Real-time PCR analysis of pyrethroid resistance in Helicoverpa armigera from Turkey

Aim: Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) is a polyphagous pest of a wide range of crops such as cotton, tomato and soybean. Pyrethroid insecticides have commonly used against it in agricultural areas, but excess amount applications of them result in resistance development in the field populations of H. armigera. Resistance development usually occurs with increased metabolism of certain enzymatic systems such as CYP450, GST and esterases. Therefore, expressions of selected CYP450, GST and esterase genes of H. armigera field populations (Adana and Mardin) were compared to those of a susceptible strain by real-time PCR method for analyzing role of these systems in pyrethroid resistance development of H. armigera. Material and Methods: Real-Time PCR Method Results: It was found that H. armigera reacts to pyrethroids mainly by increasing expressions of CYP9A14 gene together with CYP4S1 and CYP9A12 genes. However, analyzed GST and esterase genes expression were not significantly changed in field populations. Conclusion: Consequently, while CYP450 enzyme system is actively involved in pyrethroid resistance, GSTs and esterases enzyme systems don't seem to be actively involved in resistance development against pyrethroid insecticides in H. armigera field populations from Turkey.