1 research outputs found
Effect of Cerium Oxide Nanoparticles on Rice: A Study Involving the Antioxidant Defense System and In Vivo Fluorescence Imaging
Previous
studies have reported the uptake of cerium oxide nanoparticles
(<i>n</i>CeO<sub>2</sub>) by plants, but their physiological
impacts are not yet well understood. This research was aimed to study
the impact of <i>n</i>CeO<sub>2</sub> on the oxidative stress
and antioxidant defense system in germinating rice seeds. The seeds
were germinated for 10 days in <i>n</i>CeO<sub>2</sub> suspension
at 62.5, 125, 250, and 500 mg L<sup>–1</sup> concentrations.
The Ce uptake, growth performance, stress levels, membrane damage,
and antioxidant responses in seedlings were analyzed. Ce in tissues
increased with increased <i>n</i>CeO<sub>2</sub> concentrations,
but the seedlings showed no visible signs of toxicity. Biochemical
assays and in vivo imaging of H<sub>2</sub>O<sub>2</sub> revealed
that, relative to the control, the 62.5 and 125 mg <i>n</i>CeO<sub>2</sub> L<sup>–1</sup> treatments significantly reduced
the H<sub>2</sub>O<sub>2</sub> generation in both shoots and roots.
Enhanced electrolyte leakage and lipid peroxidation were found in
the shoots of seedlings grown at 500 mg <i>n</i>CeO<sub>2</sub> L<sup>–1</sup>. Altered enzyme activities and levels
of ascorbate and free thiols resulting in enhanced membrane damage
and photosynthetic stress in the shoots were observed at 500 mg <i>n</i>CeO<sub>2</sub> L<sup>–1</sup>. These findings demonstrate
a <i>n</i>CeO<sub>2</sub> concentration-dependent modification
of oxidative stress and antioxidant defense system in rice seedlings