Cd-induced growth reduction in the halophyte Sesuvium portulacastrum is significantly improved by NaCl.

The effects of Cd(2+) and NaCl, applied together or separately, on growth and uptake of Cd(2+) were determined for the halophyte Sesuvium portulacastrum L. Seedlings were cultivated in the presence of 50 or 100 micromol L(-1) Cd(2+) alone or combined with 100 or 400 mmol L(-1) NaCl. Data showed that alone, Cd(2+) induced chlorosis, necrosis, and inhibited growth. Addition of NaCl to Cd(2+)-containing medium restored growth and alleviated the toxicity, however. NaCl also enhanced the amounts of Cd(2+) accumulated in the shoots. All Cd(2+) treatment reduced K(+) and Ca(2+) uptake and transport to the shoots. Accumulation of Na(+) in the shoots was not affected by Cd(2+), however. Thus S. portulacastrum maintained its halophytic characteristics in the presence of Cd(2+). We suggest this halophyte could be used for phytoextraction of Cd(2+) from salt-contaminated sites.