Effect of Heavy Metals on Growth and Biochemical Components of Plants : With special reference to crop plants grown in vitro

Presence of heavy metals in the soil and water is an inevitable evil in modern day due to industrialization. Heavy metal stress is one of the major abiotic stresses that cause environmental pollution in recent decades. These metals unlike other organic pollutants are not degraded and converted into harmless compounds via biological processes. Hence, they can persist for a long time in the environment and enter into food chain. The effects of aluminium and zinc on growth and Biochemical components were investigated in 20 days old seedlings of Pennisetum americanum (L). Leek and Phaseolus aureus in Hoagland's solution spiked with various concentrations of aluminium and zinc. Total chlorophyll content, glucose and protein declined progressively with increasing the concentration of heavy metals. A significant increase of proline, amino acids and other enzymes were detected in primary leaves after exposure to heavy metals. The strongest effect on these chemicals was found in plants exposed to Aluminium.