The soil essays performed indicate the same behavior, but a general slower release trend when compared to citric acid solution (wt 2%) essays, this can be explained by hydroxyapatite (Ca10(PO4)6(OH)2) formation, that still an important source of calcium and phosphorus as a long-term slow release fertilizer. and Technological Development, grant 301743/2018-5), and CAPES (Coordination for the Improvement of Higher Education Personnel, Finance Code 001). The authors thank the Agronano Network , the Agroenergy Laboratory, and the National Nanotechnology Laboratory for Agribusiness (LNNA) for providing institutional support and facilities. was: sand (663 g kg-1), clay (303 g kg-1 clay) and silt (34 g kg-1). The others chemical and physical soil properties are presented bellow (Table ): Note: WHC = water holding capacity; OM = organic matter; SB = soil base saturation; CEC = cation exchange capacity; V% = percentage of soil base saturation.