Nomani L, Zehra A, Choudhary S, Wani K I, Naeem M, Siddiqui M H, Khan M M A, Aftab T
Department of Botany, Aligarh Muslim University, Aligarh, India.
Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia.
Plant Biol (Stuttg). 2022 Jun;24(4):642-651. doi: 10.1111/plb.13242. Epub 2021 Mar 7.
A supply of plant micronutrients (some of which are metals) is necessary to regulate many plant processes; their excess, however, can have detrimental consequences and can hamper plant growth, physiology and metabolism. Artemisia annua is an important crop plant used in the treatment of malaria. In this investigation, the physio-biochemical mechanisms involved in exogenous hydrogen sulphide-mediated (H S) alleviation of copper (Cu) stress in A. annua were assessed.. Two different levels of Cu (20, 40 mg·kg ), one H S treatment (200 µm) and their combinations were introduced while one set of plants was retained as control. Results showed that the presence of excess Cu in the soil reduced growth and biomass, photosynthetic parameters, chlorophyll content and fluorescence, gas exchange parameters and induced antioxidant enzyme activity. Copper stress enhanced the production of thiobarbituric acid reactive substances (TBARS) and increased Cu content in both roots and shoots of affected plants. Exogenous application of H S restored the physio-biochemical characteristics of Cu-treated A. annua plants by reducing lipid peroxidation and enhancing the activity of antioxidant enzymes in Cu-stressed plants as compared with the controls. Hydrogen sulphide also reduced the Cu content in different plant parts, increased photosynthetic efficiency, trichome density, average area of trichomes and artemisinin content. Therefore, our results provide a comprehensive assessment of the defensive role of H S in Cu-stressed A. annua.
供应植物微量营养素（其中一些是金属）对于调节许多植物过程是必要的；然而，它们的过量可能会产生有害后果，并可能阻碍植物生长、生理和新陈代谢。青蒿是一种用于治疗疟疾的重要作物。在本研究中，评估了外源硫化氢（H₂S）介导的青蒿铜（Cu）胁迫缓解过程中涉及的生理生化机制。引入了两种不同水平的铜（20、40 mg·kg⁻¹）、一种H₂S处理（200 µm）及其组合，同时保留一组植物作为对照。结果表明，土壤中过量铜的存在降低了生长和生物量、光合参数、叶绿素含量和荧光、气体交换参数，并诱导了抗氧化酶活性。铜胁迫增强了硫代巴比妥酸反应性物质（TBARS）的产生，并增加了受影响植物根和地上部的铜含量。与对照相比，外源施用H₂S通过降低脂质过氧化和增强铜胁迫植物中抗氧化酶的活性，恢复了铜处理的青蒿植物的生理生化特征。硫化氢还降低了不同植物部位的铜含量，提高了光合效率、毛状体密度、毛状体平均面积和青蒿素含量。因此，我们的结果全面评估了H₂S在铜胁迫青蒿中的防御作用。
