Get complete information on Mutation Breeding

Mutation:

Sudden, stable discontinuous and inheritable variations which appear in organism due to permanent change in their genotype.

Spontaneous mutation:

Mutations which occur naturally, i.e., both germinal and somatic.

Induced mutations:

Mutations produced in response to a treatment with a mutagen. They were first produced by Muller (1927) with the help of X-rays on Drosophila and by Stadler in maize.

Mutagens:

Rate of mutations is increased by means of certain factors and chemicals called mutagens. 2 types:

(i) Chemical mutagens:

A variety of chemicals like ethylmethane sulphonate (EMS) and sodium azide which induce mutations.

(ii) Physical mutagens:

Various kinds of radiations e.g., X-rays, gamma rays, ultraviolet rays etc.

Mutation can arise due to a change in any of the following:

(i) Chromosome structure

(ii) Chromosome number

(iii) Base sequence of the concerned gene.

Mutation breeding:

The use of induced mutations in plant breeding to develop improved varieties. In such breeding usually seeds are treated with a suitable mutagen. The treated seeds are grown in the field and self-pollinated. Progeny from these plants are grown during the next crop season.

These plants are carefully observed to identify and select mutations of interest. In the end, a desirable mutant line may be obtained which may be good enough to be released as a new variety. Over 200 varieties have been produced from mutation breeding in India.