Atrazine accumulation and toxic responses in maize Zea mays.

Atrazine accumulation, oxidative stress, and defense response in maize seedlings exposed to extraneous atrazine were studied. Accumulation of atrazine in maize increased with increasing exposure concentration. The abscisic acid (ABA) content was positively correlated with the atrazine concentrations in maize roots and shoots (p < 0.05). Hydroxyl radical (*OH) in maize was determined in vivo with electron paramagnetic resonance spectroscopy. Its intensity was positively correlated with atrazine concentration in roots and shoots (p < 0.05), and higher level of *OH generated in roots than in shoots corresponded to the major accumulation of atrazine in roots. Superoxide dismutase, peroxidase and catalase in roots were up-regulated by atrazine exposure at 1 mg/L compared to the control and malondialdehyde content in roots was enhanced when atrazine exposure concentration reached 10 mg/L. These results suggested the exposure and accumulation of atrazine caused oxidative toxicity and antioxidant response in maize.