Enhancing Blackgram Yield: Validating a Soil Test-driven Fertilizer Prescription Equation for Alfisol

Abstract

Background: On-farm testing of fertilizer prescription equations is imperative to demonstrate the efficacy of technology implementation for the benefit of the stakeholders. The current research was conducted on a farmer’s holding, using blackgram (Vigna mungo L. Hepper), to evaluate the fertiliser prescription equations (FPEs) in the Thondamuthur block of Coimbatore district, Western Zone of Tamil Nadu. The treatments included control, blanket, blanket + FYM, Soil Test Crop Response (STCR) based fertilizer dose for an yield target of 1.0, 1.2 and 1.4 t ha-1, STCR-IPNS based fertilizer dose for an yield target of 1.0, 1.2 and 1.4 t ha-1 and farmer’s practice. Methods: Using the data of yield and fertilizer doses applied, parameters viz., per cent achievement, response ratio (RR), benefit: Cost ratio (BCR) were computed. Result: STCR-IPNS with a targeted yield of 1.4 t ha-1 consistently displayed the most substantial growth, superior yield and yield-related characteristics, with the per cent achievement falling within ±10 per cent variation. Furthermore, it exhibited a higher response ratio (RR) and a more favourable Benefit Cost Ratio (BCR) when compared to both farmer’s practice and blanket fertilizer recommendations. The results revealed that the target yield has been achieved within ±10 per cent variation proving the validity of the equations.