The present study investigated the biochemical mechanism of abamectin resistance in a Tetranychus urticae Koch population collected from a bean greenhouse (BEYO 2) in Beyobası village in Gazipaşa district, Antalya province and maintained in the laboratory. | Research Article Turk J Agric For 33 (2009) 393-402 © TÜBİTAK doi: Multiple resistance, detoxifying enzyme activity, and inheritance of abamectin resistance in Tetranychus urticae Koch (Acarina: Tetranychidae) Sibel YORULMAZ*, Recep AY** Süleyman Demirel University, Faculty of Agriculture, Plant Protection Department 32260 Çünür, Isparta - TURKEY Received: Abstract: The present study investigated the biochemical mechanism of abamectin resistance in a Tetranychus urticae Koch population collected from a bean greenhouse (BEYO 2) in Beyobası village in Gazipaşa district, Antalya province, and maintained in the laboratory. LC50, 60, 90 levels of BEYO 2 population of T. urticae were determined using a dry film method. The LC50 level of the BEYO 2 strain with abamectin was selected 15 times and was increased from μL 100 mL-1 water to μL 100 mL-1 water. A selected strain showing resistance was named ABA 15 strain. It was investigated whether the resistant strain developed multiple resistance to different pesticide groups. The ABA 15 strain with abamectin resistance developed multiple resistance to chlorpyrifos, propargite, clofentezine, and fenpyroximate. The synergistic activity between abamectin and piperonyl butoxide (PBO), triphenyl phosphate (TPP), and S-benzyl-O,Odiisopropyl phosphorothioate (IBP) was studied in the resistant strain. Application of abamectin with synergists PBO, IBP, and TPP resulted in , , and synergistic ratios, respectively, in the ABA 15 strain. The inheritance of resistance to abamectin of F1 females after reciprocal crosses between resistant and susceptible strains was maternal and paternal incompletely dominant. GSS (susceptible strain), BEYO 2, and ABA 15 strains were investigated in terms of the enzyme activities of esterase, glutathione S-transferase (GST), and monooxygenase (P450). No significant change was determined in esterase enzyme activities of the ABA 15 .
