Department of Botany, Govt. MVM College, Barkatullah University Bhopal, M.P, 462004, India.
Botany and Microbiology Department, King Saud University, Riyadh, 11451, Saudi Arabia.
Plant Physiol Biochem. 2022 Oct 1;188:1-11. doi: 10.1016/j.plaphy.2022.07.026. Epub 2022 Jul 31.
The contamination of agricultural soils with Arsenic (As) is a significant environmental stress that restricts plant growth, metabolism, and productivity worldwide. The present study examined the role of elemental sulfur (S) in protecting Brassica napus plants from Arsenic (As) toxicity. Arsenic (100, and 200 mg As kg soil) in soil caused detrimental effects on five Brassica napus cultivars (Neelam, Teri-Uttam Jawahar, Him Sarson, GSC-101, and NUDB 26-11). The As toxicity inhibited the growth and photosynthesis indices in all cultivars with more deterioration effects in NUDB 26-11. Plant absorption and uptake of As caused the generation of oxidative injury by accumulating the reactive oxygen species (ROS), which simultaneously decreased the plant defence capability and ultimately the photosynthesis. Application of sulfur (S, 100 or 200 mg S kg soil) alleviated the negative impacts and toxicity of As on the photosynthesis and growth matrices of plants, especially under high S level. S also boosted the antioxidant potential of plants and toned-down lipid peroxidation and ROS aggravation such as superoxide anion (O) and HO, hydrogen peroxide, in As affected plants. In general, S at 200 mg kg soil more perceptibly increased the functionality of antioxidant enzymes, and non-enzymatic antioxidants, metal chelators and non-protein thiols. Further amendment of soil with S at fifteen days before seed sowing affected by As-induced toxic effects (added to soil at the time of sowing) considerably intensified the endogenous hydrogen sulfide (HS) content and its regenerating enzymes D-cysteine desulfhydrase (DCD) and L-cysteine desulfhydrase (LCD) that further strengthened the defense capability of plants to withstand As-stress. Our results suggest the role of HS in the S-induced defense operation of the B. napus plants in restraining As toxicity. The current study shows that S as a source of S might be used to promote the growth of B. napus plants in polluted agricultural soils.
砷（As）污染农业土壤是一种严重的环境胁迫，限制了全球植物的生长、代谢和生产力。本研究探讨了元素硫（S）在保护油菜（Brassica napus）植物免受砷（As）毒性方面的作用。土壤中 100 和 200 mg As kg 土壤的砷（As）对五个油菜（Brassica napus）品种（Neelam、Teri-Uttam Jawahar、Him Sarson、GSC-101 和 NUDB 26-11）造成了有害影响。As 毒性抑制了所有品种的生长和光合作用指标，其中 NUDB 26-11 的恶化效果更为明显。植物对 As 的吸收和摄取导致活性氧（ROS）的积累，从而产生氧化损伤，同时降低了植物的防御能力，最终影响了光合作用。硫（S，100 或 200 mg S kg 土壤）的应用缓解了 As 对植物光合作用和生长基质的负面影响和毒性，尤其是在高 S 水平下。S 还增强了植物的抗氧化能力，减轻了脂质过氧化和 ROS 加剧，如超氧阴离子（O）和 HO、过氧化氢在受 As 影响的植物中。总的来说，S 在 200 mg kg 土壤下更明显地增加了抗氧化酶、非酶抗氧化剂、金属螯合剂和非蛋白巯基的功能。在种子播种前 15 天向受 As 诱导的毒性影响的土壤中进一步添加 S（播种时添加到土壤中），显著增加了内源性硫化氢（HS）含量及其再生酶 D-半胱氨酸脱巯酶（DCD）和 L-半胱氨酸脱巯酶（LCD），进一步增强了植物抵御 As 胁迫的防御能力。我们的结果表明 HS 在油菜（Brassica napus）植物的 S 诱导防御机制中起作用，以抑制 As 毒性。本研究表明，S 作为 S 的来源，可以用于促进受污染农业土壤中油菜（Brassica napus）植物的生长。
