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1
Otienoburu, Philip E. "Plant Semiochemicals as Mosquito Attractants." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1313605670.
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Zabaras, Regina, University of Western Sydney, of Science Technology and Environment College, and of Science Food and Horticulture School. "The evolution of semiochemicals in Australian marsupials." THESIS_CSTE_SFH_Zabaras_R.xml, 2003. http://handle.uws.edu.au:8081/1959.7/759.
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The aim of this project was to study the nature and relative proportion of the volatile components in the sternal-gland secretions obtained from a wide range of Australian marsupials.The results obtained were then used to investigate the evolution of semiochemicals in Australian marsupials by using the current phylogenetic tree as a template.The initial part of the study was dedicated to the investigation of some of the techniques available for the sampling and analysis of gland secretions. Individuals from 8 families within the Marsupialia and 1 family from the Monotremata were sampled over an 18 month period.The obtained results were then subjected to multivariate statistical analysis followed by cladistic analysis.In several species the secretion composition was found to be affected by the breeding status of individuals for both genders.Many other factors such as animal-age, hierarchical status, diet,and lifestyle were also observed to affect the secretion composition. Finally, cladistic analysis demonstrated the differences in the levels of divergence at the species, familial and ordinal levels and highlighted secretion components that could be used to differentiate between super families, species and even sexual status of individuals.Master of Science (Hons)
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Zabaras, Regina. "The evolution of semiochemicals in Australian marsupials." Thesis, View thesis View thesis, 2003. http://handle.uws.edu.au:8081/1959.7/759.
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The aim of this project was to study the nature and relative proportion of the volatile components in the sternal-gland secretions obtained from a wide range of Australian marsupials.The results obtained were then used to investigate the evolution of semiochemicals in Australian marsupials by using the current phylogenetic tree as a template.The initial part of the study was dedicated to the investigation of some of the techniques available for the sampling and analysis of gland secretions. Individuals from 8 families within the Marsupialia and 1 family from the Monotremata were sampled over an 18 month period.The obtained results were then subjected to multivariate statistical analysis followed by cladistic analysis.In several species the secretion composition was found to be affected by the breeding status of individuals for both genders.Many other factors such as animal-age, hierarchical status, diet,and lifestyle were also observed to affect the secretion composition. Finally, cladistic analysis demonstrated the differences in the levels of divergence at the species, familial and ordinal levels and highlighted secretion components that could be used to differentiate between super families, species and even sexual status of individuals.
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Zabaras, Regina. "The evolution of semiochemicals in Australian marsupials." View thesis View thesis, 2003. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030402.151527/index.html.
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Thesis (M.Sc. (Hons.)) -- University of Western Sydney, 2003."A thesis presented in partial fulfilment of the requirements for the degree of Master of Science (Honours), College of Science, Technology and the Environment, University of Western Sydney ... January, 2003" Bibliography : leaves 142-150.
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Nordin, Ove. "Stereoselective synthesis of semiochemicals related to pine sawflies." Doctoral thesis, KTH, Chemistry, 1999. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-2852.
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This thesis describes the stereochemistry and charactericsof ()-1,6-germacradien-5-ol, isolated from the larvaldefence substance of the pine sawflyNeodiprion sertiferand from the needles of Scots pine,Pinus sylvestris. The conformational behaviour of thissesquiterpene alcohol was investigated by molecular mechanicsstudies (MM2) and NMR. The absolute configuration at the twostereogenic centres was established as (5S,8S), after NOE measurements and chemical transformationinto ()-α-cadinol and 1-endo-bourbonanol. Our studies towards a stereoselectivetotal synthesis of ()-1,6-germacradien-5-ol using ringclosing metathesis (RCM) is also reported. However, allattempts to prepare this germacrene alcohol and other1,6-cyclodecadien systems using RCM failed.
Pseudomonas cepacialipase (PCL) catalysed acylation ofprimary 2-methylalcohols with vinyl acetate is anenantioselective reaction. The enantioselectivity of PCLtowards a series of primary 2-methylalcohols were studied. Highenantiomeric ratios,E>100, were observed for2-methyl-3-aryl-1-propanols, where aryl is 2-thiophene,3-thiophene, 2-furan and phenyl. In contrast the selectivitywas rather low for other 3-substituted primary2-methylpropanols such as 3-alkyl and 3-cycloalkyl, E ≈10 - 20. When moving the thiophene ring closer or further awayfrom the stereogenic centre a dramatic decrease in E wasobserved. 2-Isopropyl-5-methyl-5-hexen-1-ol, a possiblebuilding block for the total synthesis of1,6-germacradien-5-ol, was also successfully resolved with PCL,E= 14.
Keywords:defence substance, 1,6-germacradien-5-ol,Neodiprion sertifer,Pinus sylvestris, molecular mechanics, configuration,metathesis, RCM, stereoselective, kinetic resolution,transesterification, lipase,Pseudomonas, PCL, 2-methylalcohol, 2-isopropylalcoholenantioselective.
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Santangelo, Ellen M. "Stereoselective syntheses of semiochemicals : applications in ecological chemistry /." Stockholm : Organic Chemistry, Department of Chemistry, Royal Institute of Technology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-74.
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Meade, Brian J., and mikewood@deakin edu au. "Semiochemicals in merino ewes: Field effects and chemical identification." Deakin University. School of Sciences, 1986. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20050815.112723.
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Gurney, Joanne Elizabeth. "The use of semiochemicals for vertebrate pest population control." Thesis, University of York, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273829.
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Henry, Elizabeth Judith. "The synthesis of insect sex pheromones." Thesis, Bangor University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.481279.
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Nilsson, Anna. "Identification and Syntheses of Semiochemicals Affecting Mnesampela privata and Trioza apicalis." Licentiate thesis, Mid Sweden University, Department of Natural Sciences, Engineering and Mathematics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-10596.
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The Autumn gum moth, Mnesampela privata (Lepidoptera: Geometridae) is an endemic Australian moth whose larvae feed upon species of Eucalyptus. The moths favorite host plants are E. globulus and E. nitens which are the most important species used in commercial plantations of the Australian pulpwood industry. The autumn gum moth has become one of the most significant outbreak insects of eucalyptus plantations throughout Australia. As a consequence great financial losses to the forest industry occur. Today insecticides such as pyrethroids are used for control of eucalyptus defoliators as M. privata.
The carrot psyllid, Trioza apicalis (Homoptera: Psylloidea), is one of the major pests of carrot (Daucus carota) in northern Europe. The psyllid causes curling of the carrot leafs and reduction of plant growth. Today the carrot crops are protected with the pyrethroid insecticide cypermethrin, which is toxic to aquatic organisms and is, from 2010, prohibited for use in Sweden by the Swedish Chemicals Inspectorate.
An alternative to insecticides is to protect the seedlings with semiochemicals, a chemical substance or mixture of them that carries a message. This thesis describes the identification and the syntheses of semiochemicals from the above mentioned insect species.
From analysis of abdominal tip extracts of M. privata females from Tasmania a blend of (3Z,6Z,9Z)-3,6,9-nonadecatriene and (3Z,6Z,9Z)-3,6,9-heneicosatriene was identified as the sex pheromone of this species. The identification of the C19- and C21-trienes was confirmed by synthesis.
In the analysis of carrot leaf extracts we found a compound, α-cis-bergamotene, that induces antennal response in the carrot psyllid. This is just the beginning of the studies of trying to manipulate this psyllid with semiochemicals instead of insecticides.
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Hayes, Richard Andrew, of Western Sydney Hawkesbury University, Faculty of Science and Technology, and School of Science. "Semiochemicals and social signalling in the wild European rabbit (Oryctolagus cuniculus(L.)." THESIS_FST_SS_Hayes_R.xml, 2000. http://handle.uws.edu.au:8081/1959.7/371.
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The European rabbit lives in defined social groups of between two and about twenty individuals. There are distinct social hierarchies within each group. Rabbits are known to scent-mark their environment with secretions from several glands, and the secretion of the submandibular cutaneous gland is strongly correlated with social status. Dominant, male rabbits have a higher secretory activity of the gland, and show much more scent-marking behaviour than do any other individuals within the social group. This study was principally conducted at Hope Farm, Cattai National Park in New South Wales, Australia.The proteinaceous components of the secretion varied between individuals, but the protein profile of an individual did not change over time.It was found that dominant rabbits chin mark preferentially at the entrances to warrens, and at the boundaries of their territory.The work in this study provides new insights into the way that rabbit semiochemical messages work. The difference between the secretion of a subordinate and a dominant rabbit appears to be due to the presence or absence of one compound, 2-phenoxy ethanol. This compound, with known fixative properties, supports the idea that the only difference between dominant and subordinate secretions is whether or not they persist in the environment after marking. Such a mechanism for asserting dominance may be much more common in mammals than is apparent from the published literatureDoctor of Philosophy (PhD)
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Hayes, Richard Andrew. "Semiochemicals and social signalling in the wild European rabbit (Oryctolagus cuniculus (L.)) /." View thesis View thesis, 2000. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030424.112701/index.html.
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Thesis (Ph.D.) -- University of Western Sydney, Hawkesbury, 2000.A thesis presented to the University of Western Sydney, Hawkesbury, in partial fulfilment of the requirements for the degree of Doctor of Philosophy, December, 2000. Includes bibliographical references.
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Curtiss, Robert T. "Attractiveness of semiochemicals to green lacewings for biological control in pome fruit." Online access for everyone, 2008. http://www.dissertations.wsu.edu/Thesis/Spring2008/R_Curtiss_050808.pdf.
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Buteler, Micaela. "Integrated management of the Wheat Stem Sawfly by exploiting semiochemicals to enhance trap crops." Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/buteler/ButelerM0508.pdf.
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The wheat stem sawfly, Cephus cinctus Norton (WSS) causes significant damage in cereal crops in the northern Great Plains of North America. Recently, the use of winter wheat as a trap crop to protect spring wheat from this insect pest in a wheat-fallow cropping system was evaluated, yielding promising results. Subsequently, the overall objective of this dissertation research was to improve the efficacy of winter wheat trap crops to manage the WSS. Oviposition behavior studies in the presence of hosts infested by conspecifics showed that WSS did not avoid infested hosts. These results confirmed the potential of a trap to provide a sink for multiple eggs, resulting in increased WSS mortality due to cannibalism. I identified suitable winter wheat cultivars based on agronomic characteristics that influence WSS behavior in conjunction with the emission of behaviorally active plant volatiles, as well as the performance of the cultivars in the area where the pest occurs. Results from this study identified five cultivars, Norstar, Morgan, BigSky, Neeley, and Rampart, with good potential as trap crops. Norstar emitted greater amounts of attractive volatile compound ß-ocimene, and was the preferred host in greenhouse choice tests. Based on these results, a perimeter trap cropping trial comparing three winter cultivars as traps (Norstar, Neeley and Rampart) to protect spring wheat was conducted for two consecutive years. Two spring wheat cultivars differing in suitability for infestation by sawflies were chosen as the main crop. WSS abundance was significantly greater in the winter wheat traps than in the adjacent unattractive spring cultivar Conan both years of the experiment and greater than an attractive spring cultivar Reeder in 2005. No differences in infestation were observed between winter cultivars, although greater numbers of eggs were found in Norstar than in Rampart traps. Swathing the trap crop before grain fill killed most larvae developing in the trap crop. Finally, I investigated the effect of a synthetic attractive compound, (Z)-3-hexenylacetate, on oviposition and found that application of this compound in a lanolin paste resulted in increased oviposition by females in greenhouse choice tests. The results obtained suggest that a trap cropping management strategy involving attractive and unattractive cultivars, and semiochemically assisted trap cropping by application of synthetic host volatiles, show potential to manage the WSS.
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ARIF, Mokhtar. "Chemical ecology of Bagrada hilaris (Burmeister) (Heteroptera: Pentatomidae): intraspecific and interspecific chemical cues." Doctoral thesis, Università degli Studi di Palermo, 2020. http://hdl.handle.net/10447/395181.
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The chemical ecology of Heteroptera insects is determined by a wide array of chemical signals (semiochemicals) that drive their behavior at intra- and inter-specific level. Intraspecific semiochemicals are called pheromones, interspecific chemicals are named allelochemicals. In the case of stink bugs, sex-pheromones and aggregation pheromone are produced by adult males. Furthermore, phytophagous stink bugs exploit chemical cues emitted from plants to find a suitable food and oviposition source. The semiochemicals involved in this process are named kairomones and are generally formed by specific blend or key odorants emitted from host plant. The chemical ecology of the phytophagous Pentatomid species Bagrada hilaris, or Painted bug, native from Asia and invasive in the Americas is characterized by similarities and differences with the other stink bugs. In particular at intraspecific level is been observed that males volatiles attract females, and chemicals analyses showed that both adults produced a similar pattern of chemicals, with the only quantitative difference related to (E)-2-octenyl acetate, produced in higher amounts from males. However, the possible attractant role of this compound at intraspecific level is still to be assessed. Moreover at interspecific level, although B. hilaris is reported to be highly attracted to brassicas, few studies have attempted to elucidate the chemicals cues exploited in its host location process. In the specific, the chemicals cues exploited from this pest in the location of host plant at seedling stage, the stage more vulnerable and subjected to the attack from B. hilaris have still never been investigated.
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Chinta, Satya Prabhakar [Verfasser], and Stefan [Akademischer Betreuer] Schulz. "Identification and synthesis of semiochemicals from arthropods / Satya Prabhakar Chinta ; Betreuer: Stefan Schulz." Braunschweig : Technische Universität Braunschweig, 2010. http://d-nb.info/1175828076/34.
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Burhani, Joseph. "Role of semiochemicals in oviposition and mating behaviour of Aedes aegypti (Diptera: Culicidae)." Thesis, Keele University, 2013. http://eprints.keele.ac.uk/194/.
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Aedes aegypti (Diptera: Culicidae) is the major vector of a number of arboviruses including dengue. Understanding how semiochemicals might mediate the key behaviours of mating and oviposition should lead to a better understanding of the biology of Aedes aegypti and might also lead to practical vector control applications. The results of behavioural investigations into putative egg associated oviposition pheromone have been contradictory and incomplete in that they failed to control numbers of eggs in their experimental design. A previous study found behavioural evidence for a male produced sex pheromone, but an upwind anemotactic response of females was not tested and it could be argued that the experimental design was not robust. For this thesis no-choice and choice bioassays were carried out to test the oviposition response of gravid females to both specific numbers of con-specific eggs and methanol extract of eggs. An olfactometer was designed to test the upwind anemotactic response of virgin females to male headspace volatiles with and without host odour cues. These male odours were also used to bait BG-sentinel traps in the field. While no evidence was found that was consistent with an egg associated oviposition pheromone in Aedes aegypti, results from both laboratory and field based experiments suggest that males might emit a pheromone in response to host odour that attracts virgin females. Results from experiments in which males were not exposed to host odour suggest that host odour might be required to stimulate pheromone release.
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Grosman, Donald Michael. "Southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Scolytidae) : quantitative analysis of chiral semiochemicals /." Diss., This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-05042006-164540/.
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Garraway, Richard. "The action of semiochemicals on olfactory nerve activity and behaviour of Deroceras reticulatum (Mull)." Thesis, University of Portsmouth, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303955.
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Losey, Stephen M. "Orientation and dispersal of Cryptolestes ferrugineus (Stephens) (Coleoptera: Laemophloeidae) in response to various semiochemicals." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/20566.
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Master of ScienceDepartment of Entomology
Thomas W. Phillips
The rusty grain beetle, Cryptolestes ferrugineus (Stephens) (Coleoptera: Laemophloeidae), is a very common worldwide pest of stored grains. The orientation of C. ferrugineus beetles to various semiochemicals was studied in both the laboratory and field. In laboratory experiments glass two-choice pitfall bioassay dishes were used. Mixed-sex populations of beetles responded positively and significantly to cucujolide I and II separately and in combination compared to controls. Bioassays using the two aggregation pheromones of the lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae). Dominicalure 1 and 2 together elicited unexpected significant attractive responses by C. ferrugineus as did assays with the synthetic pheromones from other species. Bioassays showed that C. ferrugineus were not attracted to either corn meal or rolled oats, but they were attracted to commercial grain-based lures and also to ethanol, a natural fermentation product from grains. Several bioassays were conducted to test the attractiveness of naturally produced beetle volatiles to C. ferrugineus, but these showed no orientation to volatiles from either the beetles or their food only. Field tests were conducted in Kansas to test attractiveness of the synthetic pheromones cucujolide I and II in lures together with wheat versus wheat only as a control using Lindgren funnel traps. Field tests in 2014 with cucujolide II pheromone lures showed a significant response by feral C. ferrugineus when tested against wheat. Other field tests to examine dispersal of C. ferrugineus relative to grain storages showed that more C. ferrugineus were caught on the western side of grain bins compared to other cardinal directions at two different locations. Results from field and laboratory studies suggest that semiochemical-based tools can be developed to study dispersal behavior in field populations of C. ferrugineus.
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Tarver, Matthew Robert. "Influence of soldier derived semiochemicals on Reticulitermes flavipes worker caste differentiation and gene expression." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0025142.
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Liu, Youngbiao. "Biology of Gnathotrichus retusus and behavioural responses of G. retusus and G. sulcatus to semiochemicals." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/26441.
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Gnathotrichus retusus is primarily univoltine with a minor fraction of the population taking more than one year to complete the life cycle. From the spring to the summer, the development of brood from egg to adult took about 40 days or more in Douglas-fir logs. Brood production was significantly related to the gallery length. Boring activities were not consistently related with temperature, shifting from shallow sapwood to deep sapwood over time. Fungal staining was usually limited to the wood near the gallery entrance, and became darker in colour over time beginning in June. Abandonment of some galleries mainly occurred in June and July by females, and was probably induced by high temperatures.
G. retusus preferred Douglas-fir stumps to western hemlock stumps, but both host tree species were equally suitable for G. retusus brood development. Significant differences were found among individual Douglas-fir and western hemlock stumps in attack density and brood production. Within a stump, attack density and brood production for Douglas-fir, and attack density for western hemlock increased from the stump top to the bottom.
G. retusus emergence from Douglas-fir and western hemlock stumps and G. retusus and G. sulcat us flights began in late April when the daily maximum temperature reached 13.5°C, and peaked in late May. Brood emergence of G. retusus ceased, with rare exception, in late June. G. retusus had only one big peak flight while G. sulcatus had a small second peak flight in late July. Seasonal flights ceased in October when weekly mean maximum temperatures dropped below 15°C. Brood emergence, seasonal flights, and the sex ratios of brood ready to emerge and captured flying beetles were positively correlated with maximum temperature.
G. retusus had a bimodal diurnal flight rhythm: a very small morning flight and a much larger dusk flight. Light intensity seemed to be a major stimulus in initiating the flight. However, diurnal flight might also be influenced by both temperature and relative humidity.
Both G. retusus and G. sulcatus of both sexes responded significantly to ethanol or their own aggregation pheromones, (+)-sulcatol and (±)-sulcatol respectively, and ethanol was a synergist of (+)-sulcatol for G. retusus of both sexes. Alpha-pinene was neither a primary host attractant nor a synergist of aggregation pheromones. The sex ratios (female/male) of both species increased significantly from less than one for host chemicals alone to above one for treatments including aggregation pheromones. The sex ratio of G. sulcatus increased with increases in release rates of (±)-sulcatol.Forestry, Faculty of
Graduate
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Banks, Glyn Raymond. "Analysis and identification of potential semiochemicals in the scent-markings of the tiger, Panthera tigris." Thesis, Anglia Ruskin University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313206.
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Bouwer, Marc Clement. "Identication of semiochemicals from four major insect pests of Eucalyptus and Pinus species in South Africa." Thesis, University of Pretoria, 2014. http://hdl.handle.net/2263/78160.
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The chemical ecology for key insect pests in South Africa's commercial Pinus and Eucalyptus
plantations are explored in this thesis. The main aim was to discover and
characterize semiochemical compounds that explain certain behaviours of the insects
involved, and that could potentially be exploited in future for the manipulation of the
insects' behaviour. Such formulations are sought after because they can be applied in
environmentally friendly pest management techniques. Semiochemical interactions were
studied in four di erent biological systems. These included the sex pheromone communication
system for the Cossid moth, Coryphodema tristis; allelochemical interactions
between the Eucalyptus weevil Gonipterus spp. and their Eucalyptus host; allelochemical
interactions between Sirex noctilio's, symbiotic fungus, Amylostereum areolatum and
its biological control agent Ibalia leucospoides; and allelochemical interactions between
the egg clutches of Thaumastocoris peregrinus and its biological control agent Cleurocoides
noackae. Semiochemical compounds were found and identi ed through analysis
techniques that included gas chromatography coupled to electroantennography (GCEAD)
and gas chromatography coupled to mass spectrometry (GC-MS). Some of these
semiochemical interactions were complex involving combinations of di erent chemical
cues, such as the host recognition cues identi ed for Gonipterus species and potential
cues between T. peregrinus females and their egg clutches. Other speci c interactions
were found to be simpler and relied on a few speci c chemicals. These included the
sex pheromone communication between C. tristis adults and the interaction occurring
between female I. leucospoides wasps and the mutualistic fungus of their prey, namely
A. areolatum. Biological activity was investigated only for compounds with con rmed
identity and included the sex pheromones of C. tristis and some of the chemicals identi
ed from the egg clusters of T. peregrinus. These tests were conducted in laboratory
and eld conditions. Biological activity was proven for the identi ed sex pheromone of
C. tristis during eld trials conducted in 2011 and 2013. One of the chapters was published
and another submitted for publication in a peer reviewed journal. Two provisional
patents were also registered from this work.Thesis (PhD)--University of Pretoria, 2014.
Chemistry
PhD
Unrestricted
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Kirkland, Dean Lee. "The use of semiochemicals to enhance the natural control of pests of arable crops by invertebrate predators." Thesis, University of Edinburgh, 1999. http://hdl.handle.net/1842/28368.
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The electrophysiological and behavioural responses of the aphidophagous hoverfly Episyrphus balteatus Degear, and polyphagous ground beetles Pterostichus melanarius Illiger and Nebria brevicollis Linneaus, to a range of volatile semiochemicals were studied. Phacelia tanaectfiolia flower extract, Nepeta cataria whole plant extract, and (E)-β-farnesene where found to be attractive to the predators in laboratory and windtunnell assays. Field trials demonstrated that the attractive semiochemicals could be placed in dispensers in arable crops to increase the amount of predators present throughout the field system. There was also a corresponding decrease in the number of pest species present in the treated field plots relative to the control plots. Phacelia flower extract was found to have the greatest effects on predator and prey numbers. The mechanisms of the reduction in prey numbers were studied using exclusion experiments in the field and enzyme linked immunosorbant assays on the gut contents of the predators. There was found to be a link between the increased rates of predation in the field and the decline in pest numbers. The potential of semiochemicals to enhance natural control of crop pests is discussed.
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Hull, Mark Q. "The role of semiochemicals in the behaviour and biology of Lepeophtheirus salmonis (Kroyer, 1837) : potential for control?" Thesis, University of Aberdeen, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310772.
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The role of semiochemicals in the behaviour and biology of Lepeophtheirus salmonis was investigated using a range of techniques. The potential use of semiochemicals in the behavioural ecology of mobile stages was examined using longitudinal monitoring and experimental manipulation of laboratory reared single cohort populations. The chronic and long term effects of separation from the host were also investigated using similar populations. The nature and chemosensory capability of the sense system of the parasite was assessed through morphological and ultrastructural studies. Finally, the nature of potential chemical stimuli during initial copepodid settlement, pair formation and mating, and host re-attachment of mobile stages, was examined using both in vitro and in vivo techniques. Longitudinal monitoring of populations created a model for mobile development and the timing and processes of pair formation and mating. There was evidence of a hierarchy of pair formation between female stages, periods of strong mate competition between males, and many factors within the processes were defined. Survival off the host was strongly related to the developmental stage and/or size of the louse; with adult females surviving for the longest and preadult I males for the shortest periods. The ability of adult males to re-attach and subsequently persist on the host was significantly reduced after only 72 hours of separation. Very few potential chemosensory setae were found on the appendages examined, the exception to this being the antennule. Two distinct populations of setae on the distal (14 setae) and proximal (27 setae) articles of the antennule demonstrated a wide range of morphology. The internal organisation, innervation and ultrastructure of these antennular setae was examined in detail. The setae could be divided into at least 6 distinct categories, when the internal data were combined with the external morphology.
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Ukeh, Donald A. "The identification and use of semiochemicals for the control of the maize weevil, Sitophilus zeamais (Motschulsky) in Nigeria." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2008. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=25167.
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Dodds, Catherine Jane. "The action of naturally-occuring semiochemicals on feeding behaviour and neurophysiology of the field slug Deroceras reticulatum (Mueller)." Thesis, University of Portsmouth, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310443.
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Costa, Arnaud. "Aggregation, dispersal and edge behavior of the bark beetle predator Thanasimus dubius (Coleoptera: Cleridae); potential use in biological control." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/dissertations/129.
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Bark beetles are major pests of pine forests in North America that can inflict considerable damage and cause severe economic loss. The checkered beetle Thanasimus dubius Fabricius (Coleoptera: Cleridae), an abundant predator in the Eastern USA and Canada, has been suggested to influence the dynamics of several bark beetles, including the economically important southern pine beetle (SPB), Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae). Because of the importance of T. dubius in pine forests, I studied several aspects of T. dubius biology including both its chemical and dispersal ecology. I first present an experiment that was conducted to improve the rearing system of T. dubius so that sufficient numbers of predators could be produced more efficiently for both behavioral and ecological studies. Improvements to the rearing method potentially could be achieved by adding a preservative to increase the shelf-life of the diet used to feed larval T. dubius thereby allowing feeding intervals to be extended. To evaluate this, I added sorbic acid, a preservative, to the larval diet at three different concentrations (0, 0.1 and 0.2%) and for two different intervals between feedings (2-3 vs. 5 days). Additionally, I measured potential deleterious effects of this preservative on predator performance (i.e., female fecundity). I then assessed the effect of this predator on SPB survival by releasing newly hatched T. dubius larvae at several densities (0, 50 100, and 200) on pine logs infested by SPB. I also studied the chemotactic response of this predator toward various volatiles such as prey pheromones or tree volatiles in a wind tunnel. I developed a method that associated upwind flight behavior and antennal behavior to quantify the relative attractiveness of each tested source of chemical. I then conducted three experiments to investigate the ability of individual T. dubius to respond to different prey olfactory signals (bark beetle pheromones) and assess their potential for learning. First, I examined individual predator preferences toward three major prey pheromones (ipsenol, ipsdienol, and frontalin) in a study that combined a mark-release-recapture experiment with a field choice test. I also measured the responses of individual wild T. dubius in a wind tunnel, which allowed the testing of a wider range of semiochemicals (frontalin, ipsenol, ipsdienol, sulcatol, and α-pinene). A final wind tunnel experiment tested the ability of naive predators to learn two prey pheromones, frontalin and ipsenol, that were presented alone or associated with a reward. In the last chapter, I quantified the dispersal of this predator and its behavior along an edge separating a pine forest from a non-suitable habitat. I analyzed T. dubius distribution and movement in the field relative to its bark beetle prey Ips grandicollis Eichhoff (Coleoptera: Curculionidae) and to the root feeder Dendroctonus valens LeConte (Coleoptera: Curculionidae). These three insects are associated with the phenomenon of red pine decline in the Great Lakes area. Thus, understanding the relative pattern of movements of these three beetles could provide considerable knowledge on the spatial and temporal progression of red pine decline by, for instance, assessing the connection between existing pockets. I estimated the dispersal quantiles for this predator relative to its bark beetle prey and determined whether dispersal behavior was relatively homogeneous (one kind of disperser) or heterogeneous (two kinds). In a second part, I sampled the abundance of T. dubius, I. grandicollis, and D. valens along transects set between a matrix area constituted by a clearing and a habitat zone composed of red pine forest. I further developed a diffusion model, including a constant k (corresponds to the ratio of densities along the edge), that permits characterization of beetle behavior around the boundary. Studies developed in the present dissertation, therefore, investigated several aspects of T. dubius ecology: predation on SPB, ability to respond to an olfactory signal, and dispersal traits. I first showed that augmentation with larval T. dubius can successfully reduce the SPB ratio of increase in infested pine logs. I also developed a system of rearing T. dubius that was more efficient and could allow larger numbers of predators to be produced. Sorbic acid did not reduce adult lifetime or size but did affect female fecundity (20 - 40% reduction). Increasing feeding time interval to 5 days (instead of 2-3 days) improved the efficiency of the system, even when sorbic acid was not added in the diet. Wind tunnel experiments present a methodology that could enable future quantification of the relative attractiveness of various semiochemical treatments. I identified a particular antennal behavior, which I called "stand up antennal" that was typically produced when the insect was attracted to a semiochemical. The choice tests in the field and the wind tunnel experiment using wild adults both showed that T. dubius individuals are generalists that are flexible in their response to a broad range of semiochemical signals (frontalin, ipsenol, ipsdienol, sulcatol, and α-pinene). I demonstrate that naive predators are more attracted toward ipsenol after having experienced conditioning with this kairomone via a reward. Finally, experiments on dispersal and edge behavior revealed that T. dubius and one of its common prey, the bark beetle I. grandicollis, exhibit a different pattern of movement within red pine stands and surrounding habitats. First, adult T. dubius can disperse substantially further (50% dispersed beyond 1.54 km) than I. grandicollis adults (50% dispersed beyond 0.13 km). Second, T. dubius was highly affected by the presence of an edge, showing a step-like pattern with very predators caught in unsuitable areas. Conversely, the behavior of I. grandicollis was less limited by such a boundary. As with T. dubius, the root colonizer D. valens showed a strong edge behavior that was characterized by avoiding matrix zones.
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Jones, Perer R. H. "An investigation of the semiochemicals of the Mediterranean black scale Saissetia oleae and the olive bark beetle Phloeotribus scarabaeoides." Thesis, Cardiff University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491915.
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Okal, M. N. "Analysing the role of semiochemicals in the oviposition substrate choices of the malaria vector mosquito Anopheles gambiae sensu lato." Thesis, London School of Hygiene and Tropical Medicine (University of London), 2015. http://researchonline.lshtm.ac.uk/2528132/.
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The search for tools that target malaria vector that resist insecticides and bite outdoors has become a research priority. Such tools will be necessary for managing residual malaria transmission and hastening the eradication of this devastating disease. This study investigated chemicals that potentially affect the oviposition substrate choices of Anopheles gambiae sensu lato (s.l.). It is foreseen that increased knowledge of the oviposition behaviour of this major malaria vectors and chemicals cues that mediate oviposition site-selection can be applied in the development of additional sampling methods and alternative interventions that to trap gravid malaria mosquitoes outdoors. To achieve a reproducible high egg-laying success of An. gambiae sensu stricto (s.s.) and An. arabiensis four factors were evaluated: (1) the time provided for mating; (2) the impact of cage size, mosquito age and female body size on insemination; (3) the peak oviposition time; and, (4) the host source of blood meals. Then four bioassays were optimised for studying oviposition responses of An. gambiae s.s. in the laboratory and semi-field conditions: a WHO-tube bioassay and a wind-tunnel that detected short-range attraction in the laboratory; a two-tier choice egg-count bioassay that compared the relative proportion of eggs laid in substrates in the laboratory; and a modified BG Sentinel mosquito gravid trap that evaluated long-range attraction of gravid females to olfactory cues in the semi-field. Finally, the oviposition responses of gravid An. gambiae s.s. mosquitoes to water vapour, Bermuda grass hay infusion (hay infusion), and putative semiochemicals identified from the hay infusion and a soil infusion previously shown to elicit higher egg deposition compared to filtered Lake Victoria water (lake water) in two choice egg-count bioassays (Herrera-Varela et al. 2014), were evaluated. High oviposition rates [84%, 95% confidence interval (CI) 77-89%] were achieved when 300 male and 300 blood-fed female An. gambiae s.s. were held together in a cage for four days. The chance of oviposition in the mosquitoes dropped when human host source of blood-meal was substituted with a rabbit (Odds ratio (OR) 0.30, 95% CI 0.14-0.66) but egg-numbers per female were not affected. All four optimised oviposition bioassays effectively showed between 15-20% shifts in oviposition substrate choices of mosquitoes with 80% statistical power and 5% significance. Using the WHO-tube bioassay, gravid An. gambiae s.s. were shown to be 2.4 times (95% CI 1.3-4.7 times) more likely to move towards high humidity in still air compared to non-gravid Preamble mosquitoes. This was more pronounced in the airflow olfactometer where the gravid mosquitoes were 10.6 times (95% CI 5.4-20.8 times) more likely to fly into a chamber with water than a dry chamber. Two-choice egg-count bioassays showed that An. gambiae s.s. were less likely to lay eggs in six-day old hay infusion (OR 0.10, 95% CI 0.03-0.33) compared to lake water. Ten putative semiochemicals were identified from the hay infusion using mass spectrometry and published electrophysiology data: 4-hepten-1-ol, 4-ethylphenol, phenylmethanol, 2-phenylethanol, indole, phenol, 3-methylindole, 3-methyl-1-butanol, 4-ethylphenol, and nonanal. Tested in two-choice egg-count bioassays, the first four listed compounds had no effect on egg deposition at the tested concentrations (between 0.01-5 parts per million) but mosquitoes were less likely to lay eggs in at least one concentration of 3-methylindole (OR 0.39, 95% CI 0.21-0.71), indole (OR 0.57, 95% CI 0.37-0.87), 3-methyl-1-butanol (OR 0.32, 95% CI 0.22-0.47), phenol (OR 0.55, 0.32-0.95), 4-methylphenol (OR 0.32, 0.18-0.57) and nonanal (OR 0.66, 95% CI 0.47-0.91) compared to lake water. In contrast to the hay infusion and hay infusion volatiles, An. gambiae s.s. were about two times more likely to lay eggs in cedrol, a sesquiterpene alcohol identified from the soil infusion, compared to lake water (OR 1.84, 95% CI 1.16-2.91). Cedrol attracted twice as many gravid mosquitoes in the semi-field also (OR 1.92, 95% CI 1.63-2.27). In the field, modified BG-Sentinel traps, electrocuting nets and OviART gravid traps with lake water and cedrol were three times more likely to trap malaria mosquitoes compared to traps with water only (OR 3.3, 95% CI 1.4-7.9). In conclusion, water vapour was shown to be a strong, non-specific pre-oviposition attractant for gravid An. gambiae s.s. in still air and moving air. It is probably the long range cue that gravid An. gambiae s.l. use to detect the presence aquatic habitats beyond the range of chemical cues. Evidence showed that An. gambiae s.s. discriminate between potential oviposition substrates and that this selective process is in-part mediated by volatile organic compounds originating from the site. Water vapour leads gravid mosquitoes to aquatic sites but semiochemicals enable the mosquitoes to discriminate and select between potential habitats. It was demonstrated that synthetic equivalents of semiochemicals found to attract gravid mosquitoes such as cedrol can be used to trap malaria mosquitoes outdoors.
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Favaris, Arodí Prado. "Isolamento do cairomônio de Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) responsável pela atração do parasitoide Habrobracon hebetor Say (Hymenoptera: Braconidae)." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-23012017-152532/.
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Cairomônios são semioquímicos envolvidos nas interações interespecíficas dos insetos, que beneficiam o receptor em detrimento do emissor. Uma destas interações envolve a busca hospedeira por parasitoides, que detectam estes compostos como estratégia para localizar seus hospedeiros. No caso do ectoparasitoide larval, Habrobracon hebetor Say (Hymenoptera: Braconidae), o \'frass\' de Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) libera um cairomônio que atrai as fêmeas do parasitoide. Considerando que A. kuehniella é muito utilizada para produção de ovos, visando à criação de inimigos naturais, este cairomônio é indesejável, pois acaba favorecendo altas infestações por H. hebetor, podendo causar prejuízos expressivos ao longo do processo. Uma das soluções para o controle de tais infestações poderia ser o emprego de armadilhas com o semioquímico sintético. Entretanto, como o cairomônio ainda não foi identificado, este trabalho teve como objetivo o seu isolamento - a etapa inicial para sua identificação. O cairomônio foi extraído por meio da lavagem com solvente e aeração do \'frass\' de A. kuehniella. Os extratos foram, então, testados em olfatometria de quatro vias com fêmeas do parasitoide, registrando-se o tempo de permanência em cada tratamento. O extrato de lavagem ativo foi fracionado em coluna de sílica em cinco frações, cuja atratividade também foi averiguada para proceder com o isolamento do cairomônio. Os extratos e frações foram então analisados por cromatografia gasosa por ionização em chama (GC-FID) e espectrometria de massas (GC-MS), a fim de localizar compostos exclusivos nas amostras ativas. Além disso, as frações provenientes do extrato de lavagem foram aeradas para a extração de seus compostos voláteis e também analisadas por GC-MS. O cairomônio foi isolado na fração 75% éter, indicando ser um composto polar. Por comparação dos cromatogramas, apenas um pico na coluna HP-5ms foi selecionado como pertencente ao cairomônio. Em coluna Rtx-1ms, o pico bifurcou-se, indicando que, pelo menos, um dos compostos faz parte do cairomônio. As combinações metodológicas deste trabalho conduziram ao isolamento do cairomônio presente no \'frass\' de A. kuehniella e à seleção de pelo menos um composto que compõe o semioquímico responsável pela atração do parasitoide H. hebetor, resultando nas primeiras informações de sua estrutura química para sua futura identificação.Kairomones are semiochemicals involved in interspecific interactions of insects that benefit the receiver to the detriment of the emitter. One of these interactions is host searching by parasitoids which detect these compounds as a strategy to locate their hosts. In the case of the larval ectoparasitoid, Habrobracon hebetor Say (Hymenoptera: Braconidae), the \'frass\' of Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) releases a kairomone that attracts females parasitoids. Considering that A. kuehniella has been used for egg production in order to keep natural enemy rearing, this kairomone is undesirable, because it may lead to high H. hebetor infestation and causes important losses during the rearing process. One of the attempts to control these infestations could be the use semiochemical-baited traps. However, as the kairomone is still unidentified, the aim of this work was to isolate it - the first step for its identification. The kairomone was extracted by solvent washing and aeration of A. kuehniella \'frass\'. Then the extracts were tested in a four-way olfactometer with female parasitoids, registering the time taken in each treatment. The active washing extract was fractionated in five fractions in a silica column, and its attractivity was evaluated to proceed to isolation. The extracts and fractions were then analysed by gas chromatography with flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS), in order to locate exclusive compounds in active samples. Furthermore, the fractions from the washed extract were aerated to extract their volatile compounds that were also analysed by GC-MS. The kairomone was isolated in the 75% ether fraction, indicating that it is a polar compound. Comparing the chromatograms, only one peak on the HP-5ms column was selected as belonging to the kairomone. On the Rtx-1ms column, the peak bifurcated, indicating that at least one of the compounds is part of the kairomone. The methodological combinations of this work provided the isolation of the kairomone present in A. kuehniella \'frass\' and the selection of at least one compound that comprises the semiochemical that attracts H. hebetor parasitoid, resulting in the first source of information about its chemical structure for its future identification.
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Viviers, Marlize Zaretha. "Investigation into the semiochemical communication involved in neonatal offspring recognition in sheep." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/3980.
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Thesis (PhD (Chemistry and Polymer Science))--University of Stellenbosch, 2010.Video 1: Twin-bearing Döhne Merino ewe butting only one of her lambs in typical rejection behavior. Rejection of one twin is not a common phenomenon. (Video by Dr Marlize Viviers)
Video 2: Twin-bearing ewe # 22 accepting alien lamb # 179. The alien lamb wears a jacket her other lamb has been wearing for the preceding 24 hours. The excessive sniffing at the jacket, bleating and looking around show that the ewe is not totally satisfied with the situation. (Video by Dr Marlize Viviers)
Video 3: Ewe # 22 rejecting alien lamb # 179 after removal of the jacket it has worn in the previous video. (Video by Dr Marlize Viviers)
ENGLISH ABSTRACT: Sheep husbandry substantially contributes to South Africa’s economy. Lamb mortality is regarded as a major constraint to sustainable sheep production, and an important factor in lamb survival is the strong ewe–lamb bonding. This is a well-known phenomenon in all sheep races and strong evidence exists that the selective ewe–lamb bond formation has a pheromonal basis, in that the ewe can distinguish her lamb by its unique, familiar smell. Sheep farmers and scientists have examined various methods of making alien lambs acceptable to foster ewes. The survival rate of offspring could be substantially increased if a reliable method could be devised to prevent ewes from rejecting their own lambs or if ewes could be induced to accept alien lambs. A better understanding of the semiochemicals involved in this communication between ewe and offspring could facilitate the development of a method by which ewes can be coaxed into adopting foster lambs. This would positively contribute to efficient sheep production in South Africa. The objective of this study was to characterise the volatile constituents present in the wool and the amniotic fluid collected from the Döhne Merino lambs to achieve a better understanding of the ewe–lamb semiochemical communication. The volatile organic constituents associated with the wool and amniotic fluid were characterised and a total of 133 volatile organic compounds were identified. Several compound classes are represented in these samples and the majority of these compounds have previously been identified in the excretions and secretions of numerous mammalian species. A number of different aspects of ewe–lamb kin recognition were investigated. First, the odour profiles of twin lambs were compared to those of other twins. The results of these analyses revealed that the wool volatiles of twin lambs are qualitatively as well as quantitatively practically identical, but different from those of other lambs in the flock. Second, the change in the odour profiles of lambs was studied over a seven-day period. It was found that the odour profiles of lambs are not fixed, and for as long as a ewe makes use of olfactory recognition as the main mode of identification of her lamb she has to continue learning the odour of her lamb. Third, the amniotic fluid was investigated as a possible source of maternal labels, i.e. as chemical codes consisting of mixtures of compounds in specific quantitative ratios that are imprinted on lambs by their mothers at birth. It was found that the amniotic fluids of first- and second-born lambs are qualitatively and quantitatively different. It is possible that the duration of the lambing birth process could contribute to this change in amniotic fluid composition. Fourth, the role of residual proteins in the dissemination of the semiochemicals involved in ewe– lamb communication was investigated and six proteins were identified as amniotic fluid and wool-associated proteins. Bioassays carried out during the lambing season of 2009 confirmed the role of the odour of the lamb in ewe-lamb recognition, but bioassays carried out with synthetic pheromone formulations gave inconclusive results.
AFRIKAANSE OPSOMMING: Skaapboerdery lewer aansienlike bydrae tot die ekonomie van Suid Afrika, maar lamsterftes is een van die kwellende probleme waarmee kleinveeboere te kampe het. Die eksklusiewe band wat binne die eerste paar uur na 'n lam se geboorte tussen die ooi en haar lam ontwikkel, is die hooffaktor waarvan lammers se oorlewing afhang. Hierdie sterk binding tussen lam en ooi is 'n bekende verskynsel in alle skaap-rasse en dit is bekend dat 'n feromoon wat deur die lam vrygestel word, dit vir die ooi moontlik maak om haar lam aan sy unieke reuk uit te ken. Lamsterftes sou aansienlik verminder kon word as hierdie feromoon geïdentifiseer en gebruik kan word om ooie te verhoed om hulle eie lammers te verwerp en om die aanvaarding van vreemde lammers deur ooie moontlik te maak. Die doel van hierdie studie was die chemiese karakterisering van die vlugtige organiese verbindings aanwesig in die amniotiese vloeistof en wol van Döhne Merino lammers ten einde 'n beter begrip van die semiochemiese kommunikasie tussen ooie en lammers te verkry. In die amniotiese vloeistof is 70 vlugtige organiese verbindings geïdentifiseer. Dieselfde verbindings asook 'n verdere 63 verbindings is in lammerwol geïdentifiseer. Die meerderheid van hierdie verbindings is reeds voorheen in verskeie soogdierafskeidings gevind. Die studie het verskeie interessante aspekte van hierdie semiochemiese kommunikasie aan die lig gebring. Eerstens is daar gevind dat die samestelling van die vlugtige organiese materiaal in die wol van tweelinglammers, oftewel hul reukprofiele, feitlik identies is. Verder verskil die reukprofiele van 'n tweeling van dié van ander tweelinge en enkelinge in die trop. Tweedens is gevind dat die reukprofiel van 'n lam nie by geboorte vasgelê word en so behoue bly nie, maar dat dit geleidelik verander oor ten minste die periode van sewe dae waaroor hierdie verskynsel bestudeer is. Dit noodsaak die ooi om haar geheue met betrekking tot die lam se reuk voortdurend te verfris gedurende die tydperk wat sy hoofsaaklik van haar reuksin gebruik maak om haar lam te herken. Derdens is die amniotiese vloeistof ondersoek as moontlike bron van ‘n sogenaamde moedermerk, waardeur chemiese mengsel van verbindings wat in ‘n spesifieke kwantitatiewe samestelling by geboorte deur die ooi op haar lam agter gelaat word. Ten opsigte van kwalitatiewe en kwantitatiewe samestelling, verskil die vlugtige organiese fraksie van die amniotiese vloeistof van die tweelinglam wat eerste gebore word van die amniotiese vloeistof van die lam wat tweede gebore word. Dit is onwaarskynlik dat amniotiese vloeistowwe wat ten opsigte van hul vlugtige organiese fraksies van mekaar verskil, nagenoeg identiese moedermerke op tweeling lammers sou kon laat. Vierdens is vasgestel dat spore van ses proteïene uit die amniotiese vloeistof op die wol van lammers agtergelaat word. Daar kon ongelukkig nie vasgestel word of hierdie proteïene 'n rol in die vrystelling van semiochemiese inligting speel nie. Gedragstoetse wat tydens die lamseisoen van 2009 uitgevoer is, het bevestig dat die lam se reukprofiel deurslaggewende rol in ooi-lam herkenning speel, maar gedragstoetse wat met sintetiese feromoonmengsels uitgevoer is, het onbesliste resultate opgelewer.
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Scott, Gary Terri. "The role of micro-organisms in the production of semiochemicals in the interdigital secretion of the bontebok, Damaliscus pygargus pygargus." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/53774.
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Thesis (MSc)--Stellenbosch University, 2004.ENGLISH ABSTRACT: Bontebok, Damaliscus pygargus pygargus, formerly classified as D. dorcas dorcas, are territorial animals with interdigital glands between the toes of the forelegs. Males regularly defecate on dung heaps, on which they often lie, to communicate with other members of their species. They also communicate by means of visual displays, scent marking and occasionally with scraping or pawing of dung heaps. It is assumed that scent marking with the interdigital secretion serves to define territories frequented by these antelope. These glands secrete a complex mixture of volatile and non-volatile compounds and the volatile compounds in the secretion serve as a chemical signal for other bontebok. It has been suggested that the interdigital secretion is not produced in its final composition by the interdigital gland alone, but that microbial activity is responsible for many of the compounds present in the secretion. In general, many compounds can be attributed to the by-products of microbial hydrolysis of triglycerides, a common characteristic of sebum. It is well documented that micro-organisms inhabit the deep recesses of sebaceous glands and the presence of micro-organisms has been found to be consistent in all antelope exocrine glandular areas. This study involved the chemical characterisation of the volatile metabolites produced in vitro by micro-organisms from the interdigital cavity of the bontebok. Various comparative studies were made, one of which was comparison of the metabolites produced by the individual microbial species as well as the total community of bacteria incubated in different media. A comparison of the compounds identified in the interdigital secretion and the metabolites produced by the micro-organisms in the different media was also made. The volatile metabolite extracts of the individual bacterial species and of the total community were chemically characterised by low-resolution gas chromatography-mass spectroscopy. Classes of compounds identified from the volatile metabolite extracts include: • Acids - Aliphatic (saturated and unsaturated) • Alcohols - Aliphatic (saturated and unsaturated) • Aldehydes - Aliphatic (saturated and unsaturated) • Aromatic compounds • Ketones - Aliphatic (saturated and unsaturated) • Pyrazines • Dimethyldisulphide • Squalene and cholesterol Several qualitative differences were found between the compounds identified in the volatile metabolite extracts of the micro-organisms when incubated in tryptic soy broth (TSB) and minimal salt medium (MSM). In particular, when the microbes were incubated in TSB medium a number of pyrazines were found that were not present when utilising MSM as a medium. Additional qualitative differences were found between the compounds identified in the metabolite extracts of the individual bacterial species and the total community of bacteria, when incubated in both TSB and MSM media. A comparison of the interdigital secretion and the metabolite extracts of the microbial communities incubated in TSB and MSM revealed that many compounds produced in MSM corresponded to the compounds identified in the interdigital secretion. These corresponding compounds were found to be saturated and unsaturated acids, aldehydes and squalene. Furthermore, there was only one corresponding compound in the case of TSB as medium.
AFRIKAANSE OPSOMMING: Die bontebok, Damaliscus pygargus pygargus, voorheen geklassifiseer as D. dorcas dorcas, is 'n territoriale dier met interdigitale kliere tussen die kloutjies van die voorpote. Ramme ontlas gereeld op mishope, waarop hulle dikwels lê, om met ander lede van die spesie te kommunikeer. Hulle kommunikeer ook deur middel van visuele seine, reukmerking en soms deur mishope met die voorpote te kap of te skraap. Reukmerking met die interdigitale afskeiding dien klaarblyklik om gebiede wat deur hierdie diere bewoon word, af te baken. Die interdigitale kliere skei 'n komplekse mengsel van vlugtige en nie-vlugtige verbindings af en die vlugtige verbindings dien as chemiese sein vir ander bontebokke. Die vermoede bestaan dat die interdigitale klier nie alleen verantwoordelik is vir die finale samestelling van die interdigitale afskeiding nie, maar dat mikrobiese aktiwiteit bydra tot die produksie van baie van die verbindings wat in die afskeiding aanwesig is. Sekere verbindings kan in die algemeen toegeskryf word aan die vorming van die neweprodukte van mikrobiese hidrolise van trigliseriede, 'n algemene eienskap van sebum. Dit is bekend dat die diep holtes van vetkliere 'n goeie teelaarde is vir mikroorganismes en daar is gevind dat mikroorganismes feitlik deurgaans voorkom in alle anteloop eksokriene klierareas. Hierdie studie behels die chemiese karakterisering van die vlugtige metaboliete wat in vitro deur mikroorganismes van die interdigitale klierholte van die bontebok geproduseer word. Verskeie vergelykende studies is uitgevoer waarvan een die vergelyking was van die metaboliete wat deur die individuele mikrobiese spesies sowel as die totale gemeenskap van bakterieë geproduseer word tydens inkubasie in verskillende media. Vergelyking van die verbindings wat in die interdigitale afskeiding geïdentifiseer is met die metaboliete wat in verskillende media geproduseer is, het ook deel van die studie uitgemaak. Die vlugtige metaboliet ekstrakte van die individuele bakteriese spesies en van die totale gemeenskap is chemies gekarakteriseer deur middel van laeresolusie gaschromatografie-massaspektrometrie. Die volgende groepe verbindings is onder andere in die vlugtige metaboliet ekstrakte geïdentifiseer: • Sure - Alifaties (versadig en onversadig) • Alkohole - Alifaties (versadig en onversadig) • Aldehiede - Alifaties (versadig en onversadig) • Aromatiese verbindings • Ketone - Alifaties (versadig en onversadig) • Pirasiene • Dimetieldisulfied • Skwaleen en cholesterol Verskeie kwalitatiewe verskille is gevind tussen die verbindings wat geïdentifiseer is in die vlugtige metaboliet ekstrakte van die mikroorganismes onderskeidelik in TSB medium en MSM geïnkubeer. Opvallend was byvoorbeeld die voorkoms van pirasiene in gevalle waar mikroorganismes in TSB medium geïnkubeer is, terwyl hierdie groep verbindings afwesig was wanneer MSM gebruik is. Onderlinge kwalitatiewe verskille is ook gevind tussen die verbindings wat geïdentifiseer is in die metaboliet ekstrakte van die individuele bakteriese spesies en die totale gemeenskap van bakterieë, wanneer in TSB medium sowel as in MSM geïnkubeer is. Vergelyking van die verbindings in die interdigitale afskeiding en in die metaboliet ekstrakte van die mikrobiese gemeenskappe, het getoon dat 'n aantal verbindings wat in MSM geproduseer is, ooreenstem met verbindings wat in die interdigitale afskeiding geïdentifiseer is. Daar is gevind dat hierdie verbindings versadigde en onversadigde sure en aldehiede en skwaleen is. Met TSB as medium was daar slegs een ooreenstemmende verbinding.
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Silva, Weliton Dias da. "Comportamento sexual da broca-do-café, Hypothenemus hampei (Ferrari, 1867) (Coleoptera: Curculionidae: Scolytinae)." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-17032010-141611/.
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O estudo do comportamento sexual dos insetos abrange todos os eventos ocorridos desde a formação dos casais por meio do cortejo, até a separação dos mesmos após a cópula. Esses estudos são importantes e representam o primeiro passo em pesquisas que visam à elucidação de feromônios da espécie alvo. No caso da broca-do-café, Hypothenemus hampei (Ferrari), que é considerada mundialmente a principal praga do café, existe uma lacuna de informações sobre o comportamento sexual dessa espécie. Além disso, as pesquisas têm sido direcionadas para o uso de armadilhas contendo alcoóis (ex: etanol e metanol) visando o manejo dessa praga, mas com resultados conflitantes. Em razão disso, o objetivo do presente trabalho foi estudar o comportamento sexual de H. hampei, como suporte para estudos subseqüentes visando a elucidação do feromônio da espécie. As cópulas de H. hampei ocorreram em qualquer horário dentro de um ciclo de 24 horas. Embora em menor freqüência, 60% dos casais realizaram pelo menos uma cópula na idade de 0-24 horas, chegando a 100% dos casais nas demais idades. A maior atividade sexual foi observada nas idades de 48-72 e 72-96 horas, onde, nessa última, ocorreram 6,9 ± 0,47 cópulas por casal com duração de 2,04 ± 0,13 minutos cada. Os padrões comportamentais exibidos foram semelhantes a outros grupos de curculionídeos, com pré-cópula, cópula e pós-cópula. Os resultados indicaram ainda a presença de um feromônio produzido pelos machos mediando o acasalamento. A possibilidade de as fêmeas de H. hampei realizarem a recópula após sua saída dos frutos abre novas perspectivas sobre a viabilidade deste feromônio no manejo desta praga.The sexual behavior study in insects includes all the events occurred since of pair encounter by means of courtship until their separation after mating. These studies are important and represent the first step of researches that aim to elucidate pheromones of target species. Regarding the coffee berry borer, Hypothenemus hampei (Ferrari), which is the most important coffee pest around the world, little is known about its sexual behavior. Furthermore, the researchers have been focused on the use of traps based on alcohols (e.g. ethanol and methanol) with aims of managing this pest, but its results are conflicting. For that reason, the aim of the present work was to study the sexual behavior of H. hampei, whose it will give support to subsequent studies about evaluation of pheromone this species. Daily mating rhythm of H. hampei occurred on any time of 24- hour cycle. Although at low rates, 60% of paired adults mated at least once when they were 0-24 hours, reaching 100% in older pairs. The highest sexual activity was observed in the ages of 48-72 and 72-96 hours, being in this last one the occurrence of 6,9 ± 0,47 matings/pair with a mean duration of 2,04 ± 0,13 minutes each. The pattern behavior displayed was similar to other groups of Curculionidae, with premating, mating and postmating. The results also indicated the presence of a pheromone produced by the males that mediates mating. The possibility of the H. hampei females recopulates after they leave the fruits opens new perspectives to investigate the viability of using this pheromone in management of this pest.
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Page, Jennifer Lynn. "The effects of plume property variation on odor plume navigation in turbulent boundary layer flows." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29752.
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Thesis (Ph.D)--Biology, Georgia Institute of Technology, 2009.Committee Chair: Weissburg, Marc; Committee Member: Hay, Mark; Committee Member: Kubanek, Julia; Committee Member: Webster, Donald; Committee Member: Yen, Jeannette. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Peck, Gavin Earl. "Potential Semiochemicals of Wheat (Triticum aestivum L.) Induced by Oviposition and Feeding of the Wheat Stem Sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae)." Thesis, Montana State University, 2004. http://etd.lib.montana.edu/etd/2004/peck/PeckG1204.pdf.
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Cephus cinctus Norton (Hymenoptera: Cephidae), the wheat stem sawfly, is currently the most devastating insect pest of wheat production in Montana. Currently, no effective controls are in place to check its damage and spread throughout wheat fields in the northern Great Plains. Natural biological control of sawflies occurs primarily in the form of larval parasitoids which attack the sawfly larva in the stem; however, these parasitoids are not reliably effective in controlling sawfly populations. Insect damage induces chemical changes in plants, and often these changes are part of a defensive response to the insect injury. Some of these chemical changes are apparent in the volatile chemicals produced by the plants and may include semiochemicals used by sawflies and parasitoids. Identifying the changes in volatile production could enhance the understanding of sawfly-wheat plant-parasitoid interactions and lead to more effective control measures for the wheat stem sawfly. I investigated the differences in the volatile chemicals produced by sawfly-infested and uninfested wheat plants and endeavored to determine if those differences were qualitative or quantitative. Additionally, I wanted to determine if changes in volatile production induced by the wheat stem sawfly could be mimicked by wounding coupled with the application of sawfly cuticular wax to wheat stems or by the injection of frass-treated water into the internodes of wheat stems. Volatiles of infested and uninfested wheat plants were collected and compared, with the results indicating that sawfly damage induces quantitative changes in some volatile chemicals produced by wheat. These results are discussed regarding their context within sawfly-wheat plant-parasitoid interactions and implications for better sawfly control. Volatiles from sawfly-infested, uninfested, frass-water-injected, and pin-pricked/waxtreated plants were also collected, and differences in 11 compounds selected from the results of the 1st experiment were compared. The results of this experiment found that pin-pricked/wax-treated plants came closer to mimicking the volatile production changes induced by sawfly infestation, but neither frass-water injection nor pin-pricked/cuticular wax application reliably induced the same changes in wheat volatiles that sawfly infestation did. There was, however, a definite response of the wheat to the application of the sawfly cuticular wax, and its significance is discussed.
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Zhang, Qing-He. "Olfactory recognition and behavioural avoidance of angiosperm non-host volatiles by conifer bark beetles /." Alnarp : Swedish Univ. of Agricultural Sciences (Sveriges lntbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-5789-0.pdf.
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Moura, Jose Inacio Lacerda. "Polinização de dendezeiro por Elaeidobius subvittatus Faust e Elaeidobius kamerunicus Faust (Coleoptera, Curculionidae) no sul do Estado da Bahia /." Jaboticabal : [s.n.], 2008. http://hdl.handle.net/11449/102289.
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Orientador: Francisco Jorge CividanesBanca: Antonio Carlos Busoli
Banca: José Maurício Simões Bento
Banca: Júlio César Galli
Banca: César Freire Carvalho
Resumo: Este foi conduzido no sul do estado da Bahia entre os anos de 2004 e 2007. Teve como objetivo determinar a taxa de fecundação de dendezeiros após a introdução de Elaeidobius kamerunicus Faust . Avaliaram-se as relações das espécies E. kamerunicus e Elaeidobius subvittatus Faust através da: flutuação populacional, distribuição espacial, influência de fatores meteorológicos, comportamento com relação às inflorescências das plantas e capacidade de transportar grãos de pólen. A taxa de fecundação nos dendezeiros atingiu 79,4%, representando incremento de 19% quando comparado aos dendezeiros polinizados apenas por E. subvittatus. Plantios comerciais de dendezeiros nos municípios de Taperoá e Nazaré, mostraram taxas de fecundação de 76,8% e 78,0%, respectivamente. E. kamerunicus foi a espécie dominante nos plantios de dendezeiro de Una, BA. Com exceção do município de Itapebi, as populações de E. kamerunicus sobrepujaram as de E. subvittatus em todos os municípios com grandes maciços de dendezeiros subespontâneos. A distribuição das chuvas no sul da Bahia não alterou a atividade polinizadora de E. kamerunicus, permitindo ocorrer taxa constante de fecundação dos frutos. Houve aumento da densidade populacional de E. subvittatus com o incremento térmico no ambiente ocorrendo o oposto com E. kamerunicus. O número de espécimes de E. subvittatus visitando inflorescências femininas de dendezeiros e híbridos interespecíficos foi superior ao de E. kamerunicus entre 6:00 e 8:00 horas, porém E. kamerunicus foi mais numeroso que E. subvittatus entre 9:00 e 12:00 horas. Essas espécies apresentaram pouca atividade polinizadora nas inflorescências femininas entre 14:00 e 16:00 horas, mas E. subvittatus congregou-se nas inflorescências femininas de ambas variedades de plantas a partir de 16:00 horas. Ao anoitecer foi constatada a presença... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The study was conducted in south Bahia between 2004 and 2007 to determine the rate of fertilization of oil palm after the introduction of Elaeidobius kamerunicus Faust in Southern Bahia. Relationships of the species E. kamerunicus and Elaeidobius subvittatus Faust were evaluated through population fluctuation, spatial distribution, influence of meteorological factors, behavior regarding the plant inflorescences and capability to collect and transport pollen grains. The data were analyzed utilizing correlation and variance analysis and test of means. The rate of fertilization in the oil palm trees reached 79.4%, representing an increase of 19% when compared to oil palm trees pollinated only by E. subvittatus. Commercial plantations of oil palm trees in Taperoá and Nazareth municipalities showed rates of fertilization of 76.8% and 78.0%, respectively. E. kamerunicus was the dominant species in the plantations of oil palm trees of Una, BA. With the exception of Itapebi municipality, the populations of E. kamerunicus overwhelmed the E. subvittatus in all municipalities with large plantations of sub-spontaneous oil palm trees. The rainfall distribution in south Bahia did not alter the pollination activity of E. kamerunicus, which permitted a constant rate of fruit fertilization. There was an increase in population density of E. subvittatus with environmental thermal increase, the opposite occurred with E. kamerunicus. The number of specimens of E. subvittatus visiting female inflorescences of oil palm trees and interspecific hybrids was higher than that of E. kamerunicus between 6:00 and 8:00 hours, however E. kamerunicus was more numerous than E. subvittatus between 9:00 and 12:00 hours. These species presented little pollination activity in female inflorescences between 14:00 and 16:00 hours, but E. subvittatus congregated in the female inflorescences of both oil palm varieties starting ...(Complete abstract click electronic access below)
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Brandl, Michael Albert [Verfasser], Stefan [Akademischer Betreuer] [Gutachter] Vidal, Anant [Gutachter] Patel, and Stefan [Gutachter] Schütz. "Exploitation of synergistic effects between semiochemicals and Metarhizium brunneum against soil pests / Michael Albert Brandl. Betreuer: Stefan Vidal. Gutachter: Stefan Vidal ; Anant Patel ; Stefan Schütz." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2016. http://d-nb.info/1112325344/34.
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Späthe, Anna Maria [Verfasser], Bill S. [Akademischer Betreuer] Hansson, Peter [Akademischer Betreuer] Anderson, and Sylvia [Akademischer Betreuer] Anton. "The function of volatile semiochemicals in host plant choice of ovipositing manduca moths (sphingidae) / Anna Maria Späthe. Gutachter: Bill S. Hansson ; Peter Anderson ; Sylvia Anton." Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2014. http://d-nb.info/1047097079/34.
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Zazycki, Luiza Cristiane Fialho. "Variabilidade do feromônio sexual de diferentes populações brasileiras de Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae)." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-25062014-100343/.
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S. frugiperda é uma praga chave no cultivo de milho. A espécie é polífaga e apresenta variações intraespecíficas, sendo caracterizada em dois grupos em função do seu hospedeiro - raça \'Milho\' e raça \'Arroz\' - onde indivíduos morfologicamente idênticos apresentam cargas genéticas distintas. Essas variações podem ser observadas na formação de subgrupos, os quais podem ser compostos por indivíduos geograficamente distintos ou pela forma como se distribuem dentro das populações refletindo diretamente nos padrões de acasalamento da espécie. Em razão disso, este trabalho teve por objetivo compreender a variabilidade genética de populações brasileiras de S. frugiperda e como ela está associada com a produção de diferentes compostos feromonais ou à variação na taxa desses compostos. Para tal, foram coletadas lagartas de S. frugiperda em 6 localidades brasileiras (Santo Augusto-RS, São Raimundo das Mangabeiras-MA, Dourados-MS, Sinop-MT, Assis-SP, e Santa Helena de Goiás-GO). As populações foram avaliadas quanto a sua diversidade genética, perfil cromatográfico das repostas em eletroantenografia (CG-EAG), produção do feromônio e respostas comportamentais em túnel de vento. Os resultados demonstraram uma frequência variável entre as raças de \'Milho\' e \'Arroz\' nas populações brasileiras de S. frugiperda de acordo com o local e época de amostragem. Foram constatados um elevado número de haplótipos nas populações brasileiras, e aparentemente, isto foi resultado da presença de um alta diversidade haplotípica e das pressões do ambiente. Os machos de S. frugiperda responderam para até 4 compostos químicos presentes nas amostras de feromônio sexual e houve uma diferença na abundância do composto majoritário, o acetato de (Z)-9 Tetradecenila, entre as populações das diferentes localidades avaliadas. Em túnel de vento, os machos apresentaram diferentes níveis de atração para as fêmeas de S. frugiperda tanto para uma mesma localidade quanto para localidades distintas.S. frugiperda is a key pest in corn cultivation. This species is polyphagous and has intraspecific variation, which can be distinguished into two groups according to their host - races \'Corn\' and \'Rice\'. Individuals of both races are morphologically identical, but have distinct genetic loads. These variations can be observed in subgroups formation, which may consist of geographically distinct individuals or by the way they are distributed within populations reflecting directly on mating patterns of the species. For this reason, this work aims at understanding the genetic variability of Brazilian populations of S. frugiperda and how it is associated with the production of different pheromonal compounds or the variation in the rate of these compounds. For this, fall armyworms were collected at 6 locations in Brazil (Santo Augusto-RS, São Raimundo das Mangabeiras-MA, Dourados-MS, Sinop-MT, Assis-SP, and Santa Helena de Goiás-GO). The populations were evaluated for genetic diversity, chromatographic profile of the responses in electroantennography (GC-EAD), pheromone production and behavioral responses in a wind tunnel. Results showed a variable frequency between races \'Corn\' and \'Rice\' in Brazilian populations of S. frugiperda according to the locality and period of sampling. A large number of haplotypes in Brazilian populations were identified, and apparently, this is caused by the presence of a haplotype diversity and environmental selection pressure. Males of S. frugiperda responded to up to 4 chemical compounds from samples of sex pheromone and there was a difference in the abundance of the major compound, the acetate (Z)-9 Tetradecenila between populations of different localities evaluated. In the wind tunnel, males showed different levels of attraction to females of S. frugiperda to both the same site and for different site.
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Tonelli, Mateus. "Resposta de nematoides entomopatogênicos aos voláteis radiculares de cana-de-açúcar (Saccharum officinarum L.) sob herbivoria de ninfas de Mahanarva fimbriolata (Stål) (Hemiptera: Cercopidae)." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-13032015-083636/.
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As respostas dos nematoides entomopatogênicos, Steinernema carpocapsae (Weiser) e Heterorhabditis indica (Poinar, Jackson e Klein), aos voláteis emitidos por raízes de cana-de-açúcar (Saccharum officinarum L.) danificadas ou não danificadas por ninfas da cigarrinha-da-raiz, Mahanarva fimbriolata (Stål), foram estudadas em laboratório. Plantas de cana-de-açúcar foram transplantadas para câmaras laterais do olfatômetro de seis vias e submetidas ou não a herbivoria por M. fimbriolata. Cerca de 10000 nematoides entomopatogênicos foram liberados na câmara central do olfatômetro e após 24 horas os nematoides foram contabilizados em cada câmara lateral do dispositivo. Raízes de plantas previamente danificadas ou não danificadas por M. fimbriolata foram destacadas das plantas, congeladas com nitrogênio liquido e maceradas. O material foi então aerado por 8 horas para a coleta dos voláteis. O perfil dos voláteis dos extratos naturais foi analisado em um cromatógrafo gasoso acoplado a um espectrômetro de massas (GC-MS). Os nematoides de ambas as espécies foram atraídos pelos voláteis radiculares de plantas danificadas pela cigarrinha-das-raízes, em contraste com plantas não danificadas e areia umedecida (controle). As análises em GC-MS revelaram que não houve diferença qualitativa no perfil de voláteis radiculares entre os tratamentos. Por outro lado, dos 11 compostos presentes nas raízes não danificadas, di-hidro mircenol e Beta isso metioneno reduziram, significativamente, sua concentração após o ataque de M. fimbriolata. Estes resultados sugerem que o recrutamento de nematoides entomopatogênicos neste sistema pode ter sido influenciado pela diminuição da concentração destes dois compostos radiculares nas plantas sob herbivoria.The responses of entomopathogenic nematodes Steinernema carpocapsae (Weiser) and Heterorhabditis indica (Poinar, Jackson e Klein), to volatiles emitted by sugar cane roots damaged or undamaged by Mahanarva fimbriolata (Stål) nymphs, were investigated under laboratory conditions. Thus, sugarcane plants damaged or undamaged by M. fimbriolata were transplanted to lateral arms of six arm olfactometer. Approximately 10000 entomopathogenic nematodes were released in the central chamber of the olfactometer and after 24 hours, the nematodes were counted in each arm. Roots of previously damaged or undamaged plants were detached, frozen with liquid nitrogen and macerated. The material was then aerated for 8 hours to collect volatiles. The volatiles profile was analyzed by a gas chromatograph-mass spectrometer. Most nematodes of both species moved to plants that had been previously damaged over undamaged plants, and there was no significant difference in the choice of undamaged plant and only moisted sand. The GC-MS analyzes showed no qualitative difference between the root treatments volatiles profile. In both treatments, the same 11 compounds were found. Although, two compounds, dihydro myrcenol and Beta-iso-methionene, showed quantitative difference between treatments, observing greater production in undamaged plants, i.e. herbivory caused reduction in tested sugar cane roots volatiles releasing. These data provide new information about the tritrophic relationships occurring in the soil which, in the future, can be used in order to develop field management for M. fimbriolata.
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Bång, Joakim. "Purification, Stereoisomeric Analysis and Quantification of Biologically Active Compounds in Extracts from Pine Sawflies, African Butterflies and Orchid Bees." Doctoral thesis, Mittuniversitetet, Institutionen för naturvetenskap, teknik och matematik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-14662.
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Stereochemistry plays an important role in nature because biologically important molecules such as amino acids, nucleotides and sugars, only exist in enantiomerically pure forms. Semiochemicals carry messages, between the same species (pheromones) and between different species (allelochemicals). Both pheromones and allelochemicals can be used as environmentally friendly pest management. Many semiochemicals, i.e. behaviour modifying chemicals, consist of pure or well-defined mixtures of stereoisomers, where some of the other stereoisomers can be repellent. It is therefore important to be able to separate them to produce a synthetic pheromone in a mixture that is attractive. Pine sawflies are a family of insects that in some cases can be severe defoliators of conifer trees. Diprion pini, Diprion similis and Neodiprion sertifer are severe pests for these trees and have got the most attention in pine sawfly pheromone studies. The pheromone precursors are stored in the female body as long-chain secondary alcohols, which, when released, are esterified to acetates or propionates. The alcohols are chiral, and normally one of the stereoisomer is the main pheromone component, sometimes possible together with other stereoisomers as essential minor components. Bicyclus is a genus of African butterflies, and especially Bicyclus anynana has become a popular model for the study of life history evolution, morphology, mating choice and genetics. The wing pattern of Bicyclus differs depending on the season, with large eyespots during the rain-season and small or absent spots during the dry season. Euglossa is one of the genera among the orchid bees in the Neotropics that does not produce its own pheromone. Instead, the males collect fragrances from orchids and other sources and store them in a pocket in their hind legs. Both Bicyclus and Euglossa use semiochemicals similar to pine sawflies, and thus can be analysed by the same methods. Pheromones and other semiochemicals in insects are often present in low amounts in a complex matrix, and purification of the sample before chemical analysis is often required. A common method is gradient elution on a solid phase silica column. Separation of stereoisomers can be achieved either by using a column with a chiral stationary phase (CSP) or with pre-column derivatisation using a column with an achiral stationary phase (ASP) or a combination of both, with mass detection as the dominant detection method. The purpose of this work has been to improve the purification method, find suitable methods to separate the stereoisomers of secondary alcohols, and to apply this on extracts of insects. By selecting the right fractions to collect during gradient elution the purification method was optimised. To reduce plasticizer contamination from ordinary columns, solid phase columns of Teflon or glass were used. For pre-column derivatisation of different chiral alcohols various acid chlorides were tested. For the pine sawfly pheromone precursors enantiopure (2S)-2-acetoxypropionyl chloride was the best choice. To separate some of the stereoisomers achiral 2-naphthoyl chloride was used. For derivatisation of 6,10,14-trimethylpentadecan-2-ol (R)-trans-chrysanthemoyl chloride was the best choice. The derivatised alcohols were separated on different columns, both chiral and non-chiral. Varian FactorFour VF-23ms was chosen as a general-purpose column, the Agilent HP-88 column was the best column with an ASP of those tested, and the Chiraldex B-PA column (CSP) was the only one that could separate all eight stereoisomers of derivatised 3,7-dimethylundecan-2-ol, 3,7-dimethyldodecan-2-ol, and 3,7-dimethyltridecan-2-ol. To determine the stereoisomeric purity of standard solutions used in field experiments and extracts of different species of insects the optimised methods were applied. For extracts from B. anynana, Euglossa and Neodiprion lecontei this work describe the first determination of the stereochemistry of some of their semiochemicals. For the determination of the stereochemistry of chiral semiochemicals the methods for purification and separation presented herein have shown to be of great value. The results will hopefully contribute to a better understanding of the communication among insects, and ultimately to a more environmentally friendly pest control.Många naturligt förekommande kemiska ämnen finns som två spegelbilder av varandra, ungefär som höger och vänster hand. Dessa kan ha helt olika egenskaper och det är därför viktigt att kunna separera dem. Insekter och andra djur använder olika doftämnen för att kommunicera med varandra, om det är inom samma art kallas de för feromoner. De kan bestå av ett ämne eller en blandning av flera. Dessa doftämnen kan man även använda för att på ett miljövänligt sätt bekämpa skadeinsekter. En fälla med syntetiskt feromon för en viss insekt lockar endast till sig den arten, medan alla andra är opåverkade. Eftersom dessa ämnen ofta finns som spegelbilder där kanske bara den ena är aktiv och den andra rent av frånstötande, måste man kunna separera dem för att framställa ett syntetiskt feromon som är attraktivt. Målet med detta arbete har varit att bestämma feromonet hos olika arter av tallsteklar som kan vara svåra skadedjur på tallskog. De metoder som tagits fram har även tillämpats på några arter av afrikanska fjärilar samt orkidébin från Centralamerika eftersom de använder snarlika doftämnen. Att få fram feromonet från en insekt är lite som att leta efter in nål i en höstack eftersom de ofta bara innehåller några miljarddels gram per individ. Provet behöver först renas, och en del av arbetet i det här projektet har gått ut på att ta fram en lämplig reningsmetod. Huvudfokus har dock varit på att ta fram metoder som kan separera och identifiera det eller de ämnen, och spegelbilder av dessa, som doftämnena består av. När lämpliga metoder tagits fram har extrakt av olika insektsarter analyserats. I några fall är det första gången som deras feromon bestämts i detalj. Resultaten kan förhoppningsvis bidra till en ökad kunskap om insekters sätt att kommunicera, och i slutändan till miljövänligare bekämpning av skadeinsekter.
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Silva, Weliton Dias da. "Idade de fêmeas colonizadoras de Hypothenemus hampei (Ferrari) e sua resposta aos voláteis de flores de café, Coffea arabica L." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-02062014-114207/.
Full textAbstract:
A idade das fêmeas colonizadoras de Hypothenemus hampei (Ferrari) durante o abandonamento do hospedeiro, assim como sua resposta aos voláteis de flores de café, Coffea arabica L. var. Tupi, foram investigadas neste trabalho. Um dispositivo experimental que simulasse as condições de dentro do fruto de café e permitisse a observação da saída dos insetos foi utilizado para a determinação da idade das fêmeas colonizadoras. Em média, os besouros apresentaram 15 dias de idade no momento em que abandonaram o dispositivo experimental. Nesta idade as fêmeas estavam acasaladas, possuiam o tegumento totalmente melanizado, foram capazes de voar e produzir ovos viáveis. Os voláteis de flores de café, foram coletados por aeração, analisados por GC-EAD e GC-MS, e testados em bioensaios olfatométricos. As fêmeas colonizadoras de H. hampei foram atraídas pelos voláteis de flores de café. Dos 50 compostos encontrados nos extratos naturais, sete foram eletrofisiologicamente ativos aos insetos. Destes sete, somente metil salicilato, neral e geranial puderam ser identificados, e a mistura de seus padrões sintéticos foi a mais atrativa nos bioensaios olfatométricos. Tomados juntos, estes resultados trazem novas informações sobre a bioecologia e ecologia química da broca-do-café, as quais poderão ser usadas futuramente em pesquisas de base e naquelas focadas no desenvolvimento de novas estratégias de manejo para H. hampei em cafezais.The age of Hypothenemus hampei (Ferrari) females during the host abandonment, as well as their response to coffee flower volatiles were determinated under laboratory conditions. A experimental device that simulated the conditions inside a coffee berry, and that allowed the observation the insects coming out was used to determinate the age of colonizing females. On average, the beetles were 15 d-old at the moment they abandoned the experimental device. In this age, the females were mated, had a fully melanized tegument, were able to fly and to produce viable eggs. The volatiles of coffee, Coffea arabica L. var. Tupi, flowers were colected by aeration, analyzed in GC-EAD and GC-MS, and tested in olfactometer bioassays. The colonizing H. hampei females were attracted by the coffee flower volatiles. Of 50 compounds found in the natural extracts, seven were electrophysiologically actives to the insects. Of these seven, only methyl salicylate, neral and geranial could be identified, and the blend with their syntetic standards was the most atractive in the olfactometer bioassays. Taken together, these results bring new information on the bioecology and chemical ecology of the coffee berry borer, which may be used in the future by basic researchs or by those focused on the development of new strategies for the management of H. hampei in coffee farms.
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Wallin, Erika. "The Scents of Nature : Identification and Synthesis of Bioactive Compounds Used in Insect Communication." Doctoral thesis, Mittuniversitetet, Avdelningen för kemiteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-22821.
Full textAbstract:
Pest insects cause great financial losses in the forest and food industry every year. To fight these pests industries have used insecticides, which are sometimes harmful to nature and humans. One potential way of avoiding insecticides is the use of integrated pest management based on insect communication, which would offer species-specific methods for protecting forest and food resources. Insects use chemicals known as semiochemicals for both intra- and interspecies communication. By learning how insects use these semio-chemicals to talk to each other we can eavesdrop and mimic their communication for our benefit. One research area dealing with these questions is chemical ecology, which is an interdisciplinary area as knowledge in chemistry and biology is required. Collaborations between groups within and outside of Sweden are essential in order to make progress in this field of research. This thesis presents the identification and synthesis of semiochemicals from several insect species, most of which are considered to be pests. Synthesised compounds have been sent to collaboration partners around Sweden and Europe for biological evaluations. Studies of the African butterfly, Bicyclus anynana, have unravelled particular biological phenomena that may aid in the understanding of the Bicyclus genus, though recognizing individual species variation is crucial. In 2008 the putative male sex pheromone of B. anynana was determined to consist of three compounds: hexadecanal, (Z)-9-tetradecenol and 6,10,14-trimethylpentadecan-2-ol, and the specific stereoisomer for 6,10,14-trimethylpentadecan-2-ol has been determined in this thesis. The ratio of 6,10,14-trimethylpentadecan-2-ol and the corresponding ketone were investigated for seventeen Bicyclus species (including B. anynana) that live in overlapping regions in Africa. The stereochemistry was determined for most of the species and may provide a way to chemically distinguish them. The orchid bees, Euglossa spp, are important pollinators of many orchids in Central America. Insight about pollination and conservation of endangered orchid species may be possible by gathering more information about the Euglossa genus. Males of the Euglossa genus have pouch-like structures on their hind legs where they store compounds collected from their surroundings. 6,10,14-Trimethyl-pentadecan-2-one is a common component of leg extracts from Euglossa imperialis, E. crassipunctata and E. allosticta, the specific stereochemistry of which has been determined in this thesis. Another, different compound was found in high amounts in E. viridissima and its structure has been elucidated; several synthetic pathways are under investigation to obtain the target compound. Bed bugs (Cimex lectularius and C. hemipterus) are an ectoparasite that feed on human blood, and the number of reported infestations of these parasites has increased considerably during the last decade. Two 5th instar nymph-specific compounds, 4-oxo-hexenal and 4-oxo-octenal, were identified and synthesised. Utilizing domestic dogs (Canis lupus familiaris) in the identification of bed bug infestations has become popular during recent years. Their training is usually conducted using live bed bugs, however this thesis describes an alternative method of teaching dogs to find infestations. This alternative method is based on synthetic compounds and dogs trained in this manner have achieved a high positive indication rate. Two species of the tiny, Acacia leaf-eating insect pests in Australia known as thrips, Kladothrips nicolsoni and K. rugosus, have been investigated by means of larval extracts and have been shown to contain large amount of (Z)-3-dodecenoic acid which was synthesised and tested in bioassays. Fruit flies are common pests on fruit in almost every private household. Even though fruit flies has been investigated extensively, their chemical communication has not been completely elucidated. (Z)-4-undecenal was identified as a compound emitted by females, it was synthesised in high stereoisomeric purity and evaluated in biological assays.FORE
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Bursztyka, Piotr. "Etude du rôle des sémiochimiques dans les stratégies d'évitement des prédateurs chez deux gastéropodes terrestres : Deroceras reticulatum (Muller, 1774) et xeropicta derbentina (Krynicki, 1836)." Thesis, Toulouse, INPT, 2015. http://www.theses.fr/2015INPT0139/document.
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Malgré des inconvénients rédhibitoires, l’utilisation de molluscicides reste prédominante dans les stratégies de lutte contre les gastéropodes terrestres, une situation qui appelle au développement d’alternatives. Bien que les gastéropodes terrestres reposent essentiellement sur la chémodétection pour la réalisation d’un grand nombre d’interactions capitales avec leur environnement, leur perception de la prédation reste largement méconnue malgré son importance écologique. Nous avons donc étudié l’altération de comportements de maintenance chez deux espèces de gastéropodes terrestres nuisibles, la limace Deroceras reticulatum et l’escargot Xeropicta derbentina, en présence de composés chimiques issus de différentes espèces de carabes, une catégorie importante de prédateurs mallacophages. Les résultats obtenus indiquent que les caractéristiques écologiques des prédateurs sont cruciales dans la perception de la pertinence de la menace par ces gastéropodesDespite crippling drawbacks, molluscicides remain predominant in strategies employed against terrestrial gastropods pests, a situation that call for the development of alternatives. Although chemodetection drive many crucial interactions in terrestrial gastropods, their perception of predation remains largely unknown despite its ecological importance. We investigated the alteration of self-maintenance behaviours of two harmful land gastropods, the slug Derocers reticulatum and the snail Xeropicta derbentina, exposed to chemical compounds from different ground beetle species, an important category of gastropod predators. The results obtained indicate that the ecological features of the predators are crucial for the perception of the relevance of the predation threat by these gastropods
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Lindh, Jenny. "Identification of bacteria associated with malaria mosquitoes - Their characterisation and potential use." Doctoral thesis, Stockholm : Department of Genetics, Microbiology and Toxicology, Stockholm University, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-6685.
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Galvão, André Luiz Beserra. "Avaliação da diversidade genética, prospecção de cairomônios e formulações de sordidina como alternativas ao controle do Cosmopolites sordidus (Germar, 1824) (Coleoptera: Curculionidae)." Universidade Federal de Alagoas, 2014. http://www.repositorio.ufal.br/handle/riufal/1922.
Full textAbstract:
The banana has become of great importance in the world, being directly linked to social and economic relevance, generating income for both family and corporate agriculture. The C. sordidus is a key pest of banana, reducing yields by up to 90%. Therefore, the aim of this study was to evaluate the genetic
diversity of C. sordidus, prospect molecules kairomones and test the location of traps and synthetic pheromone formulations for integrated field management. This work was carried out through institutional partnership between the Federal University of Alagoas LPqRN, Chemistry LTDA Interacta and Farm-Cooperative Bonsucesso Pindorama.In the first study genetic variability was detected intra
and inter-population for this insect among three studied populations originated from regions of banana producers in the state of Alagoas. This result indicates the feasibility studies for exploring the possible variability in proteomic and metabolomic diversity in populations, especially related to communication
insect/insect and insect/plant chemical systems. In the second study, was detected variation in the chemical profile of the volatile atmosphere, the rhizome and pseudostem. Metabolites with functionality in insect/plant interaction and potential application as kairomones for management of C. sordidus were
observed. Among these α-pinene, β-pinene,α-copaene, eukaliptol and limonene. In the third stage, the experiment evaluated trap locations in the field installing these on the edge of the field, and internal traps are recommended in order to enhance the control and monitoring of the arthropod population. In the final study, which evaluated the formulation of pheromone was observed greater efficiency in relation to the amount of sordidina versus capture C.sordidus with 78.06 mg of this semiochemical. However, this efficiency was promoted when associated with mineral oil adjuvant dose 100.8 μL and isoamyl acetate kairomone in the amount of 700 ul per trap.A banana apresenta-se de grande importância no mundo, estando diretamente ligada a relevância social e econômica, geradora de renda tanto para a agricultura familiar quanto empresarial. O C. sordidus é praga chave da cultura da banana, reduzindo a produção em até 90%.Portanto, o objetivo deste trabalho foi avaliar a diversidade genética de C. sordidus, prospectar moléculas de cairomônios e testar local de instalação de armadilhas e formulações sintéticas com feromônio para o manejo integrado deste artrópode em campo.O presente trabalho foi realizado por meio de parceria institucional entre a Universidade Federal de Alagoas LPqRN, a Interacta Química LTDA e a Fazenda Bonsucesso-Cooperativa Pindorama. No primeiro estudo foi detectada variabilidade genética intra e inter-populacional para esse coleóptero entre as três populações estudadas oriundas de regiões produtores de banana no estado de Alagoas. Este resultado indica viabilidade de estudos para prospectar a possível variabilidade na diversidade proteômica e metabolômica nas populações, em especial a relacionada aos sistemas de comunicação química inseto/inseto e inseto/planta.No segundo estudo, detectou-se variação no perfil químico de voláteis da atmosfera, do rizoma e do pseudocaule. Foram observados metabolitos com funcionalidade na interação inseto/planta e potencial aplicação como cairomônios para manejo do C. sordidus.Dentre esses o α-pineno, β-pineno,α-copaeno, eucaliptol e limoneno.Na terceira etapa, ao avaliar o experimento entre locais de instalação das armadilhas em campo recomenda-se a instalação destas na borda do talhão além das armadilhas internas a fim de potencializar o controle e o monitoramento da população do artrópode. No estudo final, onde foi avaliada a formulação do feromônio observou-se maior eficiência em relação à quantidade de sordidina versus captura do C. sordidus com 78,06mg deste semioquímico. Porém, essa eficiência foi promovida quando associada aos adjuvantes óleo mineral na dose 100,8μL e cairomônio acetato de isoamila na quantidade de 700 μL por isca.
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Grau, Paricio Carlos. "Influence of predator and food chemical cues in the behaviour of the house mouse (Mus musculus)." Thesis, Toulouse, INPT, 2019. http://www.theses.fr/2019INPT0068/document.
Full textAbstract:
Les rongeurs commensaux sont responsables de grands dommages en agriculture et dans les zones urbaines. En tant qu’espèces invasives, elles peuvent mettre en danger les espèces locales et sont porteurs et vecteurs de plusieurs zoonoses importantes. Les méthodes de contrôle sont basées principalement sur l’utilisation des warfarines, lesquelles produisent un grand nombre d’intoxications sur des espèces non ciblées et ont perdu une partie de leur efficacité à cause des résistances génétiques constatées chez les espèces cibles. De plus, ces méthodes sont considérées comme inhumaines parce qu’elles causent une mort lente et douloureuse par hémorragies. L’olfaction est une source principale d’évaluation des risques présents dans l’environnement pour les rongeurs, avec la perception des signaux chimiques des prédateurs ou signaux de toxicité des plants/nourriture. Cette perception olfactive peut être utilisé pour modifier l’utilisation de l’espace des rongeurs. L’objectif de cette thèse était l’identification des réponses comportementales aux messages chimiques importants (par exemple les signaux chimiques émis par les plantes et les prédateurs) dans l’écologie de la souris domestique (Mus musculus), avec l’utilisation de souches de laboratoire comme modèle des animaux sauvages. Nos résultats ont montré que la souris a évité de façon significative les signaux chimiques complexes du furet et un signal chimique ubiquitaire des plantes, lié à la maturation et la pourriture des aliments (l’éthanol). La protéine du chat Fel d 1, laquelle fait partie de la famille des sécrotoglobines et est un allergène majeur du chat, n’a pas modifié le comportement d’exploration de la souris ou son comportement de recherche et de consommation de nourriture. Le composant chimique des fèces de renard, le TMT a induit un évitement clair et des réponses de stress comme cela a été rapporté dans la littérature. De plus, j’ai fait une revue de la littérature pour évaluer et discuter les méthodes de contrôle des rongeurs d’un point de vue éthique, revue qui a démontré que les méthodes actuelles peuvent être considérés inhumaines et ne correspondent pas aux attentes actuelles de la société et aux standards sur le bien-être dans d’autres domaines comme les élevages de production ou les animaux de laboratoire. Ces résultats ouvrent des nouvelles voies de recherche afin d’identifier les composants chimiques du furet et des plantes liés au comportement d’évitement des rongeurs, les prochaines étapes utilisant des animaux sauvages à la fois en laboratoire et sur le terrainRodent commensal species produce great damage in agriculture and urban areas. As invasive species they can endanger local species and are carriers and vectors of several important zoonoses. Control methods rely mainly on the use of warfarins, which can be inadvertently be taken up by untargeted species. Warfarins have also lost their efficacy in rodents due to the development of genetic resistance. In addition, these methods are considered inhumane as they cause a slow and painful death due to haemorrhages. Olfaction is a main source for environmental risk assessment by rodents, and it can be used to modify their use of space. My aim in this thesis was to identify behavioural reactions of the house mouse (Mus musculus), using laboratory strains as models of wild animals, to ecologically meaningful chemical messages, including predator and plant chemical olfactory cues. My results showed that mice avoided complex ferret olfactory cues and ethanol which is a ubiquitous chemical related to fruit rotting and ripening. The feline protein Fel d 1, which belongs to the secretoglobin family and is a major cat allergen in humans, did not elicit significant avoidance or alter foraging behaviour in mice. However, Trimethylthiazoline purified from fox faeces, elicited clear avoidance behaviour and stress responses. I carried out a bibliographic review to evaluate and discuss rodent pest control methods from an ethical standpoint. This literature showed that many of the current methods of pest control are considered inhumane, and do not tally with current society concerns and welfare standards in other domains such as farms or laboratory animals. These results raise new research questions to identify ferret and plant chemical compounds that can induce rodent avoidance, and to carry out next stage of research with wild animals both under laboratory and field conditions