Demonstration of hybridization technique Biology Standard XII

 Practical Notebook Biology Standard XII

Biology 

Answeres

Practical Notebook
Standard XII

Class-12th

science

Click here download in PDF

9. Demonstration of hybridization technique 

Introduction Hybridization is one of the methods of crop improvement undertaken to combine the and female parents.  

The technique involves the following steps: 

desired, useful characteristics from two different pure varieties of plant species, selected as male & Collection of pollen grains 

(Anthesis): Pollen grains from the flower of the selected male parent are collected in sterile paper bags and are stored in clean and dry vials at a cool place.  The collection is done in the early hours of the morning.  Day, date, and time of Anthesis are recorded.  b. 

 Emasculation: 

It is the removal of young anthers of the stamens in the plant selected as the female parent having bisexual flowers, well before anthesis i.e. formation of pollen grains.  The bisexual flower of a female parent is emasculated. Buds are opened and stamens are removed mechanically by forceps or by giving hot water treatment.  Emasculation is done to prevent self-pollination.  Emasculation is done in the early hours of the morning.  Day, date, and time of emasculation recorded. 

 Crossing: 

Pollen grains are dusted on the mature stigma of an emasculated flower by opening the bag tempor It can also be done by brushing the pollens or pollen grains from the male parents directly on the stigma of the emasculated flower.  The date of crossing is recorded on the tag.  d Bogging and Tagging: Emasculated flowers are then bagged in polythene bags or sterile paper bags to prevent pollination by foreign pollens.  This is called bagging.  A 'tag' is tied to the bag.  The tag carries brief information about the names of selected parent varieties and the day, date, and time anthesis, emasculation, and 4107 Bagging and tagging