What are the techniques used for Hybridization?

Technique:

The techniques require skilled hands since the process involves the bringing of the stigma and poller of different plants together. Normally, the parents chosen for the cross are vigorous and healthy.

Having selected the male and female parent, the first step in hybridisation is to ensure that no pollination takes place before done artificially.

Emasculation:

This is a process where the anthers are removed physically in self- pollinated plants. In cases where physical removal is not possible, other methods are adopted.

These are dipping the panicle in hot water (50°c) for 10 minutes as practiced in Sorghum, or through chemical treatments like dichlorophenoxy acetic acid maleic hydrazide, as practiced for plants like wheat.

These methods ensure male sterility. Bagging: After emasculation flower buds are enclosed in bags to avoid getting pollers from undesired sources. Bagging is done with special paper or polythere but there should be complete protection to the flowers. After bagging, the emasculated flowers are labelled properly.

Artificial Pollination:

Pollens from the selected male plants are collected in suitable containers (paper bags, tubes or dishes) and then dusted with a fine brush, on to the receptive stigma of the female parent. After this, the female flower is securely sealed in a bag till the time of seed setting.

Rising of hybrids:

Seeds are collected from the fertilized plants and the F_i plants are raised. The F_i offspring’s are allowed to self-pollinate and seeds are again collected to raise F₂ generation. From the F₂ plants, the best plant is selected for its seeds to raise F₃ generation. The process is repeated till about Fi generation, because by that time the plants have become nearly homozygous for certain dominant genes so that the plants shall breed true for the desired traits.