Asian Journal of Soil Science and Plant Nutrition

An integrated nutrient stick, a solid, compact fertilizer formulation is designed to supply essential plant nutrients in a slow and controlled manner. It is prepared in the form of a stick and placed directly into the soil near the plant root zone, where it gradually dissolves and releases nutrients over time. Nutrient sticks help improve nutrient use efficiency, reduce nutrient losses, and ensure a steady nutrient supply for plant growth and development. However, the rate of nutrient release from the integrated nutrient stick in different soils is ambiguous. The experiment was carried out for a period of 60 days in red sandy loam soil collected from the Kasaragod district of Kerala to elucidate the release of nutrients from a newly formulated solid integrated nutrient sticks and their contribution for improvement of soil health.  An integrated nutrient stick was developed by the process of mixing of both organic and inorganic raw materials at appropriate proportions. The design of the study was Completely Randomized Design (CRD) with five treatments were imposed in the trials: T_{1 –} Recommended dose of fertilizer according to the Kerala Agricultural University package of practices (ginger); T₂ - nutrient stick (inorganic raw materials only), T₃ - Integrated nutrient stick @ 1:1 (Organic: inorganic raw materials); T₄ - Integrated nutrient stick @ 1:1.5 (Organic: inorganic raw materials); T₅ - Integrated nutrient stick @ 1.5:1 (Organic: inorganic raw materials). The incubation study revealed that the high content of available nitrogen was recorded for T₄ (organic: inorganic in 1:1.5) at 30 days after incubation (358 kg/ha) followed by a decline, and release was constant till the end of the incubation study, whereas the release was sustained and gradual at 60th day (321.03 kg/ha) for T₅. Similarly, an improved available primary, secondary and micro nutrient contents were observed with respect to Integrated nutrient stick application (T₄ and T₅ mainly) which registered maximum availability of nutrients such as phosphorus (238.05 kg/ha), potassium (201.20 kg/ha), sulphur (145 mg/kg), calcium (450 mg/kg), magnesium (166 mg/kg), and micro nutrients compared to Control (KAU fertilizer recommendation). Integrated nutrient stick application also exhibited beneficial effects with respect to physical properties such as bulk density and maximum water holding capacity of study soil. Nutritional enhancement through an integrated nutrient stick could be a low-cost but high-efficiency solution compared to non-blended fertilizers.