title: Resistance to lambda-cyhalothrin in Spanish field populations of Ceratitis capitata and metabolic resistance mediated by P450 in a resistant strain.
abstract: BACKGROUND
  The withdrawal of malathion in the European Union in 2009 resulted in a large increase in lambda-cyhalothrin applications for the control of the Mediterranean fruit fly, Ceratitis capitata, in Spanish citrus crops.
  
  
  RESULTS
  Spanish field populations of C. capitata have developed resistance to lambda-cyhalothrin (6-14-fold), achieving LC50 values (129-287 ppm) higher than the recommended concentration for field treatments (125 ppm). These results contrast with the high susceptibility to lambda-cyhalothrin found in three Tunisian field populations. We have studied the mechanism of resistance in the laboratory-selected resistant strain W-1Kλ (205-fold resistance). Bioassays with synergists showed that resistance was almost completely suppressed by the P450 inhibitor PBO. The study of the expression of 53 P450 genes belonging to the CYP4, CYP6, CYP9 and CYP12 families in C. capitata revealed that CYP6A51 was overexpressed (13-18-fold) in the resistant strain. The W-1Kλ strain also showed high levels of cross-resistance to etofenprox (240-fold) and deltamethrin (150-fold).
  
  
  CONCLUSIONS
  Field-evolved resistance to lambda-cyhalothrin has been found in C. capitata. Metabolic resistance mediated by P450 appears to be the main resistance mechanism in the resistant strain W-1Kλ. The levels of cross-resistance found may compromise the effectiveness of other pyrethroids for the control of this species. © 2014 Society of Chemical Industry.
authors.affiliation: Departamento de Biologia Medioambiental, Centro de Investigaciones Biológicas, CSIC, Madrid, Spain.
authors.forename: Rabeh
authors.initials: R
authors.lastname: Arouri
authors.affiliation: INRA, CNRS, Université de Nice Sophia Antipolis, Sophia Antipolis, France.
authors.forename: Gaelle
authors.initials: G
authors.lastname: Le Goff
authors.affiliation: Centre National des Sciences et Technologies Nucléaires (CNSTN), Sidi Thabet, Tunisia.
authors.forename: Hiethem
authors.initials: H
authors.lastname: Hemden
authors.affiliation: Universidad Politécnica de Valencia, CEQA-IAM, Valencia, Spain.
authors.forename: Vicente
authors.initials: V
authors.lastname: Navarro-Llopis
authors.affiliation: Centre National des Sciences et Technologies Nucléaires (CNSTN), Sidi Thabet, Tunisia.
authors.forename: Mariem
authors.initials: M
authors.lastname: M'saad
authors.affiliation: Departamento de Biologia Medioambiental, Centro de Investigaciones Biológicas, CSIC, Madrid, Spain.
authors.forename: Pedro
authors.initials: P
authors.lastname: Castañera
authors.affiliation: INRA, CNRS, Université de Nice Sophia Antipolis, Sophia Antipolis, France.
authors.forename: René
authors.initials: R
authors.lastname: Feyereisen
authors.affiliation: Departamento de Biologia Medioambiental, Centro de Investigaciones Biológicas, CSIC, Madrid, Spain.
authors.forename: Pedro
authors.initials: P
authors.lastname: Hernández-Crespo
authors.affiliation: Departamento de Biologia Medioambiental, Centro de Investigaciones Biológicas, CSIC, Madrid, Spain.
authors.forename: Félix
authors.initials: F
authors.lastname: Ortego
mesh_terms: D000818:Animals; D033622:Ceratitis capitata / Q000235:genetics; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism; D017344:Genes, Insect; D007305:Insecticide Resistance / Q000235:genetics; D007306:Insecticides; D009570:Nitriles; D010882:Piperonyl Butoxide; D011722:Pyrethrins; D013030:Spain; D014416:Tunisia
chemical_list: D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; D003577:Cytochrome P-450 Enzyme System; D010882:Piperonyl Butoxide; C037304:cyhalothrin
keywords: P450 overexpression; fruit fly; insecticide resistance; pyrethroid