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J A Pickett - One of the best experts on this subject based on the ideXlab platform.

  • activation of defence in sweet pepper capsicum annum by cis Jasmone and its impact on aphid and aphid parasitoid behaviour
    Pest Management Science, 2012
    Co-Authors: Sarah Y. Dewhirst, J L Martin, B J Pye, L E Smart, Michael A Birkett, Jim Hardie, E Lozareyes, J A Pickett
    Abstract:

    BACKGROUND: Two important pests of the sweet pepper, Capsicum annuum, are the peach potato aphid, Myzus persicae, and the glasshouse potato aphid, Aulacorthum solani. Current aphid control measures include the use of biological control agents, i.e. parasitic wasps, but with varying levels of success. One option to increase parasitoid efficiency is to activate plant defence. Therefore, sweet pepper plants were treated with the naturally occurring plant defence activator cis-Jasmone, and its impact upon the behaviour and development of aphids and aphid parasitoids was investigated. RESULTS: Growth rate studies revealed that the intrinsic rate of population increase of A. solani and M. persicae on sweet pepper plants treated with cis-Jasmone (cJSP) was not affected compared with untreated plants (UnSP), but the positive behavioural response of alate M. persicae towards the volatile organic compounds (VOCs) from UnSP was eliminated by cis-Jasmone treatment 48 h previously (cJSP48). In addition, the aphid parasitoid Aphidius ervi preferred VOCs from cJSP48 compared with UnSP, and a significant increase in foraging time was also observed on cJSP. Analysis of VOCs collected from cJSP48 revealed differences compared with UnSP. CONCLUSION: There is evidence that treatment with cis-Jasmone has the potential to improve protection of sweet pepper against insect pests. © Crown copyright 2012. Reproduced with permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.

  • attraction of the stink bug egg parasitoid telenomus podisi to defence signals from soybean activated by treatment with cis Jasmone
    Entomologia Experimentalis Et Applicata, 2009
    Co-Authors: Maria Carolina Blassioli Moraes, J A Pickett, Michael A Birkett, Raul Alberto Laumann, Martin Pareja, Fabiana Tavares Pires De Souza Sereno, M F F Michereff, Miguel Borges
    Abstract:

    After herbivore attack or chemical activation, plants release a blend of volatile organic compounds (VOCs) that is qualitatively or quantitatively different to the blend emitted by an undamaged plant. The altered blend of VOCs is then usually attractive to the herbivore's natural enemies. Soybean, Glycine max (L.) (Fabaceae), when damaged by stink bug herbivory, has been shown to emit a blend of VOCs that attracts the stink bug egg parasitoid Telenomus podisi (Ashmead) (Hymenoptera: Scelionidae) to the plant. In this study, our aim was to investigate changes in the VOC profile of soybean (var. BR16) elicited by the naturally occurring plant activator cis-Jasmone, and to determine whether these changes elicited the attraction of T. podisi. cis-Jasmone elicited chemical defence in soybean similar to that previously reported for stink bug damage. The main components induced by cis-Jasmone were camphene, myrcene, (E)-ocimene, methyl salicylate, and (E,E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene. In Y-tube behavioural bioassays, T. podisi preferred cis-Jasmone treated plants over untreated plants. Thus, cis-Jasmone appears to induce defence pathways in soybean similar to those induced by stink bug damage, and this phenomenon appears to be a promising tool for the manipulation of beneficial natural enemies in future sustainable stink bug control strategies. The delay in response demonstrates that cis-Jasmone treatment is not directly causing the response, but, more importantly, that it is causing activation of induced defence, long after initial treatment.

  • cis Jasmone treatment induces resistance in wheat plants against the grain aphid sitobion avenae fabricius homoptera aphididae
    Pest Management Science, 2003
    Co-Authors: Toby J A Bruce, J L Martin, J A Pickett, B J Pye, L E Smart, Lester J Wadhams
    Abstract:

    cis-Jasmone is a plant volatile known to have roles as an insect semiochemical and in inducing plant defence. It was evaluated in laboratory and field trials for control of cereal aphids. In an olfactometer bioassay cis-Jasmone was repellent to alatae of the grain aphid, Sitobion avenae (Fabricius) (Homoptera: Aphididae). Moreover, wheat, Triticum aestivum (L), seedlings sprayed with formulated cis-Jasmone 24 h previously were less susceptible to attack by S avenae than control plants. In field simulator studies, significantly fewer alate S avenae settled on cis-Jasmone-treated plants over a 24-h period. In addition, the intrinsic rate of population increase, rm, of S avenae apterae was reduced on cis-Jasmone treated seedlings. In a series of small-plot experiments conducted over four years, cis-Jasmone applications reduced cereal aphid populations infesting wheat in the field. Copyright © 2003 Society of Chemical Industry

  • new roles for cis Jasmone as an insect semiochemical and in plant defense
    Proceedings of the National Academy of Sciences of the United States of America, 2000
    Co-Authors: Michael A Birkett, Colin Campbell, Keith Chamberlain, Emilio Guerrieri, A J Hick, Janet L Martin, Michaela C Matthes, Johnathan A Napier, Jan Pettersson, J A Pickett
    Abstract:

    cis-Jasmone, or (Z)-Jasmone, is well known as a component of plant volatiles, and its release can be induced by damage, for example during insect herbivory. Using the olfactory system of the lettuce aphid to investigate volatiles from plants avoided by this insect, (Z)-Jasmone was found to be electrophysiologically active and also to be repellent in laboratory choice tests. In field studies, repellency from traps was demonstrated for the damson-hop aphid, and with cereal aphids numbers were reduced in plots of winter wheat treated with (Z)-Jasmone. In contrast, attractant activity was found in laboratory and wind tunnel tests for insects acting antagonistically to aphids, namely the seven-spot ladybird and an aphid parasitoid. When applied in the vapor phase to intact bean plants, (Z)-Jasmone induced the production of volatile compounds, including the monoterpene (E)-β-ocimene, which affect plant defense, for example by stimulating the activity of parasitic insects. These plants were more attractive to the aphid parasitoid in the wind tunnel when tested 48 h after exposure to (Z)-Jasmone had ceased. This possible signaling role of (Z)-Jasmone is qualitatively different from that of the biosynthetically related methyl jasmonate and gives a long-lasting effect after removal of the stimulus. Differential display was used to compare mRNA populations in bean leaves exposed to the vapor of (Z)-Jasmone and methyl jasmonate. One differentially displayed fragment was cloned and shown by Northern blotting to be up-regulated in leaf tissue by (Z)-Jasmone. This sequence was identified by homology as being derived from a gene encoding an α-tubulin isoform.

Michael A Birkett - One of the best experts on this subject based on the ideXlab platform.

  • activation of defence in sweet pepper capsicum annum by cis Jasmone and its impact on aphid and aphid parasitoid behaviour
    Pest Management Science, 2012
    Co-Authors: Sarah Y. Dewhirst, J L Martin, B J Pye, L E Smart, Michael A Birkett, Jim Hardie, E Lozareyes, J A Pickett
    Abstract:

    BACKGROUND: Two important pests of the sweet pepper, Capsicum annuum, are the peach potato aphid, Myzus persicae, and the glasshouse potato aphid, Aulacorthum solani. Current aphid control measures include the use of biological control agents, i.e. parasitic wasps, but with varying levels of success. One option to increase parasitoid efficiency is to activate plant defence. Therefore, sweet pepper plants were treated with the naturally occurring plant defence activator cis-Jasmone, and its impact upon the behaviour and development of aphids and aphid parasitoids was investigated. RESULTS: Growth rate studies revealed that the intrinsic rate of population increase of A. solani and M. persicae on sweet pepper plants treated with cis-Jasmone (cJSP) was not affected compared with untreated plants (UnSP), but the positive behavioural response of alate M. persicae towards the volatile organic compounds (VOCs) from UnSP was eliminated by cis-Jasmone treatment 48 h previously (cJSP48). In addition, the aphid parasitoid Aphidius ervi preferred VOCs from cJSP48 compared with UnSP, and a significant increase in foraging time was also observed on cJSP. Analysis of VOCs collected from cJSP48 revealed differences compared with UnSP. CONCLUSION: There is evidence that treatment with cis-Jasmone has the potential to improve protection of sweet pepper against insect pests. © Crown copyright 2012. Reproduced with permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.

  • Activation of defence in sweet pepper, Capsicum annum, by cis‐Jasmone, and its impact on aphid and aphid parasitoid behaviour
    Pest management science, 2012
    Co-Authors: Sarah Y. Dewhirst, J L Martin, Michael A Birkett, Lesley E. Smart, Barry J. Pye, Jim Hardie, E. Loza-reyes, John A. Pickett
    Abstract:

    BACKGROUND: Two important pests of the sweet pepper, Capsicum annuum, are the peach potato aphid, Myzus persicae, and the glasshouse potato aphid, Aulacorthum solani. Current aphid control measures include the use of biological control agents, i.e. parasitic wasps, but with varying levels of success. One option to increase parasitoid efficiency is to activate plant defence. Therefore, sweet pepper plants were treated with the naturally occurring plant defence activator cis-Jasmone, and its impact upon the behaviour and development of aphids and aphid parasitoids was investigated. RESULTS: Growth rate studies revealed that the intrinsic rate of population increase of A. solani and M. persicae on sweet pepper plants treated with cis-Jasmone (cJSP) was not affected compared with untreated plants (UnSP), but the positive behavioural response of alate M. persicae towards the volatile organic compounds (VOCs) from UnSP was eliminated by cis-Jasmone treatment 48 h previously (cJSP48). In addition, the aphid parasitoid Aphidius ervi preferred VOCs from cJSP48 compared with UnSP, and a significant increase in foraging time was also observed on cJSP. Analysis of VOCs collected from cJSP48 revealed differences compared with UnSP. CONCLUSION: There is evidence that treatment with cis-Jasmone has the potential to improve protection of sweet pepper against insect pests. © Crown copyright 2012. Reproduced with permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.

  • Changes in concentration of isoflavonoids after cis-Jasmone spraying in the leaves of two soybean cultivars.
    2010
    Co-Authors: J. P. Da Graça, Michael A Birkett, Tiago Kijoshi Ueda, Tatiani Janegitz, D. M. Da Silva, J. M. Maeda, Maria Carolina Blassioli Moraes, John A. Pickett, A. De F. Bueno, Clara Beatriz Hoffmann-campo
    Abstract:

    cis-Jasmone is a naturally-occurring compound in plants that activates direct and indirect defence in model and crop plants'". Exogenous application of cis-Jasmone increases flavonoid concentrations in soybean and affects negatively Anticarsia gemmatalis weight gain. Here, foliar isoflavonoid concentrations were evaluated after cis-Jasmone spraying on soybean cultivars BRS l34 and lAC 100, grown at Embrapa Soybean greenhouse facilities. At V) development stage, plants were sprayed with water, Tween 20 + water or cis-Jasmone + tween 20 + water. For flavonoid extraction, leaves were collected 12, 24, 48, 96, and 120h after spraying, and immediately frozen in liquid nitrogen, ground in a mortar and extracted in MeOH 90% or EtOH 80% + HCI (0.001 M). Isoflavonoid concentrations were estimated by HPLC analysis. The extracts obtained from leaves of both genotypes of 24 h cis-Jasmone treated plants presented higher quantities of daidzin, malonyl-daidzin, glycitin, malonyl-glycitin, glycitein and genistin, when compared to water and Tween 20 + water treated plants. Daidzein was present in high concentration, in both cultivars, 24 h and 48 h after cis-Jasmone spraying, but no longer detected in samples collected 120 h after treatment. Coumesterol was detected, but only from samples collected 48 h after spraying. It is possible that such increases may be related to the decrease in daidzein concentration, considering that this compound is involved in coumesterol synthesis. Comparing solvent efficiencies, EtOH 80% + HCI (0.001 M) presented higher extraction capacity than MeOH 90%; coumestrol concentration in ethanolic extracts was approximately twice as high as in methanolic extracts. Our results indicated that cis-Jasmone induces the production of non-volatile compounds in soybean such as isoflavonoids, and that EtOH 80% + HCI (O.OOIM)extraction is more efficient when compared to MeOH 90%.

  • attraction of the stink bug egg parasitoid telenomus podisi to defence signals from soybean activated by treatment with cis Jasmone
    Entomologia Experimentalis Et Applicata, 2009
    Co-Authors: Maria Carolina Blassioli Moraes, J A Pickett, Michael A Birkett, Raul Alberto Laumann, Martin Pareja, Fabiana Tavares Pires De Souza Sereno, M F F Michereff, Miguel Borges
    Abstract:

    After herbivore attack or chemical activation, plants release a blend of volatile organic compounds (VOCs) that is qualitatively or quantitatively different to the blend emitted by an undamaged plant. The altered blend of VOCs is then usually attractive to the herbivore's natural enemies. Soybean, Glycine max (L.) (Fabaceae), when damaged by stink bug herbivory, has been shown to emit a blend of VOCs that attracts the stink bug egg parasitoid Telenomus podisi (Ashmead) (Hymenoptera: Scelionidae) to the plant. In this study, our aim was to investigate changes in the VOC profile of soybean (var. BR16) elicited by the naturally occurring plant activator cis-Jasmone, and to determine whether these changes elicited the attraction of T. podisi. cis-Jasmone elicited chemical defence in soybean similar to that previously reported for stink bug damage. The main components induced by cis-Jasmone were camphene, myrcene, (E)-ocimene, methyl salicylate, and (E,E)-4,8,12-trimethyltrideca-1,3,7,11-tetraene. In Y-tube behavioural bioassays, T. podisi preferred cis-Jasmone treated plants over untreated plants. Thus, cis-Jasmone appears to induce defence pathways in soybean similar to those induced by stink bug damage, and this phenomenon appears to be a promising tool for the manipulation of beneficial natural enemies in future sustainable stink bug control strategies. The delay in response demonstrates that cis-Jasmone treatment is not directly causing the response, but, more importantly, that it is causing activation of induced defence, long after initial treatment.

  • cis-Jasmone induces accumulation of defence compounds in wheat, Triticum aestivum
    Phytochemistry, 2007
    Co-Authors: Maria Carolina Blassioli Moraes, J L Martin, Michael A Birkett, Ruth Gordon-weeks, Lesley E. Smart, Barry J. Pye, Richard H. Bromilow, John A. Pickett
    Abstract:

    Liquid phase extraction (LPE) and vapor phase extraction (VPE) methodologies were used to evaluate the impact of the plant activator, cis-Jasmone, on the secondary metabolism of wheat, Triticum aestivum, var. Solstice. LPE allowed the measurement of benzoxazinoids, i.e. 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA), 2-hydroxy-7-methoxy-1,4-benzoxazin-3-one (HMBOA) and 6-methoxy-benzoxazolin-2-one (MBOA), and phenolic acids such as trans-p-coumaric acid, syringic acid, p-hydroxybenzoic acid, vanillic acid and cis- and trans-ferulic acid. Using LPE, a significantly higher level of DIMBOA was found in aerial parts and roots of T. aestivum following treatment with cis-Jasmone, when compared with untreated plants. Similar results were obtained for phenolic acids, such as trans-ferulic acid and vanillic acid in roots. Using VPE, it was possible to measure levels of 2-hydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one (HBOA), benzoxazolin-2(3H)-one (BOA), ferulic acid, syringic acid and coumaric acid. The levels of HBOA in aerial parts and roots were significantly greater in cis-Jasmone treated plants compared to untreated plants. cis-Jasmone is known to be a plant activator in terms of production of defence-related volatile semiochemicals that repel aphids and increase the foraging activity of aphid parasitoids. These results show, for the first time, that cis-Jasmone also induces selective production of secondary metabolites that are capable of directly reducing development of pests, diseases and weeds.

John A. Pickett - One of the best experts on this subject based on the ideXlab platform.

  • Activation of defence in sweet pepper, Capsicum annum, by cis‐Jasmone, and its impact on aphid and aphid parasitoid behaviour
    Pest management science, 2012
    Co-Authors: Sarah Y. Dewhirst, J L Martin, Michael A Birkett, Lesley E. Smart, Barry J. Pye, Jim Hardie, E. Loza-reyes, John A. Pickett
    Abstract:

    BACKGROUND: Two important pests of the sweet pepper, Capsicum annuum, are the peach potato aphid, Myzus persicae, and the glasshouse potato aphid, Aulacorthum solani. Current aphid control measures include the use of biological control agents, i.e. parasitic wasps, but with varying levels of success. One option to increase parasitoid efficiency is to activate plant defence. Therefore, sweet pepper plants were treated with the naturally occurring plant defence activator cis-Jasmone, and its impact upon the behaviour and development of aphids and aphid parasitoids was investigated. RESULTS: Growth rate studies revealed that the intrinsic rate of population increase of A. solani and M. persicae on sweet pepper plants treated with cis-Jasmone (cJSP) was not affected compared with untreated plants (UnSP), but the positive behavioural response of alate M. persicae towards the volatile organic compounds (VOCs) from UnSP was eliminated by cis-Jasmone treatment 48 h previously (cJSP48). In addition, the aphid parasitoid Aphidius ervi preferred VOCs from cJSP48 compared with UnSP, and a significant increase in foraging time was also observed on cJSP. Analysis of VOCs collected from cJSP48 revealed differences compared with UnSP. CONCLUSION: There is evidence that treatment with cis-Jasmone has the potential to improve protection of sweet pepper against insect pests. © Crown copyright 2012. Reproduced with permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.

  • Emerging roles in plant defense for cis-Jasmone-induced cytochrome P450 CYP81D11
    Plant signaling & behavior, 2011
    Co-Authors: Michaela C Matthes, Toby J A Bruce, Keith Chamberlain, John A. Pickett, Johnathan A Napier
    Abstract:

    cis-Jasmone is a volatile organic compound emitted constitutively by flowers or leaves of several plant species where it acts as an attractant for pollinators and as a chemical cue for host localisation (or avoidance) for insects. ( 1-3) It is also released by some plant species after feeding damage inflicted by herbivorous insects and in this case might serve as a chemical cue for parasitoids to guide them to their prey (so called "indirect defense"). ( 4,5) Moreover, we have recently shown that plants can perceive cis-Jasmone and that it acts as a signaling molecule in A. thaliana, inducing a discrete and distinctive suite of genes, of which a large subset is putatively involved in metabolism and defense responses. ( 6) Cytochrome P450s feature prominently in these functional subsets and of these the highest fold change upon cis-Jasmone treatment occurred with the cytochrome CYP81D11 (At3g28740). ( 6) Hence this gene was chosen for a more thorough analysis of the potential biological relevance of the cis-Jasmone induced defense response. Although the precise function of CYP81D11 remains to be determined, we could previously demonstrate its involvement in the indirect defense response in Arabidopsis, as plants exposed to cis-Jasmone ceased to be attractive to the aphid parasitoid Aphidius ervi when this P450 was inactivated by T-DNA insertion mutagenesis. ( 6) Here we report additional experiments which give further support to a role of CYP81D11 in the direct or indirect defense response of A. thaliana.

  • Changes in concentration of isoflavonoids after cis-Jasmone spraying in the leaves of two soybean cultivars.
    2010
    Co-Authors: J. P. Da Graça, Michael A Birkett, Tiago Kijoshi Ueda, Tatiani Janegitz, D. M. Da Silva, J. M. Maeda, Maria Carolina Blassioli Moraes, John A. Pickett, A. De F. Bueno, Clara Beatriz Hoffmann-campo
    Abstract:

    cis-Jasmone is a naturally-occurring compound in plants that activates direct and indirect defence in model and crop plants'". Exogenous application of cis-Jasmone increases flavonoid concentrations in soybean and affects negatively Anticarsia gemmatalis weight gain. Here, foliar isoflavonoid concentrations were evaluated after cis-Jasmone spraying on soybean cultivars BRS l34 and lAC 100, grown at Embrapa Soybean greenhouse facilities. At V) development stage, plants were sprayed with water, Tween 20 + water or cis-Jasmone + tween 20 + water. For flavonoid extraction, leaves were collected 12, 24, 48, 96, and 120h after spraying, and immediately frozen in liquid nitrogen, ground in a mortar and extracted in MeOH 90% or EtOH 80% + HCI (0.001 M). Isoflavonoid concentrations were estimated by HPLC analysis. The extracts obtained from leaves of both genotypes of 24 h cis-Jasmone treated plants presented higher quantities of daidzin, malonyl-daidzin, glycitin, malonyl-glycitin, glycitein and genistin, when compared to water and Tween 20 + water treated plants. Daidzein was present in high concentration, in both cultivars, 24 h and 48 h after cis-Jasmone spraying, but no longer detected in samples collected 120 h after treatment. Coumesterol was detected, but only from samples collected 48 h after spraying. It is possible that such increases may be related to the decrease in daidzein concentration, considering that this compound is involved in coumesterol synthesis. Comparing solvent efficiencies, EtOH 80% + HCI (0.001 M) presented higher extraction capacity than MeOH 90%; coumestrol concentration in ethanolic extracts was approximately twice as high as in methanolic extracts. Our results indicated that cis-Jasmone induces the production of non-volatile compounds in soybean such as isoflavonoids, and that EtOH 80% + HCI (O.OOIM)extraction is more efficient when compared to MeOH 90%.

  • cis-Jasmone induces accumulation of defence compounds in wheat, Triticum aestivum
    Phytochemistry, 2007
    Co-Authors: Maria Carolina Blassioli Moraes, J L Martin, Michael A Birkett, Ruth Gordon-weeks, Lesley E. Smart, Barry J. Pye, Richard H. Bromilow, John A. Pickett
    Abstract:

    Liquid phase extraction (LPE) and vapor phase extraction (VPE) methodologies were used to evaluate the impact of the plant activator, cis-Jasmone, on the secondary metabolism of wheat, Triticum aestivum, var. Solstice. LPE allowed the measurement of benzoxazinoids, i.e. 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA), 2-hydroxy-7-methoxy-1,4-benzoxazin-3-one (HMBOA) and 6-methoxy-benzoxazolin-2-one (MBOA), and phenolic acids such as trans-p-coumaric acid, syringic acid, p-hydroxybenzoic acid, vanillic acid and cis- and trans-ferulic acid. Using LPE, a significantly higher level of DIMBOA was found in aerial parts and roots of T. aestivum following treatment with cis-Jasmone, when compared with untreated plants. Similar results were obtained for phenolic acids, such as trans-ferulic acid and vanillic acid in roots. Using VPE, it was possible to measure levels of 2-hydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one (HBOA), benzoxazolin-2(3H)-one (BOA), ferulic acid, syringic acid and coumaric acid. The levels of HBOA in aerial parts and roots were significantly greater in cis-Jasmone treated plants compared to untreated plants. cis-Jasmone is known to be a plant activator in terms of production of defence-related volatile semiochemicals that repel aphids and increase the foraging activity of aphid parasitoids. These results show, for the first time, that cis-Jasmone also induces selective production of secondary metabolites that are capable of directly reducing development of pests, diseases and weeds.

  • cis -Jasmone as allelopathic agent in inducing plant defence
    2007
    Co-Authors: John A. Pickett, Toby J A Bruce, Michael A Birkett, Keith Chamberlain, Michaela C Matthes, Johnathan A Napier, Ruth Gordon-weeks, Lesley E. Smart, M. C. Blassioli Moraes, Lester J Wadhams
    Abstract:

    The study of plant/insect interactions, particularly in multitrophic systems, it is possible to identify the insect semiochemicals that may induce defence responses in plants. From such work, cis-Jasmone was identified as having highly specific and persistent effects in regulating the expression of genes associated with plant defence. The molecular genetic mechanisms involved are being investigated in Arabiclopsis thaliana by microan-ay analyses, the use of knockout lines and by functional gene expression studies in A. thallana and other systems. In cereals, there are major varietal differences in the level of defence induced by cis¬-Jasmone. With some elite cultivars, long term protection against aphids has been established in the field. Chemical studies and investigations with insects using electrophysiological and behavioural assays have shown that 6-methy1-5-hepten-2-one, the production of which is induced by cis-Jasmone, is highly active in reducing aphid colonisation and increasing foraging by parasitoids. Differential induction between cultivars may provide a useful means to elucidate the associated genetics. In both wheat and barley, there is additionally an induction with cis-Jasmone of antibiotic effects against aphids. In wheat, this appears to be due to enhanced production of hydroxamic acids. For these secondary metabolites, the associated genes are known and RT-PCR is used to determine the induction of expression. MS", after derivatisation and chromatography, provides analytical tool to estimate these and unknown antibiotic agents in barley.

Johnathan A Napier - One of the best experts on this subject based on the ideXlab platform.

  • Emerging roles in plant defense for cis-Jasmone-induced cytochrome P450 CYP81D11
    Plant signaling & behavior, 2011
    Co-Authors: Michaela C Matthes, Toby J A Bruce, Keith Chamberlain, John A. Pickett, Johnathan A Napier
    Abstract:

    cis-Jasmone is a volatile organic compound emitted constitutively by flowers or leaves of several plant species where it acts as an attractant for pollinators and as a chemical cue for host localisation (or avoidance) for insects. ( 1-3) It is also released by some plant species after feeding damage inflicted by herbivorous insects and in this case might serve as a chemical cue for parasitoids to guide them to their prey (so called "indirect defense"). ( 4,5) Moreover, we have recently shown that plants can perceive cis-Jasmone and that it acts as a signaling molecule in A. thaliana, inducing a discrete and distinctive suite of genes, of which a large subset is putatively involved in metabolism and defense responses. ( 6) Cytochrome P450s feature prominently in these functional subsets and of these the highest fold change upon cis-Jasmone treatment occurred with the cytochrome CYP81D11 (At3g28740). ( 6) Hence this gene was chosen for a more thorough analysis of the potential biological relevance of the cis-Jasmone induced defense response. Although the precise function of CYP81D11 remains to be determined, we could previously demonstrate its involvement in the indirect defense response in Arabidopsis, as plants exposed to cis-Jasmone ceased to be attractive to the aphid parasitoid Aphidius ervi when this P450 was inactivated by T-DNA insertion mutagenesis. ( 6) Here we report additional experiments which give further support to a role of CYP81D11 in the direct or indirect defense response of A. thaliana.

  • cis -Jasmone as allelopathic agent in inducing plant defence
    2007
    Co-Authors: John A. Pickett, Toby J A Bruce, Michael A Birkett, Keith Chamberlain, Michaela C Matthes, Johnathan A Napier, Ruth Gordon-weeks, Lesley E. Smart, M. C. Blassioli Moraes, Lester J Wadhams
    Abstract:

    The study of plant/insect interactions, particularly in multitrophic systems, it is possible to identify the insect semiochemicals that may induce defence responses in plants. From such work, cis-Jasmone was identified as having highly specific and persistent effects in regulating the expression of genes associated with plant defence. The molecular genetic mechanisms involved are being investigated in Arabiclopsis thaliana by microan-ay analyses, the use of knockout lines and by functional gene expression studies in A. thallana and other systems. In cereals, there are major varietal differences in the level of defence induced by cis¬-Jasmone. With some elite cultivars, long term protection against aphids has been established in the field. Chemical studies and investigations with insects using electrophysiological and behavioural assays have shown that 6-methy1-5-hepten-2-one, the production of which is induced by cis-Jasmone, is highly active in reducing aphid colonisation and increasing foraging by parasitoids. Differential induction between cultivars may provide a useful means to elucidate the associated genetics. In both wheat and barley, there is additionally an induction with cis-Jasmone of antibiotic effects against aphids. In wheat, this appears to be due to enhanced production of hydroxamic acids. For these secondary metabolites, the associated genes are known and RT-PCR is used to determine the induction of expression. MS", after derivatisation and chromatography, provides analytical tool to estimate these and unknown antibiotic agents in barley.

  • new roles for cis Jasmone as an insect semiochemical and in plant defense
    Proceedings of the National Academy of Sciences of the United States of America, 2000
    Co-Authors: Michael A Birkett, Colin Campbell, Keith Chamberlain, Emilio Guerrieri, A J Hick, Janet L Martin, Michaela C Matthes, Johnathan A Napier, Jan Pettersson, J A Pickett
    Abstract:

    cis-Jasmone, or (Z)-Jasmone, is well known as a component of plant volatiles, and its release can be induced by damage, for example during insect herbivory. Using the olfactory system of the lettuce aphid to investigate volatiles from plants avoided by this insect, (Z)-Jasmone was found to be electrophysiologically active and also to be repellent in laboratory choice tests. In field studies, repellency from traps was demonstrated for the damson-hop aphid, and with cereal aphids numbers were reduced in plots of winter wheat treated with (Z)-Jasmone. In contrast, attractant activity was found in laboratory and wind tunnel tests for insects acting antagonistically to aphids, namely the seven-spot ladybird and an aphid parasitoid. When applied in the vapor phase to intact bean plants, (Z)-Jasmone induced the production of volatile compounds, including the monoterpene (E)-β-ocimene, which affect plant defense, for example by stimulating the activity of parasitic insects. These plants were more attractive to the aphid parasitoid in the wind tunnel when tested 48 h after exposure to (Z)-Jasmone had ceased. This possible signaling role of (Z)-Jasmone is qualitatively different from that of the biosynthetically related methyl jasmonate and gives a long-lasting effect after removal of the stimulus. Differential display was used to compare mRNA populations in bean leaves exposed to the vapor of (Z)-Jasmone and methyl jasmonate. One differentially displayed fragment was cloned and shown by Northern blotting to be up-regulated in leaf tissue by (Z)-Jasmone. This sequence was identified by homology as being derived from a gene encoding an α-tubulin isoform.

Lester J Wadhams - One of the best experts on this subject based on the ideXlab platform.

  • Treating hop plants with (Z)-Jasmone increases colonization by Phorodon humuli (Hemiptera: Aphididae) spring migrants
    Bulletin of entomological research, 2007
    Co-Authors: Tom W. Pope, Colin A. M. Campbell, Jim Hardie, Lester J Wadhams
    Abstract:

    Hop plants were sprayed with (Z)-Jasmone, at a rate of 50 g ha(-1), during the spring migration of the damson-hop aphid Phorodon humuli (Schrank) in 2002 and 2003. Numbers of P. humuli spring migrants colonizing hop plants, Humulus lupulus L., 2-6 and 7-11 days after applying this treatment were assessed in both years. During the first five-day period, significantly more spring migrants were found on hop plants treated with (Z)-Jasmone, in comparison with control plants, in 2002. By contrast, no significant difference was evident in the second five-day period. Although the migration in 2003 was much lighter than in 2002, greater numbers of migrants were again removed from treated plants. Indeed, more spring migrants were removed from plants sprayed with (Z)-Jasmone in this year during both five-day periods (11 and 44%, respectively) compared with the 23% greater numbers removed in the first five-day period in 2002. Therefore, unlike some other species of aphid, where numbers were consistently lower on plots sprayed with (Z)-Jasmone, spraying the secondary host of P. humuli with this compound appears to increase colonization by spring migrants.

  • cis -Jasmone as allelopathic agent in inducing plant defence
    2007
    Co-Authors: John A. Pickett, Toby J A Bruce, Michael A Birkett, Keith Chamberlain, Michaela C Matthes, Johnathan A Napier, Ruth Gordon-weeks, Lesley E. Smart, M. C. Blassioli Moraes, Lester J Wadhams
    Abstract:

    The study of plant/insect interactions, particularly in multitrophic systems, it is possible to identify the insect semiochemicals that may induce defence responses in plants. From such work, cis-Jasmone was identified as having highly specific and persistent effects in regulating the expression of genes associated with plant defence. The molecular genetic mechanisms involved are being investigated in Arabiclopsis thaliana by microan-ay analyses, the use of knockout lines and by functional gene expression studies in A. thallana and other systems. In cereals, there are major varietal differences in the level of defence induced by cis¬-Jasmone. With some elite cultivars, long term protection against aphids has been established in the field. Chemical studies and investigations with insects using electrophysiological and behavioural assays have shown that 6-methy1-5-hepten-2-one, the production of which is induced by cis-Jasmone, is highly active in reducing aphid colonisation and increasing foraging by parasitoids. Differential induction between cultivars may provide a useful means to elucidate the associated genetics. In both wheat and barley, there is additionally an induction with cis-Jasmone of antibiotic effects against aphids. In wheat, this appears to be due to enhanced production of hydroxamic acids. For these secondary metabolites, the associated genes are known and RT-PCR is used to determine the induction of expression. MS", after derivatisation and chromatography, provides analytical tool to estimate these and unknown antibiotic agents in barley.

  • cis Jasmone treatment induces resistance in wheat plants against the grain aphid sitobion avenae fabricius homoptera aphididae
    Pest Management Science, 2003
    Co-Authors: Toby J A Bruce, J L Martin, J A Pickett, B J Pye, L E Smart, Lester J Wadhams
    Abstract:

    cis-Jasmone is a plant volatile known to have roles as an insect semiochemical and in inducing plant defence. It was evaluated in laboratory and field trials for control of cereal aphids. In an olfactometer bioassay cis-Jasmone was repellent to alatae of the grain aphid, Sitobion avenae (Fabricius) (Homoptera: Aphididae). Moreover, wheat, Triticum aestivum (L), seedlings sprayed with formulated cis-Jasmone 24 h previously were less susceptible to attack by S avenae than control plants. In field simulator studies, significantly fewer alate S avenae settled on cis-Jasmone-treated plants over a 24-h period. In addition, the intrinsic rate of population increase, rm, of S avenae apterae was reduced on cis-Jasmone treated seedlings. In a series of small-plot experiments conducted over four years, cis-Jasmone applications reduced cereal aphid populations infesting wheat in the field. Copyright © 2003 Society of Chemical Industry