Toxicological Evaluation of Certain Pesticides on the two-Spotted Spider Mite, Tetranychus urticae Koch (Acari: Tetranychidae) on Cucumber Plants Under Field Conditions

Abstract

The two-spotted spider mite, T. urticae, is a significant global agricultural pest. It has become highly resistant to numerous pesticides and is incredibly polyphagous. Herein, five pesticides were tested for their ability to control T. urticae: sulfoxaflor + spinetoram, emamectin benzoate, thiamethoxam, spirodiclofen, and etoxazole in the Manfalout and Qusia districts in Assiut Governorate, Egypt during the 2021 and 2022 seasons. The results revealed that all pesticides were effective on T. urticae based on the mean reduction percentage (the ranges were 62.75%-68.00%) during the 2021 season on cucumber plants in Manflout district. Further, the most potent pesticides in Qusia district were thiamethoxam, spirodiclofen, and emamectin benzoate and the mean reduction percentage were 63.39%, 58.31%, and 56.75%, respectively during the 2021 season. In 2022 season, the most toxic pesticides were thiamethoxam, etoxazole, and emamectin benzoate in Manflout district whereas, in Qusia district, the most powerful pesticides were spirodiclofen, etoxazole, and emamectin benzoate and the mean reduction percentage were 60.00%, 57.67%, and 56.75%, respectively. The tested pesticides are an effective tool that can be used in integrated pest management (IPM) programs against T. urticae on cucumber.