Mechanized establishment and integrated nutrient management drive productivity, profitability, and energy efficiency in rice–groundnut cropping systems

Rice–groundnut cropping systems are widely practiced in coastal regions of Eastern India due to their potential for enhancing system productivity and profitability. However, the sustainability of these systems is increasingly challenged by inappropriate establishment methods, imbalanced nutrient management, and declining soil health. A field experiment was conducted during the wet and dry seasons of 2022–23 and 2023–24 at the Central Farm of Regional Research & Technology Transfer Station (RRTTS), Coastal Zone, OUAT, Bhubaneswar to study the effect of establishment methods and nutrient management practices on the growth, yield, nutrient dynamics, and economics of rice-groundnut cropping system. The experiment was performed in strip plot design with sixteen treatment combinations, which were replicated thrice. The design consisted of four types of establishment methods (viz., direct seeded rice (DSR), puddled manual transplanted rice (PTR), puddled machine transplanted rice (PMTR) and non- puddled machine transplanted rice (NMTR)) allocated to the main plot and four nutrient management practices (Soil test-based fertilizer recommendation (STBFR), Nutrient recommendation by Rice Crop Manager (RCM), 75% STBFR + farm yard manure and 75% STBFR + in situ green manuring with dhaincha) allocated to the subplot in wet season for rice. In dry season, STBFR + Rhizobium + Phosphate-solubilizing bacteria (PSB) was applied to groundnut in all the plots. PMTR recorded the highest rice equivalent yield (REY) of 11166 kg ha -1 which was at par with NMTR (11140 kg ha -1 ). Among the integrated nutrient management practices, 75% STBFR + GM achieved the highest pooled REY (11,363 kg ha −1 ). The 75% STBFR + GM practice recorded the highest system NPK uptake (211.62, 35.55, and 193.98 kg ha −1 , respectively), enhancing the system N uptake by 4.35, 5.78 and 18.23%, P uptake by 1.25, 5.08 and 19.21%, and K uptake by 2.08, 5.16 and 15.67% over RCM, 75% STBFR + FYM and 100% STBFR, respectively. Among the establishment methods, PMTR recorded the highest system NPK uptake (204.95, 35.96, and 192.32 kg ha −1 , respectively). Application of 75% STBFR + GM gave the the most promising results, recording the highest benefit cost ratio (1.88) and energy ratio (8.60). Correlation and principal component analysis revealed strong positive associations between rice equivalent yield and nitrogen, phosphorus, and potassium uptake, indicating that system productivity was primarily driven by improved nutrient acquisition. The application of 75% STBFR + GM in PMTR sustained productivity and sustainability in rice-groundnut by enhancing soil quality in Eastern India.