Nutrient release pattern of organo-mineral fertilizers in Southern laterites of Kerala

The study was conducted at the Department of Agronomy, College of Agriculture, Vellayani, Kerala Agricultural University, during Rabi 2023-2024. It focused on formulating two organo-mineral fertilizers (OMF 1 and OMF 2) suited for Sesamum and evaluating its nutrient release patterns. The experiment utilized a completely randomized block design with four treatments and four replications for each treatment. The treatments were:- T1 (100% recommended dose of nutrients (RDN) as OMF 1), T2 (100% RDN as OMF 2), T3 (100% RDN as per Kerala Agricultural University Package of Practices, and T4 (Control). At 15 days after incubation (DAI), T3 (conventional fertilizer) demonstrated significantly higher nutrient release, with 89.99% of applied nitrogen, 80% of phosphorus, and 89.85% of potassium released. In contrast, OMF 1 and OMF 2 exhibited a slower nutrient release, with nitrogen release ranging from 53.18% to 53.22%, phosphorus from 45.65% to 50%, and potassium from 40.40% to 43.23%. At 30 days after incubation, nutrient release remained higher for T3. However, at 45, 60, 75, and 90 days after incubation, OMF 1 and OMF 2 outperformed T3, showing a more sustained and gradual release of nutrients over time. This study underscores the potential of organo-mineral fertilizers to provide a controlled and prolonged nutrient supply, enhancing nutrient use efficiency and supporting long-term soil fertility in sesamum cultivation.