyclohexane, ethylbenzene, nonane, 1-octen-3-ol, (R)-limonene, and (R)-3-ethyl-4-methylpentanol. In the olfactometer bioassay, H. hampei showed a significant response to 3-ethyl-4-methylpentanol, methylcyclohexane, nonane, ethylbenzene, and a synthetic blend of these four compounds. Attraction to the synthetic blend was comparable to that for the natural sample. The significance of the study is discussed in terms of semiochemical based pest management methods of the coffee berry borer.
-
identification of volatile compounds used in host location by the black bean aphid aphis fabae
Journal of Chemical Ecology, 2008Co-Authors: Ben Webster, Samuel Dufour, Claudia Birkemeyer, Jim Hardie, Michael Alexander Birkett, Toby J. A. Bruce, J. A. PickettAbstract:Behavioral and electrophysiological responses of winged Aphis fabae to volatiles of faba bean, Vicia faba (var. Sutton dwarf), plants were studied and semiochemicals used in host location were identified. In olfactometer bioassays, aphids spent significantly more time in the region of the olfactometer where V. faba volatiles from an intact plant were present than in control regions with clean air. This response also occurred when an air entrainment sample of a V. faba plant was used as the odor source. Coupled gas chromatography–Electroantennography revealed the presence of 16 electrophysiologically active compounds in the air entrainment sample. Fifteen of these were identified as (Z)-3-hexen-1-ol, 1-hexanol, (E)-2-hexenal, benzaldehyde, 6-methyl-5-hepten-2-one, octanal, (Z)-3-hexen-1-yl acetate, (R)-(−)-linalool, methyl salicylate, decanal, undecanal, (E)-caryophyllene, (E)-β-farnesene, (S)-(−)-germacrene D, and (E,E,)-4,8,12-trimethyl-1,3,7,11-tridecatetraene. An olfactometer response was observed to a 15-component synthetic blend that comprised all identified compounds at the same concentration and ratio as in the natural sample, with the aphids spending significantly more time in the treated regions of the olfactometer where volatiles were present than in the control regions. These data are discussed in the context of insect host location and crop protection.
John A. Pickett - One of the best experts on this subject based on the ideXlab platform.
-
(2R,5S)‐Theaspirane Identified as the Kairomone for the Banana Weevil, Cosmopolites sordidus, from Attractive Senesced Leaves of the Host Banana, Musa spp.
Chemistry: A European Journal, 2018Co-Authors: Samson Abah Abagale, John C. Caulfield, Christine M. Woodcock, Antony M. Hooper, David M. Withall, Keith Chamberlain, Samuel Osafo Acquaah, Helmut F. Van Emden, Haruna Braimah, John A. PickettAbstract: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.
-
Conspecific and Heterogeneric Lacewings Respond to (Z)-4-Tridecene Identified from Chrysopa formosa (Neuroptera: Chrysopidae)
Journal of Chemical Ecology, 2018Co-Authors: Sandor Koczor, John C. Caulfield, Ferenc Szentkiralyi, David M. Withall, John A. Pickett, Michael A. Birkett, József Vuts, Miklos TothAbstract: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 (1 R ,4a S ,7 S ,7a R )-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.
-
Electrophysiological and behavioral responses of female African rice gall midge, Orseolia oryzivora Harris and Gagné, to host plant volatiles
Journal of Chemical Ecology, 2017Co-Authors: E. O. Ogah, John C. Caulfield, Christine M. Woodcock, John A. Pickett, Michael A. Birkett, F. E. Nwilene, L E Smart, Toby J. BruceAbstract:African rice gall midge, Orseolia oryzivora Harris and Gagné, is a major pest of rice in Africa. Depsite its economic importance, its chemical ecology is not well understood. Here, we assessed behavioral and electrophysiological responses of O. oryzivora to host plant volatiles. In olfactometer bioassays, mated female O. oryzivora were attracted to volatiles emitted from intact rice plants but were repelled by volatiles collected from plants infested by conspecifics. In a choice test, there was a preference for volatiles from uninfested plants over those from infested plants. Coupled gas chromatography-Electroantennography analyses of panicle volatiles isolated four electrophysiologically active components: ( S )-linalool, 4,8-dimethyl-1,3,7-nonatriene, ( E )-caryophyllene, and ( R/S )-( E )-nerolidol. A synthetic blend of volatiles at the same concentration and ratio as that from an intact plant was attractive to mated females, whereas a blend based on the ratio of volatiles from an infested plant was repellent. This suggests that O. oryzivora uses olfaction for host plant recognition. The identification of blends of volatiles emitted by plants that can both attract and repel O. oryzivora may aid the development of sustainable control measures.
Christine M. Woodcock - One of the best experts on this subject based on the ideXlab platform.
-
2r 5s theaspirane identified as the kairomone for the banana weevil cosmopolites sordidus from attractive senesced leaves of the host banana musa spp
Chemistry: A European Journal, 2018Co-Authors: John C. Caulfield, Christine M. Woodcock, Samson Abah Abagale, Antony M. Hooper, David M. Withall, Keith Chamberlain, Samuel Osafo Acquaah, Helmut F. Van Emden, Haruna BraimahAbstract: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.
-
(2R,5S)‐Theaspirane Identified as the Kairomone for the Banana Weevil, Cosmopolites sordidus, from Attractive Senesced Leaves of the Host Banana, Musa spp.
Chemistry: A European Journal, 2018Co-Authors: Samson Abah Abagale, John C. Caulfield, Christine M. Woodcock, Antony M. Hooper, David M. Withall, Keith Chamberlain, Samuel Osafo Acquaah, Helmut F. Van Emden, Haruna Braimah, John A. PickettAbstract: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.
-
Electrophysiological and behavioral responses of female African rice gall midge, Orseolia oryzivora Harris and Gagné, to host plant volatiles
Journal of Chemical Ecology, 2017Co-Authors: E. O. Ogah, John C. Caulfield, Christine M. Woodcock, John A. Pickett, Michael A. Birkett, F. E. Nwilene, L E Smart, Toby J. BruceAbstract:African rice gall midge, Orseolia oryzivora Harris and Gagné, is a major pest of rice in Africa. Depsite its economic importance, its chemical ecology is not well understood. Here, we assessed behavioral and electrophysiological responses of O. oryzivora to host plant volatiles. In olfactometer bioassays, mated female O. oryzivora were attracted to volatiles emitted from intact rice plants but were repelled by volatiles collected from plants infested by conspecifics. In a choice test, there was a preference for volatiles from uninfested plants over those from infested plants. Coupled gas chromatography-Electroantennography analyses of panicle volatiles isolated four electrophysiologically active components: ( S )-linalool, 4,8-dimethyl-1,3,7-nonatriene, ( E )-caryophyllene, and ( R/S )-( E )-nerolidol. A synthetic blend of volatiles at the same concentration and ratio as that from an intact plant was attractive to mated females, whereas a blend based on the ratio of volatiles from an infested plant was repellent. This suggests that O. oryzivora uses olfaction for host plant recognition. The identification of blends of volatiles emitted by plants that can both attract and repel O. oryzivora may aid the development of sustainable control measures.
-
semiochemicals used in host location by the coffee berry borer hypothenemus hampei
Journal of Chemical Ecology, 2009Co-Authors: Esayas Mendesil, John C. Caulfield, Emiru Seyoum, Christine M. Woodcock, Toby J. A. Bruce, J. A. PickettAbstract:The coffee berry borer, Hypothenemus hampei is a serious pest in many coffee growing countries. Electrophysiological and behavioral responses of H. hampei to volatiles of different phenological stages of coffee, Coffea arabica, fruits were studied in order to identify volatile semiochemicals used in host location. Volatiles were collected from different phenological stages of C. arabica fruit by air entrainment. Electrophysiological recordings were made from insect antennae. Behavioral assays were carried out using a Perspex four-arm olfactometer. Insects spent significantly more time in the region of the olfactometer where ripe and dry fruit volatiles were present compared to control regions. Coupled gas chromatography—Electroantennography revealed the presence of six electrophysiologically active compounds in C. arabica volatiles. These were identified by using GC and GC-MS as methylcyclohexane, ethylbenzene, nonane, 1-octen-3-ol, (R)-limonene, and (R)-3-ethyl-4-methylpentanol. In the olfactometer bioassay, H. hampei showed a significant response to 3-ethyl-4-methylpentanol, methylcyclohexane, nonane, ethylbenzene, and a synthetic blend of these four compounds. Attraction to the synthetic blend was comparable to that for the natural sample. The significance of the study is discussed in terms of semiochemical based pest management methods of the coffee berry borer.