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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11847
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Item Função bioquímica da via daslipoxigenases em plantas de soja submetidas ao ataque de mosca-branca (Bemisia argentifolii)(Ciência e Agrotecnologia, 2004-03) Silva, Francine Barbosa; Oliveira, Maria Goreti de A.; Brumano, Maria Helena N.; Pires, Christiano Vieira; Almeida, Fabrício Tadeu de; Oliveira, Joel Antônio; Pilon, Anderson Martins; Silva, Carlos Henrique Osório; Moreira, Maurilio AlvesNeste trabalho, avaliou-se a capacidade da planta de soja de uma cultivar comercial, IAC-100, e de um genótipo IAC- 100 TN que apresenta ausência de lipoxigenases nas sementes de responderem ao ataque de mosca-branca (Bemisia argentifolii) pela via das Lipoxigenases. Foi realizada a caracterização cinética do pool de lipoxigenases. Os valores de KMapp decresceram nas plantas atacadas, sugerindo uma alteração no pool de lipoxigenases foliares. Valores similares de KMapp, entre os genótipos, indicam que a remoção de lipoxigenases de sementes não interferiram na expressão de lipoxigenases em folhas. Ocorreu aumento significativo na produção de inibidores de proteases. Com esses resultados, infere-se que a produção de inibidores de proteases está envolvida no mecanismo de defesa de soja ao ataque da mosca-branca.Item Efeito da aplicação foliar de ácidos graxos na "via das lipoxigenases" de plantas de soja(Química Nova, 2002-11) Batista, Rosa Bárbara; Oliveira, Maria Goreti de Almeida; Pires, Christiano Vieira; Lanna, Anna Cristina; Gomes, Maria Regina Araújo; José, Inês Chamel; Piovesan, Newton Deniz; Rezende, Sebastião Tavares de; Moreira, Maurilio AlvesThe involvement of lipoxygenase isozymes in several physiological processes of plants has been described but their role is not well understood and more biochemical studies are needed to elucidate the role of the "Lipoxygenase Pathway" in plant physiology. Thus, the biochemical and kinetic characterization of a lipoxygenases "pool" from soybean leaves was carried out. Two genotypes were used: IAC-100 (a normal variety having lipoxygenases in the seeds) and IAC-100 TN (genetically modified genotype, which is devoid of lipoxygenases in the seeds). The plants were submitted to the application of fatty acids (lipoxygenase substrates) on leaves. The results of the biochemical and kinetic studies of lipoxygenase isozymes from leaves of the two genotypes analysed showed that genetic removal of lipoxygenase from seeds did not affect the response of the plant to the treatment, since both genotypes showed similar results.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 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 Low linolenic soybeans for biodiesel: Characteristics, performance and advantages(Fuel, 2012-06-16) Santos, Eleonice Moreira; Piovesan, Newton Deniz; Barros, Everaldo Gonçalves de; Moreira, Maurilio AlvesSoybean is one of the main raw materials used for biodiesel production. However, the polyunsaturated fatty acids present in soybean seeds are not desirable for this purpose due to their low oxidative stability. Therefore, it is expected that the use of soybean cultivars with low linolenic acid content for biodiesel production will improve its oxidative stability and the cold filter plugging point (CFPP). This work presents the main characteristics, the advantages and performance of low linolenic acid soybean (LL) as compared to a conventional soybean variety (CO) for biodiesel production. The results showed that LL oil and protein contents were similar to those of CO. Phosphatide concentration was higher in LL oil, while total tocopherol content was lower in relation to CO. With respect to LL biodiesel performance, oxidative stability was much higher than that produced from CO, and the CFPP did not change even with the improved fatty acid profile of LL.