Jalil Sanaullah, Alghanem Suliman M S, Al-Huqail Arwa Abdulkreem, Nazir Muhammad Mudassir, Zulfiqar Faisal, Ahmed Temoor, Ali Sharafat, H A Abeed Amany, Siddique Kadambot H M, Jin Xiaoli
The Advanced Seed Institute, The Key Laboratory for Crop Germplasm Resource of Zhejiang Province, Zhejiang University, Hangzhou, 310058, China.
Biology Department, College of Science, Qassim University, Burydah, 52571, Saudi Arabia.
Chemosphere. 2023 Oct;338:139566. doi: 10.1016/j.chemosphere.2023.139566. Epub 2023 Jul 18.
Zinc oxide nanoparticles (nZn) have emerged as vital agents in combating arsenic (As) stress in plants. However, their role in mitigation of As induced oxidative stress is less studied. Therefore, this study aimed to assess the comparative role of nZn and ZnO in alleviating As toxicity in rice genotype "9311". The results of this study revealed that nZn demonstrated superior efficacy compared to ZnO in mitigating As toxicity. This superiority can be attributed to the unique size and structure of nZn, which enhances its ability to alleviate As toxicity. Exposure to As at a concentration of 25 μM L led to significant reductions in shoot length, root length, shoot dry weight, and root dry weight by 39%, 51%, 30%, and 46%, respectively, while the accumulation of essential nutrients such as magnesium (Mg), potassium (K), iron (Fe), manganese (Mn), and zinc (Zn) decreased by 25%-47% compared to the control plants. Additionally, As exposure resulted in stomatal closure and structural damage to vital cellular components such as grana thylakoids (GT), starch granules (SG), and the nucleolus. However, the application of nZn at a concentration of 30 mg L exhibited significant alleviation of As toxicity, resulting in a reduction of As accumulation by 54% in shoots and 62% in roots of rice seedlings. Furthermore, nZn demonstrated the ability to scavenge reactive oxygen species (ROS) like hydrogen peroxide (HO) and superoxide anion (O), while significantly promoted the gas exchange parameters, chlorophyll content (SPAD value), fluorescence efficiency (Fv/m) and antioxidant enzyme activities under As-induced stress. These findings highlight the potential of nZn in mitigating the adverse impacts of As contamination in rice plants. However, further research is necessary to fully comprehend the underlying mechanisms responsible for the protective effects of nZn and to determine the optimal conditions for their application in real-world agricultural settings.
氧化锌纳米颗粒（nZn）已成为对抗植物砷（As）胁迫的重要因子。然而，它们在减轻As诱导的氧化应激中的作用研究较少。因此，本研究旨在评估nZn和ZnO在缓解水稻基因型“9311”中As毒性方面的比较作用。本研究结果表明，在减轻As毒性方面，nZn比ZnO表现出更优异的效果。这种优越性可归因于nZn独特的尺寸和结构，这增强了其减轻As毒性的能力。暴露于浓度为25 μM L的As会导致地上部长度、根长度、地上部干重和根干重分别显著降低39%、51%、30%和46%，而与对照植物相比，镁（Mg）、钾（K）、铁（Fe）、锰（Mn）和锌（Zn）等必需营养元素的积累减少了25%-47%。此外，As暴露导致气孔关闭，并对诸如基粒类囊体（GT）、淀粉粒（SG）和核仁等重要细胞成分造成结构损伤。然而，施用浓度为30 mg L的nZn可显著减轻As毒性，使水稻幼苗地上部的As积累减少54%，根部减少62%。此外，nZn表现出清除过氧化氢（HO）和超氧阴离子（O）等活性氧（ROS）的能力，同时在As诱导的胁迫下显著促进气体交换参数、叶绿素含量（SPAD值）、荧光效率（Fv/m）和抗氧化酶活性。这些发现凸显了nZn在减轻水稻植株中As污染不利影响方面的潜力。然而，有必要进行进一步研究以全面理解nZn保护作用的潜在机制，并确定其在实际农业环境中应用的最佳条件。
