Supplementary CaCl2 ameliorates wheat tolerance to NaCl

Nine-day-old seedlings of two wheat cultivars

(Misr1 and Sakha93) were treated with NaCl at 75, 150 and

225 mM for 15 days with or without the presence of

10 mM CaCl2. All concentrations of NaCl led to significant

decreases in fresh and dry weights of only Sakha93;

however, Misr1 seemed to be affected only at the highest

concentration. Nonetheless, growth parameters of both

cultivars under normal conditions were most likely similar.

On the other hand, lipid peroxides (as MDA) and H2O2

were greatly accumulated particularly in Sakha93; significant

increases were detected in Misr1 treated only at

225 mM. Also, all concentrations of NaCl decreased GSH

content in Sakha93; nevertheless, there were no great differences

among both cultivars under normal conditions. On

the other hand, the activities of the enzymatic antioxidants,

GR, GST, CAT and POD were unaffected in Misr1 by all

concentrations but inhibited in Sakha93. AOX responded

differently to NaCl, there were decreases in Misr1 by 75

and 225 mM and in Sakha93 by 75 and 150 mM. However,

the application of CaCl2 alleviated the impacts of NaCl;

there was a retraction in growth reduction in Misr1 to reach

most likely those of the control. In addition, the accumulated

MDA and H2O2 were greatly counterbalanced. On the

contrary, the decreased GSH contents seemed unrecovered

in Sakha93 in spite of the alleviations in magnitudes.