Fig. 3

Determination of physiological indices of the three Zygophyllum species under salt stress. MDA content (a), chlorophyll content (b), proline content (c), CAT activity (d), SOD activity (e) and POD (f) activity in leaves of three Zygophyllum species treated with different concentrations of NaCl. The values are the means ± SD from three replicates. Different letters indicate significant differences at P < 0.05 according to Duncan’s multiple range test