2022 journal article
Impact of Caterpillar Increased Feeding Rates on Reduction of Bt Susceptibility
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES, 23(23).
author keywords: tobacco budworm; bollworm; fall armyworm; cotton; Bacillus thuringiensis; MVPII; Cry1Ac; Cry2Ab2; behavioral resistance; increased feeding
MeSH headings : Animals; Hemolysin Proteins / genetics; Hemolysin Proteins / pharmacology; Hemolysin Proteins / metabolism; Endotoxins / genetics; Endotoxins / metabolism; Pest Control, Biological; Plants, Genetically Modified / genetics; Plants, Genetically Modified / metabolism; Bacterial Proteins / genetics; Bacterial Proteins / metabolism; Bacillus thuringiensis Toxins; Moths / genetics; Bacillus thuringiensis / genetics; Bacillus thuringiensis / metabolism; Insecticide Resistance / genetics; Gossypium / metabolism; Larva / metabolism
TL;DR:
The hypothesis that increased feeding rate is a behavioral mechanism for reducing caterpillar susceptibility to Bt is supported and the literature reviewed support the hypothesis.
(via Semantic Scholar)
open access via www.mdpi.com (publisher PDF)
UN Sustainable Development Goal Categories
2. Zero Hunger
(Web of Science)
3. Good Health and Well-being
(OpenAlex)
Source: Web Of Science
Added: January 3, 2023
The use of insect-resistant transgenic crops producing Bacillus thuringiensis protein Cry toxins (Bt) to control caterpillars is wide-spread. Development of a mechanism to prevent Bt from reaching its target site in the digestive system could result in Bt resistance and resistance to other insecticides active per os. Increased feeding rates by increasing temperature in tobacco budworms, Chloridea virescens, and bollworms, Helicoverpa zea, decreased Bt Cry1Ac susceptibility and mortality. The same was found in C. virescens for Bollgard II plant extract containing Bt Cry1Ac and Cry2Ab2 toxins. Furthermore, H. zea from the same inbred laboratory colony that fed faster independent of temperature manipulation were less susceptible to Bt intoxication. A laboratory derived C. virescens Bt resistant strain demonstrated a higher feeding rate on non-Bt artificial diet than the parental, Bt susceptible strain. A laboratory-reared Bt resistant fall armyworm, Spodoptera frugiperda, strain also fed faster on non-Bt diet compared to Bt susceptible caterpillars of the same species, both originally collected from corn. The studies in toto and the literature reviewed support the hypothesis that increased feeding rate is a behavioral mechanism for reducing caterpillar susceptibility to Bt. Its possible role in resistance needs further study.