Induction of oxidative stress and dna damage to root cells of allium cepa l. by copper and lead

The toxicity of copper (Cu) and lead (Pb) was evaluated using Allium cepa L. Healthy onion bulbs of relatively equal size were grown for 3 weeks in half-strength Hoagland’s solution spiked with copper and lead individually to achieve 0.1, 0.3, and 0.5 mM of the metals. Nutrient solution devoid of these metals served as control. Parameters investigated include root length, number of roots, lipid peroxidation, and cytogenetics. The results of this study indicate that these metals consistently inhibited root growth, induced chromosomal aberration, and increased lipid peroxidation. The study also revealed that the effects were concentration dependent. It was found that A. cepa was very sensitive to copper and lead treatments, suggesting that it is one of the ideal plants that could be used as indicators to monitor pollution of the environment by these metals