Impact of Kolanut Biochar on Corchorus olitorius Growth and Nutritional Value in Cadmium-Polluted Soil

Abstract

ABSTRACT Jute (Corchorus olitorius), a nutritionally significant crop, faces severe threats from cadmium (Cd) contamination, primarily originating from industrial waste, which poses substantial health risks to consumers. This study investigated the effectiveness of kolanut-derived biochar, produced via pyrolysis at 400 °C, in mitigating Cd toxicity and enhancing the growth and nutritional quality of jute cultivated in Cd-contaminated loamy soil. The experimental setup involved twelve pots subjected to various treatments: a control, Cd-only (27mg CdCl₂), and Cd combined with either 1% or 3% biochar. Over four weeks, physiological parameters, chlorophyll content, and nutrient uptake were meticulously monitored. The findings revealed a significant reduction in chlorophyll content across all biochar treatments, with the 3% biochar application exhibiting the lowest values. While 1% biochar showed a marginal improvement in plant height, the higher concentration (3%) led to a notable decrease in essential mineral elements such as magnesium (Mg) and calcium (Ca) in both leaves and shoots. This suggests that the induction of nutrient imbalance and potential competitive interactions with metals. Although kolanut pod biochar demonstrated some partial ameliorative effects against Cd stress, its overall efficacy was limited, and in certain instances, it increased the negative impacts on nutrient uptake. These results stress the importance of site-specific considerations for biochar application, underlining the necessity for optimized concentrations, extended study durations, and the exploration of diverse biochar types to achieve effective phytoremediation in soils contaminated with cadmium.