Monitoring of acaricide resistance and target site mutations inTetranychus urticaeKoch (Acari: Tetranychidae) populations collected from bean fields in Central Anatolia

Tetranychus urticae is an extremely generalist herbivore that can cause serious yield losses in various plants, including beans. Although alternative control options are present to control T. urticae populations in greenhouses, such as biological control, the control of spider mites in open fields has largely relied on chemical pesticides. Determination of resistance status and resistance mechanisms underlying the decreasing susceptibility is of vital importance to design a robust integrated resistance management program. Up to 9- and 15-fold resistance ratios to abamectin and pyridaben, respectively, were determined based on LC50 values. Abamectin showed excellent efficacy, whereas pyridaben application would cause control failure in more than half of the tested populations under suitable spraying conditions. Therefore, the use of pyridaben should be in rotation with other acaricides belonging to different mode of action groups. None of the populations harboured the point mutations at the target sites of abamectin and pyridaben. For the first time, resistance monitoring in T. urticae populations against pyridaben was determined in Turkey, despite its long usage history.