<p>In this study, we used silicon (Si, in the form of K<sub>2</sub>SiO<sub>3</sub>, 2 mM) to alleviate the toxicity of aluminum oxide (Al<sub>2</sub>O<sub>3</sub>) nanoparticles (NPs) in barley (<em>Hordeum vulgare</em> L.). Using Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) analyses, we showed that the Al<sub>2</sub>O<sub>3</sub> NPs were taken up by barley plants. Barley growth was negatively affected by the addition of 3 g l<sup>-1</sup> nano-Al<sub>2</sub>O<sub>3</sub>, whereas the diminishing effect of NPs on barley growth was not obvious when 1 g l<sup>-1</sup> nano-Al<sub>2</sub>O<sub>3</sub> was applied, indicating that the nano-Al<sub>2</sub>O<sub>3</sub> action is dependent on nano-Al<sub>2</sub>O<sub>3</sub> dose. Si pretreatment ameliorated toxic effects of high nano-Al<sub>2</sub>O<sub>3</sub> on root growth. Si pretreatment did not decrease nano-Al<sub>2</sub>O<sub>3</sub> entry into roots but reduced nano-Al<sub>2</sub>O<sub>3</sub> accumulation in the shoot. The restriction of the root-to-shoot translocation of nano-Al<sub>2</sub>O<sub>3 </sub>was one of the important mechanisms for Si to mitigate high nano-Al<sub>2</sub>O<sub>3</sub> toxicity. The occurrence of oxidative stress was found under 3 g l<sup>1</sup> nano-Al<sub>2</sub>O<sub>3 </sub>treatment, as evaluated by the accumulation of malondialdehyde (MDA). Exogenous addition of Si could alleviate toxicity symptoms induced by Al<sub>2</sub>O<sub>3</sub> nanoparticles by reducing lipid peroxidation via enhancing antioxidant activity of catalase as well as by limiting the root-to-shoot translocation of nano-Al<sub>2</sub>O<sub>3</sub>. These data provide the first direct evidence that the Si pretreatment ameliorates nano Al<sub>2</sub>O<sub>3</sub> phytotoxicity in plants.</p>
Potential Role of Plants Hordeum vulgare L. and Panax ginseng L. in Resolving the Fertility Disorders and Stress-Induced Oxidative Stress Arises from Hypothyroidism in Adult Female Rats
