Urea loaded hydroxyapatite nanocarrier for efficient delivery of plant nutrients in rice

Inappropriate use of phosphorus and nitrogen fertilizers has imposed irreparable damage to plant growth and productivity. Urea doped hydroxyapatite nanoparticles (Ur@HANP) was designed for controlled-release formulation for crop improvement. The main objective of the present work was to synthesize and evaluate the functioning of Ur@HANP on rice seed germination and transport of nano-nutrients in soil media. HANP was synthesized using sol–gel technique and urea was loaded into it for monitoring rice seeds’ physiological and biochemical activities under controlled laboratory condition. Seedling growth (5.99217 ± 0.156), fresh weight (13.8 ± 0.5) and dry weight (1.6 ± 0.5) were enhanced in Ur@HANP treatment compared to control. Both HANP and Ur@HANP was also tested in sand columns and agricultural soil to understand the retention capacity of plant nutrients in sand and interaction with soil colloids, where Ur@HANP showed almost twofold efficiency than conventional P and N fertilizers. Even at a higher dose of 1 M, it did not impart any kind of toxicity symptoms. Almost twofold increase in α-amylase and starch content in Ur@HANP could be the reason for such response. We anticipate Ur@HANP could be a suitable alternative for N and P fertilizers in the development of eco-friendly sustainable agriculture.