SODIUM RECIRCULATION AND LOSS FROM PHASEOLUS-VULGARIS L

In a split-root experiment, 22Na was supplied to Phaseolus vulgaris L. roots emerging from the stem, 2.5 cm above the main roots. Sodium exported from these upper roots was translocated a short distance upward in the stem and downward to the main roots. Most of the 22Na arriving in the main roots was lost to the medium.Sodium loss from P. vulgaris roots into KCI or NaCl was similar and was not affected by oligomycin.The results confirm a previous hypothesis regarding the mechanism of sodium exclusion from the tops of sodium non-accumulator plants. © 1979, Annals of Botany Company.