Table 4. Effects of NaHS on the levels of non-enzymatic antioxidants ascorbic acid (AsA) and glutathione (GSH), as well as their redox states (AsA/DHA and GSH/GSSG) in rice plants with or without Cd stress.
| Treatments | AsA (nmol g−1FW) | DHA (nmol g−1FW) | AsA/DHA ratio | GSH (nmol g−1FW) | GSSG (nmolg−1FW) | GSH/GSSG ratio |
|---|---|---|---|---|---|---|
| Control | 4883.87 ± 480.77ef | 738.39 ± 42.88d | 6.60 ± 0.27c | 416.69 ± 32.55b | 33.06 ± 2.87c | 12.72 ± 2.10bc |
| H2S | 4974.19 ± 194.53f | 767.62 ± 75.33d | 6.48 ± 0.49c | 470.50 ± 30.07c | 34.31 ± 1.49c | 13.71 ± 0.32c |
| H2S + HT | 4824.72 ± 52.43e | 692.09 ± 52.40c | 7.15 ± 1.24d | 433.32 ± 16.49b | 37.07 ± 2.76d | 11.72 ± 0.71b |
| Cd1 | 3756.02 ± 180.91c | 601.18 ± 61.55b | 6.29 ± 0.55c | 580.29 ± 41.89d | 30.27 ± 2.90b | 19.39 ± 3.77d |
| H2S + Cd1 | 4593.66 ± 110.01d | 621.18 ± 67.45b | 7.47 ± 0.97d | 583.77 ± 9.51d | 22.91 ± 1.81a | 25.60 ± 2.25e |
| Cd2 | 2579.57 ± 202.56a | 866.13 ± 40.52e | 2.98 ± 0.11b | 281.48 ± 34.26a | 40.59 ± 2.36e | 6.98 ± 1.60a |
| H2S + Cd2 | 3563.66 ± 81.11b | 508.92 ± 53.84a | 7.04 ± 0.58d | 631.05 ± 35.43e | 22.47 ± 1.89a | 28.21 ± 2.68f |
| H2S + HT + Cd2 | 2493.32 ± 204.77a | 1032.89 ± 27.93f | 2.42 ± 0.26a | 259.04 ± 38.67a | 32.88 ± 2.35c | 7.92 ± 1.50a |
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-f) within the column indicate statistically significant differences among the treatments according to Duncan’s multiple range test (P < 0.05). FW, fresh weight; DHA, dehydroascorbic acid; GSSG, oxidized glutathione.