Salinity stress is a major limitation on global agricultural productivity, impairing plant growth, photosynthesis, ion balance, and yield through osmotic stress, ionic toxicity, and excessive accumulation of reactive oxygen species. In this context, silicon dioxide nanoparticles (SiO₂-NPs) have emerged as a promising strategy to enhance plant tolerance to saline conditions. This study investigates the effects of seed priming with SiO₂-NPs on salinity stress tolerance in cucumber ( Cucumis sativus L.) plants and elucidates the associated physiological and biochemical mechanisms. The results indicate that seed priming with SiO₂-NPs at an optimal concentration of 50 ppm markedly improves cucumber plant performance under salt stress by promoting growth, preserving photosynthetic efficiency, and enhancing antioxidant capacity. Seed priming with SiO₂-NPs also contributes to improved osmotic adjustment by regulating proline metabolism, thereby supporting cellular homeostasis under saline conditions. In addition, primed plants exhibit enhanced ion exclusion and selective ion uptake, which reduces the detrimental accumulation of toxic ions and maintains nutrient balance. These protective effects are further associated with improved cucumber fruit quality under salinity stress, highlighting the agronomic relevance of this nanotechnological approach. Overall, the findings revealed that seed priming with SiO₂-NPs can mitigate salinity-induced damage through coordinated regulation of growth, photosynthesis, antioxidant defense, proline homeostasis, and ion transport. This study highlights the potential of seed priming with SiO₂-NPs in cucumber as an effective tool for improving crop resilience and productivity in saline environments and offers valuable insights for their sustainable use in climate-resilient agriculture.
Khan et al. (Mon,) studied this question.