Abstract
The influx of K+ into excised roots of barley (Hordeum vulgare L.) and ryegrass (Lolium multiflorum L.) previously grown with or without K+ was measured in K+ solutions ranging in concentration from 0.01 to 50 mM. In both species the K+ influx was lower in the roots with high K+ content. The extent of reduction by high internal [K+] decreased with external concentration above 1 mM. These results support the contention that at high external concentrations passive diffusion makes significant contributions to observed fluxes.
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Glass, A.D.M., Dunlop, J. The influence of potassium content on the kinetics of potassium influx into excised ryegrass and barley roots. Planta 141, 117–119 (1978). https://doi.org/10.1007/BF00387753
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DOI: https://doi.org/10.1007/BF00387753