A Comparative Study of Fertilizer Recommendations to Optimize Groundnut Yield in Southern Karnataka

A field experiment was conducted during kharif 2022 in Bengaluru rural district, Karnataka, to validate soil test crop response (STCR) based fertilizer prescriptions for groundnut on Alfisols. The study utilized a randomized complete block design with seven treatments, including STCR targets (30 and 25 q ha-1) through inorganic and integrated approaches, General Recommended Dose (GRD), Soil Test Laboratory approach (STL/LMH), and an absolute control. The soil was sandy loam, acidic(pH5.68), with medium available nitrogen and potassium, and high phosphorus. STCR fertilizer prescription equations developed for Zone¿5 were used. Results showed significantly higher pod yield with the STCR integrated approach for a 30q ha-1 target (30.19 q ha-1), surpassing other treatments. STCR inorganic approach for 30 q ha-1 and 25 q ha-1 targets yielded 30.02 q ha-1 and 25.17 q ha-1 respectively, while the integrated approach for 25 q ha-1 target yielded 25.94 q ha-1. These were superior to GRD (20.18 q ha-1) and STL / LMH (20.56 qha-1). Nutrient uptake (N, P, K) was significantly higher in STCR-integrated treatments, attributed to improved soil properties and nutrient availability. The STCR integrated approach also demonstrated higher agronomic nitrogen (1.56 kg kg-1) and phosphorus (0.50kg kg-1) use efficiency. The per cent deviation was within ± 10% proving the validity of the developed targeted yield equations. This study concludes that STCR targeted yield equations are highly suitable for groundnut in Zone-5 of Karnataka, promoting higher yields and encouraging the use of farmyard manure for soil sustainability despite initial higher costs.

Pagina's: 42, Paperback, Eliva Press