Translocation of 14 C in Adventitiously Rooting Calluna vulgaris on Peat

Abstract

Seasonal variation in translocation of 14C-labeled assimilates showed that 14C-translocation within woody tissue was mainly limited to the phytomass produced during the last 8 yr. Independent of overgrowth of basal stem segments or decumbent sections by Sphagnum, or of subsequent adventitious rooting, the allocation followed a negtive exponential from the assimilating units down the plant, and reached negligible values in 8-yr old wood. Translocation to fine roots was, however, mainly restricted to the shallow roots. Already at .apprx. 10 cm depth, the life roots contained only .apprx. 5% of the concentration in the fine roots in the surface. During spring and autumn, translocation to belowground parts dominated. During summer the main translocation was within the aboveground green shoots and flowers. Here most of the allocated 14C was irreversibly bound. There were only weak indications of accumulation of mobile 14C-compounds in the woody parts near the soil surface.