title: Dosage consistency is the key factor in avoiding evolution of resistance to phosphine and population increase in stored-grain pests.
abstract: BACKGROUND
  Control of pests in stored grain and the evolution of resistance to pesticides are serious problems worldwide. A stochastic individual-based two-locus model was used to investigate the impact of two important issues, the consistency of pesticide dosage through the storage facility and the immigration rate of the adult pest, on overall population control and avoidance of evolution of resistance to the fumigant phosphine in an important pest of stored grain, the lesser grain borer.
  
  
  RESULTS
  A very consistent dosage maintained good control for all immigration rates, while an inconsistent dosage failed to maintain control in all cases. At intermediate dosage consistency, immigration rate became a critical factor in whether control was maintained or resistance emerged.
  
  
  CONCLUSIONS
  Achieving a consistent fumigant dosage is a key factor in avoiding evolution of resistance to phosphine and maintaining control of populations of stored-grain pests; when the dosage achieved is very inconsistent, there is likely to be a problem regardless of immigration rate.
authors.affiliation: School of Plant Biology, FNAS, The University of Western Australia, Crawley, WA, Australia. shi.mingren@gmail.com
authors.forename: Mingren
authors.initials: M
authors.lastname: Shi
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Collins
authors.forename: T James
authors.initials: TJ
authors.lastname: Ridsdill-Smith
authors.forename: Robert N
authors.initials: RN
authors.lastname: Emery
authors.forename: Michael
authors.initials: M
authors.lastname: Renton
mesh_terms: D000818:Animals; D005075:Biological Evolution; D001517:Coleoptera / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D004305:Dose-Response Relationship, Drug; D002523:Edible Grain / Q000469:parasitology*; D061353:Food Storage; D007305:Insecticide Resistance; D007306:Insecticides / Q000494:pharmacology*; D010720:Phosphines
chemical_list: D007306:Insecticides; D010720:Phosphines; C044646:phosphine
keywords: dosage consistency; immigration rate; individual-based; lesser grain borer; phosphine resistance; two-locus