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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.
1

Stage-structured insect population models of larval competition

Jones, A. E. January 1986 (has links)
No description available.
2

The population ecology of two insect pathogens

Knell, Robert James January 1996 (has links)
No description available.
3

Utilização da radiação gama do Cobalto-60 como tratamento quarentenário de plantas medicinais, aromáticas e condimentares desidratadas infestadas por lasioderma serricorne (fabricius, 1792) (coleoptera, anobiidae) e plodia interpunctella (hubner, 1813) (lepidoptera, pyralidae) / UTILISATION OF THE GAMMA RADIATION OF COBALTO - 60 AS QUARANTINE TREATMENT OF THE MEDICINAL PLANT, AROMATIC AND SEASONING PLANTS DEHYDRATED INFESTED BY LASIODERMA SERRICORNE (FABRICIUS, 1792) (COLEOPTERA, ANOBIIDAE) E PLODIA INTERPUNCTELLA (HUBNER, 1813) (LEPIDOPTERA, PYRALIDAE).

Juliana Nazaré Alves 13 July 2007 (has links)
A pesquisa teve como objetivo a utilização da radiação gama do Cobalto-60 como tratamento quarentenário de plantas medicinais, aromáticas e condimentares desidratadas infestadas por Lasioderma serricorne e Plodia interpunctella determinando as doses desinfestantes atendendo o critério de não emergência de adultos das espécies em estudo e analisando através da Cromatografia de Camada Delgada os efeitos da radiação gama do Cobalto-60 sobre o princípio ativo dos substratos desidratados de Chamomilla recutita, Pimpinella anisum, Origanum vulgare, Cymbopogon citratus, Ocimum basilicum e Thymus vulgaris. O trabalho foi desenvolvido no Laboratório de Inseticidas do Instituto Biológico em São Paulo no período de agosto de 2005 a junho de 2007. A fonte de radiação gama utilizada foi um irradiador experimental de Cobalto-60, modelo Gamacell 220, localizado no Instituto de Pesquisas Energéticas e Nucleares ? IPEN, localizado em São Paulo. No período de 30 dias após a irradiação das amostras avaliou-se o número de adultos emergidos de Lasioderma serricorne e Plodia interpunctella, utilizando os dados de mortalidade para a análise de Probit. Obteve-se 100% de não emergência de adultos de Lasioderma serricorne com a dose de 2,00 kGy e 100% de não emergência de adultos de Plodia interpunctella com a dose de 2,25 kGy. A Análise Cromatográfica de Camada Delgada efetuada não revelou diferença na composição química dos substratos analisados. / The research had as objective the use of the gamma radiation of the Cobalto-60 as quarantine treatment of the medicinal plant, aromatic and seasoning plants dehydrated infested by Lasioderma serricorne and Plodia interpunctella determining the desinfestation doses to attend the criterion in the not emergency of adults of the species in study and analysing through the Chromatography of Thin Layer the effect of the gamma radiation of the cobalto-60 on the active principle of extract dehydrated of Chamomilla recutita, Pimpinella anisum, Origanum vulgare, Cymbopogon citratus, Ocimum basilicum and Thymus vulgaris. The work was developed in the Laboratório de Inseticidas in the Instituto Biológico in São Paulo in the period of August of 2005 the June of 2007. The radiation source used gamma was an experimental irradiador of Cobalto-60, model Gamacell 220, located in the Instituto de Pesquisas Energéticas e Nucleares - IPEN, located in São Paulo. In the period of 30 days after the irradiation of the samples evaluated the number of adults emerged of Lasioderma serricorne and Plodia interpunctella, using the data of mortality for the analysis of Probit. Obtained 100% of not emergency of adults in the Lasioderma serricorne with the dose of 2,00 kGy and 100% of not emergency of adults in the Plodia interpunctella with the dose of 2,25 kGy. The Chromatographic Analysis of Thin Layer was to evaluate did not show chemical differences in the extracts analysed.
4

Detecção de inibidores de tripsina em genótipos de gergelim visando controle de Plodia interpunctella

Gomes, Gessica Laize Berto 28 February 2014 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-03-09T13:28:58Z No. of bitstreams: 1 PDF - Géssica Laize Berto Gomes.pdf: 960450 bytes, checksum: 01f35541007decb425986338cf77d27a (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-07-21T21:00:52Z (GMT) No. of bitstreams: 1 PDF - Géssica Laize Berto Gomes.pdf: 960450 bytes, checksum: 01f35541007decb425986338cf77d27a (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-07-21T21:01:00Z (GMT) No. of bitstreams: 1 PDF - Géssica Laize Berto Gomes.pdf: 960450 bytes, checksum: 01f35541007decb425986338cf77d27a (MD5) / Made available in DSpace on 2016-07-21T21:01:00Z (GMT). No. of bitstreams: 1 PDF - Géssica Laize Berto Gomes.pdf: 960450 bytes, checksum: 01f35541007decb425986338cf77d27a (MD5) Previous issue date: 2014-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The Brazilian production of grains has grown every year, transforming Brazil in one of the main cereals and oilseeds producers. However, the post-harvest losses are huge, causing production loss by the inadequacy of storage, especially in order of pest occurrence. In the case of sesame, there has been a marked occurrence of P. interpuctella, which attack stored grains accompanied by other pests causing economic damage to the crop. With this, the Breeding Program Sesame Embrapa Cotton seeks alternatives to control these pests by genotypes that express high levels of protein inhibitors (PIs) with ability to inhibit proteolytic digestive enzymes of insects. The objective of this study was to detect trypsin inhibitors in genotypes of sesame (S. indicum L.) with potential use in biotechnological applications and programs to improve the species, aiming selection of genotypes resistant to stored grain pests, so we proceeded to study PIs in 10 sesame genotypes belonging to the Active Germplasm Bank at Embrapa Cotton. The total protein extracts of accessions were extracted and tested in vitro with bovine pancreatic trypsin (BPT) and intestinal homogenate of larvae of P. interpuctella. After selection of the most promising genotypes, we proceeded to a protein fractionation with ammonium sulfate. The protein fractions obtained were analyzed for inhibitory activity with BPT and intestinal homogenate of larvae of P. interpuctella, and yet, as the thermal stability and hydrogen ion and bioassays with P. interpuctella. Data were analyzed by Tukey test at 5% of probability. The results showed the presence of trypsin inhibitors in the total protein extracts of 10 sesame genotypes, ranging from 51% to 90% inhibition, among which, the BRS-SEDA, CNPA G3 and CNPA G4 stood out with 87%, 88% and 90% inhibition, respectively. These genotypes inhibitory activity have been demonstrated for the intestinal homogenate of larvae of P. interpuctella, with inhibition between 60% and 76%. The fractions F2 of the three genotypes were relatively stable to changes in temperature and pH. In the bioassay, the larvae of P. interpuctella. were susceptible to protein extracts of the three genotypes of sesame, with a maximum of 83% mortality of larvae in different strengths with total protein extracts and 58% in fractions F2, however, did not observe statistically a significant difference between genotypes. In this regard, BRS-SEDA, CNPA G3 and CNPA G4 have protein inhibitors that can prevent the development of P. interpuctella, suggesting candidates with potent insecticidal properties to control stored grain pests. / A produção brasileira de grãos tem crescido a cada ano levando o Brasil a um dos principais produtores de cereais e oleaginosas. No entanto, as perdas na pós-colheita são enormes provocando uma redução da produção em função do controle inadequado no armazenamento, especialmente em função da ocorrência de pragas. No caso do gergelim, tem havido uma ocorrência acentuada de P. interpuctella, que ataca os grãos armazenados acompanhado de outras pragas, causando danos econômicos à cultura. Com isto, o Programa de Melhoramento Genético de Gergelim da Embrapa Algodão busca alternativas para controlar essas pragas, por meio de genótipos que expressem altos níveis de inibidores proteicos (IPs) com capacidade de inibir enzimas proteolíticas digestivas de insetos. Objetivou-se com este trabalho detectar inibidores de tripsina em genótipos de gergelim (Sesamum indicum L.) com potencial uso na aplicação biotecnológica e no programa de melhoramento da espécie, visando seleção de genótipos resistentes a pragas de grãos armazenados. Assim, procedeu-se o estudo de IPs em 10 genótipos de gergelim, pertencentes ao Banco Ativo de Germoplasma da Embrapa Algodão. Os extratos proteicos totais dos acessos foram extraídos de sementes de gergelim e testados in vitro com tripsina pancreática bovina (TPB) e homogenato intestinal de larvas de P. interpuctella. Após seleção dos genótipos mais promissores, procedeu-se um fracionamento proteico com sulfato de amônia. As frações proteicas obtidas foram analisadas quanto a atividade inibitória com TPB e homogenato intestinal de larvas de P. interpuctella, e ainda, quanto a estabilidade térmica e hidrogeniônica e em bioensaios com P. interpuctella. Os dados foram analisados pelo teste de Tukey a 5% de probalibilidade. Os resultados obtidos mostraram a presença de inibidores de tripsina nos extratos proteicos totais dos 10 genótipos de gergelim, com variação de 51% a 90% de inibição, dentre os quais, o BRS-SEDA, CNPA G3 e CNPA G4 se destacaram com 87%, 88% e 90% de inibição, respectivamente. Nesses genótipos foram evidenciadas atividade inibitória para o homogenato intestinal de larvas de P. interpuctella, com inibição entre 60% e 76%. As frações F2 dos três genótipos foram relativamente estáveis às variações de temperatura e pH. No ensaio biológico, as larvas de P interpuctella mostraram-se suscetíveis aos extratos proteicos dos três genótipos de gergelim, com mortalidade máxima de 83% das larvas em diferentes dosagens com extratos proteicos totais e 58% nas frações F2, contudo, estatisticamente não observou-se diferença significativa entre os genótipos. Neste aspecto, os genótipos BRS-SEDA, CNPA G3 e CNPA G4 possuem inibidores proteicos capazes de impedir o desenvolvimento P. interpuctella, o que sugere potentes candidatos com propriedades inseticidas no controle de pragas de grãos armazenados.
5

Management of Indian meal moth and maize weevil in stored popcorn using approved grain protectants

Gao, Nan January 1900 (has links)
Master of Science / Department of Grain Science and Industry / Subramanyam Bhadriraju / Spinosad, methoprene, deltamethrin, and deltamethrin plus methoprene, are approved in the United States for treating popcorn. The Indian meal moth, Plodia interpunctella (Hübner), and maize weevil, Sitophilus zeamais (Motschulsky) are two stored-product insects found in popcorn. The efficacy of spinosad and methoprene against P. interpunctella in popcorn were determined in laboratory and field studies. In the laboratory study, eggs (to represent first instars), third, and fifth instars of the laboratory strain of P. interpunctella were exposed to 0.7, 1.4, 2.8 ppm methoprene and 1 ppm spinosad treated popcorn, respectively, to assess larval or adult emergence. In the field study, untreated and treated popcorn samples were placed in vinyl mesh pouches with two mesh-opening sizes and were buried 5 cm below popcorn surface. Pouches with large mesh-opening were used to monitor natural insect infestation between May to October, 2017. Pouches with small mesh-opening were used to conduct laboratory bioassays to evaluate adult emergence of P. interpunctella from eggs after exposed to treated popcorn. Probe traps, food- and pheromone-baited traps, and sticky traps were used to monitor insects in storage bins and cleaning processing facility. The laboratory study showed that there was no P. interpunctella adults emerged from eggs, third, and fifth instars in methoprene treated popcorn during 6 month storage. However, methoprene did not reduce egg-to-larval survival. Larval and adult emergence in the spinosad treated popcorn was significantly lower than controls. Field study showed that there was no adult emergence in methoprene treated popcorn in most cases, and significantly lower adult emergence in spinosad treated popcorn compare to control. P. interpunctella larva was the major insect found in large pouches. The red flour beetle, Tribolium castaneum (Herbst), and P. interpunctella were primary insect species captured by probe traps, food- and pheromone-baited traps and sticky traps over the six months’ study. These results suggested that methoprene could reduce P. interpunctella adult emergence. Spinosad also effectively suppressed the infestation of P. interpunctella. The field strain of S. zeamais was exposed to spinosad (1 ppm), methoprene (0.7, 1.4, 2.8 ppm), deltamethrin (0.5, 1.0 ppm), and deltamethrin plus methoprene (0.5+1.25, 1.0+2.5 ppm) treated popcorn, respectively, for 1 to 336 h exposure time. Mortality was assessed at 0, 7, 14, and 21 d after transferring to clean popcorn except for methoprene treatments which only counted mortality at 0 d. Progeny and adult emergence were counted after 42 d incubation in clean or original popcorn, respectively. All insecticides showed no delay toxicity against S. zeamais adults. Spinosad caused 100% mortality of S. zeamais after 336-h exposure. Complete progeny reduction and highest adult emergence reduction at 168 h exposure. The highest mortality of S. zeamais was 67.1 and 70.5% in deltamethrin and deltamethrin plus methoprene treated popcorn, respectively. Methoprene showed limited efficacy against S. zeamais including low mortality, progeny reduction and high adult emergence. These results indicated that spinosad was effective against S. zeamais. It is necessary to combine other insecticides with deltamethrin and methoprene to control field strain of S. zeamais in stored popcorn.
6

Utilização da radiação gama do Cobalto-60 como tratamento quarentenário de plantas medicinais, aromáticas e condimentares desidratadas infestadas por lasioderma serricorne (fabricius, 1792) (coleoptera, anobiidae) e plodia interpunctella (hubner, 1813) (lepidoptera, pyralidae) / UTILISATION OF THE GAMMA RADIATION OF COBALTO - 60 AS QUARANTINE TREATMENT OF THE MEDICINAL PLANT, AROMATIC AND SEASONING PLANTS DEHYDRATED INFESTED BY LASIODERMA SERRICORNE (FABRICIUS, 1792) (COLEOPTERA, ANOBIIDAE) E PLODIA INTERPUNCTELLA (HUBNER, 1813) (LEPIDOPTERA, PYRALIDAE).

Alves, Juliana Nazaré 13 July 2007 (has links)
A pesquisa teve como objetivo a utilização da radiação gama do Cobalto-60 como tratamento quarentenário de plantas medicinais, aromáticas e condimentares desidratadas infestadas por Lasioderma serricorne e Plodia interpunctella determinando as doses desinfestantes atendendo o critério de não emergência de adultos das espécies em estudo e analisando através da Cromatografia de Camada Delgada os efeitos da radiação gama do Cobalto-60 sobre o princípio ativo dos substratos desidratados de Chamomilla recutita, Pimpinella anisum, Origanum vulgare, Cymbopogon citratus, Ocimum basilicum e Thymus vulgaris. O trabalho foi desenvolvido no Laboratório de Inseticidas do Instituto Biológico em São Paulo no período de agosto de 2005 a junho de 2007. A fonte de radiação gama utilizada foi um irradiador experimental de Cobalto-60, modelo Gamacell 220, localizado no Instituto de Pesquisas Energéticas e Nucleares ? IPEN, localizado em São Paulo. No período de 30 dias após a irradiação das amostras avaliou-se o número de adultos emergidos de Lasioderma serricorne e Plodia interpunctella, utilizando os dados de mortalidade para a análise de Probit. Obteve-se 100% de não emergência de adultos de Lasioderma serricorne com a dose de 2,00 kGy e 100% de não emergência de adultos de Plodia interpunctella com a dose de 2,25 kGy. A Análise Cromatográfica de Camada Delgada efetuada não revelou diferença na composição química dos substratos analisados. / The research had as objective the use of the gamma radiation of the Cobalto-60 as quarantine treatment of the medicinal plant, aromatic and seasoning plants dehydrated infested by Lasioderma serricorne and Plodia interpunctella determining the desinfestation doses to attend the criterion in the not emergency of adults of the species in study and analysing through the Chromatography of Thin Layer the effect of the gamma radiation of the cobalto-60 on the active principle of extract dehydrated of Chamomilla recutita, Pimpinella anisum, Origanum vulgare, Cymbopogon citratus, Ocimum basilicum and Thymus vulgaris. The work was developed in the Laboratório de Inseticidas in the Instituto Biológico in São Paulo in the period of August of 2005 the June of 2007. The radiation source used gamma was an experimental irradiador of Cobalto-60, model Gamacell 220, located in the Instituto de Pesquisas Energéticas e Nucleares - IPEN, located in São Paulo. In the period of 30 days after the irradiation of the samples evaluated the number of adults emerged of Lasioderma serricorne and Plodia interpunctella, using the data of mortality for the analysis of Probit. Obtained 100% of not emergency of adults in the Lasioderma serricorne with the dose of 2,00 kGy and 100% of not emergency of adults in the Plodia interpunctella with the dose of 2,25 kGy. The Chromatographic Analysis of Thin Layer was to evaluate did not show chemical differences in the extracts analysed.
7

Avalia??o da a??o bioinseticida de SBTI e vicilina de Erythrina velutina em enzimas digestivas e membrana peritr?fica de larvas de Plodia interpunctella (Lepidoptera: Pyralidae)

Amorim, Ticiana Maria L?cio de 28 September 2007 (has links)
Made available in DSpace on 2014-12-17T14:03:45Z (GMT). No. of bitstreams: 1 TicianaMLA.pdf: 543419 bytes, checksum: 8d1c551389143e2634c1d0451175ecef (MD5) Previous issue date: 2007-09-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Plodia interpunctella (Indian meal moth) is a cosmopolitan pest that attacks not only a wide range of stored grain as well other food products. Due to its economic importance several researches have focused in a method with ability to control this pest with few or no damage to the environment. The study of digestive enzymes inhibitors, lectins and chitin-binding proteins, has often been proposed as an alternative to reduce insect damage. In this study we report the major classes of digestive enzymes during larval growth in P. Interpunctella, being those proteinases actives at pH 9.5 and optimum temperature of 50 oC to both larvae of the 3rd instar and pre-pupal stage of development. In vitro and zymogram assays presented the effects of several inhibitors, such as SBTI, TLCK and PMSF to intestinal homogenate of 3rd instar larvae of 62%, 92% and 87% of inhibition and In pre-pupal stage of 87%, 62 % and 55% of inhibition, respectively. Zymograms showed inhibition of two low molecular masses protein bands by TLCK and that in presence of SBTI were retarded. These results are indicative of predominance of digestive serine proteinases in gut homogenate from Plodia interpunctella larvae. This serine proteinase was then used as a target to evaluate the effect of SBTI on larvae in in vivo assay. Effect of SBTI on mortality and larval mass was not observed at until 4% of concentration (w/w) in diets. Chitin, another target to insecticidal proteins, was observed by chemical method. Moreover, optic microscopy confirmed the presence of a peritrophic membrane. Established this target, in vivo effect of EvV, a chitin binding vicilin, evaluated during the larval development of P. interpunctella and was obtained a LD50 of 0,23% and WD50 of 0,27% to this protein. Mechanism of action was proposed through of the in vivo digestibility of EvV methodology. During the passage through the larval digestive tract was observed that EvV was susceptible to digestive enzymes and a reactive fragment, visualized by Western blotting, produced by digestion was recovered after dissociation of the peritrophic membrane. The bound of EvV to peritrophic membrane was confirmed by immunohystochemical assays that showed strong immunofluorescent signal of EvV-FITC binding and peritrophic membrane. These results are a indicative that vicilins could be utilized as potential insecticide to Plodia interpunctella and a control methods using EvV as bioinsecticide should be studied to reduce lost caused by storage insect pests / Plodia interpunctella (tra?a-indiana-da-farinha) ? uma praga cosmopolita que ataca n?o somente uma ampla gama de produtos armazenados, mas tamb?m outros produtos aliment?cios. Devido a sua import?ncia econ?mica v?rias pesquisas t?m sido realizadas com o intuito de identificar um m?todo capaz de controlar esta praga sem danos ao ambiente. O estudo de inibidores de enzimas digestivas, lectinas e prote?nas que se ligam ? quitina tem sido proposto como uma alternativa para controlar o dano causado por estes insetos. Neste estudo alvos espec?ficos para inibidores de enzimas e prote?nas ligantes ? quitina foram identificados nas larvas desta praga. Para isso, durante o desenvolvimento de larvas de P. interpunctella as classes de enzimas digestivas alvos foram identificadas por ensaios de atividade in vitro e SDS-PAGE, pH e temperatura ?timos avaliados para a indica??o de poss?veis prote?nas inibidoras para a principal classe de proteinase detectadas no intestino das larvas. Outro alvo para prote?nas delet?rias foi indicado pela identifica??o da membrana peritr?fica por ensaios qu?micos de detec??o de quitina e por microscopia de luz. Durante o per?odo de desenvolvimento as larvas de P. interpunctella, alimentadas com uma dieta baseada em baga?o de cana, passaram por 5 ?nstares e pelo est?gio pr?-pupal. A maior atividade proteol?tica (UA/intestino) foi detectada no est?gio pr?-pupal, enquanto que a maior atividade proteol?tica espec?fica (UA/mg prote?na) foi observada no terceiro ?nstar, utilizando azocase?na como substrato a pH 9,5 e a 50?C. A inibi??o das proteinases presentes no homogenato intestinal de larvas de terceiro ?nstar foi mais evidente quando inibidores de proteinases ser?nicas (SBTI, TLCK e PMSF, com 96%, 89% e 20% de inibi??o, respectivamente) foram utilizados nos ensaios. No est?gio pr?-pupal, a maior inibi??o observada foi com SBTI (96%), TLCK (81 %) e TPCK (20%), indicando a predomin?ncia de atividade enzim?tica de proteinases ser?nicas a pH 9,5 no intestino de Plodia interpunctella. Por zimograma foi observada inibi??o de bandas de menor massa molecular por TLCK e um atraso na corrida eletrofor?tica dessas bandas causado por SBTI. Quando avaliado o efeito in vivo de SBTI no desenvolvimento larval, n?o foi observada mortalidade e nem efeito na massa das larvas sobreviventes. Estabelecido o segundo alvo de atua??o, baseado na liga??o ? quitina, bioensaios usando a vicilina EvV foram realizados, onde um LD50 de 0,23% e um WD50 de 0,27% foram estabelecidos para esta prote?na delet?ria. O mecanismo de a??o foi verificado por ensaios de digestibilidade de EvV durante a passagem pelo trato intestinal larval, sendo observado o envolvimento de um fragmento reativo, observado por imunodetec??o, no efeito delet?rio da vicilina. A liga??o de EvV ? membrana peritr?fica foi comprovada atrav?s de ensaios de imunohistoqu?mica. Estes resultados apontam para uma vicilina ligante ? quitina que pode vir a ser utilizada como bioinseticida para Plodia interpunctella
8

Inapparent and vertically transmitted infections in two host-virus systems

Grunnill, Martin David January 2015 (has links)
Despite the advances made since the advent of germ theory, infectious diseases still wreak havoc on human societies, not only affecting us directly but impacting the crops and livestock upon which we rely. Infectious diseases also have dramatic effects on wildlife ecology. Therefore research into infectious diseases could not only directly lead to the improvement and saving of human lives, but aid in food security and the conservation of many wildlife species. Of vital importance in understanding the ecology of infectious diseases are the mechanisms by which they persist in host populations. One possible mechanism is vertical transmission: the transmission of a pathogen from a parent to its offspring as a result of the process of host reproduction. Another possible mechanism is inapparant infections, where an infected host does not display symptoms. Focusing on dengue fever and the Plodia interpunctella granulovirus laboratory system, this PhD thesis looks at the role these two mechanisms play on the persistence of two viral infections and their ecology. Regarding the Plodia interpunctella granulovirus (PiGV) low host food quality led to greater detection of vertically transmitted inapparant PiGV, but did not lead to its activation to an apparent form. Host inbreeding did not lead to vertically transmitted inapparant PiGV’s activation, nor had an effect on its vertical transmission. The vertical infection rate of PiGV was very low. I would therefore suggest that it may be better to use an insect virus system with a higher rate of vertical infection in future research into vertically transmitting inapparent infections. Regarding dengue virus I conclude that vertical transmission is not likely to play a role in the persistence of this virus. However modelling work found that inapparent infections could provide dengue viruses with a means of persistence and should be subject to further research.
9

Avaliação dos efeitos da radiação por feixe de elétrons na resistência de embalagens a Lasioderma serricorne, Plodia interpunctella e Sitophilus zeamais / Radiation effects evaluation for electrons sheaf in packages resistance in a Lasioderma serricorne, Plodia interpunctella and Sitophilus zeamais

Alves, Juliana Nazaré 16 August 2011 (has links)
As pragas de produtos armazenados constituem um problema para o homem, depreciando produtos e causando prejuízos econômicos. Dentre estas pragas temos o Lasioderma serricorne (F. 1792), Sitophilus zeamais (M. 1855) e Plodia interpunctella (H. 1813) conhecidos por infestar produtos armazenados como: grãos, farelos, farinhas, café, fumo, frutas secas e especiarias. Essas pragas perfuram e adentram as embalagens, ovipositando sobre o substrato. Neste contexto a embalagem desempenha um papel fundamental, impedindo o contato e proliferação de pragas no produto acondicionado. Assim, para proteger o produto acondicionado e prolongar a sua vidaútil a embalagem deve apresentar boa resistência mecânica à tração e à perfuração, boa selabilidade, boas propriedades de barreira e não transferir odores nem sabores estranhos ao produto acondicionado. A radiação ionizante pode causar mudanças estruturais nos materiais poliméricos de embalagens, essas mudanças são causadas pelos processos de cisão e reticulação das cadeias poliméricas. Estes são processos concorrentes e a predominância de um sobre o outro depende da estrutura química do polímero, das condições da irradiação e de fatores específicos do material que irá absorver a energia. Este trabalho teve o objetivo de avaliar as mudanças nas propriedades mecânicas de estruturas de embalagem utilizadas para armazenar granola, barra de cereais e macarrão, bem como suas resistências a perfuração por L. serricorne, P. interpunctella e S. zeamais, quando submetidas a radiação por feixe de elétrons. Na metodologia foram utilizadas cinco estruturas de embalagem comercialmente utilizadas para armazenar granola, barra de cereais e macarrão compostas por (Polipropileno bi-orientado metalizado/Polipropileno bi-orientado coextrusado - BOPPmet/BOPP 50 &mu;m), (Polipropileno bi-orientado/Polipropileno - BOPP/PP 50 &mu;m), Poli(tereftalato de etileno) metalizado/Polipropileno bi-orientado coextrusado - PETmet/BOPP 32 &mu;m), Poli(tereftalato de etileno)/Polipropileno - PET/PP1 72 &mu;m) e Poli(tereftalato de etileno)/Polipropileno - PET/PP2 32 &mu;m). As estruturas de embalagens foram submetidas à doses de radiação entre 0, 10, 20 e 60 kGy, em um acelerador de elétrons de 1,5 MeV, 25 mA e 37,5 kW, à taxa de dose de 11,22 kGy/s, temperatura ambiente e presença de ar. Oito dias, 2 meses e 6 meses após as irradiações foram realizados ensaios mecânicos de resistência a tração e elongação na ruptura, resistência da selagem e resistência à perfuração, todos com base nas suas respectivas normas ASTM [35]. Os ensaios de perfuração por insetos foram realizados em sala climatizada, onde amostras irradiadas nas doses de 0, 10, 20 e 60 kGy foram seladas contendo 40 g de granola, 40 g de macarrão e barra de cereais em número de nove por ensaio, e divididas igualmente em três caixas plásticas teladas por dose estudada. Em cada caixa foram adicionados 20 adultos de cada inseto em por 60 dias, quando as embalagens foram avaliadas para verificação de possíveis perfurações. As diferenças entre os resultados das amostras foram estatisticamente avaliados pelo método ANOVA (p<0,05). Os resultados mostraram que quanto à resistência a perfuração por L. serricorne, P. interpunctella e S. zeamais as estruturas poliméricas avaliadas apresentaram baixa resistência à perfuração por insetos antes e após o tratamento. BOPPmet/BOPP (50 &mu;m), PETmet/BOPP (32 &mu;m), PET/PP1 (72 &mu;m) e PET/PP2 (32 &mu;m) apresentaram perdas significativas nas estruturas nas propriedades mecânicas estudadas. O BOPP/PP (50 &mu;m) apresentou o melhor conjunto de respostas nas propriedades mecânicas ao tratamento por radiação com feixe de elétrons em doses de até 10 kGy. Dentre as propriedades mecânicas avaliadas a selagem foi a mais afetada pela radiação ionizante, tendo apresentado, em geral, perdas crescentes com a dose de radiação. / The plagues of stored products consist of a man problem, depreciating products and causing economical damages. Among these curses we have Lasioderma serricorne (F. 1792), Sitophilus zeamais (M. 1855) and Plodia interpunctella (H. 1813) known by infesting stored products as: grains, brans, flours, coffee, tobacco, dried fruits and spices. These curses perforate and penetrate the packages, ovipositing over the substratum. In this context the package plays a fundamental part, preventing the contact and curses proliferation in the packed product. So, to protect the packed product and to prolong its shelf life, the package should have good mechanical resistance to tension and perforation, good sealing, good barrier properties and should not transfer odors nor strange flavors to the packed product. The ionizing radiation can cause structural changes in polymer packages, these changes are caused by the scission processes and reticulation of the polymers chains. These are concurrent processes and the predominance of one over the other depends on the chemical structure of the polymer, the irradiation conditions and specific factors of the material that will absorb the energy. This work had the objective to evaluate the changes in mechanical properties of package structures used to store granola, cereal bar and pasta, as well as its resistance to perforation by L. serricorne, P. interpunctella and S. zeamais, when submitted to electrons sheaf radiation. In this methodology were used five structures of commercially utilized packages to store granola, cereal bar and pasta composed by (Polypropylene bi-oriented metallic/Polypropylene bi-oriented coextruded - BOPPmet/BOPP 50 &mu;m), (Polypropylene bi-oriented/Polypropylene - BOPP/PP 50 &mu;m), Poli (ethylene terephthalate) metallic/Polypropylene bi-oriented coextruded - PETmet/BOPP 32 &mu;m), Poli (ethylene terephthalate) /Polypropylene - PET/PP1 72 &mu;m), Poli (ethylene terephthalate)/Polypropylene - PET/PP2 32 &mu;m). The structures of packaging were submitted to radiation doses between 0, 10, 20 and 60 kGy, in one electron accelerator of 1,5 M and V, 25 mA and 37,5 kW, dose tax of 11,22 kGy / s, room temperature and air presence . Eight days, Two and Six months after irradiations, mechanical resistance experiment were accomplished to tension and elongating in rupture, sealing resistance and perforation resistance, all based in respective ASTM norms. The perforation experiment by insects were realized in an acclimatized room, where irradiated samples in doses of 0, 10, 20 and 60 kGy were sealed containing 40 g of granola, 40 g of pasta and cereal bar in number of nine by experiment, and equally divided in three plastic screened boxes by studied dose. In each box 20 adults of each insect were added in for 60 days, when the packages were evaluated to verify possible perforations. The differences between the sample results were statistically evaluated by ANOVA (p<0.05). The results showed that concerning the perforation resistance by L. serricorne, P. interpunctella and S. zeamais the polymeric structures evaluated showed low resistance by insects perforation before and after the treatment. BOPPmet/BOPP (50 &mu;m), PETmet/BOPP (32 &mu;m), PET/PP1 (72 &mu;m) and PET/PP2 (32 &mu;m) structures showed significant losses in mechanical properties studied. The BOPP/PP (50 &mu;m) showed the best set of answers in mechanical properties to the radiation treatment with electrons sheaf up to 10 kGy doses. Among the mechanical properties evaluated, sealing was the most affected by ionizing radiation, has shown, in general, increasing losses with radiation dose.
10

Untersuchungen zur Wirksamkeit insektenpathogener Pilze gegen die vorratsschädlichen Motten Ephestia Kuehniella und Plodia interpunctella (Lepidptera: Pyralidae)

Bischoff, Reinhard 05 June 1998 (has links)
In der vorliegenden Arbeit wurden anhand von Labor- und praxisnahen Flugversuchen die Möglichkeiten der biologischen Bekämpfung der Dörrobstmotte, Plodia interpunctella HÜBNER, und der Mehlmotte, Ephestia kuehniella (ZELLER), mit entomopathogenen Pilzen der Ordnung Hyphomycetales untersucht. Getestet wurden Pilzstämme von Metarhizium anisopliae, Beauveria bassiana, Paecilomyces farinosus und Paecilomyces fumosoroseus. Hauptgegenstand der experimentellen Arbeit war die Untersuchung verschiedener Einflußfaktoren auf die Wirksamkeit der Pilze unter Lagerbedingungen unter besonderer Berücksichtigung des Auftretens von Wechselwirkungen zwischen Erreger, Wirtsinsekt und Umwelt. Die Stammeigenschaften der getesteten Pilze wurden neben den herrschenden Umweltbedingungen als ein Hauptfaktor identifiziert, der die Wirksamkeit des Einsatzes entomopathogener Pilze gegen vorratsschädliche Motten entscheidend beeinflußt. Darüber hinaus sind der Ernährungszustand der Pilze, die Anfälligkeit der Wirtsinsekten sowie die Inokulumdichte verantwortlich für das Zustandekommen bedeutsamer Bekämpfungseffekte. Für eine praktische Nutzung wurden als mögliche Anwendungstechnologien die Kontamination von Verpackungen, die Behandlung von Fraß- bzw. Brutsubstrat unter Ausnutzung deren Lockwirkung sowie die Verwendung pheromonbeköderter Kontaminationsherde untersucht. Herausgestellt werden konnte, daß für nachhaltige kurative Bekämpfungserfolge die Dichte von P. interpunctella im Lager gering sein muß. Die Verwendung von pheromonbeköderten Kontaminatinsherden führte bei über 50% der Weibchen und etwa 80% der Männchen von P. interpunctella zur Inokulation und kann somit die Effizienz entomopathogener Pilze im Vorratsschutz erhöhen. / Strains of the entomopathogenic fungi Metarhizium anisopliae, Beauveria bassiana, Paecilomyces farinosus and Paecilomyces fumosoroseus were tested against the stored product infesting moths Plodia interpunctella HÜBNER, and Ephestia kuehniella (ZELLER). The potential of the strains was assessed by conducting experiments investigating the different factors influencing their effectiveness under stored conditions. The quality of virulence and the environmental conditions are the mean factors for a successful use of entomopathogenic fungi. Furthermore, the nutritional state of the fungi, the susceptibility of the moths and the density of inoculum influence the effect of a fungi treatment. The contamination of packing, the treatment of food and the use of contaminated TDA pheromone places was assessed for a practical method. The control of P. interpunctella is successful with slow population density of moths. The inoculation of Plodia interpunctella males and females showed that the combined action of pheromone and fungi spores could serve as potential method in the biological control of stored product infesting moths.

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