Hydroxyapatite Nanoparticles as an Ef fective Fertilizer in Sunflower Crop Quality

Abstract

Nanotechnology involves manipulating materials at the atomic or molecular scale, particularly those smaller than 100 nm, which display unique properties due to quantum ef fects and a high surface area-to-volume ratio. In agriculture, nanoparticles (NPs) enhance fertilizer and pesticide ef ficiency, improve crop yield, and enable early detection and treatment of plant diseases. This study evaluated the ef fect of hydroxyapatite nanoparticles (HANPs) as a foliar fertilizer on sunflower (Helianthus annuus) crop quality, alongside vermicompost, chemical fertilizer, and biofertilizer applied to soil. The HANPs ranged from 10 to 45 nm, with 53.1% between 15 and
25 nm, predominantly rod-shaped. Agronomic variables (plant height, stem and disc diameter) and phytochemical properties of sunflower oil (total phenolic compounds, flavonoid content, antioxidant capacity) were analyzed under three HANP doses: 2000, 4000, and 6000 mg L-1. Results showed that vermicompost and chemical fertilizer had no significant dif ferences in plant height, whereas biofertilizer
(299.6 and 258.6 cm) dif fered significantly from the control. Phytochemical analyses yielded 17.9-35.4 mg GAE mL-1 of phenolic compounds, 29.8-60.7 mg QE mL-1 of flavonoids, and 18024.60-25159.52 μM TE mL-1 of antioxidant activity across treatments. The aim was to assess HANPs’ influence on sunflower development and the antioxidant profile of its oil. Among the doses tested, 4000 mg L-1 proved optimal for enhancing total phenolic and flavonoid content, as well as antioxidant capacity, indicating its potential for improving the nutritional and functional quality of sunflower oil.