Explain: plant breeding.

(N/A) Traditional farming can only yield a limited biomass as food for humans and animals.
- Better management practices and increases in acreage can increase yield,but only to a limited extent.
- Plant breeding as a technology has helped increase yields to a very large extent.
- The Green Revolution was dependent to a large extent on plant breeding techniques for the development of high-yielding and disease-resistant varieties in wheat,rice,maize,etc.
Plant breeding is the purposeful manipulation of plant species in order to create desired plant types that are better suited for cultivation,provide better yields,and are disease-resistant.
Conventional plant breeding has been practiced for thousands of years; since the beginning of human civilization,recorded evidence of plant breeding dates back to $9,000-11,000$ years ago.
Many present-day crops are the result of domestication in ancient times.
Today,all our major food crops are derived from domesticated varieties.
- Classical plant breeding involves crossing or hybridization of pure lines,followed by artificial selection to produce plants with desirable traits of higher yield,nutrition,and resistance to diseases.
Through plant breeding,increased crop yield and improved quality can be obtained. Increased tolerance to environmental stresses (salinity,extreme temperatures,drought),resistance to pathogens (viruses,fungi,and bacteria),and increased tolerance to insect pests are also key objectives.