Genotoxic effects of heavy metals in Trachyspermum ammi (L.) Sprague

Heavy metals are ubiquitous in nature. Toxicity of metals depends upon their optimum level in environment. Chromosomal plant assay is an important tool for the estimation of genome damaging property of the pollutants above the optimum level. In the present investigation on ajwain (Trachyspermum ammi (L.) Sprague), cyto-chromotoxicty was evaluated in terms of reduced mitotic activity and various mitotic irregularities comprising scattering, stickiness, precocious movement, laggards, bridges, c-mitosis, etc. Five concentrations (50, 75,100,150 and 200 ppm) of both the metal salts (Pb(NO3)2 and Cr2O3) were used. Dose dependent increase in the chromosomal aberrations and decrease in mitotic indieces were observed. On comparing mitotoxicity of both the metals, Pb was more growth inhibitory and mitotoxic than Cr.