Improving beetroot growth and heavy metal tolerance with biochar under wastewater irrigation across multiple sites

Abstract

Wastewater containing heavy metals can lead to soil and crop accumulation, thus posing a risk to the environment. Biochar, being a rich carbon-containing organic fertilizer, can reduce these adverse impacts by increasing soil fertility. This study was conducted to assess the biochar-treated wastewater for beetroot cultivation using Beta vulgaris L. at three locations in Faisalabad, namely, Directorate of Farms UAF, Uchkera Farm, and Satyana Farm, Faisalabad, using an RCBD factorial design with three wastewater treatments, namely, UAF sewage, Madhuana, and Paharang drains. As a result, pigments increased (Chl a/b 25%, carotenoids 25%), and physiological charac - teristics improved (RWC 25%, electrolyte leakage -20%). The elevated levels of heavy metals were lowered by biochar. Heavy metal buildup in beets was significantly enhanced by wastewater irrigation, but most metals were successfully reduced by applying biochar, improving crop safety and lowering environmental risk. In general, 2024 performed better than 2023. While biochar further improves performance and reduces the dangers of heavy metals, wastewater irrigation increases beetroot growth, yield, and stress tolerance, encouraging safer and more sustainable crop production.