Aufnahme radioaktiver Stoffe durch Erdbeer· und Rebenblätter

Abstract

Radioactive strontium in the form of an aqueous solution of 85 5rCl 2 was taken up by the leaves of strawberry plants and grapevines at different rates. Only a limited amount was transported from · the contaminated leaves into other plant organs. However, no strontium was found in the fruit. In contrast, radioactive caesium applied as an aqueous solution of 134CsCI was taken up very quickly from the leaf surface, transported from there to other plant parts and released to some extent into the soil via the roots. In our investigations, strawberry fruit showed a high caesium content. The caesium content in grape berries rose during growth and decreased again in a late phase of maturation and the nuclide was partly redistributed to other plant parts. Caesium reaching the soil may interact with day particles resulting in a very limited availability for plants. First results of investigations with grapevines in hydroculture demonstrated a close relationship between potassium supply and caesium release. The foliar up· take of radioactive strontium into plants is minor and represents therefore a negligible risk for the consumer of fruits. Radio· active caesium nuclides may however reach the human food chain through the leaves of food plants.