Micronucleus frequency and lipid peroxidation in Allium sativum root tip cells treated with gibberellic acid and cadmium.

Gibberellic acid (GA(3)) is a very potent hormone whose natural occurrence in plants controls their development. Cadmium is a particularly dangerous pollutant due to its high toxicity and great solubility in water. In this study, the effect of GA(3) on Allium sativum root tip cells was investigated in the presence of cadmium. A. sativum root tip cells were exposed to CdNO(3) (50, 100, 200 microM), GA(3) (10-3 M), both CdNO(3) and GA(3). Cytogenetic analyses were performed as micronucleus (MN) assay and mitotic index (MI). Lipid peroxidation analysis was also performed in A. sativum root tip cells for determination of membrane damage. MN exhibited a dose-dependent increase in Cd treatments in A. sativum. GA(3) significantly reduced the effect of Cd on the MN frequency. MN was observed in GA(3) and GA(3) + 50 mum Cd treatments at very low frequency. MI slightly decreased in GA(3) and GA(3) + Cd treatments. MI decreased more in high concentrations of Cd than combined GA(3) + Cd treatments. The high concentrations of cadmium induce MN, lipid peroxidation and lead to genotoxicity in A. sativum. Current work reveals that the effect of Cd on genotoxicity can be partially restored with GA(3) application.