Comparison of Photassium and Sodium Uptake by Barley Roots at High and Low Salt Status

Abstract

Measurements are described of the uptake of sodium and potassium by barley roots at low salt status. It was found that initially there was little preference for potassium in the salt accumulated, but about 5 hr after the start of salt accumula· tion net uptake of sodium decreased markedly, and thereafter much more potassium was taken up than sodium. The roots reached salt saturation in about 24 hr. The decreased sodium uptake was due to a reduction in sodium influx.