Table 2. Effects of NaHS on the levels of chlorophyll (Chl) a, b, total Chl, carotenoids, water soluble proteins, relative water content (RWC) and proline (Pro) in rice plants with or without Cd stress.
| Treatments | Chl a (mg g−1 FW) | Chl b (mg g−1 FW) | Total Chl (mg g−1 FW) | Carotenoids (mg g−1 FW) | Water-soluble proteins (mg g−1FW) | RWC (%) | Pro (μmol g−1FW) |
|---|---|---|---|---|---|---|---|
| Control | 2.75 ± 0.13cd | 0.858 ± 0.14f | 3.61 ± 0.19e | 0.713 ± 0.02d | 21.26 ± 1.16e | 98.24 ± 0.31e | 0.152 ± 0.02a |
| H2S | 2.96 ± 0.09d | 0.841 ± 0.07f | 3.81 ± 0.17f | 0.722 ± 0.03d | 21.72 ± 1.48e | 97.84 ± 0.43e | 0.176 ± 0.01ab |
| H2S + HT | 2.80 ± 0.14d | 0.856 ± 0.05f | 3.66 ± 0.14e | 0.709 ± 0.01d | 19.84 ± 1.66d | 98.16 ± 0.17e | 0.149 ± 0.02a |
| Cd1 | 2.31 ± 0.27b | 0.686 ± 0.05c | 3.00 ± 0.28c | 0.553 ± 0.06b | 18.38 ± 0.89cd | 81.05 ± 0.72b | 0.239 ± 0.01c |
| H2S + Cd1 | 2.67 ± 0.09c | 0.785 ± 0.03e | 3.45 ± 0.11d | 0.714 ± 0.08d | 19.46 ± 1.14d | 94.45 ± 1.06d | 0.214 ± 0.01bc |
| Cd2 | 1.50 ± 0.14a | 0.490 ± 0.08a | 1.99 ± 0.18a | 0.481 ± 0.06a | 14.30 ± 0.40a | 72.49 ± 1.67a | 1.319 ± 0.17f |
| H2S + Cd2 | 2.24 ± 0.25b | 0.645 ± 0.07d | 2.88 ± 0.32c | 0.663 ± 0.08c | 17.02 ± 0.93bc | 86.26 ± 0.82c | 0.355 ± 0.06d |
| H2S + HT + Cd2 | 1.57 ± 0.08a | 0.499 ± 0.08b | 2.07 ± 0.16b | 0.499 ± 0.03a | 16.18 ± 0.98b | 73.05 ± 2.47a | 0.921 ± 0.08e |
Control, H2S, H2S + HT, Cd1, H2S + Cd1, Cd2, H2S + Cd2, and H2S + HT + Cd2 correspond to the group of seedlings exposed to only nutrients, 100 μM NaHS, 100 μM NaHS + 200 μM hypotaurine, 250 μM CdCl2, 100 μM NaHS + 250 μM CdCl2, 500 μM CdCl2, 100 μM NaHS + 500 μM CdCl2 and 100 μM NaHS + 200 μM hypotaurine + 500 μM CdCl2, respectively. Values are means ± SD of three independent replications (n = 3). Different subscripted letters (a, b, c, d, e and f) within the column indicate statistically significant differences among the treatments according to Duncan’s multiple range test (P < 0.05). FW, fresh weight.