Cadmium-Induced Upregulation of Lipid Peroxidation and Reactive Oxygen Species Caused Physiological, Biochemical, and Ultrastructural Changes in Upland Cotton Seedlings

Table 2

Chlorophyll pigments and fluorescence of leaves of cotton seedlings grown under Cd stress.

Cd levels	Chlorophyll pigments			Chlorophyll fluorescence
	Chl a	Chl b	Chl a/b	𝐹𝑚	𝐹𝑚^′	𝐹𝑣/𝐹𝑚	NPQ; (𝐹𝑚/𝐹𝑚^′−1)
0 µM	0.044 ± 0.00^a; (0.00)	2.72 ± 0.13^a; (0.00)	0.016 ± 0.003^a; (0.00)	0.49 ± 0.05^a; (0.00)	0.49 ± 0.01^a; (0.00)	0.81 ± 0.02^a; (0.00)	0.03 ± 0.08^a; (0.00)
500 µM	0.021 ± 0.01^b; (−52.27)	2.22 ± 0.27^a; (−19.12)	0.011 ± 0.005^a; (−33.83)	0.33 ± 0.03^b; (−32.65)	0.34 ± 0.01^b; (−30.61)	0.65 ± 0.02^b; (−19.75)	0.05 ± 0.03^a; (55.17)

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.