Cadmium-induced genotoxicity detected by the random amplification of polymorphism DNA in the maize seedling roots

Abstract

In recent years, several plant species have been used as bioindicators, and several tests have been developed to evaluate the toxicity of the environmental contaminants. In this study, the root length and DNA band pattern of root tips in maize (Zea mays L.) seedlings were exposed at different concentration of cadmium pollutant (40 and 80 mg L−1). The results indicated that the root length of maize seedlings reduced with an increasing cadmium concentration. A random amplification of polymorphic DNA (RAPD) analysis from the extracted DNA was carried out using twenty three 10-base pair random primers. Eleven primers produced 72 bands between 221-3044 base pairs in gel electrophoresis. DNA damage became evident as the presence and/or absence of DNA fragments in the treated samples compared to the control groups. The number of disappearing bands in profiles increased from 33 at 40 mgL-1 of cadmium concentration to 45 after exposure to 80 mg L−1 cadmium concentration compared to total bands in control. Three new bands appeared in 40 mgL-1 of cadmium concentration but five in 80 mgL-1 of cadmium concentration. The results showed that RAPD analysis could be a useful tool for detection of genotoxic effects of cadmium toxicity on plants.