Effect of supplementing biochar obtained from different wastes on biochemical and yield response of French bean (Phaseolus vulgaris L.): An experimental study

Abstract

This study investigates the utilization of selected agro-industrial wastes as feedstock for biochar production and subsequent cultivation of French bean (Phaseolus vulgaris L.). The biochar was analyzed using Scanning Electron Microscope (SEM-Zeiss) coupled with Energy Dispersive Spectroscopy (EDS) and Fourier Transform Infrared (FTIR) spectroscopy for structural, morphological, and elemental analysis. For this, French bean was grown using selected wastes such as horse manure biochar (HMB), rice husk biochar (RHB), algal residue biochar (ALB1 and ALB2), coal waste, and control treatments, without any amendment. The results showed that the maximum significant (p < 0.05) seedling germination (91.05 ± 1.30%), fresh biomass (8.90 ± 0.30 g), growth rate (1.27 ± 0.03 g/day), seedling length (13.20 ± 0.20 cm), root length (7.20 ± 0.32 cm), total chlorophyll content (4.56 ± 0.41 mg/g fwt.), plant height (43.63 ± 2.17 cm), number of leaves (27.00 ± 2.00), pod length (19.58 ± 3.17 cm), and pod yield/plant (65.32 ± 2.56 g) was observed using HMB treatment. The enzymatic activities such as catalase (CAT: 82.17 ± 3.20 μg/g), superoxide dismutase (SOD: 108.27 ± 3.10 μg/g), urease (6.10 ± 0.18 μg/g) and acid phosphatase (3.97 ± 0.03 μg/g) were also recorded highest using HMB. Overall, the germination, biochemical, and yield response of French bean in different treatments followed an order of HMB > coal > ALB1 > ALB2 > RHB > control. This study presents a sustainable method of agro-industrial waste management through biochar production and synergistic crop cultivation contributing to the circular economy concept.