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How did Bacillus thuringiensis contribute to pest-resistant cotton, corn, and potato crops?

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A step-by-step diagram shows donor DNA and vector DNA cut with restriction enzymes to create overhangs, mixed and sealed with ligase to form recombinant DNA, which is introduced into bacterial cells. The recombinant DNA replicates as the cells divide, producing clones. — biotechnology Steps involved in the engineering of a recombinant DNA molecule.

Bacillus thuringiensis (Bt) is a soil-dwelling bacterium that naturally produces a protein toxin lethal to specific herbivorous insects. In the context of biotechnology, scientists use genetic engineering to introduce the genes responsible for producing this toxin directly into the genome of crops like cotton, corn, and potatoes.12

By incorporating these genes, the plants are able to produce the Bt protein within their own tissues. When targeted pests ingest the plant material, the protein blocks their digestive system, effectively causing them to stop feeding and die. This technology allows crops to defend themselves against specific pests, such as the Colorado potato beetle or various moth larvae, without the need for broad-spectrum chemical insecticide sprays.1

While this method offers significant agricultural advantages, such as reduced reliance on synthetic pesticides, it also necessitates careful management to prevent insects from developing resistance to the toxin, often through the use of non-Bt crop refuges.1