Pollination - Artificial Hybridization

Artificial hybridization:

• A breeder is interested in crossing different species and often genera to combine desirable characters to produce commercially ‘superior’ varieties.
• Artificial hybridization is one of the major approaches of the crop improvement programme.
• In crossing experiments, it is important to make sure that only the desired pollen grains are used for pollination and the stigma is protected from contamination (from unwanted pollen). This is achieved by emasculation and bagging techniques.
• Emasculation is the process of removal of the male reproductive part (Anther) from a perfect (Bisexual) flower bud before the anther dehisces using a pair of forceps without damaging the female reproductive part (Pistil).
• Bagging is a technique used to prevent contamination of its stigma with unwanted pollen by covering the emasculated flower with a bag of suitable size, generally made up of butter paper.
• When the stigma of bagged flower attains receptivity, mature pollen grains collected from anthers of the male parent are dusted on the stigma, the flowers are rebagged, and the fruits are allowed to develop.
• Emasculation is not needed if the female parent bears unisexual flowers.
• The female flower buds are bagged before the flowers open. When the stigma becomes receptive, pollination is carried out using the desired pollen and the flower rebagged.