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	Provedor de dados Infoteca-e (11) Autor FORMIGA, D. das N. (11) LIGNON, G. B. (10) MARQUES, S. M. T. (6) FREITAS, A. R. de (5) SOBESTIANSKY, J. (3) UENO, H. (2) BRITO, J. R. F. (1) GOMES, P. C. (1) PACHECO, C. R. V. M. (1) Mais... Palavra-chave Swine. (5) Parasites (4) Controle (3) Parasitos (3) Parasitos. (3) Suínos (3) Control. (2) Parasites. (2) Porca. (2) Sow. (2) Suíno. (2) Colistin (1) Colistina (1) Combate. (1) Crescimento (1) Growth (1) Leitão (1) Levamisol (1) Nematode (1) Nematodeos. (1) Mais... Tipo do documento Comunicado Técnico (INFOTECA-E) (7) Outras publicações técnicas (INFOTECA-E) (3) Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) (1) Ano 1981 (2) 1980 (9) País Brazil (11) Idioma Português (11)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 360 Primeira ... 1 2 3 4 5 6 7 8 9 ... Última Tropical seed species' responses to liquid nitrogen exposure Braz. J. Plant Physiol. 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 Brassinosteroid phytohormones: structure, bioactivity and applications Braz. J. Plant Physiol. Zullo,Marco António Teixeira; Adam,Günter. Brassinosteroids are a new class of plant hormones with a polyoxygenated steroid structure showing pronounced plant growth regulatory activity. This review covers their natural occurrence, biological and chromatographic methods for their detection, biosynthesis and metabolism, biological activity, structure-activity relationships and prospective agricultural uses. Tipo: Info:eu-repo/semantics/article Palavras-chave: Brassinolide; Brassinosteroids. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000300001 Brotação do rizoma de Kohleria sp Braz. J. Plant Physiol. Almeida,Julieta Andrea Silva de; Pereira,Maria de Fátima D. A.. O gênero Kohleria sp pertencente à família Gesneriaceae possui órgão subterrâneo. Este órgão é um caule envolto por folhas modificadas, imbricadas, as quais acumulam reservas e cada uma destas protege uma gema. Seções do rizoma brotam sem necessidade do órgão inteiro. Seções deste rizoma com seis folhas modificadas foram colocadas para brotar em placas de Petri e testadas quanto às temperaturas de 15, 20, 25, 30 e 35 ºC, na luz ou no escuro e ainda em relação aos teores de umidade do substrato, onde se adicionaram os volumes de 1, 12 e 20 mL de água destilada. Estes fatores influenciaram a brotação de seções do rizoma de Kohleria sp. As seções também se mostraram resistentes à falta de água, já que, nessa condição, apresentaram brotações e ainda as... Tipo: Info:eu-repo/semantics/article Palavras-chave: Gema; Luz; Temperatura; Tempo de brotação; Teor de umidade. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000100006 Atividade fotossintética e peroxidação de lipídios de membrana em plantas de aroeira-do-sertão sob estresse hídrico e após reidratação Braz. J. Plant Physiol. Queiroz,Cristina G. S.; Garcia,Queila S.; Lemos Filho,José Pires. Avaliaram-se os efeitos do estresse hídrico e da reidratação sobre parâmetros de fluorescência, condutância estomática e peroxidação de lipídios em plantas de Myracrodruon urundeuva Fr. All. (Anacardiaceae). As plantas foram cultivadas em casa de vegetação e a seca foi induzida por suspensão da irrigação durante 14 dias. Sob estresse hídrico, observou-se queda acentuada no conteúdo relativo de água foliar, o qual alcançou valores próximos a 60 %. Essa queda foi acompanhada por grande diminuição na condutância estomática e na taxa aparente de transporte de elétrons (ETR) e extensivos danos às membranas evidenciados por aumentos na peroxidação de lipídios. Apesar do decréscimo nos valores de ETR, não se observaram alterações nos valores do rendimento... Tipo: Info:eu-repo/semantics/article Palavras-chave: Condutância estomática; Estresse oxidativo; Fluorescência; Fotossíntese; Myracrodruon urundeuva. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000100008 Change in root apical protein and peroxidase activity in response to aluminum in tolerant and sensitive maize inbred lines Braz. J. Plant Physiol. Souza,Isabel Regina Prazeres de; Alves,Vera Maria Carvalho; Parentoni,Sidney Netto; Oliveira,Antônio Carlos de; Teixeira,Flávia França; MacAdam,Jennifer Wilson; Purcino,Antônio Álvaro Corsetii. The effects of a short-term (80 min) exposure to 222 µM aluminum (Al) on the protein content and expression and on peroxidase activity and isoenzymes in the primary root of maize were evaluated. Two inbred lines differing in their level of tolerance to Al were used: Cateto 237 (tolerant) and L36 (sensitive). The apical 20 mm of the primary root was divided into 2-mm-long segments that were analyzed for total protein content and peroxidase activity. These results demonstrate that the total protein content along the root apex was not affected by Al in the tolerant inbred line, but decreased in the sensitive line. In the apical 2 mm of the root of the sensitive line, the expression of low molecular weight proteins (43 kDa or smaller) was decreased. Expression... Tipo: Info:eu-repo/semantics/article Palavras-chave: Aluminum toxicity; Maize; Peroxidase isoforms; Root growth. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000300006 Pollen treatment in high osmotic potential: a simple tool for in vitro preservation and manipulation of viability in gametophytic populations Braz. J. Plant Physiol. Loguercio,Leandro Lopes. A method for in vitro preservation and manipulation of pollen viability based on simple changes in osmotic potential (sucrose concentrations) in culture media was developed using tobacco pollen as the experimental model. High osmotic potentials were capable of reversibly inhibiting pollen germination, preserving its viability at room temperature for long periods, as assessed by subsequent incubation in germination medium. When pollen was pre-germinated for different periods and subsequently incubated in 80 % sucrose medium (inhibiting medium) there was a progressive decrease in its viability, which was a trend best described by a quadratic regression line. Nevertheless, very small variations in pollen-tube lengths and viable pollen grains more resistant to... Tipo: Info:eu-repo/semantics/article Palavras-chave: Gametophytic selection; In vitro pollen germination; Nicotiana tabacum; Pollen storage; Pollen viability. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000100009 Positive, negative and marker-free strategies for transgenic plant selection Braz. J. Plant Physiol. Aragão,Francisco José Lima; Brasileiro,Ana Cristina Miranda. In this review, the use of the most common selection marker genes on plant transformation and the effects of their respective selective agents are discussed. These genes could be divided in two categories according their mode of action: genes for positive and negative selection. The retention of the marker gene flow through chloroplast transformation is also discussed. Further, strategies to recover marker-free transgenic plants, involving multi-auto-transformation (MAT), co-transformation, site-specific recombination and intragenomic relocation of transgenes through transposable elements are reviewed. Tipo: Info:eu-repo/semantics/article Palavras-chave: Antibiotic resistance; Herbicide resistance; Marker genes; Plant transformation; Selection; Transgenic plant. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000100001 Efeito da aplicação de zinco via foliar na síntese de triptofano, aminoácidos e proteínas solúveis em mudas de cafeeiro Braz. J. Plant Physiol. Malta,Marcelo Ribeiro; Furtini Neto,Antônio Eduardo; Alves,José Donizeti; Guimarães,Paulo Tácito Gontijo. Avaliou-se, neste trabalho, o efeito da aplicação de Zn via foliar na síntese de triptofano, aminoácidos totais e proteínas solúveis totais em mudas de cafeeiro (Coffea arabica L.). Cultivaram-se as mudas em solução nutritiva sem Zn durante quatro meses e após esse período, pulverizaram-se as plantas com ZnSO4.7H2O a 0,6 %, definindo-se os tratamentos segundo a posição de aplicação (basal: 6 pares de folhas inferiores, ou apical: 6 pares de folhas superiores, além dos ramos plagiotrópicos). As plantas foram coletadas nos tempos: 0 (testemunha), 12, 24, 48 ou 72 h após aplicação de Zn, separando-se as folhas da região apical, basal e dos ramos plagiotrópicos. Determinaram-se as concentrações foliares de triptofano, aminoácidos totais e proteínas solúveis... Tipo: Info:eu-repo/semantics/article Palavras-chave: Coffea arabica; Metabolismo; Proteína; Triptofano. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000100004 Evidence of an endogenous lectin receptor in seeds of the legume Cratylia floribunda Braz. J. Plant Physiol. Ramos,Márcio Viana; Bomfim,Liezelotte Rezende; Bandeira,; Debray,Henri. Cratylia floribunda seeds were ground and the clean crude saline extract was fractionated into albumin, globulin, prolamin, acidic and basic glutelin protein fractions. These protein fractions were examined for the presence of an endogenous lectin receptor by SDS-polyacrylamide gel electrophoresis, western blot, affinity chromatography on a Sepharose 4B-Cratylia floribunda (CFL) lectin column and kinetic analysis in real time by surface plasmon resonance (SPR). Prolamin was the richest protein fraction although very poor in haemagglutinating activity. Basic glutelin was far the less interesting fraction for lectin activity and protein content, even though this fraction contains considerable amounts of carbohydrates. Lectin was present in all protein... Tipo: Info:eu-repo/semantics/article Palavras-chave: Protein-carbohydrate interaction; Surface plasmon resonance; Western blot. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000300003 Plant-insect interactions: an evolutionary arms race between two distinct defense mechanisms Braz. J. Plant Physiol. Mello,Marcia O.; Silva-Filho,Marcio C.. In this review, plant-insect interaction is discussed as a dynamic system, subjected to continual variation and change. Plants developed different mechanisms to reduce insect attack, including specific responses that activate different metabolic pathways which considerably alter their chemical and physical aspects. On the other hand, insects developed several strategies to overcome plant defense barriers, allowing them to feed, grow and reproduce on their host plants. This review foccuses on several aspects of this complex interaction between plants and insects, including chemical-derived substances, protein-derived molecules and volatile compounds of plants whereas metabolization, sequestration or avoidance are in turn employed by the insects. Tipo: Info:eu-repo/semantics/article Palavras-chave: Adaptation; Co-evolution; Herbivory. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000200001 Sensibilidade estomática ao ABA em função do pH e de níveis de Ca2+, NO3- e PO4(3-) na seiva do xilema Braz. J. Plant Physiol. Oliveira,Maria Neudes Sousa de; Oliva,Marco Antonio; Martínez,Carlos Alberto; Mercier,Helenice; Silva,Marco Aurélio Pedron e. A hipótese de que a sensibilidade estomática ao ácido abscísico (ABA) possa ser influenciada pelas características da seiva xilemática, como pH e concentração de Ca2+, NO3- e PO4(3-), foi testada em plantas de Lycopersicon esculentum L. var. Santa Clara submetidas a estresse hídrico induzido pela adição de PEG 6000 à solução nutritiva. Estimou-se a sensibilidade estomática ao ABA pela relação transpiração/ABA xilemático. Plantas intactas foram submetidas a estresse hídrico rápido e lento e determinaram-se as variações de pH e as concentrações de Ca2+, NO3- e PO4(3-) na seiva do xilema Também se estudaram os efeitos de diversas concentrações de Ca2+, NO3- e PO4(3-) sobre a transpiração em folhas destacadas imersas em seiva artificial contendo ABA exógeno.... Tipo: Info:eu-repo/semantics/article Palavras-chave: Lycopersicon esculentum L.; Estresse hídrico; Seiva xilemática; Transpiração. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000200006 Seed phytate content and phosphorus uptake and distribution in dry bean genotypes Braz. J. Plant Physiol. Coelho,Cileide Maria Medeiros; Santos,Júlio Cesar Pires; Tsai,Siu Mui; Vitorello,Victor Alexandre. Phytic acid is the major storage form of phosphorus in seeds of legumes and cereals. Since phytate can form complexes with proteins and minerals, reducing the digestive availability of these nutrients, it is usually regarded as an antinutrient, although recent work indicates that it has important beneficial roles as an antioxidant and anticarcinogen. Therefore, there is an interest in the assessment and manipulation of phytate contents in important food grains such as beans. The objective of this work was to compare eleven dry bean genotypes with regard to grain contents of P, phytate, inorganic P and protein and to examine if differences between genotypes could be explained by differences in grain protein content or in uptake and partitioning of P. Plants... Tipo: Info:eu-repo/semantics/article Palavras-chave: Inorganic phosphorus; Phaseolus; Phytic acid; Protein. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000100007 Portable chlorophyll meter for the quantification of photosynthetic pigments, nitrogen and the possible use for assessment of the photochemical process in Carica papaya L. Braz. J. Plant Physiol. Torres Netto,Alena; Campostrini,Eliemar; Oliveira,Jurandi Gonçalves de; Yamanishi,Osvaldo Kiyoshi. The techniques utilized to extract chlorophyll from plant materials are destructive and based on methods that use organic solvents. This study proposes the non-destructive quantification of chlorophyll and nitrogen concentration using a portable chlorophyll meter (SPAD-502). Further, was possible to establish relationships between chlorophyll fluorescence and SPAD-502 values. This methodology could save time, space and resources, and could be used for analysis of the photosynthetic processes. Papaya leaves (Solo and Formosa groups) of different ages were collected from 15-month-old plants cultivated in a commercial field in São Francisco de Itabapoana, Rio de Janeiro State (41(0):15W; 21(0):27S). Correlations were established between the chlorophyll... Tipo: Info:eu-repo/semantics/article Palavras-chave: Nutrient content; Photosynthetic pigments; SPAD-502. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000300004 Possible involvement of proteasome activity in ethylene-induced germination of dormant sunflower embryos Braz. J. Plant Physiol. Borghetti,Fabian; Noda,Fabio Nakamura; Sá,Cezar Martins de. Freshly harvested sunflower seeds (Helianthus annuus L., Asteraceae) present physiological dormancy localized at the embrionary axis which prevents germination at low temperatures. However, dormant embryos reach about 100 % germination when incubated with the phytohormone ethylene during imbibition. To examine whether proteinase activities are implicated in the breaking of dormancy by ethylene, dormant embryos were treated with the proteinase inhibitors leupeptin, E64 and the proteasome specific inhibitor clasto-lactacystin ß-lactone (lactacystin). A few embryos (< 10 %) germinated at 10 ºC in absence of ethylene but ethylene-treated embryos reached high germinability (~90 %) in the presence of leupeptin, E64, water and DMSO. On the other hand,... Tipo: Info:eu-repo/semantics/article Palavras-chave: Helianthus annuus; Dormancy; Ethylene; Lactacystin; Proteasome. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000200007 Secrets in secretions: genes that control nematode parasitism of plants Braz. J. Plant Physiol. Hussey,Richard S.; Davis,Eric L.; Baum,Thomas J.. The most evolutionary advanced adaptations for plant parasitism by nematodes are the products of parasitism genes expressed in their esophageal gland cells and secreted through their stylet into host tissue to control the complex process of parasitism. Molecular analyses of nematode parasitism genes are revealing the complexity of the tools a nematode possesses that enable it to attack plants and paints a more elaborate picture of host cellular events under specific control by the parasite than previously hypothesized. Interestingly, the majority of the nematode parasitism genes discovered encodes proteins unique to plant parasites. Identifying the complete profile of parasitism genes expressed throughout the parasitic cycle of a nematode is the key to... Tipo: Info:eu-repo/semantics/article Palavras-chave: Esophageal gland cells; Nematode parasitism; Parasitome; Parasitism genes; Secretion. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000300002 Indole-3-acetic acid metabolism in normal and dwarf micropropagated banana plants (Musa spp. AAA) Braz. J. Plant Physiol. Zaffari,Gilmar Roberto; Peres,Lázaro Eustáquio Pereira; Tcacenco,Fernando Adami; Kerbauy,Gilberto Barbante. Nanism is one of the most frequent type of mutant in micropropagated banana plants from the Cavendish subgroup. The present study aimed at studying some of the hormone factors involved in this type of mutation. Rhizomes from normal and dwarf plants from the cultivar Grand Naine were incubated for 5 d in the presence of [³H]-L-tryptophan, [³H]-indole-3-acetic acid and gibberellin, to quantify the endogenous levels of indole-3-acetic acid-ester, indole-3-acetic acid-amide, free indole-3-acetic acid, and cytokinins. The endogenous levels of indole-3-acetic acid and its ester- and amide-conjugated forms were measured in normal and dwarf plants incubated for 30 d with gibberellin, indole-3-acetic acid, and L- and D-tryptophan. In normal plants, the use of... Tipo: Info:eu-repo/semantics/article Palavras-chave: Indole-3-acetic acid metabolism; Growth regulators; Somaclonal variation. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000300005 Caracterização de ER49, um fator de elongação da síntese de proteínas do tipo Ts, expresso durante a maturação do fruto de tomate Braz. J. Plant Physiol. Chaves,Ana Lúcia S.; Silva,J.A.; Pech,J.-C.; Latche,A.; Bouzayen,M.; Zegzouti,H.; Rombaldi,Cesar V.. O etileno, conhecido, sobretudo, como o fitormônio da maturação de frutos, está envolvido em vários processos fisiológicos, atuando na regulação da expressão de grande número de genes. O clone parcial de cDNA ER49 foi previamente isolado mediante a técnica do "Differential Display". A obtenção e a análise da seqüência completa confirmaram as homologias significativas com fatores de elongação da síntese de proteínas do tipo Ts. Tais proteínas são responsáveis pela reciclagem do complexo EF-Tu•GDP, que atua na ligação do aminoacil-RNAt ao ribossomo. A predição da seqüência protéica permitiu a detecção de um peptídio sinal de endereçamento para a mitocôndria e dos domínios TS-N e EF-Ts. A modelagem da estrutura terciária mostrou que ER49 poderia interagir com... Tipo: Info:eu-repo/semantics/article Palavras-chave: EF-Ts; Etileno; Frutos climatéricos; Lycopersicon esculentum; Regulação pós-transcricional. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000100003 Activation of nitrate reductase of cashew leaf by exogenous nitrite Braz. J. Plant Physiol. Viégas,Ricardo Almeida; Silveira,Joaquim Albenísio Gomes. Nitrate reductase (NR) plays a central role in plant primary metabolism and exhibits complex regulation mechanisms for its catalytic activity. There is controversy in the literature concerning the possible direct effect of NO2- on the stimulation and/or activation of NR activity. The influence of NO2- was studied on the NR activity in the leaves of 30-day-old cashew (Anacardium occidentale L.) seedlings. Addition of NO2- to the reaction mixture containing leaf enzymatic extract resulted in a remarkable increase in NR activity. A trace amount (5 mumol.L-1) of NO2- was required to achieve full NR activity. The in vitro NR-activity showed a steady time-dependent increase when incubated in the presence of only NO3- + NO2-. In contrast, in vitro NR activity was... Tipo: Info:eu-repo/semantics/article Palavras-chave: Anacardium occidentale; Enzymes; NADH; Nitrate metabolism; Nitrate reductase. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000100005 The effect of chilling on the photosynthetic activity in coffee (Coffea arabica L.) seedlings: The protective action of chloroplastid pigments Braz. J. Plant Physiol. Oliveira,Jurandi Gonçalves de; Alves,Pedro Luis C.A.; Magalhães,Antonio Celso. Coffea arabica is considered to be sensitive to low temperatures, being affected throughout its entire life cycle. Injury caused by chilling (low temperatures above zero degree centigrade) is characterized primarily by inhibition of the photosynthetic process. The objective of this work was to evaluate the role of photosynthetic pigments in the tolerance of coffee (C. arabica L.) seedlings to chilling. The evaluation the photosynthetic activity was made by emission of Chl a fluorescence at room temperature (25 ºC) in vivo and in situ, using a portable fluorometer. The pigment content was obtained by extraction with 80 % acetone, while estimation of membrane lipid peroxidation was determined by measuring the MDA content in leaf tissue extracts. The results... Tipo: Info:eu-repo/semantics/article Palavras-chave: Chlorophyll a fluorescence; Coffee; Lipid peroxidation; Photosynthetic pigments. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000200003 Expression of heat shock protein and trehalose-6-phosphate synthase homologues induced during water deficit in cotton Braz. J. Plant Physiol. Nepomuceno,Alexandre Lima; Oosterhuis,Derrick; Stewart,James McD; Turley,Rickie; Neumaier,Norman; Farias,José Renato Bouças. Tolerance to drought in plants is not a simple trait, but a complex of mechanisms working in combination to avoid or to resist water deficit. Genotypes that differ in tolerance to water deficit may show qualitative and quantitative differences in gene expression when submitted to drought periods. Four cotton (Gossypium hirsutum L.) genotypes (Siokra L-23, Stoneville 506, CS 50 and T-1521) with contrasting responses to water deficit stress were studied using the Differential Display (DD) technique to identify and isolate genes which may differ among them. Fifty-two cDNA fragments differentially expressed during water deficit were isolated, cloned and sequenced. Search of gene bank databases showed that two cDNA clones, A12B15-6 and A12B13-1, have high... Tipo: Info:eu-repo/semantics/article Palavras-chave: Calmodulin; Drought; Gene expression; Gossypium hirsutum L.; Trehalase. Ano: 2002 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202002000100002 Registros recuperados: 360 Primeira ... 1 2 3 4 5 6 7 8 9 ... Última

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