1000 resultados para Pinus spp - Plantio


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A redução da disponibilidade de espécies de madeiras nativas e seus efeitos na economia, associada ao fortalecimento dos conceitos de preservação ambiental, criou a necessidade de desenvolvimento de alternativas viáveis para utilização racional de espécies de reflorestamento. E uma das opções é a realização de classificação visual das peças. Autores de trabalhos desenvolvidos nessa linha de pesquisa verificaram a adequação das regras de classificação visual do Southern Pine Inspection Bureau (SPIB) dos EUA à madeira de Pinus do Brasil e apresentaram proposta para normalizar o processo de classificação visual dessa madeira. Nessa classificação, os aspectos com maior influência são: presença de nós, desvio de grã em relação ao eixo da peça e densidade de anéis de crescimento. Assim, esta pesquisa apresenta um estudo experimental que consistiu na classificação visual e determinação da resistência à tração de 85 peças de Pinus spp e um estudo teórico, que propôs uma equação para determinar a resistência à tração média de peças estruturais em função da classificação visual. Com este trabalho, foi possível observar a influência dos nós e dos anéis de crescimento sobre a resistência à tração das peças analisadas.

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Dissertação apresentada para obtenção do Grau de Doutor em Ciências do Ambiente pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecn

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A population survey of the giant conifer aphid Cinara spp. was carried out in two areas of Pinus elliottii using yellow pan traps, during two years, from July 1997 to June 1999. During the collection period, the predominant species was Cinara pinivora (Wilson, 1919), representing 99% of the collected species. A few specimens of Cinara maritimae (Dufour, 1833) and only one winged female of Cinara fresai Blanchard, 1939 were collected. The population of C. pinivora was statistically higher in the area with 4.5 year-old trees than in the 1.5 year-old ones. The highest population peaks were registered in July 1997 and in August 1998. An unexpected high number of winged parthenogenetic females was collected in December 1998. C. fresai Blanchard, 1939 is recorded for the first time for Brazil.

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A redução da disponibilidade de espécies de madeiras nativas e seus efeitos na economia, associada ao fortalecimento dos conceitos de preservação ambiental, criou a necessidade de desenvolvimento de alternativas viáveis para utilização racional de espécies de reflorestamento. E uma das opções é a realização de classificação visual das peças. Autores de trabalhos desenvolvidos nessa linha de pesquisa verificaram a adequação das regras de classificação visual do Southern Pine Inspection Bureau (SPIB) dos EUA à madeira de Pinus do Brasil e apresentaram proposta para normalizar o processo de classificação visual dessa madeira. Nessa classificação, os aspectos com maior influência são: presença de nós, desvio de grã em relação ao eixo da peça e densidade de anéis de crescimento. Assim, esta pesquisa apresenta um estudo experimental que consistiu na classificação visual e determinação da resistência à tração de 85 peças de Pinus spp e um estudo teórico, que propôs uma equação para determinar a resistência à tração média de peças estruturais em função da classificação visual. Com este trabalho, foi possível observar a influência dos nós e dos anéis de crescimento sobre a resistência à tração das peças analisadas.

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A busca por novas tecnologias que garantam a uniformidade da qualidade dos produtos tem se tornado constante, assim este trabalho teve como objetivo estudar a potencialidade de medidas espectroscópicas combinadas a ferramentas estatísticas para classificação de lâminas de madeiras de Pinus spp. contaminadas por fungos manchadores. As amostras foram coletadas em processo industrial, e observou-se que algumas lâminas estavam contaminadas por fungos manchadores. Assim, utilizou-se este material para investigar a influência dessa mancha azul em metodologias espectroscópicas e a possibilidade de discriminação dessa contaminação. Desse material contaminado foram capturados os espectros, na faixa de 400 a 1000 nm. Com esses dados, realizou-se uma análise exploratória por Componentes Principais (PCA) e classificação via SIMCA, em que se verificou a discriminação eficiente em dois grupos, madeiras sadias e contaminadas. Observou-se que a técnica de espectroscopia óptica preenche os requisitos necessários para uma possível aplicação na classificação de lâminas no processo produtivo.

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[Tesis] (Doctor en Ciencias con Especialidad en Manejo de Recursos Naturales) U.A.N.L.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Aim of study: Tuber aestivum is the most widespread edible truffle, with increasing commercial interest. This species can produce carpophores with conifer hosts, in contrast with the inability of Pinus spp. to induce fruiting in other truffle species such as Tuber melanosporum. Therefore the objective is to compare the characteristics and carpophore production of T. aestivum brûlés associated with Pinus spp. versus Quercus spp. Area of study: We studied the natural habitats of T. aestivum in the Alto Tajo Nature Reserve in central Spain. Material and methods: During 5 years, we monitored the production of carpophores and brûlé size of 145 T. aestivum brûlés associated with Pinus nigra subsp. salzmanni and P. sylvestris and Quercus ilex subsp. ballota and Q. faginea hosts. Statistical treatment was performed using the Statistica Program v. 6. Main results: The size of brûlés associated with Pinus was significantly smaller than that of brûlés associated with Quercus. However, carpophore production per brûlé, and especially for brûlés of similar size, was greater when the host plant was a pine. After accounting for brûlé size, the production of brûlés associated with Pinus spp. was 2.23 (95% CI, between 1.35 and 3.69) and 1.61 (95% CI, between 1.02 and 2.54) times greater than the production of brûlés associated with Quercus faginea and Q. ilex subsp. ballota, respectively. Research highlights: The considerable ability of Pinus nigra subsp. salzmanni and P. sylvestris to form effective brûlés and to produce carpophores of Tuber aestivum in natural conditions was clearly demonstrated, and suggest that those species can be of use in the culture of T. aestivum.

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Pine forests constitute some of the most important renewable resources supplying timber, paper and chemical industries, among other functions. Characterization of the volatiles emitted by different Pinus species has proven to be an important tool to decode the process of host tree selection by herbivore insects, some of which cause serious economic damage to pines. Variations in the relative composition of the bouquet of semiochemicals are responsible for the outcome of different biological processes, such as mate finding, egg-laying site recognition and host selection. The volatiles present in phloem samples of four pine species, P. halepensis, P. sylvestris, P. pinaster and P. pinea, were identified and characterized with the aim of finding possible host-plant attractants for native pests, such as the bark beetle Tomicus piniperda. The volatile compounds emitted by phloem samples of pines were extracted by headspace solid-phase micro extraction, using a 2 cm 50/30 mm divinylbenzene/carboxen/polydimethylsiloxane table flex solid-phase microextraction fiber and its contents analyzed by high-resolution gas chromatography, using flame ionization and a non polar and chiral column phases. The components of the volatile fraction emitted by the phloem samples were identified by mass spectrometry using time-of-flight and quadrupole mass analyzers. The estimated relative composition was used to perform a discriminant analysis among pine species, by means of cluster and principal component analysis. It can be concluded that it is possible to discriminate pine species based on the monoterpenes emissions of phloem samples.

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The giant conifer aphids Cinara pinivora (Wilson, 1919) and Cinara atlantica (Wilson, 1919) (Hemiptera, Aphididae) have been observed attacking Pinus spp. in Southern and Southeastern Brazil. The coccinellids, on the other hand, were found feeding on these aphids in the field, which can be regarded as potential biological control agents. The biological cycle and mortality rate of larvae of Cycloneda sanguinea (Linnaeus, 1763) and Hippodamia convergens Guérin-Méneville, 1842 (Coleoptera, Coccinellidae) were evaluated using twenty larvae of each predator species fed with nymphs of Cinara. The vials with the insects were kept under 15 ºC, 20 ºC and 25 ºC, with 12h photophase and 70 ± 10% relative humidity. The consumption was evaluated every 24 hours and the nymphs replaced. For C. sanguinea, the egg incubation time was 10.5, 5.0 and 4.0 days; the average larval development period was 33.3, 15.8 and 8.6 days and the larval mortality rate 20%,0% and 15%, respectively at 15 ºC, 20 ºC and 25 ºC. For H. convergens, the larval development time was 41.9, 19.3 and 10.9 days at 15 ºC, 20 ºC and 25 ºC, respectively. The larval mortality rate was 35%, 15% and 0% under the three temperatures. Both species developed adequately when fed nymphs of Cinara, however, C. sanguinea performed better than H. convergens, even at 15 ºC, at which temperature the biological cycles of the coccinellids are prolonged, but the temperature is favorable for the development of Cinara populations in the field.

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Adults and larvae of coccinellids were observed feeding on populations of the giant conifer aphids Cinara spp. on Pinus spp., in Southern Brazil. The objective of this research is to evaluate the consumption capacity of Cycloneda sanguinea (Linnaeus, 1763) and Hippodamia convergens Guérin-Méneville, 1842 (Coleoptera, Coccinellidae) on these aphid species, in order to obtain information for biological control programs. Ten larvae of each predator species were fed with aphids of small size (nymphs of 1st and 2nd instars), and 10 with aphids of medium size (nymphs of 3rd and 4th instars), maintained under 15ºC, 20ºC and 25ºC, 12 h photophase and 70 ± 10% relative humidity. The aphids were counted every 24 hours, replacing those that were consumed. The total consumption of Cinara by the larvae of C. sanguinea was not statistically different at the three temperatures: 325.5; 322.2 and 324.8 of small aphids and 121.3; 140.4 and 109.9 of medium ones, respectively at 15ºC, 20ºC and 25ºC. The consumption by H. convergens was higher than by C. sanguinea and increased noticeably with temperature: 444 aphids at 15ºC; 491.3 at 20ºC and 513.3 at 25ºC, considering the small aphids, and 187.1; 205.1 and 216.6 of medium aphids at the three temperatures. The small aphids weigh about half as much as medium ones and were preferred by all larval instars probably because they are easier to manipulate than the large ones. Both predators, especially the 4th instar larvae, showed high consumption capacity on the Cinara nymphs at all temperatures and can be regarded as promising biological control agents.