Q.Highlight any four areas where genetic modification of plants has been useful.

Genetic modification has transformed agriculture by addressing problems that conventional breeding cannot solve quickly or effectively. The NCERT textbook identifies several key areas where this technology has delivered practical benefits.

Tolerance to abiotic stresses like cold, drought, salt, and heat has been engineered into crops, helping them survive harsh environments where they would otherwise fail. This is crucial for expanding cultivation into marginal lands.

Reduced reliance on chemical pesticides comes from inserting genes that make plants resistant to pests. The Bt cotton example—where a bacterial toxin gene protects against bollworms—shows how built-in resistance cuts down repeated insecticide spraying.

Reduced post-harvest losses matter especially in developing countries where storage and transport infrastructure is weak. Genetic modifications that delay ripening or improve shelf life mean less food waste between farm and consumer. …

Genetic engineering has opened remarkable possibilities in agriculture by allowing scientists to introduce specific desirable traits into plants with precision. Unlike traditional breeding, which shuffles entire genomes over many generations, genetic modification targets individual genes, making it possible to address specific agricultural challenges directly. The technology has found practical application in several critical areas where conventional methods struggled to deliver results quickly enough to meet global food security demands.

The four most significant areas where genetic modification has delivered tangible benefits are:

Pest resistance stands as one of the earliest and most successful applications. Scientists have introduced genes from the bacterium Bacillus thuringiensis (Bt) into crops like cotton and corn. These Bt genes produce proteins toxic to specific insect pests but harmless to humans and other animals. Bt cotton, for instance, protects itself against bollworms, dramatically reducing the need for chemical pesticides. Farmers spray less, costs drop, and the environmental burden of insecticide use decreases.

Herbicide tolerance represents another major breakthrough. Crops have been engineered to survive specific herbicides that would normally kill them along with weeds. When farmers plant herbicide-tolerant varieties, they can spray fields to eliminate weeds without harming the crop itself. This simplifies weed management enormously and often allows for reduced tillage practices, which help preserve soil structure and reduce erosion.

Nutritional enhancement addresses hidden hunger—the deficiency of essential vitamins and minerals even when caloric intake is adequate. Golden Rice exemplifies this approach: scientists introduced genes that enable rice grains to produce beta-carotene, a precursor of Vitamin A. In regions where rice is the staple food and Vitamin A deficiency causes blindness and immune problems in children, such biofortified crops offer a sustainable solution. Similar efforts have enriched other crops with iron, zinc, and essential amino acids. …

Method — pick 4 DISTINCT problem areas, one benefit each

Distinctness check — make sure each of the 4 areas solves a DIFFERENT kind of problem, not the same one twice:

1. Pest resistance (biotic stress) → Bt cotton.
2. Abiotic stress tolerance (cold/drought/salt).
3. Reduced post-harvest losses. …