What is bagging technique? How is it useful in a plant breeding programme?
Bagging technique is the process of covering emasculated flowers with a bag of suitable size, generally made up of butter paper. In bisexual flowers, after removal of anthers (emasculation) before anther dehiscence, the flowers are covered with bags to prevent contamination of the stigma with unwanted pollen. In unisexual flowers, female flower buds are bagged before the flowers open.
Bagging is useful in plant breeding programmes as it is an essential part of artificial hybridisation, which is one of the major approaches of crop improvement. It ensures that only the desired pollen grains are used for pollination by protecting the stigma from contamination with unwanted pollen. When the stigma attains receptivity, mature pollen grains from the male parent are dusted on the stigma, and the flower is rebagged. This allows breeders to combine desirable characters to produce commercially 'superior' varieties.
Explanation
The context explains bagging as a technique where emasculated flowers are covered with butter paper bags to prevent unwanted pollen from contaminating the stigma. This is crucial in artificial hybridisation for crop improvement, as it ensures controlled pollination with only desired pollen grains. The technique helps breeders produce superior varieties by combining desirable characters from different plants.