Enhancing agricultural sustainability through the combined use of bio-slurry and chemical fertilizers: Insights from field trials in pea and radish

Abstract

Biogas slurry (BS), a by-product of anaerobic digestion, is rich in nutrients and holds promise as a sustainable alternative to chemical fertilizers. This study evaluated the effects of BS, chemical fertilizer nitrogen (CFN), and their combination (1, 1) on the growth and yield of Pisum sativum (pea) and Raphanus sativus (radish). The combined treatment (½ CFN + ½ BSN) produced the highest yields for both crops—12.48 t·ha⁻¹ for peas and 17.3 t·ha⁻¹ for radish—significantly surpassing control treatments. In peas, the highest grain nitrogen content (2.2 %) occurred under the combined treatment, while CFN and BSN resulted in the highest phosphorus (0.17 %) and potassium (2.09 %) contents, respectively. Radish plants also showed maximum N, P, and K concentrations in shoots and roots under the combined treatment. Economic analysis revealed that the integrated application of CFN and BSN treatment had the highest profitability, with a value-cost ratio of 16.0 for peas and 9.7 for radish. These results suggest that integrating BS with CFN can enhance crop productivity, improve nutrient uptake, and reduce reliance on synthetic fertilizers, contributing to more sustainable agricultural practices.