Toxicity Assessment of SiO 2 Nanoparticles to Pear Seedlings

To date, the effects of nanoparticles on woody plants remain unaddressed. This study reveals some of the physiological and biochemical effects of SiO2 nanoparticles on wild pear seedlings. The seedlings were irrigated with different concentrations of nano silica (0, 10, 100, 500 and 1000 mg/l) for 14 days. Nanoparticle adsorption and absorption, biomass allocation, gas exchange, relative water content, xylem water potential, electrolyte leakage, pigment and proline content, antioxidant enzymes, and nutrient cycles were surveyed. The attachment of nanoparticles on the root surface was observed by scanning electron microscopic and the accumulation of Si in leaves was measured by X-ray fluorescence analysis. Although the performed experiments did not show any acute toxic effects of adding of SiO2 nanoparticles in irrigation to wild pear plant, the finding should be confirmed with other experiments of longer duration and high exposure concentrations before a final conclusion in this issue can be made.