title: Deltamethrin resistance in the codling moth (Lepidoptera: Tortricidae): inheritance and number of genes involved.
abstract: The inheritance of deltamethrin resistance in Cydia pomonella (L.) has been investigated by crossing a resistant (Rv) and a susceptible (Sv) strain, derived from a population collected in south-eastern France in 1995. Deltamethrin resistance was suspected to be under the control of a kdr-type allele and an enhanced mixed-function oxidase (mfo). F(1) and F(2) progenies were therefore tested through dose-response and enzyme assays. Dose-response relationships indicated that resistance was inherited as an autosomal incompletely recessive (D=-0.199) character, involving at least two genes. Enzyme measures suggested the contribution of 1.2 genes to the expression of mfo, with incomplete dominance (D=0.460). Our results support the hypothesis of a polygenic response to deltamethrin selection in the Rv strain, including a major kdr-type allele with a minor effect of mfos. In the light of these findings, we consider the resistance in codling moth populations in south-eastern France as a product of an adaptive sequential selection process, occurring through the sequential addition of resistance genes.
authors.affiliation: I.N.R.A., U.M.R. Ecologie des Invertébrés, Site Agroparc, 84 914 AVIGNON Cedex 09, France. jbouvier@avignon.inra.fr
authors.forename: J C
authors.initials: JC
authors.lastname: Bouvier
authors.forename: R
authors.initials: R
authors.lastname: Buès
authors.forename: T
authors.initials: T
authors.lastname: Boivin
authors.forename: L
authors.initials: L
authors.lastname: Boudinhon
authors.forename: D
authors.initials: D
authors.lastname: Beslay
authors.forename: B
authors.initials: B
authors.lastname: Sauphanor
mesh_terms: D000818:Animals; D005075:Biological Evolution; D003433:Crosses, Genetic; D007305:Insecticide Resistance / Q000235:genetics*; D020714:Maximum Tolerated Dose; D009036:Moths / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics*; D020412:Multifactorial Inheritance / Q000235:genetics*; D009570:Nitriles; D011722:Pyrethrins / Q000633:toxicity*; D013250:Steroid Hydroxylases / Q000378:metabolism
chemical_list: D009570:Nitriles; D011722:Pyrethrins; C017180:decamethrin; D013250:Steroid Hydroxylases