Effects of silica nanoparticles on peas and other plants exposed to environmental stressors: a mini review

The growth and development of plants are constantly affected by many abiotic environmental factors such as temperature, light, humidity, mineral substances, carbon dioxide content, or ozone. Furthermore, with climate change, the impact of drought is becoming one of the main factors reducing plant productivity. In this study, the impact of silica nanoparticles (SiO₂ NPs) has been reviewed through the adverse effects of abiotic stress on plants' growth, oxidative stress, and antioxidative response. This paper discusses the impact of SiO₂ NPs on pea, barley, sweet pepper, wheat, strawberries, rice, potatoes, marigolds, and wheat adversely affected by drought, heavy metals, UV-B, and salinity. In the published studies we have reviewed, plants were all treated with SiO₂ or Si NPs. 20-30 nm particles in size with concentrations ranging from 10 to 125 ppm are most commonly reported. In addition, it was reported that spraying or watering of SiO₂ can increase plant tolerance to environmental stresses by increasing the activity of antioxidant enzymes, including catalase, ascorbate peroxidase, glutathione reductase, and superoxide dismutase, as well as reducing hydrogen peroxide and lipid peroxidation in plant tissue. Furthermore, the increase in total phenolic compounds and non-enzymatic antioxidant activity (DPPH, ABTS, FRAP) in plants treated with SiO₂ NPs under different stressors were also discussed. Thus, the reviewed publications support the positive role of SiO₂ NPs application, especially the decisive role of 20-30 nm SiO₂, in managing the detrimental effects of environmental stress on different plants.