Production of indigenous isolate Bacillus thuringiensis sv2 (Bt sv2) was checked on conventional and nonconventional carbon and nitrogen sources in shake flasks. The effects on the production of biomass, toxin production, and spore formation capability of mosquito toxic strain were determined. Toxicity differs within the same strain depending on the growth medium. Bt sv2 produced with pigeon pe...

Laboratory-selected Bacillus thuringiensis-resistant colonies are important tools for elucidating B. thuringiensis resistance mechanisms. However, cotton bollworm, Helicoverpa zea, a target pest of transgenic corn and cotton expressing B. thuringiensis Cry1Ac (Bt corn and cotton), has proven difficult to select for stable resistance. Two populations of H. zea (AR and MR), resistant to the B. th...

Bt (Bacillus thuringiensis) eggplant may become the first transgenic vegetable crop to be commercialized in the Indian subcontinent. This exploratory study conducted in Maharashtra, India suggests that vegetable farmers are generally receptive to the technology primarily for its pest resistance and cost saving attributes. While economic issues dominate the farmers’ perception of Bt eggplant, et...

Susceptibility to Cry1Ab toxin from Bacillus thuringiensis (Bt) was determined for 12 field populations of neonate corn earworm, Helicoverpa zea (Boddie), from the United States. Earworm larvae were exposed to artificial diet treated with increasing Bt concentrations, and mortality and growth inhibition were evaluated after 7 d. The range of variation in Bt susceptibility indicated by growth in...

Onfarm field trials carried out with Bacillus thuringiensis (Bt) cotton in different states of India show that the technology substantially reduces pest damage and increases yields. The yield gains are much higher than what has been reported for other countries where genetically modified crops were used mostly to replace and enhance chemical pest control. In many developing countries, small-sca...

Transgenic plants producing Bacillus thuringiensis toxins show great promise as insect control agents, provided that effective resistance management strategies are implemented early in their product cycle. To be effective, these strategies require detailed knowledge of the toxins’ mode of action and of the insect’s genetic repertoire of potential resistance genes, knowledge which is still incom...

Genetically engineered maize producing the insecticidal protein Cry3Bb1 from Bacillus thuringiensis (Bt maize) is protected against corn rootworms (Diabrotica spp.), which are serious maize pests in North America and Europe. The aim of the present study was to investigate the interaction of Bt maize (event MON88017) and the entomopathogenic fungus Metarhizium anisopliae for controlling the west...

The gram-positive spore-forming bacteria, Bacillus thuringiensis (Bt) strains produced novel cellulases which could liberate glucose from soluble cellulose, carboxymethyl cellulose (CMC), and insoluble crystalline cellulose. The maximal cellulase activities were obtained after 60 hrs incubation at 28oC in a LB broth medium with 1% CMC. Maximum CMCase activities were got at 40oC and pH 4.0, resp...

The adoption of agricultural technologies, whether developed through biotechnology or other methods, depends on social, political, regulatory and biological parameters. This article first presents an example of a low-input, non-biotechnological method of pest control that, while seemingly reasonable to researchers and extension agents, was not adopted by farmers. It then analyses a method for i...

Bacillus thuringiensis (Bt) Cry toxins have been used widely in pest managements. However, Cry toxins are not effective against sap-sucking insects (Hemiptera), which limits the application of Bt for pest management. In order to extend the insecticidal spectrum of Bt toxins to the rice brown planthopper (BPH), Nilaparvata lugens, we modified Cry1Ab putative receptor binding domains with selecte...