The fate of 137Cs in senescing roots of Eriophorum vaginatum L.

The fate of Cs-137 in senescing roots was investigated by deliberately increasing the proportion of dead roots in half of the root system of previously Cs-137-labelled Eriophorum vaginatum L. (hare's-tail cotton-grass) plants by using peg (polyethylene glycol) to induce a severe water deficit in a split-root hydroponic system. The rooting solutions and treated and untreated plants were analysed over a 21-day period subsequent to radiolabelling. The loss of Cs-137 from roots did not increase with increasing proportion of dead root and there was no evidence to suggest that Cs-137 from senescing roots was recovered and translocated to the shoot or to the remaining live roots. Cs-137 present in roots killed by peg remained in the dead roots. (C) 1998 Elsevier Science Ltd. All rights reserved.