Day-night Differences in the Accumulation and Translocation of Ions by Tobacco Plants

More K(42), Rb(86), and Br(82) was accumulated by intact tobacco plants and root systems from detopped plants during the night than during the day when studies for both periods were made in dark rooms controlled at 18 degrees . More, however, was translocated to shoots during the day than during the night in intact plants. This latter effect parallels the periodicity of exudation in root systems from detopped plants.