Ranjan Plant Physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Prayagraj, 211002, India.
Ranjan Plant Physiology and Biochemistry Laboratory, Department of Botany, University of Allahabad, Prayagraj, 211002, India.
Environ Pollut. 2022 Aug 15;307:119509. doi: 10.1016/j.envpol.2022.119509. Epub 2022 May 21.
The role of hydrogen sulfide (HS) is well known in the regulation of abiotic stress such as toxic heavy metal. However, mechanism(s) lying behind this amelioration are still poorly known. Consequently, the present study was focused on the regulation/mitigation of hexavalent chromium (Cr(VI) toxicity by the application of HS in wheat and rice seedlings. Cr(VI) induced accumulation of reactive oxygen species and caused protein oxidation which negatively affect the plant growth in both the cereal crops. We noticed that Cr(VI) toxicity reduced length of wheat and rice seedlings by 21% and 19%, respectively. These reductions in length of both the cereal crops were positively related with the down-regulation in the ascorbate-glutathione cycle, and were recovered by the application NaHS (a donor of HS). Though exposure of Cr(VI) slightly stimulated sulfur assimilation but addition of HS further caused enhancement in sulfur assimilation, suggesting its role in the HS-mediated Cr(VI) stress tolerance in studied cereal crops. Overall, the results revealed that HS renders Cr(VI) stress tolerance in wheat and rice seedlings by stimulating sulfur assimilation and ascorbate-glutathione which collectively reduce protein oxidation and thus, improved growth was observed.
硫化氢（HS）在调节非生物胁迫方面的作用，如有毒重金属，已经广为人知。然而，其背后的作用机制仍知之甚少。因此，本研究聚焦于 HS 在小麦和水稻幼苗中对六价铬（Cr(VI)毒性的调节/缓解作用。Cr(VI)诱导活性氧的积累，并导致蛋白质氧化，这对两种谷物作物的生长都有负面影响。我们注意到，Cr(VI)毒性使小麦和水稻幼苗的长度分别减少了 21%和 19%。这两种谷物作物长度的减少与抗坏血酸-谷胱甘肽循环的下调呈正相关，并通过施用 NaHS（HS 的供体）得到恢复。尽管 Cr(VI)的暴露轻微刺激了硫同化，但 HS 的添加进一步增强了硫同化，表明其在研究的谷类作物中 HS 介导的 Cr(VI)胁迫耐受中的作用。总的来说，这些结果表明，HS 通过刺激硫同化和抗坏血酸-谷胱甘肽来提高 Cr(VI)胁迫耐性，从而减少蛋白质氧化，从而观察到生长得到改善。
