Efficacy of nano-silicon extracted from rice husk to modulate the physio-biochemical constituents of wheat for ameliorating drought tolerance without causing cytotoxicity

Abstract

Background: Abiotic stresses, like drought, are the major cause of shrinking plant, growth crop yields and quality. Nanotechnology has provided a significant improvement in increasing plant growth and yield of crops under stress conditions. This work assessed the potential of silicon for mitigating the negative effects of drought against wheat. In completely randomized design with three replicates, wheat seedlings grown under three watering levels (100, 60 and 40% of water holding capacity) were treated by silicon dioxide (SiO<inf>2</inf>) as a normal or bulk form (Si) and SiO<inf>2</inf> nanoparticles (SiNPs) with concentrations of 100 and 200 mg L⁻¹. SiNPs was extracted from rice husk. Results: Si and SiNPs treatments are shown to improve the growth of plants and increase the shoots and root weight, relative water content, photosynthetic pigments, and proline in wheat. SiO<inf>2</inf> either normal or nanoparticles at 100 mg L⁻¹ decreased lipid peroxidation as malondialdehyde was reduced. Also, nano-silicon increased free amino acids, antioxidant enzymes while decreased soluble sugars. Cytotoxicity assay proved the safety of nano-silicon usage. Conclusions: In conclusion, the present study documented the significance of rice husk-extracted nano-silicon at rate of 100 mg L⁻¹ for improving growth and increasing tolerance to drought in wheat grown under water deficit.