Hybridization techniques

the five main steps of hybridization technique. The steps are: 1. Selection and Preparation of Parents 2. Emasculation 3. Bagging 4. Pollination 5. Selection. (Hkaravalli.com)

Hybridization Technique # Step 1. Selection and Preparation of Parents:

The plant breeder must have a clear idea about the plants which he wants to use as parents — a subject which may be called crop botany. The time of flowering, the stage of flower development at which the anthers burst (anthesis) and the stigmas become receptive and also the time period for which the pollens remain viable and the stigmas remain receptive must be known beforehand.

Crop plants are mostly annual plants and in such plants the pollens remain viable for several days after anthesis, and so pollen viability is not a critical factor. But in annuals stigmas remain receptive for a short period, 

Hybridization Technique # Step 2. Emasculation:

At a certain stage of flower development the anthers become ripe and dehisce to liberate the pollens. This is known as anthesis. These anthers must be removed before anthesis from the flowers of the female parent to prevent self-pollination. This is called emasculation. Fig. 4.1 shows the plant breeder’s kit which is specially needed for emasculationHybridization Technique #

 Step 3. Bagging:

The emasculated flowers should be kept properly covered so that no untoward cross-pollination takes place. This is done by enclosing the emasculated flowers in muslin, oil paper or polythene bags (Fig.S   tep 4. Pollination:

When the stigma of the emasculated flower becomes mature (receptive) it is artificially pollinated by pollens taken from the male parent. During pollination whole, freshly dehisced anthers are plucked from the flowers of the male parent by means of forceps (then sterilized with rectified spirit) and dusted on the stigma. The bags are temporarily removed at the time of pollination and replaced, as before, after pollination.The crossed flowers should always be kept properly tagged or labelled. Fine, rectangular and thin sheets of aluminium make good tags.

Hybridization Technique # Step 5. Selection:

The seeds are allowed to mature within the bags. They are then harvested and stored with proper labelling. From the next growing season onwards the hybrid seeds are grown, allowed self-pollination and selection is carried on to find out the desired phenotypes and make them homozygous.Section can be done following the Bulk Method or the Pedigree Method. Selection is followed by field trial and then only it can be recommended for large scale cultivation.