Growing, physiological responses and Cd uptake of Corn (Zea mays L.) under different Cd supply

Figures & data

Table 1. Effects of Cd supply levels on the growth of corn.

Cd levels (μmol l^−1)	Plant height (mm)	Maximum root length (mm)	Fresh weight (g pot^−1)		Dry weight (g pot^−1)
			Shoot	Root	Shoot	Root
CK	60.2 ± 5.9	247.8 ± 10.2	3.47 ± 0.5	3.54 ± 0.4	0.23 ± 0.10	0.25 ± 0.09
12.5	60.2 ± 3.2	227.2 ± 38.9	4.16 ± 0.2	3.13 ± 0.6	0.27 ± 0.02	0.25 ± 0.03
25	63.3 ± 5.3	223.4 ± 23.7	4.57 ± 0.1	3.54 ± 0.1	0.28 ± 0.05	0.25 ± 0.03
50	61.7 ± 3.9	196.7 ± 40.8	4.22 ± 0.6	3.25 ± 0.3	0.27 ± 0.02	0.25 ± 0.01
100	62.1 ± 2.1	203.1 ± 26.8	4.36 ± 0.04	3.21 ± 0.2	0.28 ± 0.03	0.27 ± 0.06
200	54.1 ± 8.9	208.1 ± 14.7	3.45 ± 0.3	3.05 ± 0.3	0.24 ± 0.02	0.24 ± 0.02
400	52.5 ± 13.2	199.3 ± 15.4	2.77 ± 0.5	3.01 ± 0.2	0.21 ± 0.05	0.24 ± 0.02
800	51.2 ± 11.1	118.0 ± 28.3	2.35 ± 0.6	0.81 ± 0.5	0.20 ± 0.02	0.10 ± 0.05

Figure 1. Cadmium concentrations in the shoots and roots of corn grown at different Cd supply levels. Data with the same letter represent statistically identical values (p  0.05).

Figure 2. Cadmium uptake by shoots and roots of corn at different Cd supply levels. Data with the same letter represent statistically identical values (p   0.05).

Table 2. The transportation index (T_i) of Cd in plants grown for 21 days.

Cd concentration in solution (μmol l^−1)	0	12.5	25	50	100	200	400	800
Ti	0.41	0.54	0.74	0.77	0.78	0.71	1.14	1.08

Figure 3. Comparative cadmium bioconcentration factor (BCF) of plants were exposed at different cadmium supply level for 21 days.

Table 3. Effect of cadmium on leaf chlorophyll and carotenoid contents of corn at different cadmium supply level for 21 days.

Cd conc. in solution (μmol l^−1)	Chlorophyll a (mg 100 g^−1 FW)	Chlorophyll b (mg 100 g^−1 FW)	Chlorophyll a+b (mg 100 g^−1 FW)	Chlorophyll a/chlorophyll b	Carotenoid (mg 100 g^−1 FW)
0	84.91 ± 0.30a	110.14 ± 25.03a	195.06 ± 25.32a	0.80 ±  0.18	23.53 ± 0.33a
12.5	84.73 ± 6.34ab	72.65 ± 29.67b	157.38 ± 23.34ab	1.32 ± 0.59	22.37 ± 0.29a
25	80.35 ± 5.27ab	71.27 ± 10.40b	151.62 ± 14.48ab	1.14 ± 0.14	20.00 ± 0.45b
50	74.99 ± 20.19ab	69.23 ± 8.22b	144.21 ± 11.98b	1.12 ± 0.45	16.74 ± 1.88c
100	72.25 ± 2.48ab	60.94 ± 5.88b	133.19 ± 5.29b	1.19 ± 0.13	13.28 ± 0.58d
200	69.41 ± 24.37ab	56.98 ± 24.51b	126.39 ± 48.87bc	1.24 ± 0.09	12.85 ± 0.61d
400	58.72 ± 26.92bc	53.36 ± 0.97b	112.08 ± 27.53bc	1.10 ± 0.49	10.39 ± 0.79e
800	33.03 ± 5.49c	50.67 ± 30.46b	83.70 ± 32.34c	0.78 ± 0.36	6.99 ± 0.63f

Note: Results are means ± SD. Data in the same column followed by the same letter are not significantly different at 5% level of probability (Duncan’s multiple comparisons test).

Figure 4. Proline concentrations of corn under eight different cadmium pollution treatments. Values with the same superscript letters are not significantly different among treatments at p  0.05 according to Duncan’s multiple comparison tests.