The Art & Science of Crop Improvement
A breeder is interested in crossing different species and often genera to combine desirable characters to produce commercially ‘superior’ varieties. This is one of the major approaches to crop improvement.
The Golden Rule: Ensure only the desired pollen grains are used and the stigma is protected from contamination.
If the female parent produces unisexual flowers, no emasculation is needed.
The flower buds are simply bagged before they open. When the stigma becomes receptive, pollination is carried out.
Required for Bisexual Flowers.
Removal of anthers from the flower bud before the anther dehisces using a pair of forceps. This prevents self-pollination.
Emasculated flowers are covered with a bag of suitable size, generally made of butter paper.
This prevents contamination of the stigma by unwanted pollen.
When the stigma attains receptivity, mature pollen collected from the male parent is dusted on the stigma.
The flowers are rebagged, and the fruits are allowed to develop.
The father of genetics, Gregor Mendel, utilized these exact techniques of Artificial Hybridization on garden peas (Pisum sativum).
By carefully emasculating the bisexual pea flowers and manually dusting them with pollen from specific parents, he ensured that his cross-pollination experiments were controlled. This rigor allowed him to formulate the fundamental Laws of Inheritance.