Reversal of resistance to Bacillus thuringiensis in Plutella xylostella

• Published in: Proceedings of the National Academy of Sciences - PNAS 1994-05, Vol.91 (10), p.4120-4124
• Main Authors: Tabashnik, Bruce E., Finson, Naomi, Groeters, Francis R., Moar, William J., Johnson, Marshall W., Luo, Ke, Adang, Michael J.
• Format: Article
• Language: English
• Subjects: Animals; appareil digestif; Bacillus thuringiensis; Bacillus thuringiensis - pathogenicity; Bacterial Proteins - metabolism; Bacterial Proteins - toxicity; Bacterial Toxins - metabolism; Bacteriology; Bioassay; Biological Assay; biological differences; Butterflies & moths; cell membranes; chemical resistance; diferencias biologicas; difference biologique; digestive system; Drug Resistance; Endotoxins - metabolism; Endotoxins - toxicity; Hemolysin Proteins; Insect colonies; Insect larvae; Insect pests; insecticidas; insecticide; insecticides; Larva; Larvae; Lepidoptera; membrana mucosa; membranas celulares; membrane cellulaire; Microvilli - metabolism; Mortality; Moths - metabolism; Moths - microbiology; mucous membrane; muqueuse; Pest Control, Biological; Pesticides; Pests; Plutella xylostella; Plutellidae; resistance aux produits chimiques; resistencia quimica; sistema digestivo; Toxicity; toxinas; toxine; Toxins
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.91.10.4120

Continued success of the most widely used biopesticide, Bacillus thuringiensis, is threatened by development of resistance in pests. Experiments with Plutella xylostella (diamondback moth), the first insect with field populations resistant to B. thuringiensis, revealed factors that promote reversal of resistance. In strains of P. xylostella with 25- to 2800-fold resistance to B. thuringiensis compared with unselected strains, reversal of resistance occurred when exposure to B. thuringiensis was stopped for many generations. Reversal of resistance was associated with restoration of binding of B. thuringiensis toxin CryIA(c) to brush-border membrane vesicles and with increased biotic fitness. Compared with susceptible colonies, revertant colonies had a higher proportion of extremely resistant individuals. Revertant colonies responded rapidly to reselection for resistance. Understanding reversal of resistance will help to design strategies for extending the usefulness of this environmentally benign insecticide.