GROWTH PARAMETERS AND BIOACCUMULATION POTENTIALS OF LEAFY VEGETABLES GROWN ON AUTOMOBILES WORKSHOP SOIL

ABSTRACT This study evaluated the growth parameters and bioaccumulation potentials of two leafy vegetables, Amaranthushybridus and Ocimumgratissimum, grown on soil collected from an automobile workshop environment. Soil samples were obtained from multiple points around the workshop and compared with uncontaminated control soil. The experiment was conducted under controlled screen house conditions using a completely randomized design. Growth parameters such as plant height, number of leaves, leaf area, fresh weight, dry weight, and chlorophyll content were monitored, while concentrations of heavy metals (Cr, Ni, Cd, Cu, Mn, and Pb) in soil and plant tissues were determined using atomic absorption spectrophotometry. Results revealed elevated levels of heavy metals in the contaminated soil compared to the control. Correspondingly, both plant species grown on the polluted soil exhibited reduced growth performance, including lower plant height, leaf number, leaf area, and biomass. Bioaccumulation analysis showed that both Amaranthushybridus and Ocimumgratissimum absorbed and accumulated heavy metals in their tissues, with varying bio-concentration factors across metals and plant parts. Chlorophyll content also showed slight variations, indicating possible physiological stress. The findings demonstrate that soils from automobile workshop environments can significantly impair plant growth and promote the accumulation of potentially toxic heavy metals in edible plant tissues. This poses a serious risk to human health through the food chain. The study highlights the need for proper management of automobile wastes and caution in cultivating edible crops on contaminated soils.