Journal of Economic Entomology (2002) 95, 143-148

Yong-Biao Liu, Bruce E. Tabashnik, Timothy J. Dennehy, Yves Carrière, Maria A. Sims and Susan K. Meyer (2002)
Oviposition on and mining in bolls of Bt and non-Bt cotton by resistant and susceptible pink bollworm (Lepidoptera: Gelechiidae)
Journal of Economic Entomology 95 (1), 143-148
Abstract: Transgenic cotton that produces insecticidal crystal protein Cry1Ac of Bacillus thuringiensis (Bt) has been effective in controlling pink bollworm, Pectinophora gossypiella (Saunders). We compared responses to bolls of Bt cotton and non-Bt cotton by adult females and neonates from susceptible and Cry1Ac-resistant strains of pink bollworm. In choice tests on caged cotton plants in the greenhouse, neither susceptible nor resistant females laid fewer eggs on Bt cotton bolls than on non-Bt cotton bolls, indicating that the Bt toxin did not deter oviposition. Multiple regression revealed that the number of eggs laid per boll was negatively associated with boll age and positively associated with boll diameter. Females also laid more eggs per boll on plants with more bolls. The distribution of eggs among bolls of Bt cotton and non-Bt cotton was clumped, indicating that boll quality rather than avoidance of previously laid eggs was a primary factor in oviposition preference. Parallel to the results from oviposition experiments, in laboratory no-choice tests with 10 neonates per boll, the number of entrance holes per boll did not differ between Bt cotton and non-Bt cotton for susceptible and resistant neonates. Also, like females, neonates preferred younger bolls and larger bolls. Thus, acceptance of bolls by females for oviposition and by neonates for mining was affected by boll age and diameter, but not by Bt toxin in bolls. The lack of discrimination between Bt and non-Bt cotton bolls by pink bollworm from susceptible and resistant strains indicates that oviposition and mining initiation are independent of susceptibility to Cry1Ac.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Full text of article
Database assignments for author(s): Yong-Biao Liu, Yves Carriere, Bruce E. Tabashnik

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
pesticide resistance of pest
Research topic(s) for beneficials or antagonists:
resistance/tolerance/defence of host

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Pectinophora gossypiella	Cotton (Gossypium)
Bacillus thuringiensis genes in crops (entomopathogen)	Pectinophora gossypiella	Cotton (Gossypium)
Bacillus thuringiensis Cry1A-toxin (entomopathogen)	Pectinophora gossypiella	Cotton (Gossypium)