|
|
|
| Registros recuperados: 360 | |
|
|
| Lage-Pinto,Frederico; Bernini,Elaine; Oliveira,Jurandi Gonçalves de; Vitória,Angela Pierre. |
| Gas exchange, chlorophyll afluorescence, and photosynthetic pigments of Xylopia sericeaA. St.-Hil. and Siparuna guianensis Aubl. were evaluated during the rainy season and the dry season (2009-2010) in three understories with different ecological conditions (irradiance, water availability, and temperature) located in the União Biological Reserve (known as REBIO União), at Rio de Janeiro State, a natural forest understory, eucalyptus understory under regeneration, and understory of eucalyptus plantation with 18-year-old trees that were removed 1 year before. The lowest values of Fv/Fm e Fm/Fo were observed in the exposed understory for both seasons, with lower values in the dry season, suggesting that reduced water availability potentializes the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Corymbia citriodora; Dehydration; Photoinhibition; Siparuna guianensis; Xylopia sericea. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000200003 |
| |
|
| |
|
|
| Gonçalves,Jamile F.; Becker,Alexssandro G.; Cargnelutti,Denise; Tabaldi,Luciane A.; Pereira,Luciane B.; Battisti,Vanessa; Spanevello,Rosélia M.; Morsch,Vera M.; Nicoloso,Fernando T.; Schetinger,Maria R.C.. |
| In this study, the effects of cadmium (Cd) on lipid peroxidation, electrolyte leakage, protein oxidation, ascorbate peroxidase (APX; E.C. 1.11.1.11), catalase (CAT; E.C. 1.11.1.6) and superoxide dismutase (SOD; E.C. 1.15.1.1) activities, and ascorbic acid, non-protein thiol groups and total soluble protein contents in cucumber seedlings (Cucumis sativus L.) were investigated. Seedlings were grown in vitro in an agar-solidified substrate containing four Cd levels as CdCl2 (0, 100, 400, and 1000 µmol L-1) for 10 d. The lowest Cd level decreased the malondialdehyde concentration. Electrolyte leakage increased only at 1000 µmol Cd L-1, whereas protein oxidation and total soluble protein content were enhanced at 400 and 1000 µmol Cd L-1. Activity of APX was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Antioxidant enzymes; Ascorbic acid; Cucumis sativus; Heavy metal; Lipid peroxidation; Protein oxidation. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000300006 |
| |
|
|
| Verma,Aman; Malik,Chander Parkash; Gupta,Vijay Kumar; Bajaj,Bhavneet Kaur. |
| In vitro effects of triacontanol (TRIA) on antioxidant enzymes and photosynthetic characteristics were studied in Arachis hypogaea L. cultivars (M-13 and PBS24030). The in vitro impact of TRIA on multiplication potential was also evaluated, which was found to be best at 2.0 ml L-1 TRIA in combination with 6- Benzyl adenine (BA, 3 mg L-1) in both the groundnut cultivars. Rhizogenesis was observed in almost all the TRIA treated cultures in both the cultivars. Moreover, shoots failed to set roots, in the presence of BA. Total chlorophyll content, total soluble sugars, total soluble proteins and ascorbate peroxidase (APX; EC 1.11.1.11) activity were found to be increasing with increasing concentrations of TRIA, whether alone or in combination with BA, however,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Catalase; Groundnut; Peroxidase; Vipul. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202011000400004 |
| |
|
|
| Garbin,Mário L.; Dillenburg,Lúcia R.. |
| The southern Brazilian highland plateau is a mosaic of two contrasting plant communities, Araucaria forests and grasslands, which differ in the relative abundances and spatial patterns of soil nitrate and ammonium. However, we still do not know the inorganic N preferences of one key species in this mosaic, Araucaria angustifolia, the dominant tree species in the Araucaria forests and an important tree species invading the adjacent grasslands. Growth responses measured in a greenhouse study demonstrated that the species prefers NH4+ over NO3- as an inorganic N source. When provided alone, NO3- induced N deficiency symptoms: increases in root: shoot ratio, root branching and leaf mass per area, thickening of the shoot apexes and decreased mass-based... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Araucariaceae; Ammonium; Inorganic nitrogen; Nitrate; Nitrogen deficiency. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202008000400005 |
| |
|
|
| Souza,Gustavo M.; Ribeiro,Rafael V.; Pincus,Steven M.. |
| Stomatal aperture is an essential factor both in regulation of transpiration and net photosynthesis. This regulation is especially important in the response of plants to drought or to an increase in leaf-to-air vapor pressure difference (VPD); however, such a regulation is part of a complex dynamical environment, associated with multiple regulatory pathways. Accordingly, we studied the effects of VPD on gas exchange of Citrus sinensis via the evaluation of two complementary analytic approaches, to approach an understanding of the full scope of the system interactions. First, we used classical statistical methodologies, e.g., means, coefficient of variation, and linear correlation. Second, we used measures developed for more model-independent applications,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Approximate entropy; Leaf-to-air vapor pressure difference; Network modulation; Time-series analysis. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202004000300001 |
| |
|
|
| Hameed,Asiya; Qadri,Tabasum N.; Mahmooduzzafar,; Siddiqi,T.O.; Iqbal,M.. |
| Cadmium and Mercury induced varying responses in Abelmoschus esculentus L. in relation to enzymes (ascorbate peroxidase (APX, 1.11.1.11), catalase (CAT, 1.11.1.6), glutathione reductase (GR, 1.6.4.2) and superoxide dismutase (SOD, 1.15.1.1) which are most related to the levels of Hg and Cd applied and concentrations of thiol groups already present or induced upon treatment. In the present investigation varying concentrations of CdCl2 and HgCl2 (0, 0.05, 0.10, 0.50, 1 and 2mM respectively) applied to plant in the soil shows a significant increase in ascorbate peroxidase, glutathione reductase and superoxide dismutase activities, and the respective metal accumulation. It reveals a mechanism for constant detoxification of H2O2 that have to be associated with... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Antioxidative enzymes; Metals detoxification; Reactive oxygen species. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202011000100007 |
| |
|
|
| Lima,Consuelo M. R. de; Zanotta,Pedro J. P.; Ricart,Carlos A. O.; Sousa,Marcelo V. de. |
| Enterolobin is a 52.9 kDa, cytolytic, inflammatory and insecticidal protein present in Enterolobium contortisiliquum (Vell.) Morong, a Brazilian large-sized tree. This protein was previously described to occur in different forms of association (monomeric and oligomeric forms). In the current work, we investigated the presence of enterolobin forms of association and hemolytic activity in maturing, germinating and germinated seeds. Immunoblotting analysis revealed the presence of the monomeric form of enterolobin in all phases under study, whereas the dimer was detected in developing seeds in the second half of the maturation period, during germination and in the early post-germination phase. The trimeric form of enterolobin appeared one week after the dimer... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Defense proteins; Hemolytic proteins; Plant defense; Seed germination. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000200008 |
| |
|
|
| Salomão,Antonieta Nassif. |
| The ability to tolerate ultra-low temperature (-196 ºC) exposure was evaluated in 66 tropical orthodox seed species of 21 botanical families from the Cerrado (Brazilian Savannah) and Atlantic Forest Brazilian biomes. Liquid nitrogen had no effect on the germinability of 51 seed species. The stimulatory effect of cryogenic temperature on germinability, with or without subsequent chemical scarification, was observed in nine seed species with deep physical dormancy, or heterogeneous levels of seed hardness, or with no dormancy. Significant reduction in germinability occurred in six seed species, presumably because of factors acting individually or in combination on these seeds, such as inappropriate moisture content, or the potentially detrimental effect of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cryopreservation; Ex situ conservation; Seed dormancy. |
| Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000200008 |
| |
|
|
| Ambede,Jane Gayalwa; Netondo,Godffrey Wafula; Mwai,Gideon Njau; Musyimi,David Mutisya. |
| The effects of NaCl salinity on seed germination, growth, physiology, and biochemistry of two bambara groundnut landraces (Vigna subterranea (L.) Verdc), Kakamega (white seed coat) and Mumias (red seed coat), were investigated with the aim of establishing traits, which can provide a basis for breeding to salt tolerance in groundnuts. A study was conducted under laboratorial and greenhouse conditions. Bambara groundnut seeds and plants were subjected to five concentrations of NaCl solutions with several electrical conductivities: 0 (control), 6.96, 12.93, 19.89, and 25.86 dS m-1. Germination percentage, growth, chlorophyll fluorescence, and leaf chlorophyll content were determined. Sodium chloride salinity (p<0.05) significantly decreased germination and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Salinity; Vigna subterranea; Growth physiology; Saline water. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000300002 |
| |
|
| |
|
| |
|
|
| Santos,Mauro Guida dos; Ribeiro,Rafael Vasconcelos; Oliveira,Ricardo Ferraz de; Pimentel,Carlos. |
| This study was conducted to evaluate the effect of foliar Pi application on gas exchange and yield of bean genotypes submitted to a mild water deficit at the pre-flowering stage. In the first experiment, when extra Pi (10 g.L-1) was sprayed on leaves during water stress or during recovery, there was no effect on gas exchange or yield in the A320, Carioca and Ouro Negro genotypes. However, net CO2 assimilation (A) of A320 and Ouro Negro was less affected, but not significantly, than Carioca at the end of the stress, when Pi was supplied five days before water deficit. In the second experiment, two different doses of Pi (10 and 20 g.Pi L-1) were sprayed five days before water deficit on the Carioca genotype. During the last three days of the mild water... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Common bean; Inorganic phosphorus; Photosynthesis; Water deficit. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202004000300007 |
| |
|
| |
|
|
| Pinheiro,Hugo Alves; Borges,Regis; Silva,Marco Aurélio Pedron e; Centeno,Danilo Cruz. |
| Potato tubers (Solanum tuberosum L. cv. Binje) were stored at 18 and 4ºC in order to verify changes in mitochondrial metabolism, especially in the activities of the alternative oxidase (AOX) and plant uncoupling mitochondria protein (PUMP). Tubers were also sliced and submitted to artificial aging. The oxygen consumption rate (OCR), respiratory control (RC) and ADP/O ratio for mitochondria obtained after storage at 18ºC were not altered, regardless of the time of storage. Considerable increment in OCR, for both respiratory states 3 and 4, was observed after storing the tubers for five and ten days at 4ºC; and it was accomplished by reductions in RC and ADP/O. The AOX activity was evident after five days at 4ºC, and it was enhanced after ten days of storage... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Solanum tuberosum L.; Mitochondrial swelling; Oxidative stress; Respiration. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202004000200001 |
| |
|
|
| Vitória,Angela P.; Lage-Pinto,Frederico; Campaneli,Leonardo B.; Almeida,Marcelo G.; Souza,Cristina M. M.; Rezende,Carlos E.; Azevedo,Ricardo A.; Oliveira,Jurandi G.. |
| The ecophysiological adaptations of water hyacinth (metal hyperaccumulator) under adverse environmental conditions are not yet clearly elucidated. This work evaluated photosynthetic pigments and chlorophyll a fluorescence in water hyacinth plants sampled in different regions (upper, middle and lower) of Paraíba do Sul river (PSR) and Imbé river, Brazil. Additionally Mn, Fe, Zn, Cu, Cr, Pb and Ni were quantified on the shoots and roots. Roots were the preferential site of metal accumulation. Cromium was not detected in the shoots. Iron and Mn were the elements detected in higher concentrations in all samples. Zinc and Cu were detected in higher concentrations in roots of plants from middle and upper PSR, sites of higher anthropogenic activity. The highest... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pollution; Paraíba do Sul river; Energy dissipation; Photosynthetic pigments; Nonphotochemical quenchings. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202010000100006 |
| |
|
|
| Sridhar,Balaji B. Maruthi; Han,Fengxiang X.; Diehl,Susan V.; Monts,David L.; Su,Yi. |
| Structural and ultrastructural changes caused by bioaccumulation of As and Cr in brake fern (Pteris vittata), a known arsenic hyperaccumulator, were investigated. Potted plants of brake fern were exposed to metal treatments of As and Cr for three weeks. Leaf, stem and root samples were collected periodically and fixed for LM (Light Microscopy), SEM (Scanning Electron Microscopy) and TEM (Transmission Electron Microscopy) to evaluate anatomical changes. The fresh weights, dry weights, RWC (Relative Water Content) and plant heights were obtained before the brake fern plants were harvested for metal accumulation analysis. The As accumulated mainly in the shoots while Cr accumulated mainly in the roots of the metal-treated plants. Significant changes in the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Anatomy; Arsenic; Chromium; Hyperaccumulator; Microscopy; Phytoremediation; Pteris vittata; Translocation; Ultrastructure. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202011000400006 |
| |
|
| |
|
| |
|
|
| Rocha,Andréa C.; Canal,Emerson C.; Campostrini,Eliemar; Reis,Fabrício O.; Cuzzuol,Geraldo Rogério F.. |
| Most studies of chromium have been realized in the sediments and in mangrove trees. However, little is known about its effect on growth and metabolism in this vegetation. L. racemosa plants were grown in solution with 20% of ionic strength of Hoagland and Arnon containing 100 mM NaCl and supplemented with 0.00, 0.05 and 0.50 mg L-1 of Cr+3. The growth, the pigments and gas exchange measurements showed no changes in response to doses of chromium. After 30 days the initiation of treatments, plants of L. racemosa had average 0.559 g of total dry weight, 1.34 mg L-1 of total chlorophyll and 7.9 µmol m-2 s-1 of A (CO2 photosynthetic assimilation). The photochemical potential efficiency was affected by the intermediate dose of 0.05 mg L-1 of Cr+3 (Fv/Fm=0.73)... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Carbohydrates; Fluorescence; Gas exchange; Growth; Heavy metal; Mangrove. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202009000200001 |
| |
| Registros recuperados: 360 | |
|
|
|
