Brazilian Archives of Biology and Technology (Jun 2002)
Changes in electrophoretic profiles of Ipomoea batatas (sweet potato) induced by gamma radiation
Abstract
The ability of nodal segments of Ipomoea batatas to differentiate shoots and roots was evaluated after gamma irradiation. Shoot differentiation was less sensitive to irradiation than roots. However, at 90 Gy, no shoot was able to regenerate a new plant; in contrast 76 % of the roots from irradiated nodal segments continued to grow. The gamma radiation also induced changes in electrophoretic profiles of peroxidases of storage roots. Plants originated from irradiated storage roots presented changes in leaf peroxidase profiles very similar to those produced by leaves directly irradiated. The peroxidase profile of absorbent roots from irradiated storage roots was different from that obtained from directly irradiated absorbent roots.A capacidade de Ipomoea batatas diferenciar parte aérea e raízes foi avaliada após irradiação com raios gama. A diferenciação da parte aérea foi menos sensível que a das raízes. Contudo, na dose de 90 Gy nenhum broto diferenciado regenerou planta, enquanto 76 % das raízes diferenciadas dos segmentos nodais irradiados manteve o crescimento. A radiação também induziu mudanças no perfil elotroforético de isoperoxidases. Plantas originadas de raízes tuberosas irradiadas apresentaram alteração no perfil de isoperoxidases foliares semelhantes ao perfil de folhas diretamente irradiadas. O perfil de isoperoxidases de raízes absorventes irradiadas diretamente não apresentou o mesmo padrão do perfil das raízes absorventes desenvolvidas de raízes tuberosas irradiadas.
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