Class 12 Biology - Chapter Biotechnology and its Application NCERT Solutions | What is meant by the term bio-pesticide?

Bio- pesticides are the substances which are used to control the pest and are non- chemical in nature, safer for the environment than the chemical pesticides and fertilizers. A popularly known example is, Bacillus thuringiensis which is a bacterium that is pathogenic for the number of insect pests and Bt toxin is obtained from this. Its lethal effect is mediated by toxin that it produces. Through the recombinant DNA proteins methods, the toxin gene can be introduced directly into the genome of the plant where it is expressed and provide protection against the insect pest of the plant. In this, after ingestion of the proteins (inactivate proteins) by the insect, this protoxin cleaved by protease, results in the shorter version of proteins and shows toxicity/ acidity and due to presence of alkaline nature Bt toxin get activated by binding inside of the insect’s gut and damages the surface epithelium by creating pores which causes cells swelling and lysis; and hence the insect dies.