Metabolismo de ureideos e asparagina durante a ontogenia do fruto de plantas de soja nodulados e não-nodulados

AUTOR(ES)
DATA DE PUBLICAÇÃO

1982

RESUMO

The synthesis and accumulation of reserve proteins in seeds require a large supply of reduced nitrogen. Generally, the transport of nitrogen from other parts of the plant involves a few specific compounds, the nature of which depends on the species and growth conditions. The fixation of N 2 by Rhizobium in symbiotic association with soybeans, cultivated in the absence of mineral nitrogen, leads to the incorporation of atmospheric nitrogen in ureides (allantoin and allantoic acid). These compounds form the main nitrogenous components found in the transport stream of nodulated soybeans. On the other hand, soybeans grown in the absence of Rhizobium and with NO3 nitrogen source, contain asparagine as the predominant as transport form of nitrogen. The accumulation of protein in the fruits of such plants will depend, therefore, on their ability to utilize these compounds for the synthesis of amino acids. The objectives of the present study were: first, demonstrate the presence of the enzymes presumed to be involved in the utilization of these compounds (i.e. allantoinase and asparaginase). Second, determine the effect of this drastic change in the transport of nitrogen from mainly ureides (nodulated plants) to asparagine (non-nodulated plants) on the appearance of these enzymes during fruit ontogeny specifically in the pods, cotyledons and teguments... Note: The complete abstract is available with the full electronic digital thesis or dissertations.

ASSUNTO(S)

ontogenia biologia do desenvolvimento soja

ACESSO AO ARTIGO

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