title: Possibly similar genetic basis of resistance to Bacillus thuringiensis Cry1Ab protein in 3 resistant colonies of the sugarcane borer collected from Louisiana, USA.
abstract: The sugarcane borer, Diatraea saccharalis (F.), is a major maize borer pest and a target of transgenic maize expressing Bacillus thuringiensis (Bt) proteins in South America and the mid-southern region of the United States. Evolution of resistance in target pest populations is a great threat to the long-term efficacy of Bt crops. In this study, we compared the genetic basis of resistance to Cry1Ab protein in 3 resistant colonies of sugarcane borer established from field populations in Louisiana, USA. Responses of larvae to the Cry1Ab protein for the parental and 10 other cross colonies were assayed in a diet-incorporated bioassay. All 3 resistant colonies were highly resistant to the Cry1Ab protein with a resistance ratio of >555.6 fold. No maternal effect or sex linkage was evident for the resistance in the 3 colonies; and the resistance was functionally nonrecessive at the Cry1Ab concentrations of ≤ 3.16 μg/g, but it became recessive at ≥10 μg/g. In an interstrain complementation test for allelism, the F1progeny from crosses between any 2 of the 3 resistant colonies exhibited the similar resistance levels as their parental colonies, indicating that the 3 colonies most likely shared a locus of Cry1Ab resistance. Results generated from this study should provide useful information in developing effective strategies for managing Bt resistance in the insect.
authors.affiliation: Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA.
authors.forename: Fei
authors.initials: F
authors.lastname: Yang
authors.affiliation: Monsanto Company, Chesterfield, Monsanto, USA.
authors.forename: Mao
authors.initials: M
authors.lastname: Chen
authors.affiliation: Monsanto Company, Chesterfield, Monsanto, USA.
authors.forename: Anilkumar
authors.initials: A
authors.lastname: Gowda
authors.affiliation: Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA.
authors.forename: David L
authors.initials: DL
authors.lastname: Kerns
authors.affiliation: Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA.
authors.forename: Fangneng
authors.initials: F
authors.lastname: Huang
mesh_terms: D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D005260:Female; D005816:Genetic Complementation Test; D006460:Hemolysin Proteins; D040582:Inheritance Patterns; D007305:Insecticide Resistance / Q000235:genetics; D008297:Male; D009036:Moths / Q000235:genetics*
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis
keywords: Bacillus thuringiensis; Diatraea saccharalis; genetics; interstrain complementation test; resistance