"Genetically modified plants can reduce the use of chemical pesticides" . Justify the statement. Write a note each on `B_(t)` toxin and `B_(t)` cotton .

Explanation

* Bacillus thuringiensits produces crystal proteins called Cry proteins which are toxic to larvae of insects like tobacco bud worm.army worm,beetles and mosquitpes. * Cry proteins exists as inactive protoxins and get converted into active toxin binds to the surface of epithelial cells of midgut and creates pores. * This causes swelling and lysis of cells leading to the death of the insect (larva). * The genes ( cry genes) encroding this protein are isolated from the bacterium and incorporated into several crop plants like cotton, tomato, corn, rice, soyabean, etc. * The proteins encoded by the following cry genes control the corresponding pests. *Cry I AC and Cry II Ab control cotton bolIworms. *Cry III Ab controls colarado patato beetle. * Cry III Bb controls corn rootworm.