Pest Management Science (2016) 72, 289-297
Xun Zhu, Yanjv Yang, Qingjun Wu, Shaoli Wang, Wen Xie, Zhaojiang Guo, Shi Kang, Jixing Xia and Youjun Zhang (2016)
Lack of fitness costs and inheritance of resistance to Bacillus thuringiensis Cry1Ac toxin in a near-isogenic strain of Plutella xylostella (Lepidoptera: Plutellidae)
Pest Management Science 72 (2), 289-297
Resistance to Bacillus thuringiensis (Bt) formulations in insects may be associated with fitness costs. A lack of costs enables resistance alleles to persist, which may contribute to the rapid development and spread of resistance in populations.
To assess the fitness costs associated with Bt Cry1Ac resistance in Plutella xylostella, life tables were constructed for a near-isogenic resistant strain (NIL-R) and a susceptible strain in this study. No fitness costs associated with Cry1Ac resistance in NIL-R were detected, based on the duration of egg and larval stages, the survival of eggs and larvae, adult longevity, fecundity, net reproductive rate, gross reproduction rate, finite rate of increase and mean generation time. Based on log dose–probit lines, resistance in NIL-R is incompletely recessive and results from a single, autosomal, recessive locus; the degree of dominance was estimated to be -0.74 and -0.71 for F1 (resistant female × susceptible male) and F1' (susceptible female × resistant male) progeny respectively.
Assessment of near-isogenic Cry1Ac-resistant and Cry1Ac-susceptible strains of P. xylostella indicated that resistance is not accompanied with fitness costs, and that resistance is incompletely recessive. These findings should be useful in managing the development of Bt Cry1Ac resistance.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Shaoli Wang, Qing Jun Wu
Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
resistance/tolerance/defence of host
Pest and/or beneficial records:
|Bacillus thuringiensis Cry1A-toxin (entomopathogen)||Plutella xylostella|