Read the passage and answer the following questions:
Genetic modification (GM) has been utilised to create custom-designed plants that serve as alternative resources for industries, producing starches, fuels, and pharmaceuticals. Biotechnology in agriculture has numerous applications, one of which involves developing pest-resistant plants to reduce the reliance on chemical pesticides. This is achieved by introducing the Bt toxin gene from the bacterium Bacillus thuringiensis (Bt) into plants, creating what is known as a bio-pesticide. Notable examples include Bt cotton, Bt corn, rice, tomato, potato, and soybean. Bt toxin is a naturally occurring insecticidal protein produced by certain strains of Bacillus thuringiensis. During a specific phase of their growth, these bacteria form protein crystals containing toxic substances. These crystals harbour inactive protoxins, which, when activated, become lethal to targeted insects. Different Bt toxin genes, such as cryIAc and cryIIAb, have been isolated and introduced into various crop plants, depending on the crop and the specific pests targeted, as Bt toxins are often insect-group specific. By incorporating these genes, plants gain inherent resistance to insects without the need for synthetic insecticides. This advancement in biotechnology has significant implications for sustainable and eco-friendly agricultural practices.
Which of the following is not an advantage of GM crops?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Increased reliance on chemical pesticides (pest-resistant crops).
The passage states that pest-resistant plants are developed “to reduce the reliance on chemical pesticides”. So increased reliance on chemical pesticides is the opposite of what GM crops do.
GM crops carry genes that give them useful traits. The book lists these gains: more tolerance to abiotic stresses, less reliance on chemical pesticides, fewer post-harvest losses, better use of minerals and higher nutritional value of food.
Option (1) Increased reliance on chemical pesticides (pest-resistant crops). — Not an advantage of GM crops. Pest-resistant GM crops such as Bt cotton make their own insecticidal protein, so farmers need to spray less pesticide, not more.
Option (2) Enhanced nutritional value of food. — An advantage of GM crops. Golden rice is an example: it is Vitamin ‘A’ enriched rice.
Option (3) Helped to reduce post-harvest losses. — An advantage of GM crops. Genetic modification has helped to reduce the losses of produce after harvest.
Option (4) Made crops more tolerant to abiotic stresses (cold, drought, salt, heat). — An advantage of GM crops. GM has made crops more tolerant to cold, drought, salt and heat.