Genetic mapping of resistance to Bacillus thuringiensis toxins in diamondback moth using biphasic linkage analysis

Abstract

Transgenic plants producing environmentally benign Bacillus thuringiensis (Bt) toxins are deployed increasingly for insect control, but their efficacy will be short-lived if pests adapt quickly

Sequence variation in the cadherin gene of Ostrinia nubilalis: a tool for field monitoring

“…Screening P. xylostella for survival on Cry1A and Cry1F toxins suggested cross resistance was imparted by a single gene (Tabashnik et al, 1997). This was corroborated when a major autosomal locus inherited as a recessive trait was identified (Heckel et al, 1999). Cadherin was implicated as a resistance factor by phenotypic association in P. gossypiella (Morin et al, 2003) and transposon knockout in H. virescens (Gahan et al, 2001).…”

A heterozygous moth genome provides insights into herbivory and detoxification

“…Recently, the total cost of damage and management worldwide was estimated at $4-5 billion per annum 5,6 . This insect is the first species to have evolved resistance to dichlorodiphenyltrichloroethane (DDT) in the 1950s 7 and to Bacillus thuringiensis (Bt) toxins in the 1990s 8 and has developed resistance to all classes of insecticide, making it increasingly difficult to control 9,10 . P. xylostella provides an exceptional system for understanding the genetic and molecular bases of how insect herbivores cope with the broad range of plant defenses and chemicals encountered in the environment (Supplementary Fig.…”

RecombinantBacillus thuringiensisstrain shows high insecticidal activity againstPlutella xylostellaandLeptinotarsa decemlineatawithout affecting nontarget species in the field

“…One strategy to delay resistance is to use alternative insecticidal proteins with different modes of action (Bosch et al 1994;Saraswathy and Kumar 2004). Researchers found that the resistance allele of P. xylostella confers cross-resistance to Cry1Aa, Cry1Ab, Cry1Ac, Cry1Fa and Cry1Ja, but not to Cry1Ba, Cry1Bb, Cry1Ca, Cry1Da, Cry1Ia or Cry2Aa (Tabashnik et al 1997(Tabashnik et al , 2000Heckel et al 1999). Ferré and van Rie (2002) asserted that the binding site of latter toxins in P. xylostella was different from those toxins to which P. xylostella have evolved resistance.…”