244 resultados para Gradiente de salinidade

em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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This study aimed to evaluate the effects of salinity in the growth and nitrogen fixation in leucaena. Plants were cultivated in Leonard pots containing clean and sterilized sand. The treatments were distributed in a completely randomized design, in a 3x3 factorial, with five replicates. The first factor corresponded to no inoculation and inoculation with Bradyrhizobium sp SEMIA 6070 and SEMIA 6153 strains. The second factor corresponded to NaCl concentrations: 0, 25 and 50 mol m(-3). Were analyzed the height and dry matter accumulation, the number of nodules and nitrogen in plants. The inoculation of plants with the strain SEMIA 6070 provided higher growth and greater nitrogen accumulation in plants thar were not subject to salinity. Nodulation was not affected by salinity. Inoculation with SEMIA 6153 strain provided greater tolerance to salinity.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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O objetivo deste trabalho foi avaliar o efeito de diferentes níveis de salinidade de água de irrigação no uso consultivo na fase reprodutiva da bananeira e evolução da salinidade do solo. Adotou-se o delineamento inteiramente casualizado em parcelas subdivididas, totalizando oito tratamentos com quatro repetições por tratamento. Os níveis de salinidade foram obtidos a partir de águas naturais de poços dos aquíferos arenito e calcário e foram misturadas em tanques de alvenaria para a obtenção das concentrações de salinidade desejada. Verificou-se que a área do bulbo com umidade superior a 8% representa aproximadamente 50% do volume do solo. A evapotranspiração da cultura diminuiu com o aumento da salinidade entre os tratamentos, o kc médio no período variou de 1,01 a 1,09 em águas de salinidade extremas. Comparando os perfis da salinidade do solo, verificou-se que a concentração de sais foi superior na camada superficial aos 440 dias após plantio.

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An experiment was carried out in greenhouse during the period January to April 2010, at Center of Agricultural Sciences of the Federal University of Paraiba, in Areia, Paraiba State, Brazil, in order to evaluate the effects of saline water and bovine biofertilizer on the seedling growth of Indian neem. The substrate was material of a non-saline soil collected in depth of 0-20 cm. The treatments were arranged in a completely randomized design using a 5 x 2 factorial, referring to salinity levels of irrigation water of 0.5, 1.0, 2.0, 3.0 and 4.0 dS m(-1), with and without bovine biofertilizer applied to the soil only once after dilution with water (1: 1), a day before sowing, in volume corresponding to 10% of the substrate. At 86 days after emergence of seedlings the plant growth in height and principal root length, diameter of stem and root, leaf number and dry mass of roots and shoots of plants were evaluated. The salinity of irrigation water increased the salinity levels in the substrate inhibiting the growth in height, stem diameter, leaf emission by plants, diameter and length of principal root and the dry matter production of roots and aerial parts (leaves + stem) of neem, but with less pronounced decrease in plants under the treatments with bovine biofertilizer.

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This paper summarizes floristic and phytossociology data of 11, out of 14 plots of 1 ha, allocated along an altitudinal gradient in the Serra do Mar, Silo Paulo, Brazil. The study was conducted at Serra do Mar State Park and the plots start at the sea level (10 m - plot of Restinga Forest that occurs at Praia da Fazenda, Picinguaba, municipality of Ubatuba) up to 1100 m above sea level (the Montane Ombrophilous Dense occurs alongside the Itamambuca Trail, municipality of Silo Luis do Paraitinga). The Restinga Forest occurs in Pleistocenic Coastal Plain where the soil is classified as a sandy Quartzipsamment (Quartzenic Neosol), while along the slopes of the Serra do Mar, the Ombrophylus Dense Forest grows on the top of a pre-Cambrian crystalline basement with granitic rocks, where the soil is a sandy-loam Dystrophic Inceptisol (Cambisol/Latosol). In all 14 plots soils are acidic (pH 3 - 4), chemically poor, with high dilution of nutrients and high saturation of aluminum. In the Restinga and at the foot of the slope the climate is Tropical/Subtropical Humid (Af/Cfa), with no dry season, an average annual rainfall over 2,200 mm and an average annual temperature of 22 degrees C. Towards the top of the Serra do Mar there is a gradual cooling along the slope, but there is no reduction in rainfall, so at 1,100 m above sea level the climate is classified as Humid Subtropical (Cfa/Cfb), with no dry season and an average annual temperature of 17 degrees C. It is important to remark that, almost daily, from 400 m above sea level up to the top of slopes the mountains are covered by a dense fog. In the 14 plots 21,733 individuals with DBH >= 4.8 cm, including trees, palms and ferns, were marked, measured and sampled. The average number of individuals sampled in each plot was 1264 ind.ha(-1)(+/- 218 SE 95%). Within the parameters considered trees prevailed (71% in the Montane ODF to 90% in the Restinga Forest), followed by palms (10% in the RF and 25% in the Montane Ombrophilous Dense Forest/ODF) and ferns (0% % in the RF and 4% in the Montane ODF). Regarding these proportions the Exploited Lowlands ODF differs from the others with only 1.8% of palm trees and striking 10% of ferns. The forest canopy is irregular with heights ranging from 7 to 9 m, rarely emergent trees reach 18 m, and due to this irregularity of the canopy the amount of light that gets through sets conditions for the development of hundreds of epiphytic species. Aside from Montana ODF, where the number of dead trees was more than 5% of individuals sampled, in the other phytophysiognomies this value was below 2.5%. In the 11 plots where the floristic study was conducted we found 562 species in 195 genera and 68 families. Only seven species - Euterpe edulis Mart. (Arecaceae), Calyptranthes lucida Mart. ex DC. and Marlierea tomentosa Cambess (both Myrtaceae), Guapira opposita (Veil.) Reitz (Nyctaginaceae), Cupania oblongifolia Mart. (Sapindaceae), Cecropia glaziovii Snethl. and Coussapoa microcarpa (Schott) Rizzini (both Urticaceae) - occurred from Restinga to Montane ODF, while 12 other species did not occur only in the Restinga Forest. Families with the greatest number of species are Myrtaceae (133 spp), Fabaceae (47 spp), Rubiaceae (49) and Lauraceae (49) throughout the gradient and Monimiaceae (21) specifically in portions Montane ODF. Only in the F plot, where logging has occurred between 1950 and 1985, the abundance of palm trees has been replaced by Cyatheaceae. The study shows a peak of diversity and richness, Shannon-Weiner index (H') ranging from 3.96 to 4.48 nats.ind(-1), in the intermediate altitudes (300 to 400 m) along the slope. Several explanations for this result are raised here, including the fact that these elevations are within the limits expansions and retractions of the different phytophysiognomies of the Atlantic ODF due to climate fluctuations during the Pleistocene. The results presented in this paper demonstrate the extraordinary richness of tree species of the Atlantic Rainforest from the northeastern coast of the State of São Paulo, reinforcing the importance of its conservation throughout the altitudinal gradient. The richness of this forest justifies a long term commitment to study its dynamics and functioning through permanent plots, and monitor the impacts of climate change in this vegetation.

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Foram estudadas as comunidades de ácaros em indivíduos de Hymenaea martiana Hayne (Leguminosae) com diferentes tamanhos, localizados em fragmento de Mata Estacional Semidecidual com transição para o Cerrado. As plantas analisadas foram selecionadas com base no gradiente de altura e perímetro do tronco a 10 cm acima do solo. Foram realizadas coletas quinzenais no período de março de 2007 a março de 2008. em cada amostragem foram retiradas três folhas dos ramos externos e três dos ramos internos, ao redor da região mediana da copa de cada planta selecionada. Para comparar os padrões ecológicos das comunidades de ácaros entre as plantas, foram aplicados índices descritores da diversidade. em H. martiana, foram registrados 109.445 ácaros pertencentes a 28 espécies de 14 famílias. Nove espécies de ácaros, dentre as 19 classificadas como frequentes e acessórias, tiveram sua densidade populacional influenciada pelo tamanho da planta. Enquanto a densidade populacional de Chiapacheylus edentatus de Leon, 1962, Euseius cf. errabundus, Pronematus sp., Brevipalpus phoenicis (Geijskes, 1939) e Tarsonemus sp., apresentou correlação positiva com a altura da planta, a de Aberoptus aff. cerostructor, Euseius sibelius (De Leon, 1962), Typhlodromalus aripo de Leon, 1967 e Phytoseius nahuatlensis de Leon, 1959, apresentou correlação negativa. Não houve influência da altura da planta sobre a riqueza de espécies e densidade total de ácaros entre ramos internos e externos das plantas com diferentes alturas. As variações fisiológicas entre os indivíduos de diferentes estágios ontogenéticos de H. martiana, juntamente com fatores abióticos, podem ter influenciado a ocorrência e a distribuição dessas espécies de ácaros sobre essa planta.

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A escolha das sementes é de fundamental importância para a obtenção de mudas de qualidade, principalmente quando são produzidas sob condições ambientais adversas. Este trabalho foi desenvolvido com o objetivo de avaliar a influencia da salinidade sobre o desenvolvimento de mudas de moringa provenientes de sementes localizadas em diferentes posições no fruto. O delineamento utilizado foi o inteiramente casualizado, com os tratamentos arranjados em esquema fatorial 3 x 4 e quatro repetições. Os tratamentos resultaram da combinação de três posições de sementes no fruto (basal, mediana e apical) com quatro níveis de salinidade da água de irrigação (0,5; 2,0; 3,5; e 5,0 dS m-1). Foram avaliadas as seguintes características de crescimento: altura (ALT), diâmetro do caule (DC), diâmetro da raiz principal (DRP), número de folhas (NF), área foliar (AF), massa seca da parte aérea (MSPA), massa seca do sistema radicular (MSR) e massa seca total (MST). Os dados foram submetidos à análise de variância pelo teste F e as médias, comparadas pelo teste de Tukey a 5% de probabilidade, para o efeito da posição da semente no fruto; e por análise de regressão, para os dados provenientes da salinidade. Houve interação significativa na maioria das características avaliadas. A salinidade da água de irrigação diminuiu em todas as variáveis. As mudas provenientes de sementes localizadas na porção basal dos frutos foram mais afetadas pela salinidade da água de irrigação.

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Uma das aplicações das técnicas da cultura de tecidos no melhoramento é a identificação de linhas de células que apresentam tolerância à salinidade. Vários autores obtiveram linhas de células tolerantes ao estresse salino; e estudo de mecanismos bioquímicos da tolerância a sais em plantas tem demonstrado altas correlações entre estes e o acúmulo de macromoléculas em tecido de plantas superiores. Para verificar essas correlações em feijão (Phaseolus vulgaris cv IAC carioca), calos oriundos de eixos embrionários foram cultivados em meio sólido, suplementado com NaCl nas concentrações de 0 a 60 mM. Após 13 dias de incubação, os calos foram coletados e analisados quanto ao crescimento relativo, teor de proteínas, teor de prolina e atividade da peroxidase. Os parâmetros analisados mostraram decréscimo no crescimento relativo e no de proteínas em resposta ao NaCl. Paralelamente, observou-se aumento significativo no conteúdo de prolina e atividade da enzima peroxidase.

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Alterações nos níveis de prolina e na atividade da peroxidase foram estudadas em folhas e raízes de feijoeiro em função da resposta à salinidade do meio. A atividade da peroxidase (E.C. 1.11.1.7) e o teor de prolina das folhas foi maior do que nas raízes. Os resultados mostraram que a atividade da peroxidase diminuiu, enquanto os teores de prolina aumentaram gradualmente nas plantas cultivadas em meio salino. Ocorreu diminuição do teor de potássio e aumento de sódio nos órgãos analisados, com o aumento da concentração salina.

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Os efeitos da salinidade sobre a atividade de peroxidases foram acompanhadas no embrião e em cotilédones de feijoeiro Phaseolus vulgaris L. cv. Carioca, observando-se em ambos, aumento na atividade das enzimas. Com relação ao teor de prolina, ocorreu decréscimo constante no embrião de feijoeiro cultivado em condições salinas, entretanto, nos cotilédones, verificou-se aumento progressivo em condições de presença ou ausência de salinidade.

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The objectives of this work were to characterize pineapple plants (Ananas comosus L. Merril) cv. Smooth Cayenne, cultured in vitro, in saline medium, in relation to bromelian activity, identifying the parts of the plant with the highest bromelian activity. Also under aim was the study of the influence of saline stress on the enzyme activity. Axillary buds of pineapple were cultivated in vitro in MS medium, supplemented with 2 mg.L-1 BAP and 1 mg.L-1 NAA. The levels of salinity tested were: 0.57 g.L-1 NaCl, 1.15 g.L-1 NaCl, and 2.30 g.L-1 NaCl. Bromelian activity was evaluated in the development of buds, shoots, and roots. The results showed that bromelian activity was higher in buds at the highest salt concentration at 15 days. Cultured shoots showed bromelian activity decreasing in the saline treatments in all the collection, up to 60 days in culture. The roots showed higher bromelian activity in the roots in saline medium.

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The objective of this work is to analyze the effects of salinity and wastewater on the zooplankton community of the Itanhaém river estuary, São Paulo state. Samples of zooplankton as well as physical and chemical variables of water were collected in four sites, located between the coastal line and the superior part of the estuary, including a secondary channel where wastewater is thrown without previous treatment. The samples were collected in low and high tide in winter and summer. Results showed that the estuary presents a temporal and spatial variation of physical and chemical characteristics, especially salinity, in function of the tide and seasonal variation of rain. The high values of salinity occurred in winter and high tide. Zooplankton community was adapted to the dynamic of salinity, and marine and estuarine species occurred in the low part of the estuary in winter. Although the Itanhaém river estuary has the same temporal and spatial dynamic of other estuaries, the values of salinity are low when compared with others located in the southern coast of São Paulo. Consequently, mainly oligohaline and fresh water species constitute the zooplankton community. These characteristics are due to the great drainage area of the Itanhaém river basin. The waste water modified physical and chemical characteristics of water that now presents higher concentrations of nutrients, higher values of suspended matter and lower concentrations of oxygen. It was observed a positive relation between the density of nauplii of copepods and organic pollution in this estuary.

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The agricultural unpaved roads are important road structures for the economic and social agricultural development of the Nation, and the erosion provoked by rain water in the road bed and sides are closely related to bad draining, one of the main factors for their degradation. In order to make the draining system adequate, it is necessary to know about erodibility, infiltration capacity of water in the ground and adoption of mechanical slope abatement with grid elevation and water interception. This study presents drainage model through the construction of terraces with gradient transversally associated to the capitation basin in abruptic red dystrophic argisol soils, medium sandy texture, based on slops abatement techniques, elevating the road bed and deviating flow. The grain sized fractions of this ground (sand, silt, clay) and the aggregate stability indicated that this ground, under anthropic action, presents erosive processes resulting in superficial draining with ground hauling, sanding sources and courses of water situation below roads, providing great environmental impacts in the hydric bodies. The reduction of erosion problems in these unpaved roads is in the adoption of measures that intercept waters from the draining of their stream bed itself, as well as pluvial waters comings from adjacent areas of contribution, that are collected and conducted to inlaid terraces and capitation basis.