title: Detection and geographical distribution of the organophosphate resistance-associated Δ3Q ace mutation in the olive fruit fly, Bactrocera oleae (Rossi).
abstract: BACKGROUND
  The olive fruit fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae), is the most important pest of olives. Its control is based mostly on organophosphate (OP) insecticides, a practice that has led to resistance development. OP resistance in B. oleae has been associated with three mutations in the acetylcholinesterase (AChE), the product of ace gene. The current study presents new diagnostic tests for the detection of the ace mutations and aims at monitoring the frequency of the Δ3Q mutation, which appears associated with resistance at higher OP doses in natural olive fly populations.
  
  
  RESULTS
  An allele-specific polymerase chain reaction (PCR), a PCR-RFLP (restriction fragment length polymorphism) and a Taq-Man test were developed for the Δ3Q mutation detection and a new duplex quantitative PCR assay was designed for the G488S and I214V mutations. Moreover, the frequency of Δ3Q mutation was examined in ten populations of eight countries around the Mediterranean basin. The highest frequencies (10%) were found in Greece and Italy, whereas a gradual decrease of Δ3Q frequency towards the western Mediterranean was noted.
  
  
  CONCLUSIONS
  Robust tests for insecticide resistance mutations at their incipient levels are essential tools to monitor the increase and geographical spread of such mutations. Three different tests were developed for AChE-Δ3Q that indicated its association with OP applications across the Mediterranean.
authors.affiliation: Department of Biochemistry and Biotechnology, University of Thessaly, Greece.
authors.forename: Evdoxia G
authors.initials: EG
authors.lastname: Kakani
authors.forename: Efthymia
authors.initials: E
authors.lastname: Sagri
authors.forename: Michalis
authors.initials: M
authors.lastname: Omirou
authors.forename: Ioannis M
authors.initials: IM
authors.lastname: Ioannides
authors.forename: Kostas D
authors.initials: KD
authors.lastname: Mathiopoulos
mesh_terms: D000110:Acetylcholinesterase / Q000235:genetics* / Q000378:metabolism; D000483:Alleles; D000818:Animals; D007305:Insecticide Resistance / Q000235:genetics*; D007306:Insecticides / Q000494:pharmacology*; D010755:Organophosphates / Q000494:pharmacology*; D012150:Polymorphism, Restriction Fragment Length; D060888:Real-Time Polymerase Chain Reaction; D033621:Tephritidae / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism
chemical_list: D007306:Insecticides; D010755:Organophosphates; D000110:Acetylcholinesterase
keywords: Bactrocera oleae; acetylcholinesterase; diagnostic test; insecticide resistance