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.
Peroxidases; gamma radiation; sweet potato; Ipomoea batatas; convovulaceae
