| Summary: | The application of nanomaterials (NMs) in agriculture has become a global concern in recent years. However, studies on their effects on plants are still limited. Here, we conducted a seed germination experiment for 5 days and a hydroponics experiment for 14 days to study the effects of silicon dioxide NMs(nSiO<sub>2</sub>) and silicon carbide NMs(nSiC) (0,10, 50, 200 mg/L) on rice (<i>Oryza sativa</i> L.). Bulk SiO<sub>2</sub> (bSiO<sub>2</sub>) and sodium silicate (Na<sub>2</sub>SiO<sub>3</sub>) were used as controls. The results showed that nSiO<sub>2</sub> and nSiC increased the shoot length (11–37%, 6–25%) and root length (17–87%, 59–207%) of germinating seeds, respectively, compared with the control. Similarly, inter-root exposure to nSiO<sub>2</sub>, bSiO<sub>2,</sub> and nSiC improved the activity of aboveground catalase (10–55%, 31–34%, and 13–51%) and increased the content of trace elements magnesium, copper, and zinc, thus promoting the photosynthesis of rice. However, Na<sub>2</sub>SiO<sub>3</sub> at a concentration of 200 mg/L reduced the aboveground and root biomass of rice by 27–51% and 4–17%, respectively. This may be because excess silicon not only inhibited the activity of root antioxidant enzymes but also disrupted the balance of mineral elements. This finding provides a new basis for the effect of silica-based NMs promotion on seed germination and rice growth.
|
|---|