Impact of Heavy Metal Toxicity on Germination and Stress Response of Trifolium Repens

Heavy metals are persistent environmental sources affecting soil quality. Therefore, selecting plant species that can germinate and grow under heavy metal stress is critical for phytoremediation. This study examines the effects of varying concentrations of cadmium (Cd²⁺), lead (Pb²⁺), mercury (Hg²⁺), and arsenic (As³⁺) on germination and growth Trifolium repens, with emphasis on its response to heavy metal stress in South African soils. Seeds with uniform size were sampled and placed in plastic dishes with a layer of towel paper on the bottom and were evenly spaced in each dish on the surface of the towel paper with 5 mL of each metal concentrations. The findings revealed that the metal type and concentration significantly impacted almost all the physiological parameters of Trifolium repens at (P 0.05), indicating that the alterations were primarily related to the experimental setup. There was a consistent inverse relationship between metal concentration and plant performance. The best physiological and germination results were achieved at the lowest treatment level (0.5 mM) whereas plants were extremely affected at 10 mM.