樹是一個沒有迴路的連接圖。而4-caterpillar是一種樹，它擁有單一路徑連接到數個長度為3的路徑的端點。一個有n個邊的無向圖G的優美標法是一個從G的點到{0,1,2,...,n}的一對一函數，使得每一個邊的標號都不一樣，其中，邊的標號是兩個相鄰的點的編號差的絕對值。在這篇論文當中，我們最主要的目的是使用一個演算法來完成4-caterpillars的優美標法。 / A tree is connected acyclic graph. A 4-caterpillar is a tree with a single path only incident to the end-vertices of paths of length 3. A graceful labelling of an undirected graph G with n edges is a one-to-one function from the set of vertices of G to the set {0,1,2,...,n} such that the induced edge labels are all distinct, where the edge label is the difference between two endvertex labels. In this thesis, our main purpose is to use an algorithm to yield graceful labellings of 4-caterpillars.

Este trabalho teve como principal objetivo, identificar os inimigos naturais de Lonomia obliqua Walker, 1855, lagarta da síndrome hemorrágica em humanos. Através de exemplares de L. obliqua coletados no campo e criados em laboratório, foi possível a obtenção de insetos das ordens Diptera, Hymenoptera e Hemiptera além de Vírus e Nematóide, todos atuando como inimigos naturais. A partir do conhecimento das localidades onde ocorreram os acidentes hemorrágicos, localizou-se e reconheceu-se o hábitat atual desses insetos. Comparando-se as características bióticas e abióticas atuais dessas localidades, geralmente rurais, com aquelas existentes no final do século XIX, época em que ocorreu a formação desses municípios, procurou-se discutir os principais fatores que possivelmente tiveram influência no aumento da população dessa espécie. / The main purpose of this study was to identify the natural enemies of Lonomia obliqua Walker, 1855, the caterpillar responsible for the hemorrhagic syndrome in human beings. From immatures of L. obliqua, collected in the field and reared in the laboratory, insects of the orders Diptera, Hymenoptera and Hemiptera, and also viruses and nematodes, were obtained. Based on the knowledge of the localities where hemorrhagic accidents were registered, the insect habitats were recognized. Comparing biotic and abiotic characteristics of these localities, generally rural, ones with those of the end of the XIX century, when the municipalities were created, an attempt was made to discuss the main factors might have influencing the increase of the species population.

As plantas reconhecem e produzem substâncias voláteis específicas para a atração de parasitóides após o ataque de um herbívoro, num processo conhecido como defesa indireta. Contudo, a capacidade dessas plantas em processar e liberar novos compostos voláteis sob o ataque de um herbívoro não hospedeiro permanece ainda inexplorado. Em vista disso, o presente trabalho buscou investigar o efeito dos voláteis emitidos por planta de milho sob o ataque de uma praga até então não hospedeira (traça-das-crucíferas, Plutella xylostella) comparado ao daqueles emitidos por planta de milho sob ataque de um hospedeiro tradicional (lagarta-do-cartucho-domilho, Spodoptera frugiperda), sobre esses insetos e seus respectivos parasitóides, Apanteles piceotrichosus e Campoletis flavicincta. Os bioensaios com os parasitóides foram conduzidos em fotofase, sendo oferecidos a estes, voláteis de plantas de milho sadias, voláteis liberados nos intervalos de 0-1, 5-6 e 24-25h após tratamento em fotofase por dano mecânico ou herbivoria simulada, e voláteis liberados no intervalo de 5-6h após esses mesmos tratamentos em escotofase. Já os ensaios com as mariposas foram conduzidos em escotofase, sendo oferecidos a estas, voláteis de plantas de milho sadias, voláteis liberados nos intervalos de 5-6h após tratamento em fotofase por dano mecânico ou herbivoria simulada, e voláteis liberados no intervalo de 0-1 e 24- 25h após esses mesmos tratamentos em escotofase. Adicionalmente, foram testados, para P. xylostella, voláteis de plantas de couve-manteiga sadia, e para A. piceotrichosus, voláteis de couve-manteiga sadia, couve-manteiga danificada mecanicamente e couve-manteiga atacada por lagartas de P. xylostella. As fêmeas de C. flavicincta apresentaram atratividade para voláteis emitidos pelas plantas de milho no intervalo de 5 a 6 horas após tratamento com regurgito de S. frugiperda em escotofase. Curiosamente, não apresentou atratividade pelos voláteis liberados nesse mesmo intervalo de tempo após indução com regurgito em fotofase. As fêmeas acasaladas de S. frugiperda foram atraídas por voláteis de plantas de milho sadia e voláteis liberados nos intervalos de 5-6 e 24-25h após dano mecânico ou tratamento da planta com regurgito deste herbívoro. Porém, preferiu voláteis de plantas sadias aqueles de plantas tratadas com regurgito em fotofase. Esses resultados demonstraram que esses insetos são capazes de discriminar entre misturas de voláteis presentes em seu habitat natural, onde ocorre a relação tritrófica milho (planta hospedeira) S. frugiperda (herbívoro) C. flavicincta (parasitóide). Da mesma forma, na relação couve-manteiga (planta hospedeira) P. xylostella (herbívoro) A. piceotrichosus (parasitóide), as fêmeas de P. xylostella foram atraídas pelos voláteis de couve-manteiga sadia, assim como as fêmeas de A. piceotrichosus foram atraídas pelos voláteis de couve-manteiga atacadas por lagartas deste herbívoro. No caso da simulação de uma nova relação, milho (planta não-hospedeira) P. xylostella (herbívoro) C. flavicincta (parasitóide), tanto fêmeas de A. piceotrichosus, quanto de P. xylostella, não foram capazes de responder aos voláteis de plantas de milho sadias, danificadas mecanicamente e danificadas mecanicamente + regurgito de P. xylostella. A determinação desses mecanismos poderá ser útil para maior compreensão do contexto evolutivo entre plantas e insetos e obtenção de novos avanços no manejo e controle biológico de pragas. / Plants recognize and produce specific volatile substances that attract parasitoids after the herbivore attack, characterizing a process known as indirect defense. However, the ability of these plants in processing and releasing novel volatile compounds elicited by a non-host herbivore attack has been poorly explored. Regarding this, the current study aimed to investigate the effect of volatiles emitted by maize plants under the attack of a pest which is not a host so far, diamondback moth, Plutella xylostella compared to those emitted by a common host, fall armyworm, Spodoptera frugiperda on the behavior response of these insects and their respective parasitoids Apanteles piceotrichosus e Campoletis flavicincta. The bioassays with the parasitoids were conducted during photophase and they were exposed to volatiles from undamaged maize, volatiles released at the time intervals 0-1, 5-6 and 24-25h after the treatment of mechanical damage or simulated herbivory during photophase, and volatiles released at the time interval 5-6h after these same treatments in scotophase. The bioassays with the moths were carried out in scotophase and they were exposed to volatiles from undamaged maize, volatiles released at the time interval 5-6h after the treatment of mechanical damage or simulated herbivory during photophase, and volatiles released at time intervals 0-1 and 24-25h after these same treatments in scotophase. Additionally, for P. xylostella volatiles from undamaged kale were tested while for A. piceotrichosus it was tested volatiles from undamaged kale, mechanically damaged and P. xylostella caterpillar damaged kale. C. flavicincta females were attracted to volatiles emitted by the maize plants at the interval 5-6h after the treatment with the S. frugiperda regurgitate in scotophase. Curiously, they were not attracted to volatiles released at the same time interval after the induction elicited by the regurgitate in the photophase. S. frugiperda mated females were attracted by volatiles from undamaged plants and volatiles released at time intervals 5-6 and 24- 25h after the mechanical damage or treated with the regurgitate of this herbivore. Nevertheless, they preferred the volatiles from undamaged maize to the plants treated with the regurgitate during photophase. These results demonstrated that these insects are able to distinguish among the volatile blends present in their natural habitat where it occurs the tritrophic relationship maize (host plant) S. frugiperda (herbivore) C. flavicincta (parasitoid). In the same way, in the relationship kale (host plant)- P. xylostella (herbivore) A. piceotrichosus (parasitoid), P. xylostella females were attracted by the volatiles of undamaged kale as well as the A. piceotrichosus females were attracted to volatiles emited by caterpillar-damaged kale. In the case of simulating a new relationship, maize (non-host plant) P. xylostella (herbivore) C. flavicincta (parasitoid), A. piceotrichosus females and P. xylostella were not able to respond to undamaged maize, mechanically damaged and mechanically damaged+ P. xylostella regurgitate. The determination of these mechanisms can be useful for a better understanding of the evolution context between plants and insects and for obtaining new advances in the management and biological pest control.

Invasive insects are considered one of the most serious threats affecting forests today; however, surprisingly little research has addressed the impacts of invasive species establishment on native forest insect communities. Such information is lacking for even the most thoroughly studied invasive forest insect, the gypsy moth. Using gypsy moth as a case study, my thesis addresses the questions: What are the ecological impacts of an exotic forest insect upon its establishment in a new community of native species? Does the community shift after the invasive establishes, and if so, what are the drivers in this realignment? I used multivariate analysis to assess native caterpillar communities collected in forest stands with and without a history of gypsy moth outbreak. I found that gypsy moth outbreak history had no significant effects on native caterpillar communities; however, current gypsy moth abundance was related to shifts in the structure of late season caterpillar assemblages. These results suggest that gypsy moth may affect native caterpillar communities through short-term mechanisms but not through long-term ecological changes. I used quantitative food webs to investigate the effects of gypsy moth on native host-parasitoid webs from the same caterpillar communities, and found that food web structure was resilient to both gypsy moth outbreak history and current abundance. The gypsy moth shared few parasitoids with native species in my study sites, none of numerical significance, thus minimizing the opportunity for enemy-mediated indirect interactions. Finally, I conducted a greenhouse experiment and found that early spring feeding by forest tent caterpillar can indirectly influence gypsy moth susceptibility to its virus, demonstrating that the complex interactions that can occur between native and exotic species do not always benefit the invader. Overall, I argue that the establishment of the gypsy moth into North American forests will not cause major changes in native caterpillar communities.

Invasive insects are considered one of the most serious threats affecting forests today; however, surprisingly little research has addressed the impacts of invasive species establishment on native forest insect communities. Such information is lacking for even the most thoroughly studied invasive forest insect, the gypsy moth. Using gypsy moth as a case study, my thesis addresses the questions: What are the ecological impacts of an exotic forest insect upon its establishment in a new community of native species? Does the community shift after the invasive establishes, and if so, what are the drivers in this realignment? I used multivariate analysis to assess native caterpillar communities collected in forest stands with and without a history of gypsy moth outbreak. I found that gypsy moth outbreak history had no significant effects on native caterpillar communities; however, current gypsy moth abundance was related to shifts in the structure of late season caterpillar assemblages. These results suggest that gypsy moth may affect native caterpillar communities through short-term mechanisms but not through long-term ecological changes. I used quantitative food webs to investigate the effects of gypsy moth on native host-parasitoid webs from the same caterpillar communities, and found that food web structure was resilient to both gypsy moth outbreak history and current abundance. The gypsy moth shared few parasitoids with native species in my study sites, none of numerical significance, thus minimizing the opportunity for enemy-mediated indirect interactions. Finally, I conducted a greenhouse experiment and found that early spring feeding by forest tent caterpillar can indirectly influence gypsy moth susceptibility to its virus, demonstrating that the complex interactions that can occur between native and exotic species do not always benefit the invader. Overall, I argue that the establishment of the gypsy moth into North American forests will not cause major changes in native caterpillar communities.

No description available.

Thesis (Ph.D.) -- Mississippi State University. Department of Biochemistry and Molecular Biology. / Title from title screen. Includes bibliographical references.

Made available in DSpace on 2014-06-11T19:25:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-28Bitstream added on 2014-06-13T20:53:01Z : No. of bitstreams: 1 salvador_mc_me_jabo.pdf: 7027477 bytes, checksum: 394b5cb96a70d0501615adb0cf5b09f4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Resultados de efeitos de compostos fenólicos incorporados em dietas artificiais têm sido contestados, principalmente pela presença de proteínas com alto valor nutritivo, como a caseína, que podem influenciar a atividade dos aleloquímicos. Genótipos de soja resistentes a insetos têm apresentado flavonóides em sua composição, tornando necessária a informação sobre a interação deste fenólico com dieta. Adicionalmente, avaliaram-se os efeitos de dietas artificiais, contendo diferentes concentrações de rutina (R) e genistina (G), e de genótipos de soja nos aspectos biológicos, assim como o modo de ação desses alimentos no intestino médio (IM) de A. gemmatalis. O efeito de rutina foi potencializado apenas quando as lagartas se alimentaram com dietas com 7g de caseína, ou seja, a metade da necessária para o desenvolvimento adequado do inseto. Dietas com as maiores concentrações de rutina (R2) e a mistura R1+G1 e folhas de PI 227687 e ‘IAC-100’ foram responsáveis pela maior mortalidade, redução dos pesos iniciais e de pupa, menor ganho de peso e crescimento. Estes tratamentos, principalmente R1+G1 e ‘IAC-100’ ainda provocaram maiores alterações morfológicas no IM da lagarta. Dietas e genótipos contendo apenas genistina não apresentaram acentuado efeito antinutricional no inseto e nem alterações morfológicas importantes. Assim sendo, estes resultados permitem concluir que a interação das substâncias R e G observadas em folhas de soja, como a ‘IAC-100’ e PI 227687, atua na proteção da planta ao ataque de A. gemmatalis, possivelmente por alterar as células colunares do IM. / Results regarding the effects of phenolics incorporated in artificial diets have been contested, mainly by the presence of high nutritive proteins as casein. This protein can cause deep influence in the alelochemical activity on herbivores. Resistant soybean genotypes have presented flavonoids, as rutin (R), in their chemical profile, turning necessary the information related to the interaction of such phenolic compound with the artificial diet. Additionally, effects of diets, with different concentration of R and genistin (G), and of soybean leaves on biological aspects, as well as, on the mode of action of them in A. gemmatalis midgut were evaluated. Rutin effect was only potentialized when larvae fed on diet with 7g of casein, i.e., half of amount necessary for an adequate insect development. Insects fed on artificial diet containing R2 (the highest rutin concentration) or R1+G1 (mixture of R and G), on PI 227687 and ‘IAC-100’ caused higher mortality, reduction in weighs of larvae (end of second instar) and pupae, also gained less weigh and presented lower growth compared to other diets. These treatments, mainly R1+G1 and ‘IAC-100’ also presented more morphologic alterations in the insect midgut. Diets and genotypes containing only genistin did not show accentuated antinutritional effect and presented less intense morphologic alterations in the insect midgut. Thus, these results allow suggesting that R and G, observed in leaves of soybean, as ‘IAC-100’ and PI 227687, interacts in the protection of the plant to A. gemmatalis attack, possibly by causing alterations in columnar cells of midgut.

Resumo: Resultados de efeitos de compostos fenólicos incorporados em dietas artificiais têm sido contestados, principalmente pela presença de proteínas com alto valor nutritivo, como a caseína, que podem influenciar a atividade dos aleloquímicos. Genótipos de soja resistentes a insetos têm apresentado flavonóides em sua composição, tornando necessária a informação sobre a interação deste fenólico com dieta. Adicionalmente, avaliaram-se os efeitos de dietas artificiais, contendo diferentes concentrações de rutina (R) e genistina (G), e de genótipos de soja nos aspectos biológicos, assim como o modo de ação desses alimentos no intestino médio (IM) de A. gemmatalis. O efeito de rutina foi potencializado apenas quando as lagartas se alimentaram com dietas com 7g de caseína, ou seja, a metade da necessária para o desenvolvimento adequado do inseto. Dietas com as maiores concentrações de rutina (R2) e a mistura R1+G1 e folhas de PI 227687 e 'IAC-100' foram responsáveis pela maior mortalidade, redução dos pesos iniciais e de pupa, menor ganho de peso e crescimento. Estes tratamentos, principalmente R1+G1 e 'IAC-100' ainda provocaram maiores alterações morfológicas no IM da lagarta. Dietas e genótipos contendo apenas genistina não apresentaram acentuado efeito antinutricional no inseto e nem alterações morfológicas importantes. Assim sendo, estes resultados permitem concluir que a interação das substâncias R e G observadas em folhas de soja, como a 'IAC-100' e PI 227687, atua na proteção da planta ao ataque de A. gemmatalis, possivelmente por alterar as células colunares do IM. / Abstract: Results regarding the effects of phenolics incorporated in artificial diets have been contested, mainly by the presence of high nutritive proteins as casein. This protein can cause deep influence in the alelochemical activity on herbivores. Resistant soybean genotypes have presented flavonoids, as rutin (R), in their chemical profile, turning necessary the information related to the interaction of such phenolic compound with the artificial diet. Additionally, effects of diets, with different concentration of R and genistin (G), and of soybean leaves on biological aspects, as well as, on the mode of action of them in A. gemmatalis midgut were evaluated. Rutin effect was only potentialized when larvae fed on diet with 7g of casein, i.e., half of amount necessary for an adequate insect development. Insects fed on artificial diet containing R2 (the highest rutin concentration) or R1+G1 (mixture of R and G), on PI 227687 and 'IAC-100' caused higher mortality, reduction in weighs of larvae (end of second instar) and pupae, also gained less weigh and presented lower growth compared to other diets. These treatments, mainly R1+G1 and 'IAC-100' also presented more morphologic alterations in the insect midgut. Diets and genotypes containing only genistin did not show accentuated antinutritional effect and presented less intense morphologic alterations in the insect midgut. Thus, these results allow suggesting that R and G, observed in leaves of soybean, as 'IAC-100' and PI 227687, interacts in the protection of the plant to A. gemmatalis attack, possibly by causing alterations in columnar cells of midgut. / Orientador: Arlindo Leal Boiça Junior / Coorientadora: Clara Beatriz Hoffmann-Campo / Banca: André Luiz Lourenção / Banca: Antonio Carlos Busoli / Mestre

Este trabalho teve como principal objetivo, identificar os inimigos naturais de Lonomia obliqua Walker, 1855, lagarta da síndrome hemorrágica em humanos. Através de exemplares de L. obliqua coletados no campo e criados em laboratório, foi possível a obtenção de insetos das ordens Diptera, Hymenoptera e Hemiptera além de Vírus e Nematóide, todos atuando como inimigos naturais. A partir do conhecimento das localidades onde ocorreram os acidentes hemorrágicos, localizou-se e reconheceu-se o hábitat atual desses insetos. Comparando-se as características bióticas e abióticas atuais dessas localidades, geralmente rurais, com aquelas existentes no final do século XIX, época em que ocorreu a formação desses municípios, procurou-se discutir os principais fatores que possivelmente tiveram influência no aumento da população dessa espécie. / The main purpose of this study was to identify the natural enemies of Lonomia obliqua Walker, 1855, the caterpillar responsible for the hemorrhagic syndrome in human beings. From immatures of L. obliqua, collected in the field and reared in the laboratory, insects of the orders Diptera, Hymenoptera and Hemiptera, and also viruses and nematodes, were obtained. Based on the knowledge of the localities where hemorrhagic accidents were registered, the insect habitats were recognized. Comparing biotic and abiotic characteristics of these localities, generally rural, ones with those of the end of the XIX century, when the municipalities were created, an attempt was made to discuss the main factors might have influencing the increase of the species population.