GM crops are designed to develop natural resistance against insects and pests. Which of the following crops are modified using Bacillus thuringiensis?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → All of the above
Bt toxin is made by the bacterium Bacillus thuringiensis (Bt). Its gene has been cloned and expressed in crop plants, so the plants make their own insecticide and resist insect pests without chemical sprays. The book lists Bt cotton, Bt corn, rice, tomato, potato and soyabean as examples. Every pair in options (1), (2) and (3) comes from this list.
Option (1) Corn and cotton — Correct statement, but it is only one of the correct points, so on its own it is not the answer. Bt cotton and Bt corn are the best-known Bt crops.
Option (2) Tomato and rice — Correct statement, but it is only one of the correct points, so on its own it is not the answer. Tomato and rice are also in the book’s list of crops given the Bt toxin gene.
Option (3) Potato and soyabean — Correct statement, but it is only one of the correct points, so on its own it is not the answer. Potato and soyabean complete the book’s list of Bt crops.
NCERT Extract:
Biotechnological Applications in Agriculture – “… Bt toxin is produced by a bacterium called Bacillus thuringiensis (Bt for short). Bt toxin gene has been cloned from the bacteria and been expressed in plants to provide resistance to insects without the need for insecticides; in effect created a bio-pesticide. Examples are Bt cotton, Bt corn, rice, tomato, potato and soyabean etc.”