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

(N/A) Various artificial hybridization techniques,used in crop improvement programmes,involve the removal of anthers from bisexual flowers without affecting the female reproductive part (pistil) through a process called emasculation.
After emasculation,these flowers are covered with suitable bags,generally made of butter paper,to prevent contamination of the stigma by unwanted pollen grains.
This process is known as bagging.
This technique is crucial in plant breeding programmes because it ensures that only pollen grains from desirable plants are used for the fertilization of the stigma,thereby allowing the development of a plant variety with desired traits.