Modulating response of sunflower (Hellianthus annuus) to induced salinity stress through application of engineered urea functionalized hydroxyapatite nanoparticles.

Agro-nanotechnology aims to improve the quality and quantity of plants and plant products while preserving environmental health. Contemporary anecdotal studies that provide representation of the use of nanostructures as fertilizers, pesticides, and plant growth regulators have highlighted the need to determine the effect of such modified nanofertilizers on transforming plant yield under abiotic stress. Present study was performed to modulate the physiological response of Hellianthus annuus through the application of Urea capped hydroxyapatite nanoparticles (Urea-HANPs) in stressed environment. Hydroxyapatite nanoparticles were synthesized via co-precipitation method, functionalized with urea and characterized through a series of contemporary techniques of transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. We observed that Urea-HANPs significantly (p < .05) ameliorated resistivity in plant to osmotic stress by enhancing agronomic and physiobiochemical attributes. Elevated chlorophyll contents were reported from tested leaves treated with Urea-HANPs in T6 (0.05 M NaCl + 10 μg/ml Urea-HANP) under induced salinity stress. Data revealed significant decrease in osmolytes at T3 (0.1 M NaCl), and T4 (0.2 M NaCl) which was significantly ameliorated in T9 (0.1 M NaCl + 10 μg/ml Urea-HANPs) and T12 (0.2 M NaCl + 10 μg/ml Urea-HANPs). The antioxidant system was boosted up by the application of Urea-HANPs preventing the plant from oxidative stress by scavenging reactive oxygen species (ROS). It has been concluded that alleviation in impact of osmotic stress on plant through the use of Urea-HANPs was coupled with elevation in photosynthetic performance, stimulation of osmolytes and boosting antioxidant system of plants.