Positive Impact of Green Synthesized Silica Nanoparticles in Plant Growth Promotion and Physiological Responses of Eruca sativa Mill.

Agricultural crops are an essential base component of all ecosystems. Nanotechnology applications in plants growth and crop protection are necessary to the agriculture sector in long-term viability. Silica nanoparticles (SiO₂ NPs) have demonstrated a wide range of application in a variety of technological domains, due to their distinctive properties such as bioactivity, stability, customizable porosity. The green synthesis of SiO₂ NPs and their significant application would be a novel approach towards agriculture sector for plant growth and development. This study investigated the effects of different concentrations (100, 250, 500 & 1000 mg kg^-1) of agro-waste mediated nano-sized SiO₂ NPs on plant growth characteristics, biochemical such as total protein, chlorophyll content and anti-oxidants in Eruca sativa seedlings under controlled conditions. The phenolic and flavonoid components, as well as the fatty acids of E. sativa, were quantified using high-performance liquid chromatography (HPLC), gas chromatography mass spectrometry (GC-MS) and liquid chromatography mass spectrometry (LC-MS). Scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) were used to measure the accumulation of SiO₂ NPs in plant tissue. The results showed that using SiO₂ NPs at a concentration of 500 mg kg^-1 enhanced the growth parameters i.e. root and shoot length 4.9 & 4.7 cm respectively compared to control and physiological properties (chlorophyll content and antioxidants) of the E. sativa plant more than the control group. The phenolic and flavonoid contents were also increased after the exposure of SiO₂ NPs. Exogenous administration of SiO₂ NPs at optimum concentrations can thus have a beneficial effect on E. sativa seedlings, aiding in crop sustainability by offering an alternate supply of silica fertilizers.