Applications of Mutation Breeding
Mutation breeding has been used for improving morphological and physiological characters, disease resistance and quantitative characters including yielding ability. The various applications of mutation breeding are as under.
- It is useful in improving certain specific characteristics of a well adapted high yielding variety. This is particularly useful in floricultural crops which are mostly clonally propagated. These crops show highly heterozygous nature and therefore, in such a case, mutagenesis is the only method available to improve the specific characteristics of clones without changing their genetic makeup.
- Inductions of desirable mutant alleles which may not be present in the normal population or germplasm or may be present but may not be available to the breeder due to political or geographical reasons.
- Mutation breeding can also be used on F1 hybrids or progenies resulting from inter-varietal crosses. These may be treated with mutagens in order to increase genetic variability by inducing mutations and to facilitate recombination among linked genes.
- Irradiation of inter-specific (distant) hybrids has been done to produce translocations.
Limitations of Mutation Breeding: The experience with mutation breeding has brought out certain limitations
- Mutation is a process that results in the individual with desirable or non desirable characteristics. The frequency of desirable mutations is very low, about 0.1 per cent of the total mutations. Therefore, large M2 and subsequent populations have to be grown and carefully studied. This involves considerable time, labour and other resources.
- The breeder has to screen large population to select desirable mutations. Therefore efficient, quick and inexpensive selection techniques are required to screen large populations.
Development of cultivar through spontaneous mutation in floricultural crops:
- Variety 'Pusa Tara': Spontaneous mutant of Coreopsis
Development of cultivars through physical mutations in floricultural crops :
- 'Los Banos Variegata': Gamma-ray induced mutant of multibracted bougainvillea cultivar 'Los Banos Beauty'
- 'Los Banos Variegata Silver Margin': Gamma-ray induced mutant of multibracted bougainvillea cultivar 'Los Banos Beauty'
- 'Mahara Variegata': Gamma-ray induced mutant of multibracted bougainvillea cultivar 'Mahara'.
- 'Shobha': Induced mutant of 'Wild Rose'
Development of cultivars through chemical mutations in floricultural crops:
- Los Banos Variegata 'Jayanthi': Ethyl Methane Sulphonate (EMS) induced chlorophyll variegated mutant of bougainvillea cv. 'Los Banos Beauty'.
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Last modified: Tuesday, 7 August 2012, 9:38 AM