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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11847
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Item Genetic distances in soybean based on RAPD markers(Bragantia, 1999) Corrêa, Ronan Xavier; Abdelnoor, Ricardo Vilela; Faleiro, Fábio Gelape; Cruz, Cosme Damião; Moreira, Maurilio Alves; Barros, Everaldo Gonçalves DeFour methods were applied to determine pairwise genetic distances among five soybean genotypes which are potential genitors for a mapping population. Additionally, individual plants from the most divergent pair of genotypes were evaluated by the RAPD technique to determine their degree of homozygosity. Genetic distances based on RAPD data were calculated by the modified Rogers' distance, and also by the following arithmetical complements of similarity: simple match, Nei and Li, and Gower. These genetic distances were similar, presenting a correlation coefficient ranging from 0.99 to 1.00. In all four methods lines UFV 91-717 and Ichigowase were the most divergent ones (4.53 to 21.43%). DNA samples from five plants from each of the two most divergent genotypes were amplified with 28 different primers. Among the amplified products, only five were polymorphic in each group (2.10%), demonstrating their high intragroup degree of homozygosity. These homozygosity were maintained when DNA samples from 12 plants from each of the two most divergent genotypes were amplified. These parameters were extremely useful for the confirmation of the chosen pair of genitors to generate a mapping population.Item Phenylcoumarins from Kielmeyera elata(Phytochemistry, 1999-06) Gramacho, R.da S; Oliveira, Tânia Toledo de; Queiroz, Maria Eliana L.R de; Neves, Antonio A.; Nagem, Tanus J.; Saddi, NagibFriedelin, the 4-phenylcoumarins mammeisin, 4-phenyl-5-hydroxy-6-(3-methyl-1-oxobutyl)-2′-(1-hydroxy-1-methylethyl)-3′,4′-dihydro(5′,4′:7,8) furancoumarin, and mammeigin have been purified from the stem of Kielmeyera elata. These compounds have previously been reported for the same species. In addition, a new derivative of mammeigin has been isolated and identified as 4-phenyl-5-hydroxy-6-(3-hydroxymethyl-1-oxo-butyl)-2′,2′-dimethyl(6′,5′:7,8)pyrancoumarin.Item Lipoxygenases affect protease inhibitor levels in soybean seeds(Plant Physiology and Biochemistry, 1999-06) Oliveira, Maria Goreti de Almeida; Carvalho, Willam Lima de; Barros, Everaldo Gonçalves de; Moreira, Maurilio AlvesNo physiological role has been assigned to lipoxygenases (LOX) (linoleate:oxygen oxidoreductase, EC 1.13.11.12) present in soybean seeds. The development of LOX null lines has provided an ideal genetic material to determine possible physiological roles for seed LOX. Genetic elimination of seed LOX was followed by a corresponding decrease in the levels of protease inhibitors in soybean seeds. Participation of LOX in the biosynthetic pathway leading to jasmonates, which activate protease inhibitor genes, has been demonstrated in leaves of several plant species. It is conceivable that LOX has a similar role in the developing seed.Item Cyclic AMP and low molecular weight effector(s) present in yeast extract are involved in pectin lyase production by Penicillium griseoroseum cultured on sucrose(Applied Biochemistry and Biotechnology, 1999-02) Pereira, Maria Cristina Baracat-; Coelho, Jorge Luiz Cavalcante; Minussi, Rosana Cristina; Alves, Virgínia Maria Chaves; Brandão, Rogelio Lopes; Silva, Daison OlzanyPectin lyase (PL) induction by organic and inorganic components of yeast extract (YE) was evaluated in Penicillum griseoroseum, cultured in a mineral medium containing sucrose, by determining PL activity (A 235) and mycelial growth (mycelial dry weight). The lowest YE concentration that promoted significant PL induction without acting as a carbon source for the fungus corresponded to 0.0075%. Neither calcined YE nor a nutrient solution containing micronutrients induced PL production, indicating that the inducer was an organic compound. Vitamins, phospholipid components, amino acids, and nitrogenous bases were tested in place of YE and promoted no significant PL induction. APL inducer compound was found to be soluble in the nucleotide fraction obtained during extraction of YE. The inducer was shown to be a thermostable polar substance dialyzable at 2000 Daltons, hydrolyzable by HCl, and activated by boiling for up to 60 min. Cyclic AMP (cAMP) exogenously added to the culture medium at 5 and 10 mM was capable of inducing PL in P. griseoroseum grown on sucrose, suggesting that at least one compound may be present in YE acting in a cooperative fashion for the maintenance of high levels of cAMP in to the cell. PL activity and the level of cAMP inside the fungal cells increased after the addition of YE to the culture medium, suggesting the participation of this messenger in this enzyme's synthesis.Item Resistência do feijoeiro-comum a quatro raças de Uromyces appendiculatus(Revista Ceres, 1999-01) Moreira, Maurílio Alves; Barros, Everaldo Gonçalves de; Paula Jr., Trazilbo José de; Ragagnin, Vilmar Antõnio; Vinhadelli, Wender Santos; Faleiro, Fábio GelapeForam inoculadas 13 variedades de feijoeiro-comum recomendadas para plantio em Minas Gerais e quatro acessos (PI) utilizados no CIAT como fonte de resistência às raças 4, 8, 10 e 11 de Uromyces appendiculatus, fungo causador da ferrugem. Foi avaliada a frequência de infecção (FI) e estimado o tamanho médio das pústulas (TMP). A maioria das variedades recomendadas para Minas Gerais apresentou alta FI para todas as raças. A variedade Ouro Negro destacou-se como a mais resistente, sendo imune a três das quatro raças avaliadas. Com relação às PI, todas foram imunes a pelo menºs uma raça. A PI 181395 destacou-se como a melhor fonte de resistência à ferrugem, sendo imune a todas as raças testadas. A estimativa do TMP foi importante para confirmar e complementar os dados obtidos pela FI. Pôde-se observar que nas variedades que apresentaram maior FI o TMP foi superior a 300 μm de diâmetro.Item Hypolipidaemic effects of naringenin, rutin, nicotinic acid and their associations(Pharmacological Research, 1999-05-26) Santos, K.F.R.; Oliveira, T.T.; Nagem, T.J.; Pinto, A.S.; Oliveira, M.G.A.Atherosclerosis can be defined as being a disease of coronary circulation. The present work evaluates the action of the naringenin, rutin, nicotinic acid, isolated and in association, on the metabolism of lipids. Cholesterol, cholesterol HDL, and triacylglycerols have been dosed after retreat of blood, following the administration of the compounds dissolved in propylene glycol by intraperitoneal route in doses of 5 mg kg^−1body wt. Results evidence that naringenin and nicotinic acid, isolated as well as their association with naringenin and nicotinic acid–rutin, present the largest percentual reduction of cholesterol. On the other hand, the best results for cholesterol-HDL have been obtained with naringenin, while rutin has shown the best triacylglycerols levels.Item Variabilidade genética em biotipos de leiteiro de Londrina/PR(Planta Daninha, 1999-09-16) Vasconcelos, Maria José V. de; AbdelnoorI, Ricardo V.; Karan, Décio; Almeida, Álvaro M. R.; Oliveira, Maurílio F. de; Barros, Everaldo G.; Moreira, Maurílio A.Euphorbia heterophylla, também conhecida como amendoim-bravo ou leiteira, é considerada planta invasora importante em mais de 56 países, inclusive no Brasil, tendo acarretado perdas de até 33 % na cultura da soja. Fenotipicamente, é uma espécie de características variáveis, especialmente em relação ao formato do limbo foliar. Esta variabilidade fenotípica tem sido utilizada para diferenciar e classificar as plantas, sugerindo a vários autores que a leiteira seria, de fato, constituída por diferentes espécies. Para estudar a variabilidade genética a nível de DNA entre plantas de Euphorbia heterophylla, que apresentam folhas morfologicamente diferentes, foram analisadas dez plantas diferentes coletadas em campos de soja, em Londrina/PR. As plantas foram transplantadas para casa-devegetação e o DNA das folhas foi extraído para análise pela técnica de RAPD. Vinte seis diferentes "primers", de dez nucleotídeos de sequência aleatória, geraram total de 102 bandas de DNA, sendo 38 delas polimórficas. A distância genética entre os indivíduos foi calculada em função da presença e da ausência das bandas, variando de 1 a 39% entre plantas. A análise de agrupamento dividiu as plantas em dois grupos, considerando limite de distância relativa de 22%. Os grupos gerados separaram nitidamente as plantas quanto ao formato do limbo foliar (estreito ou arredondado) e quanto á ramificação (densa ou normal).