Volatiles induced

Plants respond to the mechanical or insect herbivore damage of their tissues." During herbivorous attacks, some plants emit a specific blend of volatiles, which may result in defense responses retarding development of the herbivores or attraction of herbivore enemies to feed upon them. In lima bean leaves, the spider mite-induced volatiles, as well as infestation and artificial wounding, activate the ethylene and JA signaling pathways. ... 

Mercke P, Kappers IF, Verstappen FWA, Vorst O, Dicke M, Bouwmeester HJ (2004) Combined transcript and metabohte analysis reveals genes involved in spider mite induced volatile formation in cucumber plants. Plant Physiol 135 2012-2024... 

Cheng AX, Xiang CY, Li JX, Yang CQ, Hu WL, Wang LJ, Lou YG, Chen XY (2007) The rice ( )-beta-caryophyUene synthase (OsTPS3) accounts for the major inducible volatile sesquiterpenes. Phytochemistry 68 1632-1641... 

Hopke J, Donath J, Blechert S, Boland W (1994) Herbivore-induced volatiles - the emission of acyclic homoterpenes from leaves of Phaseolus lunatus and Zea mays can be triggered by a a-glucosidase and jasmonic acid. FEBS Lett 352 146-150... 

Arimura G-i, Ozawa R, Shimoda T, Nishioka T, Boland W, Takabayashi J (2000) Herbivory-induced volatiles elicit defence genes in lima bean leaves. Nature 406 512-515... 

Ealdt J, Arimura G, Gershenzon J, Takabayashi J, Bohlmann J (2003) Functional identification of AtTPSOS as ( )-P-ocimene synthase a monoterpene synthase catalyzing jasmonate- and wound-induced volatile formation in Arabidopsis thaliana. Planta 216 745-751... 

Van Poecke RMP, Posthumus MA, Dicke M (2001) Herbivore-induced volatile production by Arabidopsis thaliana leads to attraction of the parasitoid Cotesia rubecula Chemical, behavioral, and gene-expression analysis. J Chem Ecol 27 1911-1928... 

This chapter gives an overview of the developments in research on induced indirect defenses. We discuss both the ecological aspects as well as our knowledge of the mechanisms that are involved. This chapter differs from most other reviews in that it includes both attraction by means of induced volatiles and the plant s... 

Arimura et al. (2000a) found that several of the induced volatiles themselves can serve as elicitors by triggering gene activation in neighboring leaves that leads to further emissions. In this context, (Z)-jasmone was shown to be a potent plant-derived volatile elicitor that triggers the release of -ocimene in the bean plant, Viciafaba (Birkett et al, 2000). These examples of plant odors inducing plant defense pathways have important implications for plant-plant communication (see below). 

As yet, there is no specific pattern in how induced volatiles affect the attractiveness of plants to herbivores. Obviously, the responses will be correlated with fitness consequences. Insects vulnerable to natural enemies and induced plant toxins are, therefore, expected to avoid induced plants, whereas those that are adapted to plant defenses and/or benefit from aggregating are likely to be attracted. Comparative studies could test such hypotheses. 

In the spider mite-lima bean system, it has now been shown that mite infestation activates defense genes in the plants and, in addition, several of these genes can also be activated when a Uma bean plant is exposed to some of the induced volatiles of neighboring conspecihcs (Arimura et al., 2000a,b). Clearly, the genetic basis for plant-plant communication is in place. That it can actually take place in the held has now also been confirmed. 

In the context of tritrophic interactions, plant-plant communication has been subject to only few studies (Bruin et al., 1995). In one such study, Bruin et al. (1992) demonstrated that healthy cotton plants that were exposed to spider mite-induced volatiles from conspecihc plants increased in their attractiveness to predatory mites. This increased attraction was probably not simply the result of adsorbence and re-release of these volatiles from the healthy plants, because there is now clear evidence that volatiles from spider mite-infested plants can induce odor releases in neighboring plants (Arimura et al, 2000a). 

This rather unspecific induction of nectar secretion in cotton was surprising in light of the fact that the induction of volatile emission by this plant had been demonstrated to be specific. Herbivore-damaged plants show a higher rate of volatile emission compared with mechanically damaged plants (McCall et al, 1994), and herbivore feeding induced de novo synthesis of various terpenoids (Pare and Tumlinson, 1997), which resulted in a quantitative as well as a qualitative response to herbivory. The specificity of the plant response is not restricted to the differentiation between mechanical damage and herbivory. The composition of the induced volatile blend also varies between (even closely related) herbivore species (De Moraes etal, 1998). 

The sophisticated equipment required for volatile identification has long confined the topic of herbivore-induced volatiles to the laboratory, but extrafloral nectaries have traditionally been studied in the field. Moreover, the work on extrafloral nectaries has mainly addressed wild plant species within their natural habitat, whereas the study of plant volatiles has long focussed on agricultural crops. As a result, we have a relative wealth of held evidence for the defensive function of extrafloral nectaries. 

Arimura, G., Tashiro, K., Kuhara, S Nishioka, T., Ozawa, R. and Takabayashi, J. (2000b). Gene responses in bean leaves induced by herbivory and by herbivore-induced volatiles. Biochemical and Biophysical Research Communications 277 ... 

Bernasconi Ockroy, M. L., Turlings, T. J. C., Edwards, P. J. et al. (2001). Response of natural populations of predators and parasitoids to artificially induced volatile emissions in maize plants (Zea mays L.). Agricultural and Forest Entomology 3 ... 

Gouingucne, S. (2000). Specificity and variability in induced volatile signalling in maize plants, University of Neuchatel, Switzerland. 

Gouingucne, S. and Turlings, T. C. J. (2002). The effects of abiotic factors on induced volatile emissions in com plants. Plant Physiology 129 1296-1307. 

Comparison of cultivars of ornamental crop Gerbera jamesonii on production of spider mite-induced volatiles, and their attractiveness to the predator Phytoseiulus persimilis. Journal of Chemical Ecology 27 1355-1372. 

Loughrin, J. H Manukian, A., Heath, R. R Turlings, T. C. J. and Tumlinson, J. H. (1994). Diurnal cycle of emission of induced volatile terpenoids herbivore-injured cotton plants. Proceedings of the National Academy of Sciences, USA 91 11836-11840. 

Ozawa, R., Arimura, G., Takabayashi, J., Shimoda, T. and Nishioka, T. (2000). Involvement of jasmonate- and salicylate-related signaling pathways for the production of specific herbivore-induced volatiles in plants. Plant and Cell Physiology 41 391-398. 

Rodriguez-Saona, C., Crafts-Brander, S. J., Pare, P. W. and Henneberry, T. J. (2001). Exogenous methyl jasmonate induces volatile emissions in cotton plants. Journal of Chemical Ecology 27 679-695. 

Degen, T., Dillman, C., Marion-Poll, F., and Turlings, T.C.J. 2004. High genetic variability of herbivore-induced volatile emission within a broad range of maize inbred lines. Plant Physiology 135 1928-1938. 

The procedures for irradiation, collection, and analysis of the volatile compounds have all been described (1, 2, 3, 5, 7, 9, 11). A cryogenically programmed gas chromatograph coupled to a rapid scanning mass spectrometer provided for the analysis of the volatile components isolated from several irradiated meats and lipid substances (6). These studies have now been extended to include other component substances in order to acquire still further understanding of the source of the irradiation-induced volatile compounds from among the various meat constituents. 

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