Unraveling the Growth and Physiological Responses of Spinach to Cadmium Exposure

Vegetables are a crucial part of the food chain. Vegetables are abundant sources of proteins, fats, minerals, carbohydrates, vitamins and antioxidants. The consumption of leafy vegetables is steadily rising in both urban and rural communities. The rising content of cadmium (Cd) in the food chain through the wastewater poses a significant threat to growth of plants and human health. Cadmium interferes with plant processes like transpiration, nitrogen assimilation, photosynthesis, and respiration. Main purpose of this experiment was to investigate the side effects of various exposure durations and various Cd concentrations on the physiology and growth of spinach. This research was conducted using a factorial design with five Cd doses and three exposure durations (25, 50, and 75 days), set up according to CRD and applying three replications. Results indicated that leaf area, root length and plant height were impacted by Cadmium concentrations up to 40 mg kg-1. Additionally, biochemical, and photosynthetic parameters were also affected. Spinach showed tolerance to various levels of cadmium. The highest tolerance index for spinach was observed at 10 mg Cd kg−1 soil after 50 DoE, while the lowest tolerance index was recorded at 40 mg Cd kg−1 soil after 75 DoE. Cd accumulation in the vegetables, daily intake via consumption poses significant health risks. The findings suggest that both the duration of exposure and Cd dosage are critical in determining Cd toxicity, as evidenced by significant reductions in spinach growth and physiological parameters. Consequently, the consumption of such Cd-contaminated vegetables could pose serious health risks to humans.