Alterações histologicas e bioquimicas na formação de raizes em folhas destacadas de pereskia grandifolia haw

AUTOR(ES)
DATA DE PUBLICAÇÃO

1983

RESUMO

Abstract: Detached leaves of Pereskia grandifolia root easily when kept in light, not requiring any treatment with growth regulators. Rooting is inhibited when leaves are kept in the dark or treated with gibberellic acid. The first histological changes observed in the petiole base that lead to the formation of a callus in this region take place between 48 and 72 hours after the detachment of the leaves from the mother plant, in all three treatments studied (light, dark, GA3 in light). Parenchima cells from the cortex, phloem and xylen go through dediferentiation and become meristematic, contributing to the formation of the callus. Formation of root primordia however occurs only in petioles of control leaves kept in light. In the calluses of these petioles a meristem is organized to give rise to the primordium apex, around the twelfth day of the experiment. Analysis of carbohydrate contents present in leaf blades and petioles during the cultivation period shows greater variations in the petioles as compared to leaf blades. The increase in the contents of both reducing and total sugars observed during the cultivation period was shown to be more intense in petioles of GA3-treated leaves than in control-leaves, whereas a decrease in the contents of these sugars was observed in petioles of dark treated leaves, in response to non-photosynthetic activity of these tissues. ...Note: The complete abstract is available with the full electronic digital thesis or dissertations

ASSUNTO(S)

botanica plantas

ACESSO AO ARTIGO

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