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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.
81

Estoque de carborno em solos sob plantios de eucalipto e fragmento em Cerrado

Rufino, Ana Maria Martins [UNESP] 28 May 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-05-28Bitstream added on 2014-06-13T20:40:16Z : No. of bitstreams: 1 rufino_amm_me_botfca.pdf: 2747239 bytes, checksum: cdbcc49d429a0f7df7aba9d1fac59f81 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O sequestro de carbono nos ambientes terrestres, sendo feito de forma natural pelos vegetais através da fotossíntese, cujo processo permite fixar o carbono nos solos e, em forma de matéria lenhosa nas plantas, vem sendo apontado como uma alternativa mitigadora das mudanças climáticas, segundo acordos internacionais como o Protocolo de Kyoto. A retirada da floresta nativa provoca a diminuição significativa da biomassa microbiana e da fertilidade do solo. A reserva de carbono na matéria orgânica do solo é uma importante estratégia para atenuar a concentração de CO2 na atmosfera. Com o reflorestamento dessas áreas ocorre uma recuperação lenta e contínua da quantidade e qualidade da matéria orgânica. O eucalipto é a essência florestal mais plantada no Brasil e essas plantações florestais com eucalipto poderão cumprir o papel de aumentar as concentrações de carbono orgânico no solo, recuperando estruturas perdidas quando da exportação da madeira através da colheita, bem como, provocando mudanças ambientais associadas. Este trabalho objetivou quantificar a fixação de carbono no compartimento do solo de 0 a 60 cm de uma floresta nativa em comparação com plantios de eucalipto com 3 diferentes idades: 0 a 1 ano (área recém implantada); 3 a 4 anos (metade do ciclo) e 6 a 7 anos (época de corte). Foram escolhidos quatro diferentes sítios de amostragem com uma área amostral de 1 ha cada. Foram coletadas amostras de solo no inverno e no verão a diferentes profundidades para que se pudesse conhecer a quantidade de carbono orgânico fixado ao longo do perfil do solo considerando o fator da sazonalidade. Os resultados indicam que o manejo nas áreas interferiu no acúmulo de carbono no solo dos quatro sítios estudados, mostrando também que o fragmento de Cerrado estoca menos carbono que os plantios de eucalipto. Quanto à sazonalidade, houve diferença significativa... / The carbon sequestration in terrestrial environments, by plants through photosynthesis, allows carbon fixing as a woody matter in plants. This process has been identified as an alternative to mitigate climate change, according to Kyoto Protocol, an international environmental agreement. The removal of the native forest causes a significant decrease of microbial biomass and soil fertility. The storage of carbon in soil organic matter is an important strategy to reduce the concentration of CO2 in the atmosphere. With the reforestation of these areas, occurs a slow and continuous recovery of the quantity and quality of organic matter. The eucalyptus is the most planted species in Brazil for industrial supply. These eucalyptus reforestations may fulfill the role of increasing soil organic carbon concentration, recovering some structures lost by wood harvesting and causing associated environmental changes. This study aimed to quantify the carbon fixation within the soil compartment from 0 to 60 cm depth of a native forest formation in comparison with eucalyptus plantations with 3 different ages: 0 to 1 year (newly planted area); 3 to 4 years (half the harvesting cycle) and 6 to 7 years (harvesting time). Four different sites were chosen for sampling, with a sampling area of 1 ha each. Soil samples were collected in winter and summer time, at different depths, to quantify the organic carbon fixed throughout the soil profile, considering the seasonality factor. The results indicate that management in each area interfered in the accumulation of carbon in the soil in the four sites studied. The savanna fragment stored less carbon than the eucalyptus plantations. Regarding seasonality, a significant difference was found between the accumulation of carbon in winter and summer... (Complete abstract click electronic access below)
82

Variabilidade genética de população selecionada e teste de paternidade de uma progênie de polinização aberta de Eucalyptus Grandis Hill ex Maiden

Siqueira , Leandro de [UNESP] 02 October 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-10-02Bitstream added on 2014-06-13T18:40:23Z : No. of bitstreams: 1 siqueira_l_me_botfca.pdf: 207322 bytes, checksum: 7e913115e8637d3ba62aaff4d615e95b (MD5) / A espécie Eucalyptus grandis Hill ex Maiden é atualmente a mais comumente cultivada em projetos comerciais no Brasil devido as excelentes características de qualidade da madeira e o alto incremento volumétrico de madeira, a espécie é plantada como cultivar e também na forma de plantios clonais de seus híbridos interespecíficos. O presente trabalho é um estudo da variabilidade genética de uma população selecionada de Eucalyptus grandis que formam um pomar de sementes clonal originário de Coff’s Harbour – Austrália, Rio Claro e Zimbabwe. Este pomar, de propriedade da empresa Suzano Papel e Celulose S.A., encontra-se estabelecido na Fazenda Santa Eliza, no Município de São Miguel Arcanjo no Estado de São Paulo. Tem também como objetivo analisar um teste de paternidade de uma progênie de polinização aberta de Eucalyptus grandis, cuja a mãe é um dos clones componentes do pomar de sementes citado anteriormente. Os objetivos principais do trabalho foram estudar (i) a variabilidade genética dentro de uma população selecionada de Eucalyptus grandis, por meio de marcadores moleculares microssatélites; (ii) o sistema reprodutivo de uma área de recombinação de genótipos superiores (Pomar de Sementes Clonal) e de entrada de fluxo gênico; (iii) a paternidade de uma progênie superior de Eucalyptus grandis de programa de melhoramento. Os resultados mostraram que a população selecionada apresentou um grande polimorfismo de alelos (na = 12) e grandes distâncias genéticas entre os indivíduos selecionados mostrando alta variabilidade genética; que existe uma pequena taxa de endogamia na população selecionada (6,24%) devida a quantidade de heterozigose observada (Ho = 0,7927) ter sido menor que a esperada (He = 0,8455), e que a população selecionada de Eucalyptus grandis apresentou um sistema reprodutivo intermediário com forte tendência a alogamia (88,2%). / The species Eucalyptus grandis Hill ex Maiden is the most commonly cultivated in commercial plantings in Brazil due to its excellent wood quality characteristics and the high wood volume increment. The species is planted as a cultivar and also by clonal plantings of its interspecific hybrids. The research is a study of the genetic diversity of a Eucalyptus grandis selected population originated from Coff’s Harbour – Australia, Rio Claro – Brazil, and Zimbabwe, set up as a clonal seed orchard. The orchard is of Suzano Papel e Celulose private company, located on Santa Elisa Experimental Station, in São Miguel Arcanjo County, S.P., Brazil. It has also as objective to analyze a paternity test of an open pollinated progeny of Eucalyptus grandis, which mother clone is part of the orchard. The objectives of this research were to study (i) the genetic variability within the one selected population of Eucalyptus grandis, by microsatellite molecular markers; (ii) the mating system of recombination area of superior genotypes (Clonal Seed Orchard) and gene flow; and (iii) the paternity of a superior progeny of Eucalyptus grandis breeding program. The results have shown that the selected population presented a high polymorphism of alleles (na = 12) and large genetic distances between selected individuals showing high genetic variability. There is a small inbreeding rate into the selected population (6.24%) because of the observed heterozigosity (Ho = 0.7927) to be lower than the expected (He = 0.8455). The selected Eucalyptus grandis population presented to have an intermediate mating system with high tendency of alogamy.
83

Influência de idade da árvore na velocidade de propagação de ondas de ultrassom em peças estruturais de madeira de reflorestamento / Influence of the tree age on the velocity of ultrasonic wave propagation and on the modulus of elasticity

Massak, Marcus Vinicius 07 August 2010 (has links)
Orientador: Raquel Gonçalves / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-16T20:25:21Z (GMT). No. of bitstreams: 1 Massak_MarcusVinicius_M.pdf: 5087729 bytes, checksum: 1151f8522e1d2d75694f1f4d3479eca3 (MD5) Previous issue date: 2010 / Resumo: Em 2007 foi aprovada, pela Associação Brasileira de Normas Técnicas (ABNT), norma para classificação de madeira de dicotiledônea (NBR 15521, 2007). Essa norma, elaborada com base em ensaios de espécies tropicais com idade média de 45 anos, propõe a classificação de peças estruturais por meio de faixas de velocidade de propagação de ondas de ultrassom, associadas à faixas de rigidez. Em 2008 iniciou-se a elaboração de norma equivalente para as coníferas. No entanto, de forma geral, as madeiras de reflorestamento vêm sendo comercializadas com bem menos idade do que as espécies nativas indicando a necessidade de, tanto para a norma já aprovada quanto para a norma em estudo, serem obtidas informações a respeito da influência da idade na velocidade de propagação das ondas de ultrassom. Esse estudo é importante uma vez que, caso as variações de velocidade com a idade não forem acompanhadas por variações de propriedades mecânicas a classificação poderia ser afetada. Considerando-se o exposto, o objetivo principal dessa pesquisa foi avaliar a variação da velocidade de propagação de ondas de ultrassom e a variação das propriedades de resistência e de rigidez de peças estruturais (vigas) de Pinus elliottii e de Eucalyptus grandis em função da idade. As variações de idade foram estudadas de duas diferentes maneiras. Para o Pinus elliottii as peças foram retiradas de 12 árvores com 6 diferentes idades e para o Eucalyptus grandis de 5 árvores, todas de 34 anos, considerando a variação da idade em função do posicionamento de retirada das toras em relação a altura do tronco. Os ensaios de ultrassom nas vigas foram realizados utilizando-se a NBR 15521 (2007) e os ensaios de flexão estática utilizando-se a ASTM D198 (2008). Os resultados demonstraram que, para o Pinus elliottii, os parâmetros obtidos por ultrassom (velocidade de propagação das ondas - VLL e coeficiente da matriz de rigidez - CLL) e o módulo de elasticidade (EM) obtido na flexão estática tiveram o mesmo comportamento de variação com a idade. Para o Eucalyptus grandis não foi possível associar a posição de retirada no tronco com a idade, mas VLL, CLL e EM tiveram o mesmo comportamento de variação com a posição de retirada. O módulo de ruptura obtido na flexão estática (fm) não variou com a idade nem com a posição de retirada. As correlações entre os ensaios não destrutivos e destrutivos foram todas estatisticamente significativas, com coeficientes de correlação superiores para o parâmetro de rigidez (EM). Para o Eucalyptus grandis o enquadramento dos resultados de VLL e EM nas faixas de classificação da NBR 15521 (2007) foi realizado aplicando-se coeficiente de redução de 12% (fator de calibração) aos valores de velocidade obtidos na condição saturada / Abstract: In 2007 was approved, by the Brazilian Standard Association (ABNT), standard for hardwood grading (NBR 15521, 2007). This standard, based on tests in tropical species with average age 45 years old, proposes grading the hardwood structural sizes lumber based on the ultrasonic velocity ranges associated to the stiffness ranges. In 2008 it was beginning the studies for developing an equivalent standard for softwoods. However, reforestation wood is, in general, put on the market younger than native wood, so it was important, for the cited standard and for the new one, evaluates the influence of the age on the velocity of wave propagation. This study is important because if the variation of the velocity is not follow by the rigidity variation, the grading will be affected. The aim of this research was to obtain technical information about the influence of the tree age on the velocity of ultrasonic wave propagation and on the stiffness and strength of the Pinus elliottii and Eucalyptus grandis structural beams. The age variation was studied using two ways. For Pinus elliottii the beams was cutting from 12 trees with 6 different ages and for Eucalyptus grandis the beam was obtained from 5 trees, all with 34 years old, considering the different ages as a function of the beam position in the trunk. The ultrasonic tests were performed using the NBR 15521 (2007) and the static bending test using the ASTM D198 (2008). The results showed that, for Pinus elliottii, the parameters obtained by the ultrasonic test (velocity of wave propagation - VLL and rigidity coefficient - CLL) and the modulus of elasticity (EM) obtained in bending test had the same pattern of variation with age. For Eucalyptus grandis it was not possible to associate the position of the beam along the trunk with the age, but VLL, CLL and EM had the same pattern of variation with this position. The modulus of rupture obtained in bending (fm) did not present variation with age or with the extraction position. The correlations between nondestructive tests and destructive tests were all statistically significant, with higher correlation coefficients for the stiffness (EM) than for the strength (fm). To use the grade ranges of the NBR 15521 (2007) to the Eucalyptus grandis was necessary to apply 12% as reduction factor (calibrating) in the velocity values obtained in the saturated condition / Mestrado / Construções Rurais e Ambiencia / Mestre em Engenharia Agrícola
84

Estimativa de propriedades de rigidez da madeira a partir de avaliação acústica na árvore e em toras recém abatidas / Accoustic assessment from the tree and the freshly-felled logs for estimating wood stiffness

Pedroso, Cinthya Bertoldo, 1982- 17 August 2018 (has links)
Orientador: Raquel Gonçalves / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-17T16:58:27Z (GMT). No. of bitstreams: 1 Pedroso_CinthyaBertoldo_M.pdf: 1208192 bytes, checksum: 5bc9a2364d675b24999de25964b5d6d5 (MD5) Previous issue date: 2011 / Resumo: Recentes avanços internacionais indicam a possibilidade de prever, a partir da árvore viva ou em toras recém abatidas, informações estratégicas que podem auxiliar a tomada de decisões econômicas e ambientais e possibilitar utilização mais eficaz da madeira. Estas informações podem ser usadas para classificar as árvores de acordo com as possibilidades de aplicações. Na prática as empresas podem atingir benefícios por meio da aplicação de estratégias baseada na qualidade dos recursos florestais que possuem e nos produtos que desejam comercializar. O objetivo da pesquisa foi verificar a existência de correlações entre propriedades da madeira de espécies florestais plantadas no Brasil (Pinus elliottii, Eucalyptus grandis, Toona ciliata, Clone de Eucalyptus), em termos de rigidez e de resistência, com a velocidade de propagação da onda de ultrassom na árvore e/ou nas toras recém abatidas das quais foram retiradas. Para atingir este objetivo foram realizadas medições de ultrassom em árvores e em toras recém abatidas. As toras foram, então, desdobradas em vigas, as quais foram ensaiadas por ultrassom na condição saturada. As vigas passaram por processo de climatização até atingirem 12% de umidade e novas medições de ultrassom foram realizadas. Após as inferências não destrutivas, as vigas foram ensaiadas à flexão estática com a finalidade de determinar o módulo de lasticidade (EM) e o módulo de ruptura (fm). Os resultados foram avaliados de forma estatística buscando-se correlações entre as respostas de propagação de ondas nas árvores e nas toras recém abatidas com as propriedades de resistência e de rigidez das vigas. Para exemplificar a classificação da madeira a partir do ensaio de ultrassom na árvore ou na tora recém abatida foram utilizadas as faixas de classificação da Norma Australiana AS 2878 (SAA, 1986b). Além disso, verificou-se a existência de correlação entre as velocidades de ultrassom na árvore-tora, árvore-viga e tora-viga, todas na condição saturada. Os resultados obtidos mostraram que é possível obter as propriedades de resistência e de rigidez, assim como, estimar faixa de classificação da madeira a partir da velocidade longitudinal de ultrassom na árvore e/ou da velocidade longitudinal de ultrassom na tora, desde que as mesmas não sejam constituídas essencialmente por madeira juvenil, como foi o caso do clone de eucalipto e do Cedro australiano nessa pesquisa. O modelo de regressão da velocidade árvore-tora foi o que apresentou maior coeficiente de correlação, seguido do modelo de regressão da velocidade tora-viga saturada e, por último, do modelo de regressão da velocidade árvore-viga saturada / Abstract: Recent international advances have pointed out the possibility of estimating, from a live tree or freshly-felled logs, strategic information that may assist in economic and environmental decision making, as well as allowing a more effective application of wood. Such information may be used to classify trees according to their application range. In practice, companies may benefit from that through employing strategies based on the quality of the forest resources they have available and also from the products they intend to market. The aim of this research is to establish whether there is an correlation between the properties of exotic trees growing in Brazil (Pinus elliottii, Eucalyptus grandis, Toona ciliata, Eucalyptus clone) - regarding stiffness and strength - and the velocity of ultrasound wave propagation in the tree and/or freshly-felled logs from which they have been drawn. In order to do so, ultrasound measurements were performed in trees and recently cut logs. Afterwards, logs were unfolded in beams, which in their turn were tested by ultrasound in green condition. Beams underwent an acclimatation process until reaching 12% of moisture content and new ultrasound measurements were performed. Following the nondestructive tests, the beams were tested in static bending in order to establish the modulus of elasticity (EM) and the modulus of rupture (fm). Results were statistically evaluated, seeking correlation between the responses of wave propagation in trees and freshly-felled logs and the beams stiffness and strength properties. As to exemplify wood classification from tree or recently cut log, the Australian Norm AS 2878 (SAA, 1986b) was applied. Further, it was also possible to establish a correlation between ultrasound velocities in tree-log, tree-beam and log-beam, all in green condition. Results obtained showed to be possible to determine stiffness and strength properties as well as to estimate a wood classification layer from ultrasound longitudinal velocity in the tree, and/or ultrasound longitudinal velocity in the freshly-felled logs , unless the wood are essentially made up by juvenile wood, as happened with the eucalyptus clone and the Australian Cedrus in the present research. The model regression tree-log velocity was the one that presented the highest correlation coefficient, followed by the regression saturated log-beam velocity and, lastly, the regression saturated tree-beam velocity / Mestrado / Construções Rurais e Ambiencia / Mestre em Engenharia Agrícola
85

Avaliação da calogênese em explantes juvenis de teca (Tectona grandis L. f) visando a indução da embriogênese somática / Evaluation of callus induction in juvenile explants of teak (Tectona grandis L. f) attempting to induce somatic embryogenesis

Renato da Silva Barbosa 15 January 2015 (has links)
A teca (Tectona grandis L. f) é uma espécie lenhosa originária da Ásia que possui grande interesse econômico devidos as características nobres de sua madeira. Muito usada para construção de embarcações e móveis de luxo para exposição em ambientes abertos, seu consumo tem aumentado a cada ano, principalmente nos países produtores. Com a pressão das políticas ambientais sobre o uso da madeira de espécies nativas, a teca se mostra uma ótima alternativa para o mercado de madeira serrada. Contudo, a produção comercial desta espécie encontra algumas barreiras, sendo a principal delas, a propagação de matrizes adultas cujas características se adequam ao manejo silvicultural. Para possibilitar a reprodução fiel das árvores selecionadas e, para se realizar o rejuvenescimento do material adulto procedente dessas matrizes, faz-se uso de algumas técnicas, sendo uma delas, o uso da cultura de tecidos. Uma maneira bastante considerada no processo de rejuvenescimento e obtenção de mudas de espécies agrícolas e florestais é a formulação de protocolos de embriogênese somática. A embriogênese somática pode ser descrita como o processo pelo qual células somáticas desenvolvem estruturas semelhantes a embriões zigóticos, por meio de uma sequência ordenada de estágios embriogênicos característicos, sem ocorrência de fusão de gametas. Para tanto, o desenvolvimento de um protocolo eficiente de tal técnica exige muitos estudos preliminares. Com isso, o presente trabalho teve como objetivo estudar a calogênese em diferentes explantes de teca, através de uma sequência de indução utilizando difrentes fitorreguladores visando a obtenção de embriões somáticos. Para avaliar a resposta dos calos a cada etapa da indução foram realizadas análises histológica e histoquímica dos tecidos. Como respostas foram encontrados os balanços auxina/citocinina mais adequado para produção de calos, sendo eles 1,5/1,0 e, 1,5/4,0mgL-1 de picloram e BAP respectivamente. Verificou-se que o pulse com TDZ foi responsivo na obtenção de massas próembriogênicas, e que o uso da zeatina e da glutamina, não favorecem a maturação de tais estruturas, além de ocasionarem a morte celular programada das células da massa calosa. Contudo, os resultados mostram-se positivos e auxiliam na formulação de novos tratamentos e técnicas de indução da embriogênese somática para a espécie estudada. / Teak (Tectona grandis L. f) is a native woody species from Asia that has great economic interest due the noble characteristics of its wood. Widely used for building ships and luxury furniture for display outdoors, their consumption has increased every year, especially in producing countries. With the pressure of environmental policies on the use of native species of wood, teak shown a great alternative to the market for lumber. However, commercial production of this species has some barriers, the main one, being the propagation of mature breeders whose characteristics are suited to forestry management. In order to enable the faithful reproduction of the selected trees, and to perform the rejuvenation of these matrices derived of adult material, some techniques can be used, one of them is the use of tissue culture. Considered in a way quite rejuvenating and seedlings of agricultural and forest species process is the formulation of somatic embryogenesis protocols. Somatic embryogenesis can be described as the process by which somatic cells develop structures similar to zygotic embryos, through an ordered sequence of characteristic embryogenic stages without occurrence of the fusion of gametes. Thus, the development of an efficient protocol for this technique requires a lot of preliminary studies. Thus, the present work aimed to study the callus induction in different explants of teak, through a sequence induction using different growth regulators in order to obtain somatic embryos. To assess the response of each stage during callus induction, histological and histochemical tissue analysis were performed. Responses as the most suitable for callus production auxin / cytokinin balance sheets were found, they 1.5 / 1.0 and 1.5 / 4,0mgL-1 picloram/BAP, respectively. It was found that TDZ pulse was responsive to obtain pro-embryogenic masses, and that the use of zeatin and glutamine, are not conducive to maturation of such structures, and enacting the programmed cell death of the cell calli mass. However, the results show up positive and assist in the formulation of new treatments and techniques for induction of somatic embryogenesis of this species.
86

Sensibilidade in vitro de isolados de Alternaria grandis e Alternaria solani a fungicidas / In vitro sensitivity of Alternaria grandis and Alternaria solani to fungicides

Shadia Katari Nossllala 07 February 2017 (has links)
Atualmente, a produtividade da cultura da batata (Solanum tuberosum L.) pode ser reduzida devido à ocorrência de doenças em todo o território nacional, destacando-se a pinta preta, causada por Alternaria spp. Historicamente se acreditava que A. solani (AS) era a principal causadora mas, atualmente, descobriram outras espécies associadas, sendo predominante hoje, em território nacional a espécie A. grandis (AG). O objetivo deste trabalho foi avaliar a sensibilidade in vitro de três isolados de A. grandis e um isolado de A. solani frente a onze fungicidas amplamente utilizados no manejo desta doença em campo. Foi avaliado o efeito dos fungicidas sobre o crescimento micelial dos isolados, utilizando-se do método da incorporação do fungicida no meio de cultura fundente. As diluições dos fungicidas foram realizadas em água destilada e esterilizada, de acordo com a metodologia descrita por Camargo (2013) e Ishizuka (2016). Para os fungicidadas com mistura de ingrediente ativo, considerou-se a soma das concentrações no cálculo. Inicialmente, as concentrações do meio de cultura, foram 100, 10, 1, 0,1, 0,01 e 0,001 mg L-1. Após, as doses foram ajustadas conforme a CI50 de cada fungicida. Quantificou-se também a inibição sobre a germinação dos conídios nas contrações discriminatórias de 0; 0,1; 1; 10 e 100 mg.L-1 .24 horas após o preparo do meio as placas foram observadas em microscópio óptico, determinando-se a germinação dos conídios em 300 unidades observadas por placa de Petri. Todos os isolados testados foram altamente sensíveis aos ingredientes ativos fluazinam, pirimetanil, procimidona e piraclostrobina. Não houve diferenças de comportamento de sensibilidade entre as espécies de A. solani e A grandis que possam caracterizar uma perda de sensibilidade por conta da predominância da espécie de A. grandis associada à pinta preta da batata no Brasil. Encontraram-se evidências de insensibilidade dos isolados de A. grandis e A. solani aos ingredientes ativos Clorotalonil e Boscalida. / Currently, the productivity of potato crop (Solanum tuberosum L.) may be reduced due to the occurrence of disease throughout the country, especially due to early blight, caused by Alternaria spp. Historically it was believed that A. solani (AS) was the main cause, most currently was founded others associated species, being predominant today the occurrence of the disease associated with the species A. grandis (AG). The objective of this study was to evaluate the in vitro susceptibility of three isolates of A. grandis and one isolate of A. solani for eleven fungicides widely used in the management of this disease in the field, was evaluated the effect of fungicides on mycelial growth using the fungicidal method that incorporate it in the medium culture. Dilutions of fungicides were performed in sterile distilled water according to the methodology described by Camargo (2013) and Ishizuka (2016). For the fungicidates with active ingredient mixture, was considered the sum of the both concentrations in the calculation.The concentrations of the culture medium were 100, 10, 1, 0.1, 0.01 and 0.001 mg L-1. The doses were adjusted according to the CI50 of each fungicide, was quantified also the inhibition of spore germination, and the fungicides were incorporated into the agar medium - water in discriminatory contractions of 0; 0.1; 1; 10 and 100 mg.L-1 . Then, 24 hours after preparation of the medium the plates were observed under an optical microscope, determining the spore germination observed at 300 units per plate. All tested isolates were highly sensitive to the active ingredients fluazinam, pyrimethanil, procymidone and pyraclostrobin. There was no sensitivity behavioral differences between species of A. solani and A. grandis which may characterize a loss of sensitivity due to the predominance of species of A. grandis associated with early blight in Brazil, was found evidences of insensitivity of isolates of A. grandis and A. solani to the active ingredients Chlorothalonil and Boscalida.
87

Características biométricas, trocas gasosas e atividade do sistema antioxidante de plantas de eucalipto durante o cres- cimento inicial / Biometric characteristics, gas exchange and oxidant system activity of eucalyptus plants during the inicial growth

Delias, Dominique dos Santos 01 March 2013 (has links)
Made available in DSpace on 2014-08-20T13:59:06Z (GMT). No. of bitstreams: 1 dissertacao_dominique_dos_santos_delias.pdf: 964673 bytes, checksum: 892fa8709ea83828fd81eed2a68b8b79 (MD5) Previous issue date: 2013-03-01 / Eucalyptus is a genus with origin in Australia and has expanding in several regions of Brazil, mainly due to its wide aclimatation. But there are certain regions with climatic characteristics that may limit the growth and development of eucalyptus plants, resulting in abiotic stress. In this context, monitoring the inicial growth of plants allows us a better understanding about species that survive better against the heterogeneous environment, enabling the good quality seedlings production. This work aimed to analyze the behavior of biometric characteristics, gas exchange and the antioxidant system activity of plants of two species of Eucalyptus, E. grandis and E. saligna during inicial growth. Samples were collected monthly between 2011 July and 2012 July. On 2011 May, nursery seedlings were transplanted to 5 L plastic bags, containing a mixture of soil and sand (2:1). We evaluated biometric characteristics (stem diameter at 10 cm from the soil, diameter at half height of the plant stem, plant height, leaf number, leaf area and dry weight of leaf, stem, root and total dry weight), biochemical characteristics (activity of Superoxide Dismutase, Catalase and Ascorbate Peroxidase enzymes, quantification of hydrogen peroxide and lipid peroxidation) and gas exchange (rate of CO2 assimilation, intracellular concentration of CO2, stomatal conductance and transpiration). The results showed that E. saligna had higher growth than E. grandis. Regarding biochemical analyzes, E. grandis had higher activity of antioxidant enzymes at the beginning and end of the experiment, that represents the cold seasons. E. saligna showed increased activity only in the second season of cold. For gas exchange differences occurred between species and between the evaluations times. In general, it was found that plants E. grandis and E. saligna showed similar responses face of climatic conditions of the region studied, and this research confirms their initial growth adaptability to climatic conditions of Rio Grande do Sul State. / Eucalyptus é um gênero originário da Austrália e vem apresentando rápida expansão em várias regiões do Brasil, devido principalmente a sua ampla capacidade de aclimatação. Porém existem regiões que apresentam determinadas características climáticas que podem limitar o crescimento e o desenvolvimento dessas plantas, resultando em estresse abiótico. Nesse contexto, monitorar o crescimento inicial de mudas permite conhecer espécies que melhor sobrevivem frente ao ambiente heterogênio, possibilitando a produção de mudas de boa qualidade. Este trabalho teve por objetivo analisar o comportamento das características biométricas, trocas gasosas e atividade do sistema antioxidante de plantas de duas espécies de eucalipto, Eucalyptus grandis e E. saligna, durante o crescimento inicial. As coletas foram realizadas mensalmente de julho de 2011 a julho de 2012. Mudas provenientes de viveiro foram transplantadas, no mês de maio de 2011, para sacos plásticos de 5L, contendo uma mistura de terra e areia (2:1). Foram avaliadas características biométricas (diâmetro do caule a 10 cm da base e na metade da altura da planta, altura, número de folhas, área foliar e massa seca das folhas, caule, raízes e total), bioquímicas (atividade das enzimas Superóxido Dismutase, Catalase e Ascorbato Peroxidase, quantificação de peróxido de Hidrogênio e peroxidação lipídica) e trocas gasosas (taxa assimilatória líquida de CO2, concentração intracelular de CO2, taxa transpiratória e condutância estomática. Os resultados demonstraram que E. saligna apresentou maior crescimento quando comparado com E. grandis. Em relação às analises bioquímicas, E. grandis teve maior atividade das enzimas antioxidantes no início e no final do experimento, coincidindo com as épocas de frio, diferindo de E. saligna que apresentou aumento na atividade só no segundo ciclo de frio. Para trocas gasosas, houve diferença entre as espécies e entre os tempo de avaliação. De maneira geral, verificou-se que plantas de E. grandis e E. saligna apresentaram respostas semelhantes frente às condições climáticas da região estudada, e as pesquisas de crescimento inicial confirmam sua adaptabilidade às condições climáticas do Rio Grande do Sul.
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The estimation of Eucalyptus plantation forest structural attributes using medium and high spatial resolution satellite imagery.

January 2008 (has links)
Sustaining the socioeconomic and ecological benefits of South African plantation forests is challenging. A more systematic and rapid forest inventory system is required by forest managers. This study investigates the utility of medium (ASTER 15 m) and high (IKONOS 1-4 m) spatial resolution satellite imageries in an effort to improve the remote capture of structural attributes of even-aged Eucalyptus plantations grown in the warm temperate climatic zone of southern KwaZulu-Natal, South Africa. The conversion of image data to surface reflectance is a pre-requisite for the establishment of relationships between satellite remote sensing data and ground collected forest structural data. In this study image-based atmospheric correction methods applied on ASTER and IKONOS imagery were evaluated for the purpose of retrieving surface reflectance of plantation forests. Multiple linear regression and canonical correlation analyses were used to develop models for the prediction of plantation forest structural attributes from ASTER data. Artificial neural networks and multiple linear regression were also used to develop models for the assessment of plantation forests structural attributes from IKONOS data. The plantation forest structural attributes considered in this study included: stems per hectare, diameter at breast height, mean tree height, basal area, and volume. In addition, location based stems per hectare were determined using high spatial resolution panchromatic IKONOS data where variable and fixed window sizes of local maxima were employed. The image-based dark object subtraction (DOS) model was better suited for atmospheric correction of ASTER and IKONOS imagery of the study area. The medium spatial resolution data were not amenable to estimating even-aged Eucalyptus forest structural attributes. It is still encouraging that up to 64 % of variation could be explained by using medium spatial resolution data. The results from high spatial resolution data showed a promising result where the ARMSE% values obtained for stems per hectare, diameter at breast height, tree height, basal area and volume are 7.9, 5.1, 5.8, 8.7 and 8.7, respectively. Results such as these bode well for the application of high spatial resolution imagery to forest structural assessment. The results from the location based estimation of stems per hectare illustrated that a variable window size approach developed in this study is highly accurate. The overall accuracy using a variable window size was 85% (RMSE of 189 trees per hectare). The overall findings presented in this study are encouraging and show that high spatial resolution imagery was successful in predicting even-aged Eucalyptus forest structural attributes in the warm temperate climates of South Africa, with acceptable accuracy. / Thesis (Ph.D.) - University of KwaZulu-Natal, Pietermaritzburg, 2008.
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Assessment of structural attributes of even-aged Eucalyptus grandis forest plantations using small-footprint discrete return lidar data.

Tesfamichael, Solomon Gebremariam. January 2009 (has links)
Assessment of forest structural attributes has major implications in the management of forestry by providing information of ecological and economic importance. The traditional methods of assessment involve collecting data in the field and are regarded as labour-intensive and expensive. In plantation forestry, field campaigns are generally time consuming and costly, and may compromise profit maximisation. The introduction of lidar (light detection and ranging) remote sensing in forestry has shown promise to add value to the traditional field inventories mainly through large spatial coverages in a timely and cost-effective manner. Lidar remote sensing is an advanced system capable of acquiring information in both the vertical and horizontal dimensions at relatively high resolutions. Numerous studies have established that these qualities of lidar data are suited to estimating forest structural attributes at acceptably high accuracies. The generic approach in most studies is to use lidar data in combination with field data. Such an approach still warrants a high cost of inventory. It is therefore useful to explore alternative methods that rely primarily on lidar data by reducing the necessity for field-derived information. The aim of this study was to derive structural attributes of even-aged Eucalyptus grandis forest plantations using lidar data. The attributes are of significance to timber resource assessments and include plot-level tree height attributes, stems per hectare (SPHA), and volume. The surveyed field data included tree counting and measurement of tree height and diameter at breast height for sample plots. Volume was then calculated using standard allometric models. Small-footprint lidar data of the plantations were also acquired coincident with the field inventories. Mean tree height and dominant height were estimated at a range of simulated lidar point densities between 0.25 points/m2–6 points/m2. Various plot-level distributional metrics were extracted from height values of lidar non-ground points and related with field mean and dominant height values using stepwise regression analysis. The results showed that both attributes could be estimated at high accuracies with no significant differences arising from variations in lidar point density. Estimation of SPHA relied on the exploration of semi-variogram range as a mean window size for applying local maxima filtering to the lidar canopy height surface. A comparative approach of window size determination used pre-determined within-row tree spacing, based on planting information. Two secondary objectives were addressed: comparing spatial resolutions of canopy height surfaces interpolated from non-ground height values and comparison of lidar point densities simulated at three levels. Comparison of spatial resolutions of canopy height surfaces were performed at 0.2 m, 0.5 m, and 1 m using a lidar point density of 5 points/m2. The results indicated that 0.2 m is the most appropriate resolution for locating trees and consequently deriving SPHA. Canopy height surfaces of 0.2 m resolution were created at simulated densities of 1 point/m2, 3 points/m2, and 5 points/m2. While all estimates were negatively biased relative to field-observed SPHA, lidar densities of 3 points/m2 and 5 points/m2 returned similar accuracies, which were both superior to 1 point/m2. It was concluded that 3 points/m2 was sufficient to achieve the accuracy level obtained from higher lidar point densities. Plot-level mean height, dominant height, and volume of trees were estimated for trees located using local maxima filtering approaches at the three lidar point densities. Mean height and dominant height were both estimated at high accuracies for all local maxima filtering techniques and lidar point densities. The results were also comparable to the approach that employed regression analysis that related lidar-derived distributional metrics and field measurements. Estimated dominant height and SPHA, as well as age of trees, were used as independent variables in a function to estimate plot-level basal area. The basal area was then used to compute diameter of the tree with mean basal area, referred to as quadratic mean diameter at breast height (QDBH). Mean tree height and QDBH were used as independent variables in a standard equation to calculate mean tree volume, which was then scaled up to the plot-level. All estimates for the local maxima filtering approaches and lidar point densities returned negatively biased volume, when compared to field observations. This was due to the underestimation of SPHA, which was used as a conversion factor in scaling up from tree-level to plot-level. Volume estimates across lidar point densities exhibited similarities. This suggests that low lidar point densities (e.g., 1 point/m2) have potential for accurate volume estimation. It was concluded that multiple forest structural attributes can be assessed using lidar data only. The accuracy of height derivation meets the standards set by field inventories. The underestimation of SPHA may be comparable to other studies that applied different methods. However, improved estimation accuracy is needed in order to apply the approaches to commercial forestry scenarios. The significance of improving SPHA estimation extends to improved volume estimation. In addition, the potential improvement should also take into consideration the density of lidar points, as this will impact on the cost of acquisition. This research has taken a significant step towards determining if lidar data can be used as a stand-alone remote sensing data source for assessment of structural plantation parameters. Not only does such an approach seem viable, but the lower required point densities will help to reduce acquisition costs significantly. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
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In Vitro Incubation of Gills Isolated from the Gulf Killfish, Fundulus Grandis

Diaz, Joseph Anthony 01 May 2014 (has links)
The use of viable and reliable tissue preparations allows for experimental approaches in vitro that would not be possible in vivo. In this experiment, gills were isolated from gulf killifish, Fundulus grandis, and subjected to various incubation conditions. A combination of two types of media and two incubation apparatuses were compared in their ability to sustain tissues, as measured by the vital stain trypan blue (TB) and percent lactate dehydrogenase (LDH) leakage. Trypan Blue analysis indicated no significant difference in tissue viability, regardless of the treatment or incubation time. However, percent LDH leakage analysis revealed that the two most influential variables were the medium and apparatus in which the gills were incubated. Interestingly, incubation time did not have a statistically significant influence on gill viability as measured by LDH leakage. The results of LDH leakage analysis suggest that incubation using SW in the 4 ml apparatus is the best combination tested.

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