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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

Controle biológico do pulgão de trigo Sitobion avenae (Fabricius 1775) pelo parasitóide Aphidius colemani Viereck, 1912 em Medianeira, PR, Brasil / Biological control of the wheat louse Sitobion avenae (Fabricius 1775) by the parasite Aphidius colemani (VIEREK 1912) in the city of Medianeira, Paraná, Brazil

Zanini, Agostinho 20 December 2004 (has links)
Made available in DSpace on 2017-07-10T17:37:35Z (GMT). No. of bitstreams: 1 Agostinho_Zanini.pdf: 491209 bytes, checksum: aa69bdfc4d8e8d46497bf943712eca7c (MD5) Previous issue date: 2004-12-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Historically, aphids were the main phytosanitary problem in the production of winter cereals in de 70 s in southern Brazil. Attacking intensively during wheat s emergence to the affiliation, it s usually fatal to the plant. However, these bugs possess important population suppression that, although considered the most efficient and specific, had a frail role in aphid natural biological control in wheat production in Brazil where chemical control became necessary to prevent production loss. Thereby, in 1978 14 species of exotic parasites were introduced in Brazil aiming plaque control, and in 1984 the West of Parana s Biological Control Program was introduced when 4 species were released. Along the years, it provided an aphid population reduction and consequently the reduction on chemical applications. The reason of this study is because no bibliographic studies referring to the settlement of the parasite in the west of Paraná s region was found. A weekly sampling, in twenty-five 25 m2 parcels, of 100 wheat plants was taking where the aphids and mummies were removed. A single aphid specie, Sitobion avenae (Fabricius), was found, the primary parasite Aphidius colemani (Vierek 1912), and hyper-parasites. It was also detected the presence of predators. Population summit of S. avenae occurred at the beginning of blossoming and mummies showed up a week following the aphids. Parasite emergence was observed in 34% of the collected mummies, 29.4% of hyper-parasites, and no emergence was found in 36.6% of the total. Aphid control was found to be excellent, because as their population increased so did the parasite A. colemani level, reaching its population peak in early August with 37.2%. Hyper-parasites reached population peak in mid-August, and predator number was lower than the number of parasites. Considering the number of parasites released, 14 different species altogether, and the fact that only one species in 2003 was found indicates that probably, in the west of Paraná s region, conditions were not favorable to the other 13 but to A. colemani / Historicamente os afídeos foram o principal problema fitossanitário no cultivo de cereais de inverno na década de 70, no Sul do Brasil. Em ataques intensos, nas fases de emergência ao perfilhamento do trigo, em geral, levam as plantas à morte. No entanto, estes insetos possuem importantes agentes de supressão populacional, dentre os quais os parasitóides, que embora considerados os mais específicos e eficientes, tinham fraco desempenho no controle biológico natural dos afídeos na cultura do trigo, no Brasil, havendo necessidade de controle químico para evitar as perdas. Assim, em 1978, foram introduzidas 14 espécies de parasitóides exóticos no Brasil, tendo como objetivo o controle da praga e, em 1984, implantou-se o Programa de Controle Biológico no Oeste do Estado do Paraná, liberando-se quatro espécies. Este proporcionou, ao longo dos anos, uma redução das populações de afídeos e, conseqüentemente, da aplicação de produtos químicos. No entanto, apesar do grande sucesso, não foram encontrados na bibliografia estudos referentes ao estabelecimento de parasitóides na região Oeste do Paraná, motivo pelo qual desenvolveu-se o presente estudo. Coletou-se semanalmente em 25 parcelas com 25m2, 100 plantas de trigo, retirando-se das mesmas os afídeos e múmias. Encontrou-se uma única espécie de afídeo Sitobion avenae (Fabricius), o parasitóide primário Aphidius colemani Vierek e hiperparasitóides, verificando-se também a presença de predadores. O pico populacional de S. avenae ocorreu no início da floração e as múmias apareceram uma semana após aos afídeos. Observou-se a emergência de parasitóides em 34% das múmias coletadas, 29,4% de hiperparasitóides e em 36,6% delas, nada emergiu. Considerou-se eficiente o controle dos afídeos (95%), pois à medida que sua população foi se elevando, concomitantemente, se elevaram os níveis de parasitismo de A. colemani, atingindo o pico populacional no início de agosto com 37,2%. Os hiperparasitóides atingiram pico populacional em meados de agosto, com 29,4% e o número de predadores foi menor que o de parasitóides. Considerando que a relação de parasitóides liberados no Brasil continha 14 espécies diferentes, o fato de apenas uma ter sido encontrada em 2003 indica que na região oeste do Paraná, provavelmente, as condições foram favoráveis apenas para A. colemani
2

Ekologie denních motýlů tradičně obhospodařovaných podhorských luk / Ecology of butterflies traditionally managed submontane meadows

ZIMMERMANN, Kamil January 2011 (has links)
The persistence of Marsh fritillary (Euphydryas aurinia) and its relationships with five other closly related and co-occuring Nymphalidae butterflies was studied in identical habitat networks. Basic demography and dispersal patterns, and their consequences for conservation strategies, were investigated across mutliple sites and seasons.
3

Análise comparativa das espécies de Anastrepha (Diptera, Tephritidae) em três agroecossistemas no estado de São Paulo / Comparative analysis of Anastrepha (Diptera, Tephritidae) species in three agroecosystems in the State of São Paulo, Brazil

Oliveira, Monique Bárbara Rosa de 26 March 2015 (has links)
As moscas-das-frutas estão entre as principais pragas da pomicultura em todo o mundo. Devido à sua importância econômica, os estudos sobre os aspectos ecológicos entre as comunidades moscas-das-frutas são cruciais. Assim, o objetivo deste trabalho foi comparar a dinâmica populacional das espécies de Anastrepha em três agroecossistemas diferentes, de três municípios do estado de São Paulo: área antropizada em Piracicaba, área natural em Monte Alegre do Sul e na área agrícola em Monte Alto. Os levantamentos moscas-das-frutas foram realizados utilizando armadilha do tipo McPhail com atrativo alimentar. As comparações das comunidades de moscas-das-frutas foram baseadas nos índices faunísticos. Um total de 49.583 espécimes foram coletados nos três agroecossistemas, pertencentes a 22 espécies. Anastrepha fraterculus e A. sororcula foram predominantes em todos os três agroecossistemas. Anastrepha bahiensis e A. grandis também foram predominantes na área natural, mas na área antropizada apenas A. pseudoparallela foi predominante. Todas essas espécies foram classificadas como super quanto à dominância, abundância, frequência e constância. Embora o índice de diversidade foi elevado na área antropizada, o maior índice de riqueza (Margalef) foi na área natural. Pelo índice de equitabilidade (Pielou), a distribuição das espécies foi mais uniforme na área agrícola. Para a diversidade beta, determinada pelo coeficiente de similaridade (Sørensen), áreas antropizada e natural tiveram 80% de similaridade, diferindo estatisticamente da semelhança com a área agrícola. No entanto, com base no coeficiente de Bray-Curtis, a área natural foi a mais dissimilar, diferindo das áreas antropizada e agrícola. Com base na distância euclidiana, A. fraterculus teve forte interação nos três agroecossistema. De acordo com os índices de diversidade nos três agroecossistemas, a área agrícola, onde foram usados tratamentos fitossanitários, diferiu significativamente das áreas antropizada e natural, tanto na diversidade alfa como beta. / Fruit flies are among the main pests of the pomiculture worldwide. Due to their economic importance, studies on the ecological aspects among fruit fly communities are crucial. Thus, the objective of this work was to compare the population dynamics of Anastrepha species in three different agroecosystems of three municipalities of the state of São Paulo, Brazil: anthropic area in Piracicaba, natural area in Monte Alegre do Sul and agricultural area in Monte Alto. Fruit fly surveys were carried out using McPhail-type trap with food attractants. Comparisons of the fruit fly communities were based on faunistic indices. A total of 49.583 specimens were collected in the three agroecosystems divided in 22 species. Anastrepha fraterculus and A. sororcula were predominant in all three agroecosystems. Anastrepha bahiensis and A. grandis were also predominant in the natural areas, but in the anthropic area only A. pseudoparallela was predominant. All these species were classified as super for the indices dominance, abundance, frequency and constancy. Although the diversity index was high in the anthropic area, the highest richness index (Margalef) was in the natural area. The species distribution was more evenly in the agricultural area by the equitability index (Pielou). For the diversity beta, determined by the similarity coefficient (Sorensen), anthropic and natural areas had 80% of similarity, differing statistically from the similarity with the agricultural area. However, based on the Bray-Curtis coefficient, the natural areas was the most dissimilar, differing from the anthropic and agricultural areas. Based on the Euclidean distance, A. fraterculus had strong interaction in the three agroecosystems. According to the diversity indices for the three agroecosystems, the agricultural area, where pesticides were used, differed significantly from the anthropic and natural areas in both alpha and beta diversity.
4

Dinâmica populacional e mecanismos de tolerância de espécies de plantas daninhas ao herbicida Glyphosate. / Population dynamic and tolerance mechanisms of weed species to the glyphosate herbicide.

Monquero, Patrícia Andréa 16 September 2003 (has links)
Aplicações repetitivas do herbicida glyphosate podem resultar em mudanças nas populações de plantas daninhas, devido a uma pressão seleção sobre espécies de plantas daninhas tolerantes ao herbicida. No entanto, os mecanismos de tolerância dessas espécies não estão completamente compreendidos, e a elucidação desses mecanismos é fundamental nas recomendações de estratégias para o manejo de plantas daninhas tolerantes ao glyphosate. Sendo assim, os objetivos desta pesquisa foram: (i) avaliar a dinâmica do banco de sementes das espécies de plantas daninhas Commelina benghalensis L., Ipomoea grandifolia (Dammer) O’Don e Richardia brasiliensis Gomez (tolerantes), Amaranthus hybridus L. e Galinsoga parviflora Cav. (suscetíveis), em áreas tratadas intensivamente com doses de glyphosate por dois anos consecutivos, (ii) caracterizar os mecanismos de tolerância C. benghalensis e I. grandifolia ao herbicida glyphosate e (iii) estudar a eficácia de controle sobre as plantas daninhas tolerantes por herbicidas alternativos isolados e em mistura com glyphosate. Nos estudos de dinâmica do banco de sementes foram coletadas periodicamente amostras de solos de uma área com aplicação repetitiva do glyphosate para analise quantitativa e qualitativa através de extração das sementes e de germinação de sementes em casa-de-vegetação. Na caracterização dos mecanismos de tolerância, experimentos foram instalados para quantificar a absorção e a translocação de 14 C glyphosate pelas plantas C. benghalensis, I. grandifolia, A. hybridus e Glycine max resistente (R) e suscetível (S) ao glyphosate, às 2, 4, 8, 12, 24, 48 e 72 horas após tratamento (HAT); analisando-se, ainda, o metabolismo do glyphosate pelas plantas daninhas a 72 HAT. Cromatografia de camada delgada foi utilizada para determinar à composição química das ceras epicuticulares e microscopia eletrônica de varredura para a caracterização da superfície foliar das plantas daninhas. Experimento em casa de vegetação com os herbicidas alternativos carfentrazone, flumioxazin, sulfentrazone, chlorimuron-ethyl e bentazon foi conduzido para testar as interações aditivas, sinergísticas ou antagônicas com glyphosate no controle de plantas daninhas tolerantes. Os resultados foram: Ao final de dois anos de aplicação repetitiva de glyphosate houve um acréscimo do banco de sementes das plantas daninhas tolerantes, e um decréscimo no banco de sementes das plantas daninhas sensíveis ao glyphosate. A taxa de absorção e translocação do 14 C glyphosate em A. hybridus e Glycine max R e S foi maior que das demais plantas estudadas; I. grandifolia apresentou excelente taxa de absorção, entretanto, a translocação desta espécie foi reduzida. Em C. benghalensis a taxa de absorção foliar do glyphosate foi baixa, porém, não houve impedimento a translocação. Em C. benghalensis foi encontrado, além de glyphosate, o metabólito ácido aminometilfosfônico (AMPA). As ceras da cutícula foliar de A. hybridus e I. grandifolia apresentaram características predominantemente hidrofílicas, e a superfície foliar não apresentou tricomas, sendo observado uma grande quantidade de estômatos. As ceras epicuticulares destas duas espécies de plantas daninhas apresentaram forma cristalina apenas em A. hybridus. Em C. benghalensis as ceras são relativamente mais hidrofóbicas, o que pode ter influenciado na menor penetração de glyphosate; sendo que, a superfície foliar apresenta tricomas e um número menor de estômatos, e estes estão recobertos por cera epicuticular. / Intensive applications of the herbicide glyphosate for weed control may result in the weed population changes, through selection pressure of the glyphosate tolerant weed species. However, the glyphosate tolerance mechanisms of these species are not completely understood, and the elucidation of these mechanisms is fundamental to the recommendations of alternative herbicides to glyphosate tolerant weed management. Therefore, the objectives of this research were: (i) to evaluate the weed seed bank dynamic of the species Commelina benghalensis L., Ipomoea grandifolia (Dammer) O’Don and Richardia brasiliensis Gomez (tolerants to glyphosate), Amaranthus hybridus L. and Galinsoga parviflora Cav. (susceptibles to glyphosate), in areas that had been intensively treated with glyphosate rates for two consecutive years; (ii) to characterize the glyphosate tolerance mechanisms of C. benghalensis and I. grandifolia, and (iii) to study the efficacy of alternative herbicides in mixture with glyphosate in the control of tolerant weeds. The weed seed bank dynamic was evaluated through soil samples collected periodically, and analysed quantitative and qualitativelly by greenhouse germination test and seeds counting. Experiments were conducted to caracterize the absorption and translocation of 14 C glyphosate by C. benghalensis, I. grandifolia, A. hybridus and Glycine max resistant (R) and susceptible (S) to glyphosate, at 2, 4, 8, 12, 24, 48 and 72 hours after treatment (HAT); and analysing the glyphosate metabolism by the weeds at 72 HAT. Thin layer chromatography was used to determine the chemical composition of the epicuticular layers and eletronic microscopy to caracterize the foliar surface of the weeds. Greenhouse experiment with the alternative herbicides carfentrazone, flumioxazin, sulfentrazone, chlorimuron-ethyl and bentazon were conducted to test aditive, sinergistic or antagonic interactions with glyphosate on the control of the tolerant weeds. After two years of repetitive glyphosate application there was an increase in the weed seed bank of the tolerant species, and a decrease of the weed seed bank of the susceptible species to glyphosate. The rate of absorption and translocation of the 14 C glyphosate by A. hybridus and Glycine max R and S was higher than the other studied plants, likewise I. grandifolia presented an excelent rate of absorption, even tough, the translocation of this species was reduced. In C. benghalensis the glyphosate rate of foliar absorption was low, however, there was a free translocation of the herbicide. No glyphosate metabolites were observed in I. grandifolia and A. hybridus, however, in C. benghalensis it was found, besides glyphosate, the aminophosphonic acid (AMPA) metabolite. The cuticle waxes of A. hybridus and I. grandifolia presented predominantly hydrophilic characteristics, and the foliar surface did not present tricomes, being observed a great amount of stomata. The epicuticular waxes of this two weed species presented crystal form only in A. hybridus. In C. benghalensis the waxes were relatively more hidrofobics, which could be influenced on lower penetration of glyphosate; the foliar surface present tricomes and fewer stomata, and these are recovered by epicuticular wax.
5

Estudo comparativo de duas populações de capivaras (Hydrochaeris hydrochaeris) no município de Pirassununga, SP / Comparative study of two capybara (Hydrochaeris hydrochaeris) populations in the district of Pirassununga, SP

Vargas, Flavia Carolina 14 September 2005 (has links)
O presente trabalho teve como objetivo conhecer os fatores que propiciam as grandes densidades ecológicas de capivaras, através da comparação das dinâmicas populacionais de dois agrupamentos, em diferentes localidades do município de Pirassununga, SP (Campus Administrativo da Universidade de São Paulo – USP/Pirassununga e o Centro de Pesquisa e Gestão de Recursos Pesqueiros e Continentais – CEPTA/Ibama), para que futuramente seja possível propor uma metodologia de manejo que promova o controle populacional dessa espécie no Estado de São Paulo. Para tanto, foi realizado o monitoramento populacional de ambos agrupamentos durante 15 meses, através da contagem direta dos animais, constituindo na principal fonte de informação para determinar as dinâmicas populacionais. Adicionalmente realizaram-se as capturas dos indivíduos de ambas populações pelo uso de bretes fixos, para que fossem feitas as pesagens, sexagens e marcações eletrônicas pelo uso de microchips e assim, conhecer a distribuição etária, bem como a proporção entre sexos. O uso de ceva no interior dos bretes, para a atração dos animais, possibilitou a realização das contagens diretas e das capturas e recapturas. Para a análise das dinâmicas populacionais foram realizadas as comparações descritivas e estatísticas das densidades ecológicas das populações e das respectivas classes etárias, além do cálculo da taxa de crescimento das mesmas. A alimentação em ceva apresentou-se influenciada pela hierarquia de dominância social, o que fez com que apenas as parcelas dominantes fossem capturadas. Percebeu-se, através das capturas, que o número de fêmeas apreendidas foi superior ao de machos nas parcelas dominantes das duas populações. Por meio das observações foram detectados indivíduos satélites e subagrupamentos, cuja ocorrência pode caracterizar um sistema biológico de metapopulação. A comparação descritiva e estatística das densidades ecológicas das populações, bem como a comparação das taxas de crescimento revelaram superioridade populacional do agrupamento do CEPTA/Ibama em relação ao Campus da USP/Pirassununga, provavelmente pelo maior número de picos de acasalamentos observados, os quais possivelmente são influenciados pelo tipo de habitat antropizado e abundante em recursos hídricos presente no CEPTA/Ibama. / The present research aimed the knowledge of the factors that allow the high ecological densities of capybaras through the population dynamics comparison of two capybara groups in the district of Pirassununga, SP (Campus Administrativo da Universidade de São Paulo – USP/Pirassununga and Centro de Pesquisa e Gestão de Recursos Pesqueiros e Continentais – CEPTA/Ibama), intending to propose forward a management methodology for capybara population control in the State of São Paulo. The populations monitoring was carried out through direct count of animals during 15 months, which played the main role to determine the population dynamics. Fixed traps were used to allow the weightings, sex definitions and identification through microchips, and also to know the age distribution and sex ratios. It was used bait inside the traps to attract animals and thus make direct counting and capture possible. To analyze population dynamics it was used the population ecological densities comparisons (statistically and descriptively) and also their rates of increase. It was detected social dominance hierarchy inside the traps, thus only the dominant part of population could be caught. Females represented the majority among captured animals. Satellites individuals and new groups were seen during observations and their existence might characterize a biological system of metapopulation. The descriptive and statistic comparisons of population ecological densities, as well as their rates of increase showed population superiority of CEPTA/Ibama’s group probably for its bigger reproduction effort detected, which possibly receives influence of anthropogenic and water abundant habitats of CEPTA/Ibama.
6

Dinâmica populacional e mecanismos de tolerância de espécies de plantas daninhas ao herbicida Glyphosate. / Population dynamic and tolerance mechanisms of weed species to the glyphosate herbicide.

Patrícia Andréa Monquero 16 September 2003 (has links)
Aplicações repetitivas do herbicida glyphosate podem resultar em mudanças nas populações de plantas daninhas, devido a uma pressão seleção sobre espécies de plantas daninhas tolerantes ao herbicida. No entanto, os mecanismos de tolerância dessas espécies não estão completamente compreendidos, e a elucidação desses mecanismos é fundamental nas recomendações de estratégias para o manejo de plantas daninhas tolerantes ao glyphosate. Sendo assim, os objetivos desta pesquisa foram: (i) avaliar a dinâmica do banco de sementes das espécies de plantas daninhas Commelina benghalensis L., Ipomoea grandifolia (Dammer) O’Don e Richardia brasiliensis Gomez (tolerantes), Amaranthus hybridus L. e Galinsoga parviflora Cav. (suscetíveis), em áreas tratadas intensivamente com doses de glyphosate por dois anos consecutivos, (ii) caracterizar os mecanismos de tolerância C. benghalensis e I. grandifolia ao herbicida glyphosate e (iii) estudar a eficácia de controle sobre as plantas daninhas tolerantes por herbicidas alternativos isolados e em mistura com glyphosate. Nos estudos de dinâmica do banco de sementes foram coletadas periodicamente amostras de solos de uma área com aplicação repetitiva do glyphosate para analise quantitativa e qualitativa através de extração das sementes e de germinação de sementes em casa-de-vegetação. Na caracterização dos mecanismos de tolerância, experimentos foram instalados para quantificar a absorção e a translocação de 14 C glyphosate pelas plantas C. benghalensis, I. grandifolia, A. hybridus e Glycine max resistente (R) e suscetível (S) ao glyphosate, às 2, 4, 8, 12, 24, 48 e 72 horas após tratamento (HAT); analisando-se, ainda, o metabolismo do glyphosate pelas plantas daninhas a 72 HAT. Cromatografia de camada delgada foi utilizada para determinar à composição química das ceras epicuticulares e microscopia eletrônica de varredura para a caracterização da superfície foliar das plantas daninhas. Experimento em casa de vegetação com os herbicidas alternativos carfentrazone, flumioxazin, sulfentrazone, chlorimuron-ethyl e bentazon foi conduzido para testar as interações aditivas, sinergísticas ou antagônicas com glyphosate no controle de plantas daninhas tolerantes. Os resultados foram: Ao final de dois anos de aplicação repetitiva de glyphosate houve um acréscimo do banco de sementes das plantas daninhas tolerantes, e um decréscimo no banco de sementes das plantas daninhas sensíveis ao glyphosate. A taxa de absorção e translocação do 14 C glyphosate em A. hybridus e Glycine max R e S foi maior que das demais plantas estudadas; I. grandifolia apresentou excelente taxa de absorção, entretanto, a translocação desta espécie foi reduzida. Em C. benghalensis a taxa de absorção foliar do glyphosate foi baixa, porém, não houve impedimento a translocação. Em C. benghalensis foi encontrado, além de glyphosate, o metabólito ácido aminometilfosfônico (AMPA). As ceras da cutícula foliar de A. hybridus e I. grandifolia apresentaram características predominantemente hidrofílicas, e a superfície foliar não apresentou tricomas, sendo observado uma grande quantidade de estômatos. As ceras epicuticulares destas duas espécies de plantas daninhas apresentaram forma cristalina apenas em A. hybridus. Em C. benghalensis as ceras são relativamente mais hidrofóbicas, o que pode ter influenciado na menor penetração de glyphosate; sendo que, a superfície foliar apresenta tricomas e um número menor de estômatos, e estes estão recobertos por cera epicuticular. / Intensive applications of the herbicide glyphosate for weed control may result in the weed population changes, through selection pressure of the glyphosate tolerant weed species. However, the glyphosate tolerance mechanisms of these species are not completely understood, and the elucidation of these mechanisms is fundamental to the recommendations of alternative herbicides to glyphosate tolerant weed management. Therefore, the objectives of this research were: (i) to evaluate the weed seed bank dynamic of the species Commelina benghalensis L., Ipomoea grandifolia (Dammer) O’Don and Richardia brasiliensis Gomez (tolerants to glyphosate), Amaranthus hybridus L. and Galinsoga parviflora Cav. (susceptibles to glyphosate), in areas that had been intensively treated with glyphosate rates for two consecutive years; (ii) to characterize the glyphosate tolerance mechanisms of C. benghalensis and I. grandifolia, and (iii) to study the efficacy of alternative herbicides in mixture with glyphosate in the control of tolerant weeds. The weed seed bank dynamic was evaluated through soil samples collected periodically, and analysed quantitative and qualitativelly by greenhouse germination test and seeds counting. Experiments were conducted to caracterize the absorption and translocation of 14 C glyphosate by C. benghalensis, I. grandifolia, A. hybridus and Glycine max resistant (R) and susceptible (S) to glyphosate, at 2, 4, 8, 12, 24, 48 and 72 hours after treatment (HAT); and analysing the glyphosate metabolism by the weeds at 72 HAT. Thin layer chromatography was used to determine the chemical composition of the epicuticular layers and eletronic microscopy to caracterize the foliar surface of the weeds. Greenhouse experiment with the alternative herbicides carfentrazone, flumioxazin, sulfentrazone, chlorimuron-ethyl and bentazon were conducted to test aditive, sinergistic or antagonic interactions with glyphosate on the control of the tolerant weeds. After two years of repetitive glyphosate application there was an increase in the weed seed bank of the tolerant species, and a decrease of the weed seed bank of the susceptible species to glyphosate. The rate of absorption and translocation of the 14 C glyphosate by A. hybridus and Glycine max R and S was higher than the other studied plants, likewise I. grandifolia presented an excelent rate of absorption, even tough, the translocation of this species was reduced. In C. benghalensis the glyphosate rate of foliar absorption was low, however, there was a free translocation of the herbicide. No glyphosate metabolites were observed in I. grandifolia and A. hybridus, however, in C. benghalensis it was found, besides glyphosate, the aminophosphonic acid (AMPA) metabolite. The cuticle waxes of A. hybridus and I. grandifolia presented predominantly hydrophilic characteristics, and the foliar surface did not present tricomes, being observed a great amount of stomata. The epicuticular waxes of this two weed species presented crystal form only in A. hybridus. In C. benghalensis the waxes were relatively more hidrofobics, which could be influenced on lower penetration of glyphosate; the foliar surface present tricomes and fewer stomata, and these are recovered by epicuticular wax.
7

Studies on genetic properties of porcine parvoviruses

Streck, André Felipe 13 June 2013 (has links) (PDF)
Porcine parvovirus (PPV) is considered to be one of the most important causes of reproductive failure in swine. Fetal death, mummification, stillbirths and delayed return to estrus are some of the clinical signs commonly associated with PPV infection in a herd. The virus genome is considered to be conservative, with substitution rates near to that of their host. However, it has been shown that some parvoviruses exhibit a substitution rate close to that commonly determined for RNA viruses. In this scenario, new PPV phenotypes may reduce the effectiveness of the currently used vaccines, recommending the continuous monitoring of the currently prevalent PPV strains. In addition, a number of novel porcine parvoviruses have been described during the last decade, but the importance and characteristics of these viruses remain unknown. In the present dissertation, three studies were performed to address the PPV genetic variability, to monitor the emergence of new PPV strains and the prevalence of novel parvoviruses. In the first study, recent PPV field isolates from Austria, Brazil, Germany and Switzerland were sequenced and analyzed. These samples, together with sequences retrieved from GenBank, were included in three datasets (viral protein complete gene, viral protein partial gene and non-structural protein complete gene). For each dataset, the nucleotide substitution rate was determined and a molecular clock estimated. The analysis revealed that for the new strains, the amino acids substitutions were located mainly in the viral capsid loops. Only the capsid protein datasets present the higher suitability for phylogenetic analysis. In them, a higher divergence was found, with three well defined clusters. By inferring the evolutionary dynamics of the PPV sequences, a nucleotide substitution rate of approximately 10 -4 substitutions per site per year was found for these datasets. An association of the phylogenetic tree with the molecular clock revealed that the main divergence of the PPV strains for the viral protein ocurred in the last 30 years. In the second study, the population dynamic of PPV isolates from swine herds was analyzed using PPV complete protein gene and partial sequences deposited in GenBank. The population dynamic of the virus was calculated using a Bayesian approach with a Bayesian skyline coalescent model. Additionally, an in vitro model was performed by twenty-one consecutives passages of the Challenge strain (a virulent field strain) and NADL2 strain (a vaccine strain) in PK15 cell-line supplemented with polyclonal antibodies raised against the vaccine strain (negative control was not supplemented). The Bayesian analysis indicated a decrease in the population diversity over the years and the predominance of some PPV strains. In agreement, the in vitro study revealed that a lower number of mutations appeared for both viruses in the presence of anti-PPV antibodies in comparison with the control passages without antibodies. In the third study, tonsils and hearts from 100 pigs were collected in a German slaughterhouse in 2010 and tested for PPV, porcine parvovirus 2 (PPV2), porcine parvovirus 3 (PPV3) and porcine parvovirus 4 (PPV4). Positive samples of PPV, PPV2 and PPV3 were sequenced. PPV was observed in 60/100 hearts and 61/100 tonsils and PPV2 in 55/100 hearts and 78/100 tonsils. PPV3 and PPV4 could not be detected in the heart samples but 20/100 and 7/100, respectively, of the tonsils were tested positive. The phylogenetic analysis of the PPV, PPV2 and PPV3 sequences revealed that the German samples could be divided in at least two clusters or clades for each virus. Altogether, it can be concluded that PPV is continuously evolving. Apparently, PPV vaccines largely used in the last 30 years probably have reduced the genetic diversity of the virus and induced the predominance of strains with distinct capsid profile from the original vaccine-based strain. Moreover, the high prevalence of the PPV, PPV2 and PPV3 and their genetic diversity highlight the importance of the continuous monitoring of these viruses.
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Consequences of intraspecific genetic variation for population dynamics and niche expansion

Agashe, Deepa Ashok 10 June 2011 (has links)
Intraspecific genetic diversity is an important attribute of natural populations and is deemed critical for their adaptive potential and persistence. However, we have limited empirical understanding of the impact of genetic diversity on population performance under different conditions. For my dissertation, I conducted long-term laboratory experiments with populations of the flour beetle Tribolium castaneum to test the consequences of genetic variation for population dynamic stability and niche evolution. In Chapter 1, I show that genetic variation prevented population extinction in a novel habitat. In addition, genetically diverse populations were more stable, both in a novel heterogeneous habitat and in their ancestral habitat. In the ancestral habitat, alleles from a single founding lineage dominated the dynamics, leading to increased stability of genetically diverse populations. However, such as selective effect was not observed in the novel heterogeneous habitat. Therefore, while genetic variation within populations increased their stability and persistence, the magnitude of the impact and its mechanism depended on the selective habitat. In Chapter 2, I ask whether genetic variation also facilitates resource niche expansion, i.e., use of a novel resource. Using stable carbon isotopes, I analyzed diets of beetles sampled from the above experiment and quantified the rate of change in resource use. Contrary to theoretical predictions, I found that genetic variation for resource use had no effect on the rate of niche evolution. Furthermore, behavioral niche expansion accounted for most of the adaptation to the novel resource, and the behavioral change hindered subsequent evolutionary change in resource use. It is thus apparent that in the short term, behavioral plasticity in niche use may impose far greater constraints on niche evolution than the amount of standing genetic variation. Mathematical models predict that intraspecific competition generates selection for niche evolution, and that genetic variation increases the response to selection. Therefore, I hypothesized that the impact of genetic variation on resource niche evolution may depend on the degree of intraspecific competition. In the final chapter of this thesis, I describe results of an experiment to test this hypothesis. I found that genetic variation and competition indeed interacted to increase the rate of niche expansion in T. castaneum, but that their impacts were temporally variable. Furthermore, the two factors acted on different components of niche evolution: while competition only affected the degree of niche expansion, genetic variation also promoted maintenance of individual variation in resource use. In summary, my thesis describes experiments to test for the ecological and evolutionary impacts of intraspecific genetic variation; and its interaction with behavioral plasticity, intraspecific competition, and resource availability. Genetic diversity and behavioral plasticity are common features of living organisms, and therefore it is vital to understand their combined consequences for population ecological and evolutionary dynamics. In addition, natural populations often face intense competition for limited resources. Hence the experimental results presented here can help us to better understand how populations overcome these resource constraints, given their specific genetic composition. Biologists are increasingly aware that the intricate connection between ecological and evolutionary dynamics is important to gain a more complete understanding of population biology. The work described here represents one of the few experiments providing such detailed mechanistic understanding of the interactions between- and consequences of - key ecological and evolutionary parameters. Finally, the results have important implications for conservation biology, because they show that the effects of genetic diversity can vary greatly depending on a number of population and environmental parameters. / text
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Estudo comparativo de duas populações de capivaras (Hydrochaeris hydrochaeris) no município de Pirassununga, SP / Comparative study of two capybara (Hydrochaeris hydrochaeris) populations in the district of Pirassununga, SP

Flavia Carolina Vargas 14 September 2005 (has links)
O presente trabalho teve como objetivo conhecer os fatores que propiciam as grandes densidades ecológicas de capivaras, através da comparação das dinâmicas populacionais de dois agrupamentos, em diferentes localidades do município de Pirassununga, SP (Campus Administrativo da Universidade de São Paulo – USP/Pirassununga e o Centro de Pesquisa e Gestão de Recursos Pesqueiros e Continentais – CEPTA/Ibama), para que futuramente seja possível propor uma metodologia de manejo que promova o controle populacional dessa espécie no Estado de São Paulo. Para tanto, foi realizado o monitoramento populacional de ambos agrupamentos durante 15 meses, através da contagem direta dos animais, constituindo na principal fonte de informação para determinar as dinâmicas populacionais. Adicionalmente realizaram-se as capturas dos indivíduos de ambas populações pelo uso de bretes fixos, para que fossem feitas as pesagens, sexagens e marcações eletrônicas pelo uso de microchips e assim, conhecer a distribuição etária, bem como a proporção entre sexos. O uso de ceva no interior dos bretes, para a atração dos animais, possibilitou a realização das contagens diretas e das capturas e recapturas. Para a análise das dinâmicas populacionais foram realizadas as comparações descritivas e estatísticas das densidades ecológicas das populações e das respectivas classes etárias, além do cálculo da taxa de crescimento das mesmas. A alimentação em ceva apresentou-se influenciada pela hierarquia de dominância social, o que fez com que apenas as parcelas dominantes fossem capturadas. Percebeu-se, através das capturas, que o número de fêmeas apreendidas foi superior ao de machos nas parcelas dominantes das duas populações. Por meio das observações foram detectados indivíduos satélites e subagrupamentos, cuja ocorrência pode caracterizar um sistema biológico de metapopulação. A comparação descritiva e estatística das densidades ecológicas das populações, bem como a comparação das taxas de crescimento revelaram superioridade populacional do agrupamento do CEPTA/Ibama em relação ao Campus da USP/Pirassununga, provavelmente pelo maior número de picos de acasalamentos observados, os quais possivelmente são influenciados pelo tipo de habitat antropizado e abundante em recursos hídricos presente no CEPTA/Ibama. / The present research aimed the knowledge of the factors that allow the high ecological densities of capybaras through the population dynamics comparison of two capybara groups in the district of Pirassununga, SP (Campus Administrativo da Universidade de São Paulo – USP/Pirassununga and Centro de Pesquisa e Gestão de Recursos Pesqueiros e Continentais – CEPTA/Ibama), intending to propose forward a management methodology for capybara population control in the State of São Paulo. The populations monitoring was carried out through direct count of animals during 15 months, which played the main role to determine the population dynamics. Fixed traps were used to allow the weightings, sex definitions and identification through microchips, and also to know the age distribution and sex ratios. It was used bait inside the traps to attract animals and thus make direct counting and capture possible. To analyze population dynamics it was used the population ecological densities comparisons (statistically and descriptively) and also their rates of increase. It was detected social dominance hierarchy inside the traps, thus only the dominant part of population could be caught. Females represented the majority among captured animals. Satellites individuals and new groups were seen during observations and their existence might characterize a biological system of metapopulation. The descriptive and statistic comparisons of population ecological densities, as well as their rates of increase showed population superiority of CEPTA/Ibama’s group probably for its bigger reproduction effort detected, which possibly receives influence of anthropogenic and water abundant habitats of CEPTA/Ibama.
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Análise comparativa das espécies de Anastrepha (Diptera, Tephritidae) em três agroecossistemas no estado de São Paulo / Comparative analysis of Anastrepha (Diptera, Tephritidae) species in three agroecosystems in the State of São Paulo, Brazil

Monique Bárbara Rosa de Oliveira 26 March 2015 (has links)
As moscas-das-frutas estão entre as principais pragas da pomicultura em todo o mundo. Devido à sua importância econômica, os estudos sobre os aspectos ecológicos entre as comunidades moscas-das-frutas são cruciais. Assim, o objetivo deste trabalho foi comparar a dinâmica populacional das espécies de Anastrepha em três agroecossistemas diferentes, de três municípios do estado de São Paulo: área antropizada em Piracicaba, área natural em Monte Alegre do Sul e na área agrícola em Monte Alto. Os levantamentos moscas-das-frutas foram realizados utilizando armadilha do tipo McPhail com atrativo alimentar. As comparações das comunidades de moscas-das-frutas foram baseadas nos índices faunísticos. Um total de 49.583 espécimes foram coletados nos três agroecossistemas, pertencentes a 22 espécies. Anastrepha fraterculus e A. sororcula foram predominantes em todos os três agroecossistemas. Anastrepha bahiensis e A. grandis também foram predominantes na área natural, mas na área antropizada apenas A. pseudoparallela foi predominante. Todas essas espécies foram classificadas como super quanto à dominância, abundância, frequência e constância. Embora o índice de diversidade foi elevado na área antropizada, o maior índice de riqueza (Margalef) foi na área natural. Pelo índice de equitabilidade (Pielou), a distribuição das espécies foi mais uniforme na área agrícola. Para a diversidade beta, determinada pelo coeficiente de similaridade (Sørensen), áreas antropizada e natural tiveram 80% de similaridade, diferindo estatisticamente da semelhança com a área agrícola. No entanto, com base no coeficiente de Bray-Curtis, a área natural foi a mais dissimilar, diferindo das áreas antropizada e agrícola. Com base na distância euclidiana, A. fraterculus teve forte interação nos três agroecossistema. De acordo com os índices de diversidade nos três agroecossistemas, a área agrícola, onde foram usados tratamentos fitossanitários, diferiu significativamente das áreas antropizada e natural, tanto na diversidade alfa como beta. / Fruit flies are among the main pests of the pomiculture worldwide. Due to their economic importance, studies on the ecological aspects among fruit fly communities are crucial. Thus, the objective of this work was to compare the population dynamics of Anastrepha species in three different agroecosystems of three municipalities of the state of São Paulo, Brazil: anthropic area in Piracicaba, natural area in Monte Alegre do Sul and agricultural area in Monte Alto. Fruit fly surveys were carried out using McPhail-type trap with food attractants. Comparisons of the fruit fly communities were based on faunistic indices. A total of 49.583 specimens were collected in the three agroecosystems divided in 22 species. Anastrepha fraterculus and A. sororcula were predominant in all three agroecosystems. Anastrepha bahiensis and A. grandis were also predominant in the natural areas, but in the anthropic area only A. pseudoparallela was predominant. All these species were classified as super for the indices dominance, abundance, frequency and constancy. Although the diversity index was high in the anthropic area, the highest richness index (Margalef) was in the natural area. The species distribution was more evenly in the agricultural area by the equitability index (Pielou). For the diversity beta, determined by the similarity coefficient (Sorensen), anthropic and natural areas had 80% of similarity, differing statistically from the similarity with the agricultural area. However, based on the Bray-Curtis coefficient, the natural areas was the most dissimilar, differing from the anthropic and agricultural areas. Based on the Euclidean distance, A. fraterculus had strong interaction in the three agroecosystems. According to the diversity indices for the three agroecosystems, the agricultural area, where pesticides were used, differed significantly from the anthropic and natural areas in both alpha and beta diversity.

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