The interactions between maize, sorghum, wheat and rice plants and Herbaspirillum seropedicae were examined microscopically following inoculation with the H. seropedicae LR15 strain, a Nif(+) (Pnif::gusA) mutant obtained by the insertion of a gusA-kanamycin cassette into the nifH gene of the H. seropedicae wild-type strain. The expression of the Pnif::gusA fusion was followed during the association of the diazotroph with the gramineous species. Histochemical analysis of seedlings of maize, sorghum, wheat and rice grown in vermiculite showed that strain LR15 colonized root surfaces and inner tissues. In early steps of the endophytic association, H. seropedicae colonized root exudation sites, such as axils of secondary roots and intercellular spaces of the root cortex; it then occupied the vascular tissue and there expressed nif genes. The expression of nif genes occurred in roots, stems and leaves as detected by the GUS reporter system. The expression of nif genes was also observed in bacterial colonies located in the external mucilaginous root material, 8 days after inoculation. Moreover, the colonization of plant tissue by H. seropedicae did not depend on the nitrogen-fixing ability, since similar numbers of cells were isolated from roots or shoots of the plants inoculated with Nif(+) or Nif(-) strains.

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Compostos de madeiras têm sido utilizados na elaboração de bebidas alcoólicas como alternativa envelhecimento tradicionalmente realizado em tonéis de carvalho. Neste trabalho, quatro extratos de carvalho, comercializados para produção de bebidas alcoólicas, foram adicionados branca, visando agregar propriedades sensoriais como coloração, sabor e aroma. As cachaças com os quatro extratos foram analisadas quanto à acidez, ganho e estabilidade da coloração. sensoriais também foram executadas. Os resultados mostraram que a adição dos extratos resultou em aumento de acidez da aguardente, bem como promoveu incrementos nos atributos considerando a cachaça branca usada, com diferenças na estabilidade do produto final.