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Shadung, Kagiso Given. "Improving attractiveness of an insect pest through value-addition : A possible insect management strategy." Thesis, University of Limpopo ( Turfloop campus), 2012. http://hdl.handle.net/10386/756.
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Thesis (M.Sc. (Plant Protection)) --University of Limpopo, 2012Attractiveness of insect pest for use as sources of food may be improved by providing information on preservation and relevant nutritional value. Nutritional composition in edible insects may depend on drying method and/or vegetation (location). Influence of drying method and location on nutritional composition of the African metallic wood boring beetle (Sternocera orissa), widely consumed in certain rural communities of Limpopo Province, South Africa, was investigated. Randomised complete block design in a 3 x 3 factorial arrangement was used with three drying methods (oven-drying, freeze drying, cooking method) and three locations (Khureng, Magatle, Ga-Masemola), with three replicates. Nutritional composition data were subjected to a two-way analysis of variance (ANOVA) and means were separated using Turkey Honestly Significant Differences (HSD) at 5 % level of significance. Relative to freeze-drying, oven-drying and cooking methods increased protein, carbohydrates, fat, energy, ash and dry matter content with the exception of cooking method, which decreased the moisture content. Compared to other locations, Ga-Masemola significantly increased fat and energy of the test beetle. Relative to the freeze-drying method, oven-drying and cooking increased (P ≤ 0.05) essential and non-essential amino acids. Location did not have significant effect on the essential and non-essential amino acids of S. orissa across all the villages. Similarly, oven-drying and cooking increased K, P, Fe, Zn and Mg. Compared to locations, Ga-Masemola increased (P ≤ 0.05) Fe of the test beetle. Results of the study suggested that oven-drying and cooking methods improved the nutritional composition of S. orissa, which has the potential of enhancing nutrition in marginal rural communities of Limpopo Province. Providing results of this study to rural communities through extension services has the potential of improving the attractiveness of this beetle to marginal communities, and thus, increasing harvesting and therefore, reduce insects population densities.
the Technology Innovation Agency (TIA) and the National Research Foundation
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Gryj-Rubenstein, Ellen Orli. "Conflicting forces shaping reproductive strategies of plants : florivory and pollination /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/5126.
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Warwick, Stuart. "Nutritional regulation and spermatophylax donation in the mating system of Gryllodes sigillatus (Orthoptera: Gryllidae)." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325532.
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Karlsson, Mattias, and Samuel Martinsson. "iNsect Preventer." Thesis, Högskolan i Halmstad, Sektionen för ekonomi och teknik (SET), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-26211.
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Dantas, Iron Macedo [UNESP]. "Distribuição espacial e plano amostragem seqüencial para a lagarta do minador-dos-citros Phyllocnistis citrella Stainton, 1856 (Lepidoptera: Gracillariidae), em laranjeira 'Pêra-Rio' Citrus sinensis (L.) Osbeck." Universidade Estadual Paulista (UNESP), 2002. http://hdl.handle.net/11449/105310.
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dantas_im_dr_jabo.pdf: 1564795 bytes, checksum: b13a33d6084828753dd2f2e94108f7e3 (MD5)A distribuição do minador-dos-citros, Phyllocnistis citrella Stainton, foi estudada em pomares comerciais de laranjeira 'Pêra-Rio' (Citrus sinensis), com três e dez anos de idade, durante os anos de 2000 e 2001, nos municípios de Taiúva e Jaboticabal, São Paulo, Brasil. No estudo da distribuição na planta, constatou-se que os ovos e as lagartas de P. citrella encontram-se distribuídos por toda a planta, podendo ser realizadas amostragens tanto nas partes inferior e superior, quanto nos quatro quadrantes da planta. Esse inseto preferiu ovipositar na face inferior das folhas mais novas, localizadas no ápice dos brotos, medindo até três centímetros. Constatou-se que a concentração de lagartas no broto aumenta no sentido da extremidade para a base, como também das folhas menores para as maiores. Entre plantas constatou-se que na maioria das amostragens, os índices estudados (Razão variânciaImédia, índice de Morisita, Índice de Green, kcomun da distribuição binomial negativa, b de Taylor e ß da regressão de aglomeração média de Iwao) indicaram que a P. citrella apresenta distribuição agregada. Entre as três distribuições estudadas: binomial negativa, binomial positiva e Poisson, a distribuição binomial negativa foi o modelo que melhor ajustou-se à distribuição da lagarta do minador dos citros em pomares de laranjeira 'Pêra-rio'. Foram desenvolvidos planos de amostragem seqüencial e construídas tabelas para levantamento em campo.
The distribution of the citrus leafminer, Phyllocnistis citrella (Stainton), was studied at 'Pêra-Rio'orange (Citrus sinensis) commercial orchards, with three and ten years old, during the years of 2000 and 2001, at Taiúva and Jaboticabal county, São Paulo State, Brazil. In the study of distribution in the plant, as the eggs and larvae of P. citrella are distributed by the whole plant, samplings in the plant could be accomplished both in the inferior or superior part as in the four quadrants. This insect has preference for oviposition on the inferior face of newest leaves, located at the apex of sprout, measuring up to three centimeters. It was verified that the concentration of larvae in the sprout increases from the apex to the basis, as well as from the smallest to the largest leaves. Among plants, it was verified that in most of the samplings, the studied indexes (Reason variance/mean ratio, Morisita's index, Green's dispersion coefficient, kcommon of the negative binomial distribution, b of Taylor's power law and ß of the Iwao's patchiness regression) indicated aggregated spatial arrangement. Among the three studied indexes, binomial, negative binomial and Poisson, the negative binomial distribution, was the best model to fit the spatial distribution of the citrus leafminer in 'Pêra-Rio' orange orchards. Sequential sampling plans were developed and tables for field monitoring were built.
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Jonsson, Mattias. "Dispersal ecology of insects inhabiting wood-decaying fungi /." Uppsala : Swedish University of Agricultural Sciences, 2002. http://diss-epsilon.slu.se/archive/00000064/.
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Thesis (doctoral)--Swedish University of Agricultural Sciences, 2002.Thesis documentation sheet inserted. Appendix reprints three manuscripts and one published paper, three of which are co-authored with others. Includes bibliographical references. Also issued electronically via World Wide Web in PDF format; PDF version lacks abstract, ack., and appendix. One ill. in PDF version is in col.
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Groen, Simon Cornelis. "Manipulation of plant-insect interactions by insect-borne plant viruses." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648187.
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Lomaliza, Kanda. "An insect-food reactor for human food supply." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22364.
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Demary, Kristian C. "Connecting pre- and post-mating episodes of sexual selection in Photinus greeni fireflies /." Thesis, Connect to Dissertations & Theses @ Tufts University, 2005.
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Thesis (Ph.D.)--Tufts University, 2005.Adviser: Sara M. Lewis. Submitted to the Dept. of Biology. Includes bibliographical references. Access restricted to members of the Tufts University community. Also available via the World Wide Web;
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Minakawa, Noburu. "The dynamics of aquatic insect communities associated with salmon spawning /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/5496.
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Strevens, Chloë. "Insect metapopulation dynamics." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:3e6c30d1-6c88-42d0-92d8-83c59f4269d2.
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Metapopulation ecology has developed to explain the population dynamics that occur in spatially structured landscapes. In this study, I combined an empirical laboratory approach, using metapopulation microcosms of Callosobruchus maculatus and its endospecific parasitoid Anisopteromalus calandrae, with mathematical population models in order to investigate several fundamental metapopulation processes. Population dynamics in these systems can be studied at two scales; the local patch-wise scale and the regional metapopulation scale. Here I demonstrate that in both homogeneous and heterogeneous landscapes knowledge of local scale demographic processes is necessary in order to understand regional metapopulation dynamics. The differences in the rate and net direction of dispersal between patches as a result of the permeability of the matrix in homogeneous systems and density-dependent dispersal in heterogeneous systems were also explored. Metapopulation dynamics rely on a balance between local extinctions and recolonisations. Therefore, increasing local mortality rates is likely to be detrimental to the persistence of the system. Here, the impact of several common harvesting strategies on the persistence of a host-parasitoid metapopulation was examined. Contrary to expectation I discovered that harvesting in these systems increased both local and regional population sizes. The increased population size as a result of increased mortality was explained in terms of a hydra effect, where harvesting relaxed density-dependence acting on local host populations. The results presented in this thesis are relevant for the monitoring, management and conservation of natural metapopulations and the development of sustainable harvesting strategies in structured landscapes.
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Melano, Timothy. "Insect-Machine Interfacing." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/145388.
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A terrestrial robotic electrophysiology platform has been developed that can hold a moth (
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Pereira, Kleber de Sousa. "Competição larval em parasitoide gregário de pupas em broca das cucurbitáceas." Universidade Federal de Viçosa, 2014. http://locus.ufv.br/handle/123456789/3994.
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Insect hosts that have been already parasitized are considered a low quality resource, which may affect the number of ovipositions made by other parasitoids. Since the amount of eggs laid affects the host immune response, the offspring survivorship may also be affected. For this reason, it is necessary to understand to what point the energy spent in superparasitizing is an advantage that allows supression of host immune response and provides adequate resources for the imatures to develop within their host. This study had the objective of finding the number of ovipositions from Palmistichus elaeisis (Hymenoptera: Eulophidae) allowing optimal offspring fitness and to analyze if immune response the melonworm Diaphania hyalinata L. (Lepidoptera: Crambidae) is correlated with the density of posture by the parasitoid. Pupae of D. hyalinata received from one to five parasitoid ovipositions. The total number of offspring produced, the number of males and females emerging from the host, sex ratio, life cycle, average body mass and biomass produced per parasitized pupae were recorded for the different oviposition densities. Digital x-ray imaging of parasitized hosts were recorded to assessing the immature parasitoid developmental until adult emergence. Incidence of unviable parasitoid larvae was also recorded. The survivorship of P. elaeisis was daily assessed. Hemocyte dynamics and encapsulation capacity of D. hyalinata against P. elaeisis was evaluated for each number of ovipositions, from one to five. The Parasitoid developmental time decreased with increased oviposition density and three ovipositions provided higher offspring and particularly female production, and optimal larval fitness. Progeny body mass and sex ration were not affected by oviposition density. Female and male survived longer with one oviposition of the female parasitoid. Parasitoid emergence increased with the number of parasitoid ovipositions and 100% parasitism and corresponding 100% host pupa mortality were achieved with all oviposition densities. Increased number of ovipositions decreased the number of total hemocytes, and also of granulocytes, plasmatocytes and prohemocytes in the circulating host hemolymph. Oenocytes and espherulocytes were not affect by the number of parasitoid ovipositions in the host. The melanization and encapsulation rates decreased with the number of ovipositions by P. elaeisis. Three ovipositions by the parasitoid female allowed optimal progeny production and parasitoid performance. Superparasitism is a strategy of P. elaeisis for optimal progeny fitness balancing optimal progeny performance with amelioration of host immune response.
Hospedeiros parasitados são considerados de baixa qualidade e podem influenciar no número de oviposições de parasitoides, influenciando na sobrevivência da progênie, pois, a quantidade de ovos depositados afeta a resposta imune do hospedeiro. Por isso, torna-se necessário saber até quando o investimento de superparasitar é vantajoso ao ponto de suprimir a resposta imune do hospedeiro e favorecer uma ótima competição de imaturos dentro do hospedeiro. O objetivo desta pesquisa foi reconhecer a densidade ótima de posturas de Palmistichus elaeisis (Hymenoptera: Eulophidae) para produção de progênie, e saber se a resposta imune do hospedeiro Diaphania hyalinata L. (Lepidoptera: Crambidae) ao parasitismo se relaciona a esta densidade ótima. Pupas de D. hyalinata foram expostas a uma, duas, três, quatro e cinco posturas por uma mesma fêmea do parasitoide. O número total de progênies, de machos e fêmeas emergidos, razão sexual, ciclo de vida, peso médio e biomassa produzida foram analisados. A velocidade de pupação, tempo entre pupa e emergência de P. elaeisis e a porcentagem de pupas com imaturos inviáveis deste parasitoide foram observados em pupa de D. hyalinata em sistema de radiografia digital. A sobrevivência de adultos de P. elaeisis foi avaliada diariamente. A porcentagem de emergência da progênie foi avaliada. A dinâmica hemocitária e a capacidade de encapsulação por pupas de D. hyalinata contra P. elaeisis foi avaliada mediante o número de posturas. Larvas de P. elaeisis empuparam mais rápido e o tempo entre o período de pupa e a emergência foi praticamente constante com três oviposições, variando para os demais tratamentos. Três oviposições proporcionou o maior número de fêmeas, total de emergidos e desempenho e, menor tempo de desenvolvimento dos parasitoides. O peso da progênie e a razão sexual foram semelhantes entre os indivíduos. Fêmeas e machos de pupas com uma oviposição sobreviveram mais que os demais tratamentos. A porcentagem de emergência de parasitoides aumentou com o número de posturas. O parasitismo foi de 100% em todos os tratamentos. Pupas com quatro e cinco oviposições não tiveram larvas inviáveis. O aumento do número de posturas reduziu o número de hemócitos totais e de granulócitos, plasmatócitos e prohemócitos circulantes na hemolinfa de pupas de D. hyalinata. Oenocitóides e esferulócitos circulantes mostraram padrão aleatório entre os tratamentos. A taxa de encapsulamento e de melanização decresceram com o aumento de oviposições de P. elaeisis. A oviposição por três vezes maximizou a progênie, reduziu o tempo de desenvolvimento e aumentou o desempenho de P. elaeisis. O superparasitismo é uma estratatégia em P. elaeisis para o aumento de sobrevivência e desempenho da prole.
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Zhou, Yanmin. "Insect adhesion on rough surfaces and properties of insect repellent surfaces." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709055.
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Higgins, Charlene J. "Spatial distribution and reproductive biology of western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera : Thripidae)." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/29873.
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Western flower thrips (WFT), Frankliniella occidentalis (Pergande), are haplodiploids. Virgin females produce sons parthenogenetically but must be mated to produce daughters. As a result, primary and secondary (adult) sex ratios can diverge from the 1:1 ratio commonly observed in diploid systems. Field studies were conducted to examine the spatial distribution of WFT on two greenhouse crops, Bell peppers, Capsicum annuum (Linn.) and Long English cucumbers, Cucumis sativus (Linn.) to determine if there was a correlation between sex ratio and density. Leaf and flower samples were taken weekly. All adult and immature WFT were counted and sex of adults determined. Yellow sticky traps were used to monitor density and sex ratio of the dispersing adult population. Lab studies were also done to investigate if male availability affected the sex ratio and number of offspring produced by individual females. Laboratory experiments were done to assess the effects of sperm availability and maternal age on sex ratio of progeny produced.
On both crops, 84 to 95 % of adult WFT in flowers were females and most larvae (> 85 %) were found on leaves. Male WFT were rare on all plant parts even when caught in high numbers on traps. Approximately 75 % of females found on plants in the greenhouse were mated. Most (70 - 90 %) WFT on traps at low densities (< 200 individuals/trap) were males. This suggests that WFT populations are initiated by virgin females that likely overwintered as pseudopupae in the greenhouse. These females initially produce only sons, and may have to wait for these to emerge before they mate and produce daughters. As WFT density within a greenhouse increases, females are probably mated soon after emergence. Sex ratio of adults on traps becomes more female biased as density increases within a greenhouse. Heavily female biased (> 65 %) sex ratios were found on traps at high population densities (> 200 individuals/trap). Sex ratio
of adults on traps remained male biased in the pepper greenhouse (WL) where the population density of WFT remained low. Information regarding within-plant distribution of thrips is essential for population monitoring and control. Used together, regular examination of flowers and counts of adults on sticky traps allow quick detection of potential "hot spots" of WFT density. Sex ratio and density are highly correlated. Sex ratio of the dispersing adult population is a good predictor of outbreak potential of the extant WFT population.
Two WFT predators found in greenhouses were also monitored to document their effects on WFT population density and sex ratio. Mass introductions of the predatory mite, Amblysieus cucumeris, did not successfully control WFT in most greenhouses monitored. A natural infestation of pirate bugs, Orius tristicolor occurred in the only pepper house monitored. WFT density remained low throughout the growing season. O. tristicolor shows promise for future use in integrated pest management programs designed to control F. occidentalis in commercial greenhouses.
Lab studies showed that sex ratio of offspring produced by mated females was influenced by sperm supply and maternal age. Mated females produced sons and daughters which suggests that females control sex of offspring produced through selective fertilization. Once mated, two-thirds of offspring produced are females. Older females produced fewer daughters than younger females.
A principle conclusion from this study is that sex ratio of the WFT population within a greenhouse can be used to predict future population dynamics. Male availability may be the most important factor affecting the number of daughters produced by individual females which in turn may determine the potential of WFT populations to increase.Science, Faculty of
Zoology, Department of
Graduate
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Burkett, Nathan Daniel Mullen Gary R. "Comparative study of gravid-trap infusions for capturing blood-fed mosquitoes (diptera : culicidae) of the genera Aedes, Ochlerotatus, and Culex." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Summer/master's/BURKETT_NATHAN_18.pdf.
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Ross, Sally Jane. "The phytophagous insect community on the Veld Fig, Ficus Burtt-Davyi Hutch." Thesis, Rhodes University, 1994. http://hdl.handle.net/10962/d1005425.
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The quest for patterns in community organisation is a daunting task which may be made easier by concentrating on communities associated with a restricted range of resources and therefore of relative simplicity. Here, the phytophagous insect community on the African fig tree Ficus burtt-davyi Hutch. was studied in an attempt to gain some insight into the factors which influence the composition of insect herbivore communities at a very local level, on individual plants of one host species at a single location. The tree's phenological patterns were detennined, due to their relevance to herbivores, particularly those which are host-specific feeders. The trees exhibited inter-tree asynchrony and intra-tree synchrony in fruit crop initiation, whereas leaf production was synchronous both within and between trees. Sixteen frequently occurring phytophagous insect species fed on the 123 F. burtt-davyi trees in the study area over a period of one year. Factors with the potential to influence the composition of this community were investigated at levels of the whole community (species richness), the guild, and the individual species. At each 'level' the effects of the measured factors on fluctuations in community composition were investigated, both over time (i.e. temporally) and spatially from tree to tree. During the year the phytophage community was influenced largely by temperature, although rainfall and tree phenological changes did exert varying influences on the abundances of guilds and individual species. Tree to tree variation in species richness (and thus commensurately, in the frequencies of occurrence of guilds and individual species) was influenced primarily by tree architectural complexity. Architecturally more complex trees hosted a greater number of species, a relationship largely attributable to effects of passive sampling and within-tree microhabitat heterogeneity and/or the availability of living space. The distributions of the leaf and stem piercing species were strongly associated with the presence of ants and this relationship manifested itself within the community as a whole. The degree of isolation of trees had consequences for individual species and for overall species richness, with the numbers of species present decreasing as trees became more isolated. A detailed analysis of guild distributional patterns revealed that the most important influential factors were those also evident at the level of the whole community and that species within guilds were, on the whole, no more similar to one another with respect to their habitat preferences than species from different guilds. The grouping of species into functional units therefore threw no additional light on the way in which this community is organised. An analysis of possible interspecific interactions between all of the phytophagous species in the community revealed only positive associations, both between species within guilds and between those in different guilds. These were doubtless attributable to autocorrelation as a result of similar habitat preferences. Competition was therefore rejected as an organising force within the community.
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Cerqueira, Nicole. "Pollinator visitation preference on native and non-native congeneric plants." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 2.91 Mb., 84 p, 2005. http://wwwlib.umi.com/dissertations/fullcit/1428175.
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McNett, Gabriel Dion. "Noise and signal transmission properties as agents of selection in the vibrational communication environment." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/4677.
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Thesis (Ph. D.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on February 25, 2008) Vita. Includes bibliographical references.
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Riveros, Rivera Andre J. "Body Size and the Neural, Cognitive and Sensory Basis of Sociality in Bees." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/145712.
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Body size is a universal property affecting biological structure and function, from cell metabolism to animal behavior. The nervous system, the physical generator of behavior, is also affected by variations in body size; hence potentially affecting the way animals perceive, interpret and react to the environment. When animals join to form groups, such individual differences become part of the structure of the society, even determining social roles. Here, I explore the association between body size, behavior and social organization in honeybees and bumblebees. Focusing on bumblebees, I explore the link between body size, brain allometry and learning and memory performance, within the context of task specialization. I show that body size goes along with brain size and with learning and memory performance, and that foraging experience affects such cognitive and neural features. Next, I explore the association between body size and foraging task specialization in honeybees. Previous evidence showed a link between specialization on pollen or nectar foraging and sensory sensitivity, further associating sensitivity to the quality and/or quantity of resource exploited. I hypothesize that, as in solitary bees, larger body size is associated with higher sensory sensitivity. I test this hypothesis by comparing body size and the quality and quantity of the resource exploited by wild Africanized and European honeybees. I show that nectar foragers are smaller and have fewer olfactory sensilla, which might underlie their lower sensitivity to odors. Also, larger bees collect more pollen (within pollen foragers) and more dilute nectar (within nectar foragers). To further test this `size hypothesis', I compare strains of bees selected to store large ("high strain") or small ("low strain") amounts of pollen surplus. As these strains differ in sensory sensitivity, I predict that the more sensitive high strain bees are larger and have more sensory sensilla. I show that high strain bees are generally bigger, but have fewer sensory sensilla than low strain bees. These results show that in bees, body size is associated with an individual's sensory, neural and cognitive features, further suggesting that body size plays a more important role in the organization of bee societies than generally assumed.
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Winskill, Peter. "Evaluation of transgenic insects for use in the control of insect-borne disease." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/45393.
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The burden of many vector-borne diseases remains high and for some, such as dengue fever, continues to rise. It is estimated that up to half of the global population is at risk from dengue. Treatment of dengue fever is currently limited to case management and there are, at present, no licensed vaccines available. As a result, the front-line defence against dengue fever remains vector control. Modern approaches to vector control are attempting to push forward new techniques to target the mosquito vectors of dengue. One such technique is the release of transgenic insects that are genetically sterile due to a conditional dominant lethal gene. This modern adaptation of the traditional sterile insect technique is at the forefront of current new vector control solutions. The success of a vector control effort using releases of transgenic insects relies on the technology being efficacious as well as effective in the field. To ensure the effectiveness of field-released sterile insects a deep knowledge of the mosquito biology and ecology must be combined with site-specific, logistical and cost considerations. In order to maximise the potential of this technology the field releases of these insects must be optimised. This work includes a specific focus on the exploration of the dynamics of releasing different life stages, investigations into the biology and ecology of the released insects and the development of applied methodology relating to the release and monitoring of transgenic insects. Novel vector control techniques, such as the use of transgenic insects, have an important role to play in addressing the emergence and spread of dengue fever. In order to utilise these technologies to their full potential they must be optimised to maximise their effectiveness. In this thesis I present work towards this optimisation.
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Dantas, Iron Macedo. "Distribuição espacial e plano amostragem seqüencial para a lagarta do minador-dos-citros Phyllocnistis citrella Stainton, 1856 (Lepidoptera: Gracillariidae), em laranjeira 'Pêra-Rio' Citrus sinensis (L.) Osbeck /." Jaboticabal : [s.n.], 2002. http://hdl.handle.net/11449/105310.
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Orientador: José Carlos BarbosaBanca: Pedro Takao Yamamoto
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Banca: Francisco Jorge Cividanes
Resumo: A distribuição do minador-dos-citros, Phyllocnistis citrella Stainton, foi estudada em pomares comerciais de laranjeira 'Pêra-Rio' (Citrus sinensis), com três e dez anos de idade, durante os anos de 2000 e 2001, nos municípios de Taiúva e Jaboticabal, São Paulo, Brasil. No estudo da distribuição na planta, constatou-se que os ovos e as lagartas de P. citrella encontram-se distribuídos por toda a planta, podendo ser realizadas amostragens tanto nas partes inferior e superior, quanto nos quatro quadrantes da planta. Esse inseto preferiu ovipositar na face inferior das folhas mais novas, localizadas no ápice dos brotos, medindo até três centímetros. Constatou-se que a concentração de lagartas no broto aumenta no sentido da extremidade para a base, como também das folhas menores para as maiores. Entre plantas constatou-se que na maioria das amostragens, os índices estudados (Razão variânciaImédia, índice de Morisita, Índice de Green, kcomun da distribuição binomial negativa, b de Taylor e ß da regressão de aglomeração média de Iwao) indicaram que a P. citrella apresenta distribuição agregada. Entre as três distribuições estudadas: binomial negativa, binomial positiva e Poisson, a distribuição binomial negativa foi o modelo que melhor ajustou-se à distribuição da lagarta do minador dos citros em pomares de laranjeira 'Pêra-rio'. Foram desenvolvidos planos de amostragem seqüencial e construídas tabelas para levantamento em campo.
Abstract: The distribution of the citrus leafminer, Phyllocnistis citrella (Stainton), was studied at 'Pêra-Rio'orange (Citrus sinensis) commercial orchards, with three and ten years old, during the years of 2000 and 2001, at Taiúva and Jaboticabal county, São Paulo State, Brazil. In the study of distribution in the plant, as the eggs and larvae of P. citrella are distributed by the whole plant, samplings in the plant could be accomplished both in the inferior or superior part as in the four quadrants. This insect has preference for oviposition on the inferior face of newest leaves, located at the apex of sprout, measuring up to three centimeters. It was verified that the concentration of larvae in the sprout increases from the apex to the basis, as well as from the smallest to the largest leaves. Among plants, it was verified that in most of the samplings, the studied indexes (Reason variance/mean ratio, Morisita's index, Green's dispersion coefficient, kcommon of the negative binomial distribution, b of Taylor's power law and ß of the Iwao's patchiness regression) indicated aggregated spatial arrangement. Among the three studied indexes, binomial, negative binomial and Poisson, the negative binomial distribution, was the best model to fit the spatial distribution of the citrus leafminer in 'Pêra-Rio' orange orchards. Sequential sampling plans were developed and tables for field monitoring were built.
Doutor
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Ahern, Robert G. "Phylogeography of an introduced insect pest and consequences of an insect introduction." College Park, Md. : University of Maryland, 2007. http://hdl.handle.net/1903/6707.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2007.Thesis research directed by: Entomology. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Smith, Lincoln. "Insect inspired visual homing." Thesis, University of Sussex, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443981.
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Anderson, James Clive. "Synthesis of insect antifeedants." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/47747.
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Crosswhite, F. S., and C. D. Crosswhite. "Editorial - Insect-Plant Relationships." University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/609111.
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Tickes, B., and M. Rethwisch. "Bermuda Grass insect Control." College of Agriculture, University of Arizona (Tucson, AZ), 1988. http://hdl.handle.net/10150/200824.
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McGinley, Susan. "Iron Metabolism in Humans and Insects: Implications For Human Health and For Insect Control." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2001. http://hdl.handle.net/10150/622261.
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Beal, Benjamin D., and Benjamin D. Beal. "Using Insects for STEM Outreach: Development and Evaluation of the UA Insect Discovery Program." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/622902.
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Science and technology impact most aspects of modern daily life. It is therefore important to create a scientifically literate society. Since the majority of Americans do not take college-level science courses, strong K-12 science education is essential. At the K-5 level, however, many teachers lack the time, resources and background for effective science teaching. Elementary teachers and students may benefit from scientist-led outreach programs created by Cooperative Extension or other institutions. One example is the University of Arizona Insect Discovery Program, which provides short-duration programing that uses insects to support science content learning, teach critical thinking and spark interest in science. We conducted evaluations of the Insect Discovery programming to determine whether the activities offered were accomplishing program goals. Pre-post tests, post program questionnaires for teachers, and novel assessments of children’s drawings were used as assessment tools. Assessments were complicated by the short duration of the program interactions with the children as well as their limited literacy. In spite of these difficulties, results of the pre-post tests indicated a significant impact on content knowledge and critical thinking skills. Based on post-program teacher questionnaires, positive impacts on interest in science learning were noted as much as a month after the children participated in the program. New programming and resources developed to widen the potential for impact are also described.
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RONCOLINI, ANDREA. "Microbial aspects related to edible insects and development of new insect-based food products." Doctoral thesis, Università Politecnica delle Marche, 2020. http://hdl.handle.net/11566/273677.
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La FAO ha dichiarato che la popolazione umana è in continua crescita e raggiungerà i 9 miliardi nel 2050, provocando un aumento della domanda di cibo, in particolare di fonti proteiche, che si tradurrà in effetti negativi per l’ambiente. Una possibile soluzione potrebbe essere rappresentata dal consumo di insetti edibili: inannzitutto, per la sostenibilità ambientale legata al loro allevamento, ma anche per il loro contenuto in aminoacidi essenziali, acidi grassi insaturi, minerali, vitamine e fibre.
Nel 2015, gli insetti sono stati classificati come “novel food” con il Regolamento No 2015/2283. Nello stesso anno, l’EFSA ha sottolineato la necessità di ottenere maggiori informazioni sugli insetti per definirne il rischio microbiologico e chimico.
In questo contesto la presente tesi di Dottorato ha avuto lo scopo di studiare il microbiota associato agli insetti edibili per ottenere informaziori riguardo un loro possibile consumo alimentare. Inoltre, data la loro capacità di agire come serbatoio di geni trasferibili di antibiotico resistenza, che possono essere anche portati da patogeni, parte della ricerca è stata focalizzata sulla presenza di tali geni in campioni di insetto. In breve, è stata riscontrata la presenza di microorganismi commensali, agenti di deterioramento e patogeni ed anche di geni trasferibili di antibiotico resistenza. I risultati ottenuti hanno evidenziato l’influenza di vari fattori tra cui specie di insetto, substrato di crescita, condizioni di allevamento.
Infine, per superare lo scetticismo dei consumatori riguardo agli insetti edibili, sono stati ottenuti prodotti in cui la presenza degli insetti è stata mascherata. I campioni prodotti sono stati sottoposti ad analisi microbiologiche, tecnologiche e sensorali per valutarne l’applicabilità. I risultati hanno sottolineato la presenza di batteri sporigeni e l’effetto delle diverse specie di insetto sui parametri tecnologici e sull’accettabilità dei consumatori.FAO declared that human population is worldwide increasingly growing and in 2050 it will reach 9 billion people. The consequent increase in food demand, and in particular, in proteins will cause several negative effects on the environment due to the intensive animal farming. In this scenario, a potential solution is represented by edible insects. First of all, their rearing is characterized by a higher environmental sustainability than livestock. Moreover, they are a nutritious food especially in terms of essential amino acids, unsaturated fatty acids, minerals, vitamins and fibre. In the European Union, insects were defined as “novel food” by the Regulation (EU) No 2015/2283. In the same year, EFSA requested further research to better assess microbiological and chemical risks related to edible insects. In this context, the present PhD. thesis was aimed to investigate about edible insects microbiota to collect information about their feasibility as food. Furthermore, since they can act as reservoir of transferable antibiotic resistance genes which can even be carried by pathogens, part of the research was focused on the occurrence of such genes in edible insects samples. Briefly, results showed the presence of commensal, spoilage and potential pathogen agents and the occurrence of transferable resistance genes. Interestingly, data highlighted the influence of insect species, growth substrate, rearing and environmental conditions. Finally, to overcome consumers scepticism generated by insects consumption as food, the development of insect-based food products where insects are invisible was assessed. To get information about the feasibility of these products, microbiological, technological and sensory analysis were performed. In a few words, the presence of spore-forming bacteria was detected in each bread and in the rusks. Moreover a different insect powder effect on the technological parameters of bread and on the consumers appreciation was observed.
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D'Avila, Márcia. "Insetos visitantes florais em áreas de cerradão e cerrado sensu stricto no estado de São Paulo." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-24012007-155752/.
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Com o objetivo de conhecer a composição dos insetos e das plantas visitadas nas áreas de cerradão e cerrado sensu stricto, da Estação Experimental de Itirapina, SP, foram realizadas amostragens sistemáticas dos insetos nas plantas, no período de março de 2003 a fevereiro de 2004. Do total de insetos coletados nas flores, 63,3% e 63,8% são da ordem Hymenoptera, 17,1% e 2,5% da ordem Lepidoptera, 16% e 19,5% da ordem Coleoptera e 3,6% e 12,8% da ordem Diptera, respectivamente, para as áreas de cerradão e cerrado sensu stricto, e 1,4% para Hemiptera-Heteroptera no cerrado sensu stricto. A maioria dos insetos coletados, visitando e/ou forrageando, nas duas áreas, foi no período da manhã, exceto os dípteros que preferiram o período da tarde. Na área de cerradão as espécies dominantes de Hymenoptera foram: Exomalopsis (Exomalopsis) sp. e Trigona spinipes; de Lepidoptera foram: Aeria olena e Ithomia agnosia; de Coleoptera foram: Nycterodina sp. e Spintherophyta sp.. Já na área de cerrado sensu stricto os hymenópteros dominantes foram: Apis mellifera, Exomalopsis cf. analis, Tetrapedia rugulosa, Trigona spinipes e Pepsis sp., para Coleoptera foram: Spintherophyta sp., Compsus sp. e Epitragus similis; para Diptera foram: Eristalis sp. e Ornidia obesa. A família Apidae foi a mais rica em espécies e abundância, nas duas áreas de cerrado, seguindo o padrão geral encontrado em outras áreas neotropicais até o momento estudadas, apresentando muitas espécies com poucos indivíduos e poucas espécies com muitos indivíduos. Quanto a composição da flora, em ordem decrescente, as famílias Asteraceae, Melastomataceae, Apocynaceae, Malpighiaceae e Rubiaceae foram as mais representativas na área de cerradão. Na área de cerrado sensu stricto as famílias com maior número de espécies foram Fabaceae, Malpighiaceae, Asteraceae, Bignoniaceae e Myrtaceae. As espécies vegetais com maior percentual de insetos visitantes na área de cerradão foram Diplosodon virgatus (Lythraceae), Daphnopsis racemosa (Thymelaeaceae) e Borreria verticillata (Rubiaceae), e no cerrado sensu stricto foram Ocotea pulchella (Lauraceae) e Miconia rubiginosa (Melastomataceae). A família Apidae foi a que visitou maior número de espécies botânicas, seguida por Nymphalidae, Chrysomelidae, Halictidae e Vespidae, na área de cerradão. No cerrado sensu stricto foram Apidae, Syrphidae, Chrysomelidae, Curculionidae, Halictidae, Vespidae e Pompilidae. Dos insetos dominantes, Apis mellifera foi a que visitou o maior número de espécies de plantas, seguida de Exomalopsis (Exomalopsis) sp., Aeria olena e Trigona spinipes, no cerradão; e no cerrado sensu stricto foram Apis mellifera, Trigona spinipes, Exomalopsis cf. analis e Tetrapedia rugulosa.Systematic samplings of insects on plants were carried out with the aim of studying the insect composition and visited plants in cerradao and cerrado areas stricto sensus at the Experimental Station of Itirapina ? SP between March 2003 and February 2004. Considering all insects collected on flowers in the cerradao and cerrado areas stricto sensus , 63.3% and 63.8% were Hymenoptera, 17.1% and 2.5% were Lepidoptera, 16.0% and 19.5% were Coleoptera and 3.6% and 12.8% were Diptera, respectively, while in the cerrado stricto sensus 1.4% were Hemiptera-Heteroptera. Most insects collected were visiting and/or foraging in the areas during the morning, except for diptera, which preferred the afternoon period. The dominant species within each order in the cerradao area were: Hymenoptera - Apis mellifera, Exomalopsis (Exomalopsis) sp. and Trigona spinipes; Lepidoptera - Aeria olena and Ithomia agnosia; Coleoptera - Nycterodina sp. and Spintherophyta sp.. In the cerrado area stricto sensus the dominant species were: Hymenoptera - Apis mellifera, Exomalopsis cf. analis, Tetrapedia rugulosa, Trigona spinipes and Pepsis sp.; Coleoptera - Spintherophyta sp., Compsus sp. and Epitragus similis; Diptera - Eristalis sp. and Ornidia obesa. The Apidae Family was the richest in species and most abundant in both cerrado areas, following the general pattern of other Neotropical areas already studied, with many species with few individuals and few species with many individuals. Regarding the floristic composition, the most representative families in the cerradao area were, in order, Asteraceae, Melastomataceae, Apocynaceae, Malpighiaceae and Rubiaceae. Families with most species in the cerrado area stricto sensus were Fabaceae, Malpighiaceae, Asteraceae, Bignoniaceae and Myrtaceae. The plant species in the cerradao area with the greatest percentage of visiting insects were Diplosodon virgatus (Lythraceae), Daphnopsis racemosa (Thymelaeaceae) and Borreria verticillata (Rubiaceae), while in the cerrado stricto sensus they were Ocotea pulchella (Lauraceae) and Miconia rubiginosa (Melastomataceae). The Apidae family was the one visiting most plant species in the cerradao area, followed by Nymphalidae, Chrysomelidae, Halictidae and Vespidae families, while in the cerrado stricto sensus the families visiting most plant species were Apidae, Syrphidae, Chrysomelidae, Curculionidae, Halictidae, Vespidae and Pompilidae. Apis mellifera was the species among the dominant insects of the cerradao area which visited the greatest number of plant species, followed by Exomalopsis (Exomalopsis) sp., Aeria olena and Trigona spinipes. In the cerrado stricto sensus the insect species that visited the greatest number of plants were Apis mellifera, Trigona spinipes, Exomalopsis cf. analis and Tetrapedia rugulosa.
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Nseiri, Sony M. "Prothoracicotropic hormone in the insect, Rhodnius prolixus source in the brain and control of rhythmic release /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ43394.pdf.
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Clifton, Katherine M. "The effect on transcriptional activity of mutations that alter possible phosphorylation sites in Drosophila melanogaster ultraspiracle (USP)." Greensboro, N.C. : University of North Carolina at Greensboro, 2007. http://libres.uncg.edu/edocs/etd/1498Clifton/umi-uncg-1498.pdf.
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Thesis (M.S.)--University of North Carolina at Greensboro, 2007.Title from PDF t.p. (viewed Mar. 3, 2008). Directed by Vincent C. Henrich; submitted to the Dept. of Biology. Includes bibliographical references (p. 43-46).
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Weaver, David K. (David Keith). "The role of selected frass chemicals and cuticular lipid components in the orientation of certain larval Tenebrionidae /." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74340.
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The larvae of Tenebrio molitor Linne and Alphitobius diaperinus (Panzer) both aggregated upon substrates treated with aqueous extracts of conspecific larval frass. Lactic acid is a pheromone in the frass of both species. Alphitobius larvae were attracted to lactic acid, while lactic acid caused Tenebrio larvae to arrest.Propionic acid is a repellent pheromone present in Tenebrio frass, but the lactic acid-induced response is dominant. The role of these chemical factors in population orientation of the larvae of these mealworm species is discussed.
The cuticular lipids of the larvae of both species contained close-range attractants that had a role in aggregate formation. The Tenebrio cuticular lipid pheromone is predominately 8,9-pentacosanediol. The Alphitobius cuticular pheromone is a mixture of at least two compounds.
The ecological preferences of these larvae suggested that these aggregation pheromones increased the density of individuals per unit volume. This increased density had varying effects on the physiological development of Tenebrio individuals.
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Srivastava, Diane Sheila. "Ecological evolutionary limits of local species richness." Thesis, Imperial College London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244120.
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McNamee, Peter James. "The equilibrium structure and behavior of defoliating insect systems." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27439.
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Defoliating insect systems, defined for the purposes of this thesis as being composed of insects which defoliate forest trees and the species with which they interact, such as their host trees and their natural enemy complexes, exhibit
a wide variety of population behaviors. Similarly, a number of theories and models have been proposed to explain these behaviors. These theories emphasize the importance of different ecological processes, often concentrate on the defoliator and overlook the importance of other components. Also, much of the current understanding of the dynamics of these systems has come from forest pest research and management
programs, tailored towards specific pest problems and often very short term in nature.
This thesis develops and begins to test a general approach for the local dynamics of defoliating insect systems.
This framework outlines the system components that are necessary to predict the behavior of defoliating insect systems. It includes ways in which the equilibrium structure
of defoliating insect systems, defined as the number of equilibria for each system component, the population levels at which the equilibria occur, and the processes creating the equilibria, might be found. The framework also includes methods of inducing the qualitative behavior of these sys- terns, defined as the periodicity of defoliator outbreaks, the length of outbreaks, and the dynamics of other important system components between, during, and in the decline of defoliator outbreaks.
The study begins with a detailed literature review of historical theories of defoliating insect system behavior and of the documented behavior patterns of these systems. Major classes of behavior are identified, as well as the various ecological processes which have been invoked to explain these behaviors. An analysis and documentation of the equilibrium structure and behavior of three defoliating defoliating insect systems, the eastern blackheaded budworm, the eastern spruce budworm, and the jack pine sawfly, are then used to develop general rules about how equilibrium structure and behavior can be explained. This analysis, coupled with the literature review, is used to develop the framework. The framework is then tested against historical defoliator population data and general syntheses of defoliating
insect system research to assess its utility and predictability.
The major results of the thesis are as follows. First, it appears that the structure and behavior of a defoliating insect system can be explained with five dynamic variables: the abundances of the defoliator; the foliage; the forest; the parasitoid; and the disease; and the effects of weather acting on the defoliator. Second, there appear to be 4 classes of defoliating insect system behavior. Third, the behavior that a defoliating insect system will exhibit seems to be determined by the magnitude of weather effects on defoliator survival and recruitment, the parasitoid numerical
response to changing defoliator densities, the disease numerical response to changing defoliator densities, and the vulnerability of the forest to defoliation. Fourth, there seem to be four equilibrium structures the defoliator can exhibit, and one each for the parasitoid, the foliage, the forest, and the disease. Finally, the framework suggests that defoliating insect system structure and behavior can be induced with a particular, well-defined set of information.
The framework is successful when applied to particular defoliating insect systems for explaining their behavior, but less successful in explaining defoliator equilibrium structure for other systems. Opportunities for more thorough testing of the framework exist if the particular types of data outlined above are gathered for defoliating insect systems. This lack of data for testing the framework make it currently difficult to clearly define those systems in which the framework is useful and those systems in which it is not. Experiments to test the framework are described and suggestions for future types of applied research on defoliating insect systems are presented.Science, Faculty of
Zoology, Department of
Graduate
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Brito, Pedro Vale de Azevedo 1982. "Morfologia do sistema reprodutivo masculino e dos espermatozóides de Ephemeroptera (Insecta) e análise do seu potencial filogenético." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316190.
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Orientadores: Mary Anne Heidi Dolder, Frederico Falcão SallesTexto em português e inglês
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-20T13:00:35Z (GMT). No. of bitstreams: 1 Brito_PedroValedeAzevedo_D.pdf: 100648281 bytes, checksum: 084741b621bdeef83fe1e691e02ad06f (MD5) Previous issue date: 2012
Resumo: Entre as ordens de insetos alados com representantes vivos, os membros da ordem Ephemeroptera estão entre os mais antigos que existem. Suas ninfas são aquáticas e os adultos, alados, sobrevivem por pouco tempo, morrendo logo após o acasalamento. Ainda existem algumas dúvidas sobre a relação dos Ephemeroptera com os demais Pterygota, bem como algumas famílias dentro da ordem são atualmente consideradas parafiléticas. A morfologia do sistema reprodutivo masculino e dos espermatozoides dos insetos pode fornecer informações úteis para estudos filogenéticos. No entanto, tais estudos envolvendo espécies de Ephemeroptera são escassos. O objetivo deste trabalho foi estudar a morfologia do sistema reprodutivo masculino e dos espermatozoides de espécies de Ephemeroptera existentes no Brasil, analisando a variabilidade morfológica encontrada nessas espécies. No Brasil são encontradas espécies pertencentes a dez famílias de Ephemeroptera e analisamos a morfologia do sistema reprodutor masculino de seis espécies pertencentes a cinco famílias e os espermatozoides de 17 espécies pertencentes a nove famílias. Nas seis espécies a morfologia do sistema reprodutivo foi muito constante sem glândulas acessórias ou órgãos especializados no armazenamento de espermatozoides. No entanto, observamos diferentes padrões de organização da musculatura intrínseca dos ductos espermáticos, provavelmente refletindo diferenças na fisiologia reprodutiva de cada espécie. A morfologia dos espermatozoides se mostrou mais variável. As espécies da família Leptophlebiidae possuem espermatozoides aflagelados e imóveis. Nas demais famílias, os espermatozoides são flagelados e móveis. A organização do axonema se mostrou constante nas diferentes espécies com o padrão 9+9+0 típico para esses insetos. Apenas os microtúbulos acessórios mostraram variação na estrutura, podendo assumir o padrão de subunidades 13+7 ou 13+0. Os flagelos são caracterizados por apenas uma mitocôndria que se alonga por quase todo flagelo. A morfologia dos corpos acessórios dos flagelos varia entre as espécies. Parece haver correlação entre a organização das cristas mitocondriais e os corpos acessórios. A morfologia da vesícula acrossomal é variável podendo estar relacionada com diferenças na espessura do corion dos ovos. No início dos flagelos observamos o adjunto do centríolo, que acreditava-se estar ausente nos espermatozoides dos Ephemeroptera. Em uma espécie estudada o núcleo dos espermatozoides está associado paralelamente ao flagelo. Nossos resultados sugerem que os espermatozoides dos Ephemeroptera possuem variabilidade morfológica suficiente para fornecer dados para futuros estudos filogenéticos. No entanto, é preciso que mais espécies sejam estudadas aumentando a abrangência dentro do grupo. Alem disso, alguns pontos como a origem dos corpos acessórios dos espermatozoides dos Ephemeroptera precisam ser melhor estudados
Abstract: Ephemeroptera species are the oldest living winged insects. Their nymphs are aquatic and the adults are short living, dying just after mating. At the present, there are still some doubts about the phylogenetic relationships between Ephemeroptera and the other Pterygota. The morphology of the male reproductive systems and of the spermatozoa is useful to furnish data for phylogenetic studies. However, there are few studies on this subject for Ephemeroptera. This study analyzes the morphology of the male reproductive system and of the spermatozoa of Brazilian Ephemeroptera species.. Species from ten Ephemeroptera families are found in Brazil. In the present study we analyzed the male reproductive system of six species from five families. We also analyzed the sperm morphology of 17 species from nine families. The male reproductive systems analyzed were very similar in the different species, with no accessory glands or specialized organs for sperm storage. However, the intrinsic musculatures of the sperm ducts have different organization patterns, probably related to differences in the reproductive physiology of each species. Greater morphological variation was observed among the spermatozoa. Species from Leptophlebiidae family have aflagellate and immotile spermatozoa. Species from the other families have mobile and flagellate spermatozoa. The organization of the axoneme was the same in all species, with the 9+9+0 microtubule pattern, typical for this insect group. Only the accessory microtubules vary between the 13+7 and the 13+0 subunit patterns. The flagella are characterized by the presence of only one mitochondrion along the flagellum. The accessory bodies morphology may vary between the species and it seems to be correlated to the organization of the mitochondrial cristae and the accessory bodies morphology. The acrosomal vesicles have morphological variations that must be related to differences in the egg chorion thickness. A centriolar adjunct is observed at the flagellum anterior region of the spermatozoa. This structure was thought to be absent in the Ephemeroptera spermatozoa. One species studied has its nucleus laterally associated to the flagellum. Our results suggest that the spermatozoa of Ephemeroptera have enough morphological variation to furnish useful data for future phylogenetic studies. However, more species, representing different groups of the order must be studied, increasing the scope of these studies. Also some questions, such as the origin of the accessory bodies of Ephemeroptera must be further studied
Doutorado
Biologia Celular
Doutor em Biologia Celular e Estrutural
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Banks, John E. "The effects of landscape heterogeneity on insect populations : a study of pattern and scale /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/5166.
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ATTATHOM, Tipvadee. "Biotechnology for Insect Pest Control." 農学国際教育協力研究センター, 2004. http://hdl.handle.net/2237/8932.
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Takalo, J. (Jouni). "Towards natural insect vision research." Doctoral thesis, University of Oulu, 2013. http://urn.fi/urn:isbn:9789526203249.
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Abstract
Visual world is naturally correlated both spatially and temporally. The correlations are used in vision to enhance performance of neurons. For gaining maximal neural performance of the visual neurons, the experiments, from stimulus to the analysis, should be designed to take advantage of the correlations. In this thesis methods for generating and analyzing natural stimuli were examined by using computations and algorithms.
For analyzing responses to natural stimuli in visual neurons, a method with only a few assumptions was developed for estimating information rate in long responses. The novel method gave a good agreement with Shannon information rate with linear system and Gaussian input but was able to handle also nonlinear processing and non-Gaussian data.
Secondly, a computer controlled 3D virtual environment with a spherical screen was developed, with a large visual field. The image of the world was projected to the screen with a DLP projector, giving good enough temporal performance for insect vision research. A track-ball was used in closed loop experiments.
Thirdly, properties of single photon (“bump”) information transfer at various light levels were investigated in cockroach photoreceptor with a coarse computational model. At dim light (< 10 ph/s), where single bump responses were visible, shot noise was dominant. At higher light levels latency distribution of the bump decreased the information rate, but amplitude distribution of bump did not have an effect.
Fourthly, the contribution of K⁺ channels to information rate and energy consumption was investigated by creating a database of computation models with varying channel compositions. The information rate has a maximum as a function of mean conductance, which was a sum of the average K⁺ conductance and the leak conductance. This maximum was fine-tuned by the K⁺ channel composition, which had high so-called novel contribution and relatively low amount of other conductances.
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Hector, Andrew. "Insect herbivory on herbaceous legumes." Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243564.
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King, L. A. "Molecular biology of insect picornaviruses." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370278.
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Bomphrey, Richard J. "The aerodynamics of insect flight." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410318.
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Higgins, Sahran Louise. "Sexual selection and insect genitalia." Thesis, University of Exeter, 2009. http://hdl.handle.net/10036/83254.
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Sexual selection is generally accepted as being responsible for the rapid and divergent evolution of male genitalia and other primary reproductive characteristics in internal fertilisers, such as testes size and sperm length. Selection can act via three main processes: sperm competition, cryptic female choice and sexual conflict, however very few studies have directly addressed the patterns of selection, the degree of phenotypic and genotypic variability expected in genital morphology or the degree to which intromittent genitalia are dependent on male condition. The seedbug, Lygaeus equestris has greatly elongated intromittent genitalia, being almost as long the body. Here I determine whether this is a sexually selected trait and further assess the degree of genetic and phenotypic variability in the greatly elongated male intromittent organ in relation to other morphological components. Further to this, patterns of inheritance and allometry of such exaggerated genitalia were investigated, and of the degree of condition dependence of genital and general morphology was experimentally assessed by varying food availability during ontogeny. Finally, using experimental evolution, I manipulated the level of sexual selection by biasing adult sex-ratio (male-biased, equal-sex, female biased) and investigated potential correlated evolution of female reproductive morphology and fertile (eupyrene) and non-fertile (apyrene) sperm length and numbers in the Indian meal moth, Plodia interpunctella. The main findings indicated that genital length was sexually selected in L. equestris being negatively related to male fertilisation success and that there was great phenotypic variation in genitalia both across and within populations. Genital length was negatively allometric, in spite of being hugely elongated, and was significantly heritable with considerable evolvability. It was also evident that there was genetic variation in the condition dependence of genital length with a significant genotype-by-condition interaction and much reduced genetic variation in genital length in the poor food treatment. Male and female primary sexual traits of P. interpunctella were also shown to covary, but this pattern did not differ across treatments. Taken together, the results presented in this thesis do not support traditional hypotheses of genital evolution and instead suggests that male intromittent genital length of L. equestris is sexually selected in a similar way to secondary sexual characteristics. This is also true when examining primary sexual traits in P. interpunctella and further highlights the false dichotomy between primary and secondary sexual traits.
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Tjandra, Anggraeni S. "Studies on insect immune systems." Thesis, Swansea University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.639247.
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Improvements in the purification of Galleria mellonella haemocytes using Percoll gradients are described. This procedure resulted in 95% purity for plasmatocytes, 89% for granular cells and 69% for spherule cells. Using unwashed haemocytes taken directly off the Percoll gradients for making monolayers showed that Ca2+ ion concentration, incubation time and temperature affect the number of cells attaching to the coverslips. The inability of these unwashed cells to undertake phagocytosis is discussed. In contrast, separated and washed haemocytes were highly phagocytic although ingestion was confined to the plasmatocyte cell type. Maximal ingestion by the plasmatocyte was, however, obtained only after the readdition of the granular cells to the plasmatocyte monolayer, illustrating the necessity for cell-cell co-operation in this process. Phenoloxidase activity was also tested in separated cells and it has been confirmed that prophenoloxidase is present in the granular cell type which indicates that this system may be involved in the haemocyte co-operation process. Haemolymph from G. mellonella was tested for the presence of lectins using a range of vertebrate erythrocytes. Only French Press-treated haemolymph with calf and rabbit erythrocytes yielded positive results, however, the levels of haemagglutination were low. Analysis of the physical and chemical properties of G. mellonella lectin showed it to be Ca2+ ion dependent, heat-labile and precipitated by ammonium sulphate. Also, the haemagglutination could be inhibited maximally by lactose and the titre was unchanged in the presence of 2% BSA. G. mellonella lectin was purified via a three-step procedure utilizing ammonium sulphate precipitation, ion exchange chromatography with DEAE Sephadex, and affinity chromatography with Sepharose 4B. One band with an estimated molecular mass of 40 kDa in the lactose fraction is probably the isolated lectin.
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Moon, Alice E. "Immune signalling in insect cells." Thesis, Kingston University, 2009. http://eprints.kingston.ac.uk/20407/.
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Immune responses in insects include components and mechanisms that are highly evolutionarily conserved. In addition to providing insight into the insects themselves, knowledge of the conserved mechanisms involved in insect immunity can offer valuable insight that is broadly relevant to a wide variety of other species. Three aspects of insect immune cell signalling have been studied here. Cell signalling responses have been investigated in two insect cell lines following treatment with double stranded (ds) RNA, a common intermediate of viral replication. It has been established that both cell lines investigated, from the fruitfly Drosophila melanogaster and vector mosquito Aedes albopictus, do not exhibit activation of mitogen activated protein kinases (MAPKs) or NF-KB proteins as a direct response to dsRNA. Secondly, a detailed analysis of the mechanisms of transcriptional regulation has been carried out on the Drosophila drosomycin gene, a key factor both in terms of its function during the immune response and in terms of its role during previous characterisation of Drosophila immune signalling. The drosomycin promoter was found to be regulated independently by the Toll and IMD signalling pathways via distinct sequence elements. Finally, investigation of the responses of an A. albopictus cell line to treatment with bacterial cell wall components has revealed key differences in the mechanisms involved in immune-induced regulation of transcription compared with the model established in Drosophila. A role for p38 MAPK has been identified in the negative regulation of transcription of A. albopictus cecropin Ai, an inducible antimicrobial peptide gene.
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Ibrahim, E. A. "Studies on trypanosomatid-insect interactions." Thesis, University of Salford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356169.
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Hart, Adam G. "Task partitioning in insect societies." Thesis, University of Sheffield, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.392734.
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Loder, Natasha. "Insect species-body size distributions." Thesis, University of Sheffield, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284385.
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Lonsdale, Zoe Natasha. "Epigenetic mechanisms of insect polyphenisms." Thesis, University of Leicester, 2018. http://hdl.handle.net/2381/41220.
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Insects are emerging as a key lineage for the study of epigenetic phenomena. This is due to the variety of polyphenisms found in insects. In this thesis, the caste polymorphism of the buff-tailed bumblebee Bombus terrestris and the phase polymorphism of the desert locust Schistocerca gregaria are studied to elucidate the underlying epigenetic mechanisms. I establish the presence of allele-specific expression and methylation in B. terrestris. I used next-generation RNA-sequencing to establish the DNA methylation, alternative splicing, and gene expression patterns of B. terrestris worker reproduction. The presence of allele-specific methylation and allele-specific expression were then determined in the same context. Correlations with the aforementioned epigenetic mechanisms were drawn. One major finding was that a higher degree of methylation was witnessed in more highly expressed genes. Higher methylation levels were also associated with more differentially expressed genes and isoforms between workers of a different reproductive state. However, the association between allele-specific expression and allele-specific methylation was weak. The relationship between alternative splicing and the circadian clock in S. gregaria was investigated. The first evidence of genes with differential circadian isoform expression patterns is reported. Finally, I analysed whether genome-wide alternative splicing levels are an important component in ascertaining the varying levels of eusociality found in the Hymenoptera. Fewer splicing events per gene with multiple isoforms was found in more highly eusocial species compared with solitary and more primitively eusocial species. Thus this is the first evidence of an association between level of sociality and alternative splicing.