Susceptibility of a field-derived, Bacillus thuringiensis-resistant strain of diamondback moth to in vitro-activated Cry1Ac toxin.
Resistant and susceptible populations of the diamondback moth (Plutella xylostella) were tested with crystalline, solubilized, and partially and fully activated forms of the Bacillus thuringiensis Cry1Ac delta-endotoxin. Fully activated toxin greatly reduced the resistance ratio (ratio of the 50% lethal concentration for the resistant population to that for the susceptible population) of the resistant population, suggesting that a defect in toxin activation is a major resistance mechanism.
Sayyed
A H
AH
Department of Biological Sciences, Imperial College of Science, Technology, and Medicine, Silwood Park, Ascot, Berkshire SL5 7PY, United Kingdom.
Gatsi
R
R
Kouskoura
T
T
Wright
D J
DJ
Crickmore
N
N
D000818:Animals; D001413:Bacillus thuringiensis / Q000378:metabolism*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000633:toxicity*; D001427:Bacterial Toxins; D004731:Endotoxins / Q000633:toxicity*; D006460:Hemolysin Proteins; D007305:Insecticide Resistance; D009036:Moths / Q000187:drug effects*
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis