Osmoregulation in higher plants: Effects of NaCl salinity on non-nodulated phaselous aureus L. I. growth and mineral content

Abstract

The adaptation, growth and changes in mineral composition of Phaseolus aureus L. were studied at six levels of NaCl, ranging from 10 to 200 mM. Plants tolerated up to 150 mM NaCl in the growth medium although their growth and mineral composition were adversely affected. Accumulation of Na+ in plant tissue increased with increasing NaClext reaching toxic concentrations and inhibited transport of different inorganic ions. K+ constituted only about 10 % of the total mineral content of plants grown in 150 mM NaCl as against 55 % in the controls. The principal balancing anion to counter Na+ accumulation was Cl−. ‘Ion excess’ in the plant is suggested to be the cause of reduced growth. The behaviour of P. aureus under condition of salt stress is discussed.