Climacoptera crassa is an annual native halophyte species with a great potential for use in urban landscape. In the present study, the morpho-physiological responses of C. crassa to salinity and heavy metal stresses were evaluated and the associated mechanisms were compared. For this study, the plant seedlings were exposed separately to various concentrations of NaCl (0-700mM) or heavy metals cadmium (Cd) and lead (Pb) (0-2 mM). Our results indicated that C. crassa seedlings were able to survive at 700 mM NaCl, however, the optimum growth of seedlings were observed at 500 mM salinity. Moreover, low concentration of the heavy metals had positive impact on the plant growth. This experiments showed that the increase in both salinity and heavy metal levels in the culture medium is coupled with the increase in proline, peroxide and sugar content in seedlings. However, these responses were more pronounced under heavy metal stress. Our results suggested that in response to heavy metal and salinity stresses, C. crassa uses the same physiological mechanisms. Overall, C. crassa was identified as a highly tolerant taxa to salinity that can also survive the presence of low to moderate amount of Cd and Pb.

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