UV radiation-induced oxidative stress and DNA damage on Mediterranean flour moth, Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) larvae

Summary Exposure to ultraviolet (UV) radiation is hazardous for all organisms. UV shows numerous effects on insects. In this study, mortality effect of UV on Ephestia kuehniella Zeller, 1879 (Lepidoptera: Pyralidae) larvae was studied. The larvae were exposed to UV radiation (254 and 365 nm) at different time periods (15, 30, 45 and 60 min). After exposure, mortality rate, comet assay studies, antioxidant enzyme activities (SOD, CAT, GST and GPx), and MDA levels were investigated on the larvae. The mortality rate of E. kuehniella larvae increased with increasing exposure times. It was determined that 254 nm was more effective than 365 nm compared to the effects of short (254 nm) and long-wave (365 nm) radiations on mortality rate of E. kuehniella larvae. Likewise mortality rate, 254 nm had more potency than 365 nm on antioxidant enzyme activities and levels of MDA. According to the comet assay results, the tail DNA% and comet tail length significantly increased in all exposure times at 254 nm, but these changes were seen only 45 min and 60 min at 365 nm of UV radiation. Therefore, tail DNA% and tail lenghts of 254 nm radiation could be greater than the tail lenghts of 365 nm UV radiation. As a result, the UV radiation could be effectively as a safe pest control method and as an alternative to environmentally hazardous chemical pesticides.