Impact of Titanium Oxide Nanoparticles on Growth, Pigment Content, Membrane Stability, DNA Damage, and Stress-Related Gene Expression in <i>Vicia faba</i> under Saline Conditions

Abstract

This study investigates the effects of titanium dioxide nanoparticles (nTiO2) on Vicia faba under salinity stress. Plants were treated with either 10 or 20 ppm nTiO2 and subjected to two different concentrations of salinity (100 and 200 mM NaCl) as well as the combined effect of nanoparticles and salinity. Salinity induced a reduction in dry weight, increased electron leakage and MDA content, increased chromosomal aberrations and DNA damage, and reduced transcript levels of some stress- and growth-related genes. nTiO2 treatment increased dry weight in unstressed plants and mitigated the salinity-damaging effect in stressed plants. nTiO2 application improved cell division, decreased chromosomal aberrations, and reduced DNA damage in plants under saline conditions. The upregulation of antioxidant genes further supports the protective role of nTiO2 against oxidative stress. Particularly significant was the ability of nTiO2 to enhance the upregulation of heat shock protein (HSP) genes. These findings underscore the potential of nTiO2 to reduce the osmotic and toxic effects of salinity-induced stress in plants.

Keywords

• nanotitanium dioxide
• salinity
• chromosomal aberration
• comet assay
• antioxidant-encoding genes
• heat shock proteins