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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Interactions between larval Malacosoma disstria (Lepidoptera:Lasiocampidae) hemolymph and selected antigens

Giannoulis, Paschalis K. January 1900 (has links)
Thesis (Ph.D.). / Written for the Dept. of Natural Resource Sciences. Title from title page of PDF (viewed 2009/06/08). Includes bibliographical references.
22

Climate and outbreaks of the forest tent caterpillar in Ontario

Daniel, Colin John January 1990 (has links)
A review of the current understanding of forest tent caterpillar (Malacosoma disstria Hbn.) population dynamics in Ontario suggests that two climatic factors, the temperature at the time of larval feeding and the minimum temperature through the winter, play important roles in determining outbreaks. Comparing the pattern of defoliation to similarly scaled temperature records over 41 years in Ontario shows no relationship between the year to year dynamics of outbreaks and either the temperature through the larval feeding period or the minimum overwintering temperature. A long-term analysis suggests that outbreaks are less severe in those regions with low overwintering temperatures and a patchy distribution of host. This latter finding, combined with an analysis of the synchrony and spread of defoliation, suggests that adult dispersal may play an important role in shaping the dynamics of outbreaks. / Science, Faculty of / Zoology, Department of / Graduate
23

Categorization of Silent Intervals in Parkinsonian Speech: A Study of Pause

Gravelin, Anna Christine 16 August 2017 (has links)
No description available.
24

Flutuação populacional, distribuição espacial e plano de amostragem sequencial de Anticarsia gemmatalis (Hübner, 1818) (Lepidoptera: Erebidae) e Chrysodeixis includens (Walker, 1858) (Lepidoptera: Noctuidae) em diferentes cultivares de soja / Population fluctuation, spatial distribution and sequential sampling of Anticarsia gemmatalis (Hübner, 1818) (Lepidoptera: Erebidae) and Chrysodeixis includens (Walker, 1858) (Lepidoptera: Noctuidae) in different soybean cultivars

Santos, Leticia Serpa dos [UNESP] 27 April 2018 (has links)
Submitted by Leticia Serpa Dos Santos (leserpa15@hotmail.com) on 2018-06-12T19:49:21Z No. of bitstreams: 1 Tese_Leticia_Serpa_dos_Santos.pdf: 1204964 bytes, checksum: 50ea21a5746571da15672c9df3679bda (MD5) / Approved for entry into archive by Alexandra Maria Donadon Lusser Segali null (alexmar@fcav.unesp.br) on 2018-06-13T17:14:14Z (GMT) No. of bitstreams: 1 santos_ls_dr_jabo.pdf: 1204964 bytes, checksum: 50ea21a5746571da15672c9df3679bda (MD5) / Made available in DSpace on 2018-06-13T17:14:14Z (GMT). No. of bitstreams: 1 santos_ls_dr_jabo.pdf: 1204964 bytes, checksum: 50ea21a5746571da15672c9df3679bda (MD5) Previous issue date: 2018-04-27 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Dentre as lagartas desfolhadoras mais importantes nos cultivos da soja no Brasil estão a Anticarsia gemmatalis e a Chrysodeixis includens. O objetivo deste trabalho foi determinar a flutuação populacional e a relação com fatores meteorológicos e a distribuição espacial de A. gemmatalis e de C. includens em cultivares de soja com diferentes ciclos de desenvolvimento, visando gerar informações sobre o comportamento dessas lagartas na cultura da soja e elaborar um plano de amostragem sequencial para a cultura da soja. Os experimentos foram conduzidos nos anos agrícolas 2013/14 e 2014/15 na FCAV/UNESP, Jaboticabal, SP. Foram selecionados três campos, e em cada um foi demarcada uma área de 8.000 m2, sendo cada área subdividida em 80 parcelas de 100 m2 (10 m x 10 m). As cultivares de soja utilizadas foram: SYN 1365 RR (precoce), M 7908 RR (média) e BRS Valiosa RR (tardia). As amostragens foram realizadas semanalmente pelo método da batida de pano, em 2 m de linha de plantas, registrando-se o número total de lagartas maiores que 1,5 cm de A. gemmatalis e C. includens. Para o estudo da flutuação populacional das espécies de lagartas da soja os resultados foram submetidos à analise estatística, efetuando-se correlação de Pearson, entre o número de espécies de lagartas e as variáveis meteorológicas, precipitação e temperatura. Para o estudo da dispersão foram utilizados os seguintes índices: razão variância/média, índice de Morisita, coeficiente de Green e o expoente k da distribuição binomial negativa. Para os estudos dos modelos de distribuição espacial foram testados os ajustes das distribuições de Poisson e binomial negativa. O plano de amostragem sequencial foi elaborado para os dados de lagartas maiores que 1,5 cm com base no Teste Sequencial da Razão da Máxima Verossimilhança, e foi utilizado o nível de controle de 40 lagartas maiores que 1,5 cm por pano de batida na cultura da soja. De acordo com os resultados da flutuação populacional, as maiores densidades populacionais de A. gemmatalis e C. includens foram observadas no estádio fenológico R1 da soja. A temperatura influenciou a variação da densidade populacional de C. includens no primeiro ano agrícola e a precipitação influenciou a população de ambas as lagartas nos dois anos agrícolas. A distribuição espacial de lagartas maiores que 1,5 cm foi agregada para todas as cultivares no ano agrícola com baixa incidência de lagartas e aleatória no ano agrícola com alta incidência de lagartas, com melhor ajuste à distribuição binomial negativa. No plano de amostragem sequencial, verificou-se um máximo de dez unidades amostrais para tomada de decisão de controle. / The most frequent leafhopper caterpillars on soybean crops in Brazil are Anticarsia gemmatalis and Chrysodeixis includens. The objective of this work was to study the population fluctuation and spatial distribution of A. gemmatalis and C. includens in soybean cultivars of different maturing cycles in order to help the development of a sequential sampling plan. The experiments were carried out in seasons 2013/14 and 2014/15 at FCAV / UNESP, Jaboticabal, SP. Three fields were selected, and on each one an area of 8.000 m² was marked and divided into 80 splits of 100 m² (10 m x 10 m). The soybean cultivars of different maturing cycles were: SYN 1365 RR (early), M 7908 RR (middle) and BRS Valiosa RR (late). Samples were taken weekly using the ground-shake method, in two m line of plants, where it was recorded the number of caterpillars A. gemmatalis and C. includens higher than 1.5 cm. The figures were plotted to demonstrate the population fluctuation between the mean data of insect pest infestation and the phenological stage of culture, and the influence of meteorological factors analyzed using correlation analysis. Insect dispersion in the area was evaluated using the following indexes: variance/mean ratio, Morisita’s index, Green’s coefficient, and the k exponent of negative binomial distribution. For studies of spatial distribution models of A. gemmatalis and C. includens, adjustments of Poisson distribution and negative binomial distribution were tested. The sequential sampling plan was developed for caterpillars higher than 1.5 cm based on the ratio of the Sequential Test Maximum Likelihood, and it was used the threshold levels of 40 and 20 caterpillars higher than 1.5 cm in soybean. According to the results of population fluctuation, the highest population densities of A. gemmatalis and C. includens were observed at the R1 soybean phenological stage. The temperature influenced the variation of population density of C. includens in the first agricultural year and the precipitation influenced the population of both caterpillars in the two agricultural years. The spatial distribution of caterpillars larger than 1.5 cm was aggregated for all cultivars in the agricultural year with low incidence of caterpillars and random in the agricultural year with high incidence of caterpillars, with better adjustment to the negative binomial distribution.In the sequential sampling plan, the maximum number of sample units expected for control of decision-making is around ten samples. / 870397/1997-4
25

Códigos identificadores em algumas classes de grafos / Identifying codes in some classes of graphs

Félix, Juliana Paula 19 February 2018 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-03-16T10:48:35Z No. of bitstreams: 2 Dissertação - Juliana Paula Félix - 2018.pdf: 1739140 bytes, checksum: 14e7528cefac5d3322e49131936f3c86 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-03-16T10:49:04Z (GMT) No. of bitstreams: 2 Dissertação - Juliana Paula Félix - 2018.pdf: 1739140 bytes, checksum: 14e7528cefac5d3322e49131936f3c86 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-03-16T10:49:04Z (GMT). No. of bitstreams: 2 Dissertação - Juliana Paula Félix - 2018.pdf: 1739140 bytes, checksum: 14e7528cefac5d3322e49131936f3c86 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-02-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work, we investigate the problem of finding identifying codes of minimum size in a variety of graph classes, such as trees corona products, Cartesian products and complementary prisms. For caterpillar trees, we show the minimum size of an identifying code on complete caterpillars, brooms and double brooms. We also prove a sharp upper bound for the general case. For coronas $K_n \circ \overline{K}_m$, we prove what is the minimum size of an identifying code. We demonstrate a sharp upper bound for an identifying code of the Cartesian product of a star and a path $K_{1,n} \square P_m$ and, when $n=3$, we conjecture that the limit proposed is minimum. We also find the minimum cardinality of an identifying code in the complementary prism of complete bipartite graphs and complete split graphs, among with other results: we demonstrate that the complementary prism graph $G\overline{G}$ is identifiable if, and only if, $G$ has at least two vertices; we find what is the smallest size possible of an identifying code of complementary prisms; we prove a sharp upper bound for an identifying code of the complementary prism $G\overline{G}$ of a connected graph $G$, showing that the set $C = V(G)$ is an identifying code with the size proposed and, finally, we determine the size of a minimum identifying code of the complementary prism of a complete bipartite graph, showing that it is an example of a graph that attains our upper bound. / Neste trabalho, investigamos o problema de se encontrar códigos identificadores de cardinalidade mínima em diversas classes de grafos, tais como árvores, produtos coronas, produtos Cartesianos e prismas complementares. Para árvores caterpillar, determinamos a cardinalidade mínima de um código identificador em caterpillars completo, grafos broom e broom duplo, e provamos um limite superior justo para caterpillars gerais. Para coronas, determinamos a cardinalidade mínima de um código identificador em $K_n \circ \overline{K}_m$. Para produtos Cartesianos, investigamos códigos identificadores em grafos $K_{1,n} \square P_m$, definimos um limite superior justo para o caso em que $n=3$ e um limite superior mais abrangente para o caso em que $n \geq 3$. Quando $n=3$, conjecturamos que o limite proposto é mínimo. Para prismas complementares de grafos, encontramos o tamanho de um código identificador mínimo em grafos bipartidos completos e grafos split completos. Para prismas complementares, obtivemos ainda outros resultados: demonstramos que um grafo prisma complementar $G\overline{G}$ é identificável se, e somente se, a ordem de $G$ é pelo menos dois; definimos o menor tamanho possível de um código identificador em um grafo $G\overline{G}$; determinamos um limite superior justo para o código identificador de um grafo conexo, mostrando também que seu conjunto de vértices é um conjunto identificador com o tamanho proposto e, finalmente, mostramos que o grafo bipartido completo é um exemplo de grafo que atinge a igualdade do limite superior apresentado.
26

Interactions Among Multiple Plastic Traits in Caterpillar Thermoregulation

Nielsen, Matthew Erik, Nielsen, Matthew Erik January 2016 (has links)
Adaptive phenotypic plasticity is a key mechanism by which organisms deal with variation in many different aspects of their environment. Adaptive plasticity can occur in any trait, from aspects of biochemistry and morphology to behaviors. Because so many different traits can be plastic, organisms often respond plastically to a given change in their environment, such as an increase in temperature, with adaptive changes in multiple traits. Nevertheless, how these different plastic responses interact with each other and evolve together has received little attention. My research addresses these potential interactions among plastic traits and proposes new hypotheses regarding the causes and consequences of these interactions. It does so by focusing on heat avoidance in the caterpillars of Battus philenor (the pipevine swallowtail) which involves two distinct plastic mechanisms. First, the caterpillars can change color when they molt, a form of morphological plasticity in which they develop a red color under high temperatures which cools them by absorbing less solar radiation. Second, when the caterpillars become too hot, they will leave their host to seek cooler thermal refuges, a case of behavior as a form of plasticity. In terms of function, I demonstrated through field research that these two responses to high temperatures are largely redundant. Behavior provides a much stronger and faster response than color change, and red coloration provides little additional cooling when on a refuge. Instead, the primary benefit of color change is that it reduces the use of refuge seeking behavior, allowing the caterpillars to stay on their hosts longer. Using laboratory experiments, I demonstrated that this change in the use of refuge-seeking behavior with color occurs because color changes the cue for the behavior, body temperature, rather having any effect on how the caterpillar responds to that cue. Alternatively, similar experiments on caterpillars of varying sizes show that developmental size change lowers the body temperature at which caterpillars leave their host, demonstrating a change in the response to the cue (although larger caterpillars are also warmer, so both mechanisms are likely relevant for how size changes the expression of behavior). All of my research to this point was conducted on the local population in southern Arizona, which experiences quite high temperatures, but B. philenor is also found in much cooler environments, such as the Appalachian Mountains. Given this variation in their thermal environment, I used common garden experiments to compare the capacity for color change and refuge-seeking among B. philenor caterpillars from across the species range. Both color change and refuge seeking not only occurred in all populations, but also had the same reaction norms, occurring at the same temperatures and to the same degree. This is particularly notable for color change, which is not observed in the wild in northeastern populations, and thus has persisted despite minimal if any use. Overall, I have shown that studies of plasticity need to account for plasticity in different traits as well as the interactions between these forms of plasticity. My research on B. philenor provides a model for how to address these interactions, which future research can extend to additional organisms and environmental circumstances.
27

Avaliação da eficácia do soro antilonômico na reversão da síndrome hemorrágica causada por contado com lagartas da Lonomia obliqua (Lepidoptera, Saturniidae)

Caovilla, Jairo José January 2003 (has links)
A síndrome hemorrágica causada por contato com lagartas da Lonomia obliqua tem alcançado proporções epidêmicas no sul do Brasil. O objetivo deste estudo foi avaliar a eficácia de diferentes doses do soro antilonômico (SALon) no tratamento de pacientes que tiveram contato com lagartas da Lonomia obliqua. Um ensaio clínico prospectivo, randomizado, duplo-cego foi realizado no hospital universitário São Vicente de Paulo de Passo Fundo, RS, Brasil. Entre janeiro de 2000 a março de 2002, 44 pacientes portadores de síndrome hemorrágica grau I e grau II foram randomizados em dois grupos: Grupo A: 22 pacientes que receberam uma dose de 10,5mg (três ampolas) de SALon; Grupo B: 22 pacientes que receberam uma dose de 17,5mg (cinco ampolas) de SALon. A eficácia do tratamento foi avaliada pelo tempo necessário para normalização dos fatores de coagulação sangüínea, freqüência de reações adversas e dias de hospitalização. Não houve diferença no quadro clínico e nas alterações laboratoriais entre os dois grupos. O tempo médio para normalizar o tempo de coagulação foi de 15,3 ± 6,6 h e de 19,1 ± 8 h nos grupos A e B, respectivamente (P = 0,09). A freqüência de reações adversas e o tempo de internação hospitalar foram semelhantes entre os dois grupos. O uso do soro antilonômico foi efetivo e bem tolerado. Doses substancialmente menores das preconizadas podem ser suficientes para reverter à síndrome hemorrágica causada pelo envenenamento por contato com lagartas da Lonomia obliqua. / The hemorrhagic syndrome caused by contact with Lonomia obliqua caterpillars has reached epidemic proportions in southern Brazil. This study aimed at assessing the efficacy of different dosages of an antilonomic serum (SALon) in the treatment of patients who had accidental contact with Lonomia obliqua caterpillars. A randomized, double-blinded, prospective clinical trial was conducted at São Vicente de Paulo Hospital, a tertiary hospital in Passo Fundo, Brazil. From January 2000 to April 2002, 44 patients with grade I or II hemorrhagic syndrome were randomly assigned to either group A (22 patients treated with 10,5mg total dose, 3 vials of SALon) or group B (22 patients treated with 17,5mg total dose, 5 vials of SALon). Treatment efficacy was assessed according to time necessary for blood coagulation to go back to normal, incidence of adverse reactions, and hospitalization time. There were no differences in clinical picture and laboratory findings between the two groups. Mean time for coagulation to go back to normal was 15.3±6.6 h and 19.1±8 h in groups A and B, respectively. Adverse reactions and hospitalization time were similar in both groups. SALon was effective and well tolerated. Results suggest that substantially smaller doses than those routinely prescribed may be sufficient for the treatment of envenoming by Lonomia caterpillars.
28

Efeito da aplicação de silicato de cálcio e magnésio no desenvolvimento biológico de Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) em milho (Zea mays) (Poaceae) / Effect of calcium and magnesium in biological development os Spodoptera frugiperda (JE Smith, 1797) (Lepidoptera: Noctuidae) on corn (Zea mays) (Poaceae)

Barbosa, Tiago Jorge de Araújo 05 October 2011 (has links)
The study was conducted to evaluate the effect of different doses of silicon, applied to the soil, in biological development of Spodoptera frugiperda (J. E. Smith, 1979) (Lepdoptera: Noctuidae). It was developed in two phases, the first one in a greenhouse and Laboratory of Entomology and the second one in a field, both at the Centre of Agricultural Sciences of Universidade Federal de Alagoas, Rio Largo, AL. The design experiment was completely randomized in blocks at random, for the first and second stages, respectively. Five were used in both treatments, which were represented by different doses of silicon (without application; 500kg.ha-1 of SiO2; 1.000kg.ha-1 of SiO2; 1.500kg.ha-1 of SiO2 and 2.000kg.ha-1 of SiO2) applied to the soil with calcium silicate and magnesium 10.5% silicon, divided into two applications. The first step tests were performed to evaluate resistance (in greenhouse and in the laboratory), with fisrts instar caterpillars from the creation of maintenance, in the first 24hours after the outbreak. The second step was performed in a total area of 128,5m², divided into four blocks, where we evaluated the injuries caused by the plague in four different seasons (15, 30, 45 and 60 days after plants emergence), the infestation and productivity. To evaluate injury, we used a grading scale proposed by CARVALHO (1970). The note data obtained from four evaluations, were transformed in and the medium subjected to the analysis of variance and compared by Tukey test at a significant level of 5%. For the results it is possible to end what to applications of silicate of calcium and magnesium in pots in house of vegetation, did not interfere in the number of instar and not even in the duration of the phase larval and pupal. However, all the treatments that received silicon interfere positively in the weight and length of caterpillars of S. frugiperda in the very development. The applications of silicate of calcium and magnesium, in furrow in the planting and in covering, do not interfere in the productivity and not even in the insults provoked for S. frugiperda in the culture of the corn. However, it was noticed that the percentage of infestation was small when it was used 500 kg.ha-1 of SiO2, to the 15 and 45 DAE. / Fundação de Amparo a Pesquisa do Estado de Alagoas / O estudo foi realizado visando avaliar o efeito de diferentes doses de silício, aplicado via solo, no desenvolvimento biológico de Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae). Foi desenvolvido em duas etapas, sendo a primeira em telado e no Laboratório de Entomologia e a segunda em campo, ambos no Centro de Ciências Agrárias da Universidade Federal de Alagoas, Rio Largo, AL. O delineamento experimental foi o inteiramente casualizado e em blocos ao acaso, para a primeira e a segunda etapas, respectivamente. Em ambas foram utilizados cinco tratamentos, os quais foram representados por diferentes doses de silício (sem aplicação; 500kg.ha-1 de SiO2; 1.000kg.ha-1 de SiO2; 1.500kg.ha-1 de SiO2 e 2.000kg.ha-1 de SiO2) aplicados via solo com silicato de cálcio e magnésio a 10,5% em silício, divididos em duas aplicações. Na primeira etapa foram realizados testes para avaliar o desenvolvimento biológico (em casa-de-vegetação e no laboratório), com lagartas de primeiro ínstar provenientes da criação de manutenção, nas primeiras 24 horas após a eclosão. A segunda etapa foi realizada em campo numa área total de 128,5m2, dividida em quatro blocos, onde foram avaliadas as injúrias provocadas pela praga, em quatro épocas diferentes (15, 30, 45 e 60 dias após a emergência das plantas), a infestação e a produtividade. Para avaliação de injúrias, utilizou-se uma escala de notas proposta por CARVALHO, (1970). Os dados das notas, obtidas de quatro avaliadores, foram transformados em e as médias submetidas à análise de variância e comparadas pelo teste de Tukey ao nível de significância de 5%. Pelos resultados pode-se concluir que a aplicações de silicato de cálcio e magnésio em vasos em casa-de-vegetação, não interferiu no número de ínstares e nem na duração da fase larval e pupal. No entanto, todos os tratamentos que receberam silício interferem positivamente no peso e comprimento de lagartas de S. frugiperda no máximo desenvolvimento. As aplicações de silicato de cálcio e magnésio, em sulco no plantio e em cobertura, não interferem na produtividade e nem nas injúrias provocadas por S. frugiperda na cultura do milho. No entanto, observou-se que a porcentagem de infestação foi menor quando se utilizou 500kg.ha-1 de SiO2, aos 15 e 45 DAE.
29

Phenotypic plasticity and susceptibility to pathogens in Anticarsia gemmatalis (Lepidoptera: Noctuidae) / Plasticidade fenotípica e susceptibilidade a patógenos em Anticarsia gemmatalis (Lepidoptera: Noctuidae)

Silva, Farley William Souza 17 July 2010 (has links)
Made available in DSpace on 2015-03-26T13:30:31Z (GMT). No. of bitstreams: 1 texto completo.pdf: 586923 bytes, checksum: 24da6077dcd7d4efe5e55cbc10a1c8a1 (MD5) Previous issue date: 2010-07-17 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Prophylactic investment in defense from parasites and pathogens involves a high cost. Thus, it is expected that organisms use this only when required, for example, when at high population densities, where the risk of parasite or pathogen transmission may be increased. If the infection risk for individuals increases with host density, it is expected that hosts subject to high densities evolve mechanisms of resistance, as proposed by the "density-dependent prophylaxis" (DDP) hypothesis. Tests of these predictions have been conducted in a wide range of insects, both in comparative studies, where species live at different densities and in experimental studies, where the host density is manipulated. In the latter case, however, tests have mostly been restricted to gregarious insects that present density-dependent phase polyphenism. For this reason, we chose to test these predictions in a solitary species, Anticarsia gemmatalis (Lepidoptera: Noctuidae), that presents features of gregarious insects. We showed a prophylactic response to increased conspecific densities in A. gemmatalis larvae. When at increased larval density, with the accompanying phenotypic change, there is a greater degree of encapsulation of the nylon filament, higher hemocyte numbers, but lower melanization. We showed that this response was a function, not only the density per se, but also of the contact among conspecifics. Thus, we showed that DDP is a more common phenomenon thatpreviously thought, occurring even in a species known as being solitary. Furthermore, the prophylactic responses in this species are not only densitydependent, but are more specifically contact- dependent. This may provide a new context to the DDP hypothesis; in which even solitary species may present plastic prophylactic responses at crowded moments. / Investimentos profiláticos em defesa a parasitas e patógenos envolvem um custo. Assim, é esperado que organismos os usem somente quando requeridos, por exemplo quando em altas densidades populacionais, onde o risco de transmissão de parasitas e patógenos pode ser aumentado. Se o risco para o individuo aumenta com a densidade populacional, é esperado que hospedeiros evoluam mecanismos de resistência, como proposto pela hipótese da "profilaxia densidade-dependente" (PDD). Testes dessas predições têm sido conduzidos em uma gama de insetos, seja em estudos comparativos onde espécies vivem em diferentes densidades ou em estudos experimentais onde a densidade do hospedeiro é manipulada. Nesse caso, no entanto, testes têm sido restritos a insetos gregários que apresentam o polifenismo de fase densidade-dependente. Por isso, nós escolhemos testar essas predições em uma espécie solitária que apresenta características de insetos gregários, Anticarsia gemmatalis (Lepidoptera: Noctuidae). Neste estudo, nós mostramos as repostas profiláticas de larvas de A. gemmatalis ao aumento da densidade de co-específicos. Quando em maiores densidades larvais, acompanhada de mudança fenotípica, há um maior grau de encapsulação do filamento de nilon, aumento no número de hemócitos, mas menor melanização. Nós mostramos que essas respostas foram função não só densidade per se, mas também do contato entre co-específicos. Dessa forma, nós mostramos que a PDD é um fenômeno mais comum que se pensava, ocorrendo mesmo em espécies conhecidas como sendo solitárias. Além disso, as respostas profiláticas nessa espécie não são só densidade-dependente, mas mais especificamente, contato-dependente. Isto fornece um novo contexto a essa hipótese, já que mesmo espécies solitárias podem apresentar respostas profiláticas ao aumento da densidade populacional.
30

Bioecologia e controle microbiano de sarsina violascens (Herrich-schaeffer, 1856) (Lepidoptera: Lymantriidae) em Eucalyptus spp

Winckler, Daniela Cristina Firmino [UNESP] 03 July 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:34:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-03Bitstream added on 2014-06-13T18:45:52Z : No. of bitstreams: 1 winckler_dcf_dr_botfca.pdf: 826861 bytes, checksum: 0065d6bc13ca46069b7bee48b655a961 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A espécie Sarsina violascens (Herrich–Schaeffer, 1856) (Lepidoptera: Lymantriidae) é relatada como praga primária em plantios de eucalipto e teve sua primeira ocorrência registrada em 1975. No período de 2006 a 2009 houve grandes surtos dessa praga, causando desfolhamento intenso em plantios de eucalipto no norte da Bahia. Apesar dos estudos feitos no passado terem considerado espécies de eucalipto, há pouca informação sobre a suscetibilidade de clones híbridos de eucalipto à mariposa violácea. O presente trabalho teve por objetivo avaliar a biologia de S. violascens em diferentes espécies e híbridos de eucalipto e em diferentes temperaturas, além de avaliar a eficiência de entomopatógenos no controle de S. violascens. No experimento 1 a biologia de S. violascens foi determinada nas espécies Eucalyptus grandis, E. urophylla e dois híbridos de E. grandis x E. urophylla (‘urograndis’). Os parâmetros avaliados foram duração e viabilidade dos estágios larval, pupal, adulto e de ovo e do ciclo total. No experimento 2 foi selecionada a espécie E. urophylla como padrão e avaliou-se o efeito de diferentes temperaturas (18, 22, 26 e 30oC) no desenvolvimento de S. violascens, avaliando-se os mesmos parâmetros anteriores. Os resultados obtidos no experimento 1 revelaram que E. urophylla ofereceu melhores condições para odesenvolvimento de S. violascens, com maior viabilidade larval (85,3 %), pupal (78,7 %) e de ovos (72,6 %), e menor duração do ciclo total (54,4 dias). A espécie E. grandis foi considerada a menos adequada ao desenvolvimento de S. violascens, revelando baixas viabilidades larval (29,2 %) e pupal (28,9 %). Os resultados obtidos com os dois híbridos foram intermediários comparativamente com as espécies testadas. No experimento 2 as temperaturas de 18, 22 e 26°C foram adequadas para o desenvolvimento e reprodução de S. violascens, com alta viabilidade... / Defoliator lepidopterous are one of the main Eucalyptus pest groups in Brazil. There are records of caterpillars outbreaks since 1940, with important occurrences during 1980’s to 1990’s. The species Sarsina violascens (Herrich–Schaeffer, 1856) (Lepidoptera: Lymantriidae), named as violet moth, is related as pest in eucalypts plantations since 1975 and during 2006 to 2009, this species has occurred in outbreaks, causing intense defoliation in eucalypt plantations in Northern Bahia, Brazil. Despite studies in the past have considered species of eucalyptus, there is little information about susceptibility of Eucalyptus hybrid clones to violet moth. This study aimed to determine the biology of S. violascens in different species and hybrids of eucalyptus and in different temperatures. The insects were observed diary to evaluate life cycle in different species of eucalyptus (experiment 1) and in different temperatures (experiment 2). In experiment 1 were tested the following species: Eucalyptus grandis, E. urophylla and two hybrids of E. grandis x E. urophylla (‘urograndis’). The parameters evaluated were: duration and viability of larvae, pupae, adult and eggs phases and total life cycle. In experiment 2 was chose the species E. urophylla as standard and evaluated the effect of temperatures of 18, 22, 26 and 30oC, considering the same previous parameters. The results obtained in experiment 1 showed that E. urophylla offered better conditions to S. violascens development and reproduction, due the higher larvae, pupae and eggs viability, and shorter total life cycle duration. The species E. grandis was considered as less adequate to S. violascens development and reproduction, with low larvae and pupae viability. To the two hybrid clones, the results were intermediary comparatively with tested species. In experiment 2 temperature of 18°C showed the most adequate to S. violascens... (Complete abstract click electronic access below)

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