Alterations in antioxidant enzyme activities and lipid peroxidation induced by diflubenzuron in the carmine spider mite, Tetranychus cinnabarinus (Boisduval) (Acari: Tetranychidae)

Abstract

ABSTRACTThe eggs, larvae, nymphs and female adults of the carmine spider mite, Tetranychus cinnabarinus (Boisduval) were treated using corresponding sublethal dosages (LC10–LC50) of diflubenzuron. Then we examined the effect on the activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), glutathione-S-transferases (GSTs), the total antioxidant capacity (T-AOC) and malondialdehyde (MDA) content. The results showed that the activities of SOD, CAT and POD at different developmental stages increased with increasing of diflubenzuron concentration, but when diflubenzuron concentration continued to increase, the activities decreased. GSTs activities, T-AOC and MDA content increased with the increasing of diflubenzuron concentration. The change trend of GSTs activities was as follows: eggs < larvae < nymphs < female adults. T-AOC in both nymphs and female mites was higher than that in eggs and larvae, and MDA contents in larvae, nymphs and female adults were always higher than that of eggs. The increasing of MDA concentration indicated that diflubenzuron stress led to lipid peroxidation in organisms. In summary, diflubenzuron stress resulted in oxidative stress and antioxidant enzymes played an important role in reducing oxidative damage in the carmine spider mite.