AP BIOLOGY

Detailed explanation-1: -Most new varieties of grain produce large yields only if they receive large amounts of water, fertilizer, and pesticides. In addition, the machinery, irrigation, and chemicals required by new crop varieties can degrade the soil if they are not used properly.

Detailed explanation-2: -Genetic Engineering. Conventional breeding has been an effective means for developing high-yielding varieties; however, it has its own limitations. The transgenic approach provides a novel way for rice breeders to use genes other than those from rice and its relatives.

Detailed explanation-3: -Higher-yielding seeds (HYV) refer to those that produce large quantities of crops, including rice and wheat. Regular water supply, the highest use of fertilisers, and the application of pesticides with a precise proportion are essential to using these seeds.