• Ion transport;
  • water transport;
  • excised roots;
  • Sinapis alba L


Ion and water transport were measured in young mustard seedlings which had been grown in the dark on a simple culture medium. The growth of seedlings was exponential during the period 2 to 5 d from germination, though there was a decline in the rate of respiration with age. A comparison of the fluxes from excised roots with those in the roots of intact plants showed that the fluxes of potassium and chloride were much greater in intact plants, and it is argued that transport to the shoot might be regulated by some factors from the intact shoot. The flux of water was similar in both systems.