Host location

Genna, R. L., Mordue, W., Pike, A. W., and Mordue (Luntz) A. J. (2004). Identification of semiochemicals involved in sea lice host location, and their potential use in pest control. In Annual Meeting of the International Society ofChemical Ecology, July 2004, Ottawa, Canada. 

Madubunyi, L. C., Hassanali, A., Ouma, W., Nyarango, D., and Kabii, J. (1996). Chemo-ecological role of mammalian urine in host location by tsetse, Glossina spp. (Diptera Glossinidae). Journal of ChemicalEcology 22,1187-1199. 

Some aspects of plant variation could interfere with the impact of natural enemies. Some enemies may be unable to associate microhabitat cues (e.g., chemical, physical, color, position) with prey or host location. For these enemies, prey or host feeding on restricted tissues will tend to appear widely spaced and they may not be readily encountered. It appears to me that many, if not most, parasitoids and predators can be found to use one or more cues. This negative effect could be counteracted by increased encounter rates during herbivore searching movements. 

Conifer monoterpenes (mainly a-pinene, -pinene, myrcene, limonene/phel-landrene) elicited antennal responses in tree-killing bark beetles. These components have potential behavioural roles in host location and discrimination [379]. 

The role of plant volatiles as prey and host location cues... 

McCall, P. J., Turlings, T. C. J., Lewis, W. J. and Tumhnson, J. H. (1993). Role of plant volatiles in host location by the specialist parasitoid Microplitis croceipes Cresson (Braconidae, Hymenoptera). Journal of Insect Behavior 6 625-639. 

Meiners, T. and Hilker, M. (1997). Host location in Oomyzus gallerucae (Hymenoptera Eulophidae), an egg parasitoid of the elm leaf beetle Xanthogaleruca luteola (Coleoptera Chrysomelidae). Oecologia 112 87-93. 

Meiners, T., Westerhaus, C. and Hilker, M. (2000). Specificity of chemical cues used by a specialist egg parasitoid during host location. Entomologia Experimentalis et Applicata95 151-159. 

Roth, J. P., King, E. G. and Thompson, A. C. (1978). Host location by the tachinid Lixophaga diatreae. Environmental Entomology 7 794-798. 

Steinberg, S Dicke, M. and Vet, L. E. M. (1993). Relative importance of infochemicals from 1st and 2nd trophic level in long-range host location by the larval parasitoid Cotesia glomerata. Journal of Chemical Ecology 19 47-59. 

Baarlen, P. V., Topping, C. J. and Sunderland, K. D. (1996). Host location by Gelis festinans, an eggsac parasitoid of the linyphiid spider Erigone atra. Entomologica Experimentalis etApplicata 81 155-163. 

The second technique utilized frontalure which was placed as a bait on dead- or non-host trees in an attempt to suppress southern pine beetle spot growth (15). Since the technique employs chemical cues that the natural enemies utilize, i.e. kairomones in host location, it probably has little detrimental affect on the adult predators. However, the use of inhibitors and their impact on natural enemies is not known. The data base is lacking and we can only express concern. 

In all the chemolocation assays with pea crabs, the attraction of crabs from each host race to their respective host was substantially less than 100%, and some crabs chose incorrect hosts, suggesting that there may still be at least the potential for gene flow among populations. These experiments were conducted with adult crabs, and host location experiments with larval or post-larval forms that are normally responsible for initial host selection might be particularly informative. Nevertheless, this series of studies suggests that within-species differences in chemically mediated host location may lead to population subdivision and reproductive isolation among marine species. 

Ache, B.W., The experimental analysis of host location in symbiotic marine invertebrates, in Symbiosis in the Sea, Vernberg, W.B., Ed., University of South Carolina Press, Columbia, South Carolina, 1972, 45. 

The external cuticle of insects is covered by a waxy layer composed of mixtures of hydro-phobic lipids that include long-chain alkanes, alkenes, wax esters, fatty acids, alcohols, aldehydes, and sterols. The primary purpose of this layer is to maintain water balance and prevent desiccation, as described in Chapter 6, but many of the cuticular lipid components have important secondary roles as intraspecific contact chemical signals (pheromones). These roles include species and sex recognition during reproductive interactions, and nestmate recognition and other colony organization functions in social insects. Thus, these compounds are essential mediators of insect behaviors. Cuticular compounds are also exploited by parasitoids and predators as interspecific contact cues (kairomones) to aid in host location. 

Bailey RJE, Birkett MA, Ingvarsdottir A, Mordue (Luntz) AJ, Mordue W, O Shea B, Pickett JA, Wadhams LJ (2006) The role of semiochemicals in host location and non-host avoidance by salmon louse (Lepeophtheirus salmonis) copepodids. Can J Fish Aquat Sci 63 448 -56... 

Ingvarsdottir A, Birkett MA, Duce I, Genna RL, Mordue W, Pickett JA, Wadhams U, Mordue (Luntz) AJ (2002a) Semiochemical strategies for sea louse control host location cues. Pest Manag Sci 58 537-545... 

The mechanisms whereby parasitoids use kairomones to locate hosts are obviously of crucial importance in predator-prey interactions and may be divided in two categories depending on whether they are the result of long range or cole-range chemoreception. In some cases, olfaction can be influenced by the parasitoid s previous experience (551). A number of kairomones used by parasitoids as aids in host location have been identified. Hemolymph, cuticule, frass scale, mandibular gland and feces can be sources of such kairomones, and long-chain hydrocarbons are the main chemical stimuli responsible (150, 552-569). 

Weseloh, R.M. Host Location by Parasitoids. In D.A. Nordlung, R.L. Jones, and W.J. Lewis eds., Semiochemicals Their Role in Pest Control, p. 79-95. New York John Wiley Sons 1981. 

Long-range cues important in potential host community location and host location may emanate from the host, its food, shelter, or associated organisms. Short-range cues important in host location, examination, ovipositor probing, drilling and acceptance usually come from the host. Further, the same source and chemical may act as a pheromone in one context and a kairomone or synomone in others. 

Host sex pheromones can serve as cues to host location for several parasitoid species (Kennedy, 1979 Sternlicht, 1973). Prokopy and Webster (1978) found that the marking pheromone of Rhagoletis pomonella stimulates oviposition probing of Opius lectus. 

Some of the early work on parasitoid host location involved non-living host food. Thorpe and Jones (1937) found that Venturia canescens is attracted to the odor of oatmeal. Meat odor was found to be attractive to Alysia manducator and Nasonia Mormoniella) vitripennis (Laing, 1937). Since the source and nature of the responsible chemicals was not determined, it may be that microorganisms were involved. 

Lawrence, P. O. (1981) Host vibration A cue to host location by the parasite, Biosteres longicaudatus. Oecologia, 48, 249-51. 

Orphanides, G. M. and Gonzales, D. (1970) Effects of adhesive materials and host location on parasitization by uniparental race of Trichogramma pretiosum. J. Econ. Ent., 63, 1891-8. 

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