title: Genetic basis of Spodoptera frugiperda (Lepidoptera: Noctuidae) resistance to the chitin synthesis inhibitor lufenuron.
abstract: BACKGROUND
  An understanding of the genetic basis of insect resistance to insecticides is important for the establishment of insect resistance management (IRM) strategies. In this study we evaluated the inheritance pattern of resistance to the chitin synthesis inhibitor lufenuron in Spodoptera frugiperda.
  
  
  RESULTS
  The LC50 values (95% CI) were 0.23 µg lufenuron mL(-1) water (ppm) (0.18-0.28) for the susceptible strain (SUS) and 210.6 µg mL(-1) (175.90-258.10) for the lufenuron-resistant strain (LUF-R), based on diet-overlay bioassay. The resistance ratio was ≈ 915-fold. The LC50 values for reciprocal crosses were 4.89 µg mL(-1) (3.79-5.97) for female LUF-R and male SUS and 5.74 µg mL(-1) (4.70-6.91) for female SUS and male LUF-R, indicating that the inheritance of S. frugiperda resistance to lufenuron is an autosomal, incompletely recessive trait. Backcrosses of the progeny of reciprocal crosses with the parental LUF-R showed a polygenic effect. The estimated minimum number of independent segregations was in the 11.02 range, indicating that resistance to lufenuron is associated with multiple genes in S. frugiperda.
  
  
  CONCLUSIONS
  Based on genetic crosses, the inheritance pattern of lufenuron resistance in S. frugiperda was autosomal, incompletely recessive and polygenic. Implications of this finding to IRM are discussed in this paper.
authors.affiliation: Department of Entomology and Acarology, University of São Paulo (ESALQ/USP), Piracicaba, São Paulo, Brazil.
authors.forename: Antonio Rogério Bezerra
authors.initials: AR
authors.lastname: do Nascimento
authors.affiliation: Department of Entomology and Acarology, University of São Paulo (ESALQ/USP), Piracicaba, São Paulo, Brazil.
authors.forename: Juliano Ricardo
authors.initials: JR
authors.lastname: Farias
authors.affiliation: Department of Entomology and Acarology, University of São Paulo (ESALQ/USP), Piracicaba, São Paulo, Brazil.
authors.forename: Daniel
authors.initials: D
authors.lastname: Bernardi
authors.affiliation: Department of Entomology and Acarology, University of São Paulo (ESALQ/USP), Piracicaba, São Paulo, Brazil.
authors.forename: Renato Jun
authors.initials: RJ
authors.lastname: Horikoshi
authors.affiliation: Department of Entomology and Acarology, University of São Paulo (ESALQ/USP), Piracicaba, São Paulo, Brazil.
authors.forename: Celso
authors.initials: C
authors.lastname: Omoto
mesh_terms: D000818:Animals; D001549:Benzamides / Q000494:pharmacology*; D002686:Chitin / Q000096:biosynthesis*; D005260:Female; D017344:Genes, Insect / Q000235:genetics; D007305:Insecticide Resistance / Q000235:genetics*; D008297:Male; D018411:Spodoptera / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D005466:Fluorocarbons
chemical_list: D001549:Benzamides; D002686:Chitin; C070364:fluphenacur; D005466:Fluorocarbons
keywords: chitin synthesis inhibitor; fall armyworm; heritability; insect resistance management