Table 5: Antioxidants status in different parts of cotton seedlings upon their exposure to Cd stress for 24-hour duration.

AntioxidantsParts
RootsStemsLeaves
0 µM Cd500 µM Cd0 µM Cd500 µM Cd0 µM Cd500 µM Cd

SOD (U/mg protein)275.25 ± 1.69b  
(0.00)
324.67 ± 6.13a  
(17.95)
267.13 ± 8.21a  
(0.00)
284.50 ± 1.94a  
(6.50)
255.82 ± 21.26b  
(0.00)
344.92 ± 5.09a  
(34.83)
APX (µM/min/mg protein)0.51 ± 0.17a  
(0.00)
0.41 ± 0.24a  
(−20.04)
1.43 ± 0.95a  
(0.00)
0.37 ± 0.10a  
(−74.50)
3.31 ± 0.16a  
(0.00)
1.84 ± 0.35a  
(−44.43)
CAT (µM/min/mg protein)0.030 ± 0.02a  
(0.00)
0.035 ± 0.01a  
(12.37)
0.11 ± 0.02a  
(0.00)
0.02 ± 0.010b  
(−83.17)
0.21 ± 0.010a  
(0.00)
0.57 ± 0.02a  
(169.09)
POD (µM/min/mg protein)7.48 ± 0.69a  
(0.00)
4.93 ± 0.33b  
(−34.09)
2.62 ± 0.13b  
(0.00)
3.72 ± 0.15a  
(41.85)
5.07 ± 0.14b  
(0.00)
8.03 ± 0.39a  
(58.26)
GR (µM/min/mg protein)0.22 ± 0.03a  
(0.00)
0.03 ± 0.08a  
(−85.10)
0.05 ± 0.02b  
(0.00)
0.18 ± 0.02a  
(244.76)
0.17 ± 0.02b  
(0.00)
0.27 ± 0.03a  
(54.59)

Values are the means ± SE of three replications. Variants possessing the same letter are not statistically significant at P < 0.05. Values in parenthesis show percent relative increase (+) or decrease (−) over the related controls.