Somaclonal variation in plants refers to the genetic variation that occurs among plants regenerated from somatic (non-reproductive) cells that have been cultured in vitro (in tissue culture).
In simpler terms, when plants are grown from cells or tissues in a laboratory through tissue culture, some of the new plants may show differences from the parent plant. These differences are called somaclonal variations.
Causes of Somaclonal Variation
- Chromosomal changes – such as deletions, duplications, or rearrangements.
- Gene mutations – small changes in DNA sequences.
- Epigenetic changes – alterations in gene expression without changing DNA sequence.
- Stress in tissue culture conditions – like hormones, chemicals, or prolonged culture time.
Examples of Somaclonal Variation
- Variations in plant height, flower color, leaf shape, or fruit size.
- Development of disease-resistant or stress-tolerant plants.
Applications
- Crop improvement – to produce new traits such as pest or disease resistance.
- Micropropagation – sometimes used deliberately to create variation for breeding.
- Genetic studies – helps understand how genes and chromosomes behave under stress.
Example
In sugarcane and potato, somaclonal variation has been used to develop plants resistant to diseases and environmental stress.
In summary:
Somaclonal variation = Natural genetic variation that arises during plant tissue culture, sometimes useful for plant breeding and crop improvement.