Monovalent ions in salt-treated plants.

<p>Leaf contents of (A) sodium (Na⁺), (B) chloride (Cl^-), (C) potassium (K⁺), and (D) K⁺/Na⁺ ratios, in the selected <i>Plantago</i> species, after four weeks of treatment with the indicated NaCl concentrations (means ± SD, n = 5). Different lower case letters within each species indicate significant differences according to Tukey test (α = 0.05).