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Registros recuperados: 360 | |
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Ramos,Márcio V.; Araújo,Eliane S.; Oliveira,Raquel S. B.; Teixeira,Fabiano M.; Pereira,Danielle A.; Cavalheiro,Mariana G.; Souza,Diego P.; Oliveira,Jefferson S.; Freitas,Cleverson D. T. de. |
Latex is an endogenous milky fluid synthesized and accumulated under pressure in a network of laticifer cells. In this study, latices from five plant species were examined for deterrent effect on oviposition of two Coleoptera (Bruchidae) pests. The latex from Euphorbia tirucalli, Calotropis procera and Plumeria rubrae exhibited deterrent activity on oviposition of both Callosobruchus maculatusand Zabrotis subfasciatus beetles. The latex from Cryptostegia grandiflora and Himathantus drasticus were less effective to C. maculatus and Z. subfasciatus oviposition, respectively. Eggs laid on latex-treated seeds were not affected.The emergence and the mean time of development and weight of larvae grown in treated seeds were similar to the controls. The deterrent... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Calotropis procera; Deterrent activity; Insect; Laticifers; Proteins; Plumeria rubra. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202011000100008 |
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Eira,Mirian T. S.; Silva,E. A. Amaral da; De Castro,Renato D.; Dussert,Stéphane; Walters,Christina; Bewley,J. Derek; Hilhorst,Henk W. M.. |
Considerable advances in our understanding of coffee seed physiology have been made in recent years. However, despite intense research efforts, there are many aspects that remain unclear. This paper gives an overview of the current understanding of the more important features concerning coffee seed physiology, and provides information on recent findings on seed development, germination, storage and longevity. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coffea; Coffee; Germination; Germplasm; Longevity; Seed development; Storage. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000100011 |
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Domingues,Sarah J.S.; Souza,Thiago F. de; Soares,Alexandra M.S.; Jacinto,Tânia; Machado,Olga L.T.. |
In order to investigate the defense response in castor bean (Ricinus communis) against predators, we analyzed the effect of mechanical wounding upon the phospholipase A2 (PLA2) activity of leaf extracts. Time course experiments revealed that the highest levels of increased PLA2 activity (ca. two fold) occurred 15 min and 60 min after injury. The induced activities demonstrated high sensitivity towards aristolochic acid (10 mM), a PLA2 inhibitor. Based on SDS-PAGE analysis, the PLA2 activity induced 15 min after wounding migrated with a molecular mass of 40 kDa and was denoted RcPLA2 I. The protein activity induced 60 min after wounding, RcPLA2 II, migrated with a molecular weight of 14 kDa. Furthermore its N-terminal sequence shared homology with PLA2 from... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cellular defense; Castor bean; Plant signaling; Phospholipase A2; Ricinus communis. |
Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202007000100004 |
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Antoniolli,Lucimara R.; Benedetti,Benedito C.; Sigrist,José M.M.; Souza Filho,Men de Sá M.; Alves,Ricardo E.. |
The effects of cut shape and temperature on the respiratory activity and ethylene synthesis of fresh-cut 'Pérola' pineapple were investigated. Two experiments were carried out. In the first, slices and chunks were placed in air-tight packages kept at 4 or 10ºC. Gas samples were taken every 2 h during 12 h and analysed by gas chromatography. In the second experiment, peeled fruits, slices and chunks were placed in air-tight glass jars connected to a flowboard installed in a cold room at 5 ± 1ºC. This system provided a continuous flow of humid and cold air during 14 d. Respiration rate was determined every 2 h, during the first 12 h, then daily for 10 d and on days 12 and 14. Ethylene synthesis was not detected during 12 h of evaluation. The lower... |
Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Ananas comosus; Ethylene; Minimal processing; Respiration rate. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000300008 |
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Campos,Ângela Diniz; Ferreira,Alfredo Gui; Hampe,Magdolna Maria Vozári; Antunes,Irajá Ferreira; Brancão,Nely; Silveira,Expedito P.; Silva,João Batista da; Osório,Vera Algayer. |
The activities of the enzymes chalcone synthase (CHS) and phenylalanine ammonia-lyase (PAL) were measured in leaf extracts obtained from four cultivars of the common bean (AB 136, Rio Tibagi, Carioca and Macanudo). Two stages of plant development were examined: plantlets (V2) and the onset of blooming (R6). Initially, the plants were either treated with salicylic acid or inoculated with the delta race of Colletotrichum lindemuthianum (inductive fungus) and after three days they were evaluated for enzyme activity. Afterwards, all plants were inoculated (challenged) with the virulent pathotype 33/95 of C. lindemuthianum except for the water control. Five days later, the activities of PAL and CHS were evaluated. There were significant changes in the... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Anthracnose; Phaseolus vulgaris; Systemic acquired resistance. |
Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202003000300001 |
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Gonçalves,Jamile F.; Becker,Alexssandro G.; Pereira,Luciane B.; Rocha,João B. T. da; Cargnelutti,Denise; Tabaldi,Luciane A.; Battisti,Vanessa; Farias,Júlia G.; Fiorenza,Amanda M.; Flores,Érico M. M.; Nicoloso,Fernando T.; Schetinger,Maria R. C.. |
In this study, the effects of lead (Pb) on growth, photosynthetic pigments concentration, lipid peroxidation, electrolyte leakage percentage (ELP), protein oxidation, aminolevulinate dehydratase (ALA-D; E.C. 4.2.1.24), 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 (AsA), non-protein thiol groups (NPSH) and total soluble protein concentrations in cucumber seedlings (Cucumis sativus L.) were investigated. Seedlings were grown in vitro in an agar-solidified substrate containing three Pb levels as (C2H3O2)Pb.3H2O (0, 100, 400, and 1000 µmol L-1) for 10 d. Increasing Pb concentrations in substrate enhanced Pb concentration in both roots and shoot. Pb... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Antioxidant enzymes; Cucumber; Lipid peroxidation; Pb; Photosynthetic pigments; Protein oxidation. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202009000300002 |
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Panda,S.K.; Choudhury,S.. |
The article presents an overview of the mechanism of chromium stress in plants. Chromium is known to be a toxic metal that can cause severe damage to plants and animals. Chromium-induced oxidative stress involves induction of lipid peroxidation in plants that causes severe damage to cell membranes. Oxidative stress induced by chromium initiates the degradation of photosynthetic pigments causing decline in growth. High chromium concentration can disturb the chloroplast ultrastructure thereby disturbing the photosynthetic process. Like copper and iron, chromium is also a redox metal and its redox behaviour exceeds that of other metals like Co, Fe, Zn, Ni, etc. The redox behaviour can thus be attributed to the direct involvement of chromium in inducing... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Antioxidants; Chromium; Fenton reactions; Metallothioneins; Oxidative stress. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000100008 |
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Adamczyk,Bartosz; Godlewski,Mirosław. |
It is now well-known that plants can uptake not only inorganic nitrogen but also organic nitrogen compounds, mainly amino acids. However, soil proteins are the main pool of amino acids. According to our earlier papers, plants can get access to this source of nitrogen using root-secreted proteases, but the level of proteolytic activity of such root-secreted proteases is species-specific. Our aim was to compare the use of protein as nitrogen source by two vegetable crops having high (Allium porrum) or low (Lactuca sativa) level of activity of root-secreted proteases. Seedlings were cultivated on Murashige and Skoog medium (MS), MS medium without inorganic nitrogen, MS medium without inorganic nitrogen, but with casein in concentration of 0.01%, 0.1% or 1%.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Organic nitrogen; Plant nitrogen nutrition; Secretion of proteases. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202010000300004 |
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Silva,José Vieira; Lacerda,Claudivan Feitosa de; Costa,Paulo Henrique Alves da; Enéas Filho,Joaquim; Gomes Filho,Enéas; Prisco,José Tarquínio. |
Pitiuba cowpea (Vigna unguiculata (L.) Walp.) plants were grown in nutrient solution and kept in a greenhouse up to pre-flowering stage. They were subjected to four different treatments: nutrient solution; nutrient solution containing 75 mmol.L-1 NaCl; nutrient solution containing 75 mmol.L-1 NaCl and 5 mmol.L-1 CaCl2; and nutrient solution containing 75 mmol.L-1 NaCl and 10 mmol.L-1 CaCl2. Salt stress strongly inhibited plant growth, caused a disturbance in plant-water balance, and increased the total content of inorganic solutes in the different plant parts, due mainly to accumulation of Na+ and Cl-. It also increased leaf and root soluble carbohydrates, reduced soluble amino nitrogen both in root tips and in the youngest trifoliate leaves, and reduced... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Calcium; Growth; Salt stress; Solutes accumulation; Vigna unguiculata; Water relations. |
Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202003000200005 |
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Vestena,Silvane; Cambraia,Jose; Ribeiro,Cleberson; Oliveira,Juraci A.; Oliva,Marco A.. |
The reactive oxygen species generation, lipid peroxidation and antioxidative enzyme response of water hyacinth and salvinia to Cd were evaluated. Cadmium was absorbed/accumulated mainly in the roots, but significant amounts also translocated to the leaves. No Cd effect on dry weight was detected, although toxicity symptoms were visible. Superoxide and H2O2 concentrations increased, in addition to lipid peroxidation in both species, especially in the leaves of salvinia. In general, antioxidative enzyme activities were reduced in both species following Cd treatment, especially in salvinia. Glutathione peroxidase (GPX, EC 1.11.1.9) activity decreased in water hyacinth but increased in salvinia. Glutathione S-transferase (GST, EC 2.5.1.18) activity increased... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Aquatic plants; Eichhornia crassipes; Metal toxicity; Oxidative stress; Salvinia auriculata. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202011000200005 |
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Ashihara,Hiroshi. |
Coffee beans contain two types of alkaloids, caffeine and trigonelline, as major components. This review describes the distribution and metabolism of these compounds. Caffeine is synthesised from xanthosine derived from purine nucleotides. The major biosynthetic route is xanthosine -> 7-methylxanthosine -> 7-methylxanthine -> theobromine -> caffeine. Degradation activity of caffeine in coffee plants is very low, but catabolism of theophylline is always present. Theophylline is converted to xanthine, and then enters the conventional purine degradation pathway. A recent development in caffeine research is the successful cloning of genes of N-methyltransferases and characterization of recombinant proteins of these genes. Possible biotechnological... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coffea; Caffeine; Purine alkaloids; Pyridine alkaloids; Theobromine; Trigonelline. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202006000100001 |
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Pereira,Luiz Filipe Protasio; Galvão,Rafaelo M.; Kobayashi,Adilson K.; Cação,Sandra Maria B.; Vieira,Luiz Gonzaga Esteves. |
The phytohormone ethylene is involved in several physiological and developmental processes in higher plants, including ripening of fruits, abscission of organs and tissues, senescence, wound response as well as in other abiotic stresses. The enzyme 1-aminocyclopropane-1-carboxylate oxidase (ACO) catalyzes the last step of ethylene biosynthesis. The production of ethylene and the expression of a Coffea arabica ACO gene during the last stages of fruit maturation were investigated. A rapid increase of ethylene production at the green-yellow stage of fruit ripening, after the end of endosperm formation, and a decrease of ethylene production at the cherry stage indicates a climacteric phase during ripening. An ACC oxidase (Ca-ACO) from coffee fruit cDNA was... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: ACC oxidase; Climacteric; Coffee; Ethylene; Maturation. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202005000300002 |
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Medeiros,David Barbosa; Silva,Elizamar Ciriaco da; Santos,Hugo Rafael Bentzen; Pacheco,Cinthya Mirella; Musser,Rosimar dos Santos; Nogueira,Rejane Jurema Mansur Custódio. |
To evaluate physiological genotypic differences between two Barbados cherry genotypes (13- and 14-CPA) under water deficit, initial growth, water relations, and organic solute accumulation were evaluated in an experiment performed using four-month-old seedlings, which were subjected to four water treatments (100, 75, 50, and 25% of field capacity), with five replications. Severe water deficit (25% of field capacity) negatively affected plant height, stem diameter, leaf area, dry matter of the leaves and stem to both genotypes, and root dry matter to genotype 13-CPA. Predawn (Ywpd) and midday leaf water potentials (Ywmd) were reduced in plants grown under 25% of field capacity, only in the genotype 14-CPA. There was not a change in relative water content,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Malpighia emarginata DC; Soluble organic solutes; Biomass allocation; Water relations; Water deficit. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202012000300005 |
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Choudhary,Sikander P.; Bhardwaj,Renu; Gupta,Bishan D.; Dutt,Prabhu; Kanwar,Mukesh; Arora,Priya. |
The effects of various conc of (10-11, 10-9 and 10-7 M) 24-epibrassinolide (24-epiBL) on polyamines and auxins contents was analyzed in 7days old seedlings of Raphanus sativus L. cv. Pusa chetki under copper metal stress. Cu metal (0.2mM) treatment significantly increased endogenous levels of putrescine, spermidine and spermine when compared with control values. Cadaverine content got decreased under metal stress. Endogenous polyamines showed varying levels in seedlings when applying 24-epiBL treatment only. Maximum increase was found in putrescine, cadaverine and spermidine in 10-11, 10-9 and 10-7 M conc of 24-epiBL respectively when applied alone to R. sativus seedlings. However, metal treatment supplemented with 24-epiBL revealed small increase in... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Raphanus sativus; Polyamines; Auxins; Brassinosteriods; Oxidative stress; Heavy metal stress. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202009000100004 |
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Registros recuperados: 360 | |
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