Revision of Helicoverpa armigera insecticide resistance status in Greece

Abstract

The cotton bollworm Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) is a major pest of numerous crops specially cotton and its control is mainly based on the application of insecticides. Studies on the efficacy levels of insecticides are limited in Greece and such information is essential of the implementation of rational IPM schemes. The aim of this study was to investigate the status of resistance against insecticides registered for the control of cotton bollworm, namely spinetoram, emamectin benzoate, lambda-cyhalothrin, cyantraniliprole and chlorantraniliprole on different populations. The insecticide resistance to the tested compounds was evaluated using laboratory dose-response bioassays in three field populations of H. armigera collected from cotton fields located in Larissa, Thessaloniki and Serres/Drama, Greece, during 2020 using artificial diets with chemical overlay. All tested populations of H. armigera remained susceptible to spinetoram (RR = 0.9–1), emamectin benzoate (RR = 1.2–2.4), cyantraniliprole (RR = 2.4–3.1) and chlorantraniliprole (RR = 1–1.9). While, lambda-cyhalothrin exhibited RR values between 4 and 46 folds in the tested populations, suggesting potential cases of resistance development. This study sets the foundation for evidence-based pest management in Greece and facilitates early detection of incipient resistance cases in the future.