title: Effective dominance of resistance of Spodoptera frugiperda to Bt maize and cotton varieties: implications for resistance management.
abstract: The resistance of fall armyworm (FAW), Spodoptera frugiperda, has been characterized to some Cry and Vip3A proteins of Bacillus thuringiensis (Bt) expressed in transgenic maize in Brazil. Here we evaluated the effective dominance of resistance based on the survival of neonates from selected Bt-resistant, heterozygous, and susceptible (Sus) strains of FAW on different Bt maize and cotton varieties. High survival of strains resistant to the Cry1F (HX-R), Cry1A.105/Cry2Ab (VT-R) and Cry1A.105/Cry2Ab/Cry1F (PW-R) proteins was detected on Herculex, YieldGard VT PRO and PowerCore maize. Our Vip3A-resistant strain (Vip-R) exhibited high survival on Herculex, Agrisure Viptera and Agrisure Viptera 3 maize. However, the heterozygous from HX-R × Sus, VT-R × Sus, PW-R × Sus and Vip-R × Sus had complete mortality on YieldGard VT PRO, PowerCore, Agrisure Viptera, and Agrisure Viptera 3, whereas the HX-R × Sus and Vip-R × Sus strains survived on Herculex maize. On Bt cotton, the HX-R, VT-R and PW-R strains exhibited high survival on Bollgard II. All resistant strains survived on WideStrike, but only PW-R and Vip-R × Sus survived on TwinLink. Our study provides useful data to aid in the understanding of the effectiveness of the refuge strategy for Insect Resistance Management of Bt plants.
authors.affiliation: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture (ESALQ), University of São Paulo (USP), Av. Pádua Dias 11, Piracicaba 13418-900, São Paulo, Brazil.
authors.forename: Renato J
authors.initials: RJ
authors.lastname: Horikoshi
authors.affiliation: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture (ESALQ), University of São Paulo (USP), Av. Pádua Dias 11, Piracicaba 13418-900, São Paulo, Brazil.
authors.forename: Daniel
authors.initials: D
authors.lastname: Bernardi
authors.affiliation: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture (ESALQ), University of São Paulo (USP), Av. Pádua Dias 11, Piracicaba 13418-900, São Paulo, Brazil.
authors.forename: Oderlei
authors.initials: O
authors.lastname: Bernardi
authors.affiliation: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture (ESALQ), University of São Paulo (USP), Av. Pádua Dias 11, Piracicaba 13418-900, São Paulo, Brazil.
authors.forename: José B
authors.initials: JB
authors.lastname: Malaquias
authors.affiliation: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture (ESALQ), University of São Paulo (USP), Av. Pádua Dias 11, Piracicaba 13418-900, São Paulo, Brazil.
authors.forename: Daniela M
authors.initials: DM
authors.lastname: Okuma
authors.affiliation: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture (ESALQ), University of São Paulo (USP), Av. Pádua Dias 11, Piracicaba 13418-900, São Paulo, Brazil.
authors.forename: Leonardo L
authors.initials: LL
authors.lastname: Miraldo
authors.affiliation: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture (ESALQ), University of São Paulo (USP), Av. Pádua Dias 11, Piracicaba 13418-900, São Paulo, Brazil.
authors.forename: Fernando S de A E
authors.initials: FS
authors.lastname: Amaral
authors.affiliation: Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture (ESALQ), University of São Paulo (USP), Av. Pádua Dias 11, Piracicaba 13418-900, São Paulo, Brazil.
authors.forename: Celso
authors.initials: C
authors.lastname: Omoto
mesh_terms: D000818:Animals; D001413:Bacillus thuringiensis / Q000235:genetics; D001938:Brazil; D003368:Gossypium / Q000235:genetics; D006579:Heterozygote; D007300:Insect Control / Q000379:methods; D007305:Insecticide Resistance / Q000502:physiology*; D007814:Larva; D030821:Plants, Genetically Modified; D018411:Spodoptera / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D003313:Zea mays / Q000235:genetics