Page 71 - Biology - XII

EXPERIMENT - 12

Objective
To study controlled pollination—emasculation, bagging, and tagging.

Principle/Theory
Pollination is the process of transfer of pollens from the (mature) anther to (mature) stigma by various
agencies. Controlled pollination is done by human intervention using desirable male and female parents
with desired traits. The process that can be brought under human control is emasculation. The whole
process of controlled pollination till the end result involves

• Emasculation. Removal of anthers from the female fl ower,
• Bagging. Isolation of the emasculated fl ower by enclosing it in a plastic bag/the whole plant in a mus-
lin cage, and
• Tagging. Naming the plant with necessary information.

Materials Required
Specimen, bag, forceps, etc.

Procedure
1. Observe the specimens.
2. Compare the comments mentioned.

3. Draw the diagram in your record fi le and write comments.

Bag

Forceps
Tag

Rice plant

Spikelet of paddy (rice) A single fl ower Emasculation in rice fl ower Bagging and tagging
of rice plant

Fig. 12.1: Emasculation in rice fl ower; bagging and tagging of rice plant

Comments
1. It is the technique and diff erent processes used for hybridisation in plant breeding.
2. Emasculation is removal of anthers from the fl ower before they ripe so as to check self-pollination.

3. Bagging or caging is done after the process of emasculation. It is done to isolate the fl ower/plant so
that foreign pollens may not come in contact with the stigma. The bags are kept till seed setting is
completed in the plant.

4. Tagging is done for proper labelling of fl owers/plants. It is named female parent (1st) and then male
parent and a record number and also date.

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