Table 3.

Enzymatic activities in roots of Alfalfa after cultivation for 7 days in nutrient medium with or without Cd and Si.

Treatments	CAT min-1 [(mg protein)-1]	APX min-1 [(mg protein)-1]	POD min-1 [(mg protein)-1]	SOD [U.mg-1 protein]	GR [nmol.NADH.min-1mg protein-1]	H2O2 content μmol g-1 FW
Cd-	1.07 ± 2.26a	3.46 ± 0.50a	0.20 ± 0.03a	0.19 ± 0.02b	0.51 ± 0.38a	0.33 ± 0.07a
Cd+	1.85 ± 0.46b	1.45 ± 0.32b	0.24 ± 0.05a	0.09 ± 0.03a	0.23 ± 0.10a	2.94 ± 0.79b
Cd+ Si+	3.08 ± 0.26c	3.82 ± 0.80a	0.20 ± 0.03a	0.19 ± 0.03b	0.16 ± 0.05a	1.10 ± 0.24a
Cd- Si+	0.61 ± 0.26a	3.94 ± 1.21a	0.21 ± 0.02a	0.13 ± 0.01b	0.23 ± 0.02a	0.78 ± 0.13a

Different letters in each column indicate significant differences between mean ± SD of treatments (n = 3) at a P < 0.05 significance level.