Question

What is a bagging technique? How is it useful in a plant breeding programme?

Answer 1

Hint: Plant breeding is a technique that helps in the production of the desired quality of the plant. The plants formed by this technique are generally resistant to pathogens, increased tolerance to environmental stresses and are more tolerant to insect pests.

Complete answer:
Traditional farming can only yield limited biomass, as food for humans and animals. Better management practices and an increase in acreage can increase yield, but only to a limited extent. Plant breeding as a technique has helped increase yields to a very large extent. When we talk about plant breeding, it is generally referred to as a purposeful manipulation of plant species which is done so as to create desired plant types that are better suited for cultivation, give better yields and are resistant to many contagious diseases related to plants.

Conventional plant breeding techniques came into existence long ago. They have been taken into practice for thousands of years since the beginning of human civilization and their recorded evidence of plant breeding dates back to 9,000 - 11,000 years ago. Many present-day crops are derived from domestication in ancient times. All the varieties of the major crops that we consume are generally derived from domesticated crops. Mainly the breeding of the plants involves crossing or hybridisation of pure lines which is then followed by artificial selection for the production of plants with desired traits of higher yield, nutrition and resistance to diseases. With advancements in genetics, molecular biology and tissue culture, plant breeding is now increasingly being carried out by using molecular genetics tools.

We all know that if a female parent bears bisexual flowers for such plants the removal of anthers from the flower bud is necessary before the anther dehisces by using a pair of forceps is. This step is referred to as emasculation. The flowers that have been emasculated need to be covered with a bag of suitable size, generally made up of butter paper so as to prevent contamination of its stigma with unwanted pollen. This process is called bagging. It is useful in a plant breeding programme because it ensures that pollen grains of desired quality will fertilize the stigma for the development of desired plant variety.

Note: Green revolution was one of the biggest revolutions that are dependent to a large extent on plant breeding techniques that have played an important role in the development of high-yielding and disease-resistant varieties in plants of wheat, rice, maize, etc. This revolution took place not only to meet the national requirements in food production but also helped us even to export it.