Group Hybrid Method
In controlled pollination when it is desired to exclude unwanted po11ens it is necessary to remove the anthers of the flowers (emasculation) at the time of flower opening. A thin cloth-bag or perforated polythene bag may be placed over the emasculated flower and tied with a string around the base to prevent the entrance of insects that might carry unwanted pollen to the stigma. When the stigma becomes receptive in 3 days from flower opening the bags should be removed from the emasculated flower and the selected pollen applied to the stigmatic surface.
This may be done with the help of a fine camel-hairbrush. A little quantity of the stored pollen may be collected at the tip of the brush and the pollens gently brushed on the surface of the stigma. A label indicating the names of the parents should be used and the bag replaced over the pollinated flower and tied as before. As soon as the flower starts withering, the bag should be removed permanently. Success in crossing is indicated by the swelling of ovary and formation of fruit (a 3 -celled capsule) which ultimately ripes with 20- 25 days after pollination. When the fruits ripe they become yellowish in colour. Care should be taken to collect the mature seeds, otherwise seeds shatter after the fruits burst open. The flat, winged seeds should be air-dried. Seedlings are raised by sowing the seeds in beds or pot which usually flower within 2 to 3 years.
B. Mutation
The hereditary make up in the cells may change due to crossing over, translocations, deletions in chromosome number and due to change of gene in quality or kind in chromosomes. Thus, the new variants are created as a result of mutation.
1. Natural or spontaneous mutation
This may occur in any cell and at any stage. There is an immediate effect of the mutation arid its ability to produce phenotypic change as determined by its dominance. The spontaneous mutations are rare
2. Induced mutations
Induced mutation has been derived by use of physical and chemical mutagens. It has been reported that the frequency of structural rearrangements such as translocations between chromosomes can be increased by x-ray treatment. The effect of irradiation is found to be destructive as a result of curled leaves.
Certain chemical agents have also been shown to increase the mutation rate. Most chemical mutagens identified, seem to have a general effect like irradiating agents. No specific chemical reaction seems to explain the increase in mutation rate.
C. Polyploid breeding
Polyploidy has been an important means of improvement and some of the species of amaryllis evolved are tetraploid of particular interest are the triploid hybrids which were outstanding and surpassed both diploid and tetraploids in all floral characters.
Next : Propagation of Amaryllis Plants and Hippeastrum

