title: Cross-resistance to insecticides in a malathion-resistant strain of Ceratitis capitata (Diptera: Tephritidae).
abstract: Resistance to malathion has been reported in field populations of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), in areas of Spain where an intensive use of this insecticide was maintained for several years. The main goal of this study was to determine whether resistance to malathion confers cross-resistance to different types of insecticides. Susceptibility bioassays showed that the malathion-resistant W-4Km strain (176-fold more resistant to malathion than the susceptible C strain) has moderate levels of cross-resistance (three- to 16-fold) to other organophosphates (trichlorphon, diazinon, phosmet and methyl-chlorpyrifos), the carbamate carbaryl, the pyrethroid lambda-cyhalothrin, and the benzoylphenylurea derivative lufenuron, whereas cross-resistance to spinosad was below two-fold. The W-4Km strain was selected with lambda-cyhalothrin to establish the lambda-cyhalothrin-resistant W-1Klamda strain (35-fold resistant to lambda-cyhalothrin). The synergistic activity of the esterase inhibitor DEF with lambda-cyhalothrin and the increase in esterase activity in the W-1Klamda strain suggests that esterases may be involved in the development of resistance to this insecticide. Our results showed that resistance to malathion may confer some degree of cross-resistance to insecticides currently approved for the control of Mediterranean fruit fly in citrus crops (lambda-cyhalothrin, lufenuron, and methyl-chlorpyrifos). Especially relevant is the case of lambda-cyhalothrin, because we have shown that resistance to this insecticide can rapidly evolve to levels that may compromise its effectiveness in the field.
authors: Departamento de Biología Medioambiental, Centro de Investiga-clones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain.
authors: Francisco
authors: F
authors: Couso-Ferrer
authors: Rabeh
authors: R
authors: Arouri
authors: Beatriz
authors: B
authors: Beroiz
authors: Nathalia
authors: N
authors: Perera
authors: Amelia
authors: A
authors: Cervera
authors: Vicente
authors: V
authors: Navarro-Llopis
authors: Pedro
authors: P
authors: Castañera
authors: Pedro
authors: P
authors: Hernández-Crespo
authors: Félix
authors: F
authors: Ortegoa
mesh_terms: D000818:Animals; D033622:Ceratitis capitata / Q000235:genetics; D018432:Drug Resistance, Multiple; D007305:Insecticide Resistance / Q000235:genetics; D007306:Insecticides; D008294:Malathion; D009570:Nitriles; D063086:Organothiophosphates; D010574:Pesticide Synergists; D011722:Pyrethrins; D012641:Selection, Genetic
chemical_list: D007306:Insecticides; D009570:Nitriles; D063086:Organothiophosphates; D010574:Pesticide Synergists; D011722:Pyrethrins; C006863:butyl phosphorotrithioate; D008294:Malathion; C037304:cyhalothrin