Hint: Limitations of mutation breeding include pleiotropic effects, low frequency, lethal mutations, undesirable side effects, difficult selection process etc.
Complete answer:
The utilization of induced mutations in crop improvement is called mutation breeding. The main limitations of mutation breeding for crop development are as follows:
> Large doses of mutagens are needed for mutation breeding of polyploidy species and it is often difficult.
> Mutations often produce pleiotropic effects.
> Frequency of occurrence of desired mutants is usually low.
> They may affect the viability of the crop variant.
> Lack of detailed information on mutagens makes mutation breeding an inappropriate method for crop improvement.
> At times, certain mutations are harmful for the organism and are known as lethal mutation.
> The large population of crops must be screened to select the variants with desired mutations. This process is often tedious and time consuming.
> Certain crops with desired mutation may show undesirable side effects.
> As most of the mutations are recessive, the detection of clonal crops with recessive mutation is difficult due to the dominance of its allelic counterpart.
> Registration of the mutant variety for commercial use may be problematic in many parts.
Additional information:
In 1901, Hugo De Vries first identified mutation as an appropriate heritable mechanism of creating variability in evening primrose (Oenothera lamarckiana). Mutation breeding, often known as “variation breeding”, is a process of exposing seeds to chemicals or radiation which act as mutagens in order to develop mutants with desired traits to be bred with other cultivars. Such mutant plants are known as mutagenic plants.
Note:
In recent decades, tremendous progress in the field of mutation breeding has provided breeders better knowledge of induced mutation for crop improvement. New development in plant mutation research for crop improvement include fundamental studies of mutagenesis to reverse genetics.
