Fig. 7

Effect of methionine, tryptophan, glycine betaine and lysine foliar spray on (A) catalase, (B) peroxidase and (C) superoxide dismutase activity in Zea mays plants grown under salt stress (120 mM NaCl). Data presented in the graphs is the mean of three replicates ± standard errors. Bars sharing similar letters are not significantly different at p < 0.05.