What are the causes of somaclonal variation?
Cause of Somaclonal Variation The somaclonal variation developed due to physiological activity such as plant hormone, plant growth regulators, and culture conditions of the media. This type of variation caused when the sample expose a longer time in a particular conditions.
In which of the following conditions do the somaclonal variation appear?
(d) Tissue cultured raise plants. It leads to genetic variation, which develops spontaneously in culture due to stress conditions. Complete answer: When explant develops from the non meristematic area then it leads to somaclonal variations which appear in tissue culture raised plants.
What is somaclonal variation?
Somaclonal variation is the variation seen in plants that have been produced by plant tissue culture. Chromosomal rearrangements are an important source of this variation. The phenomenon of high variability in individuals from plant cell cultures or adventitious shoots has been named somaclonal variation.
Is somaclonal variation heritable what are the factors that can induce somaclonal variations?
Larkin and Scowcroft coined the term “somaclones” for plant variants obtained from tissue cultures of somatic tissues. Several causes of this type of variation are heterogeneity between the cells and explant tissue, spontaneous mutation and activation of culture environment of transposition of genetic materials.
Which is somaclonal variation?
Somaclonal variation is the variation seen in plants that have been produced by plant tissue culture. Chromosomal rearrangements are an important source of this variation. The phenomenon of high variability in individuals from plant cell cultures or adventitious shoots is called somaclonal variation [13].
What are the limitations of somaclonal variation?
Limitations of somaclonal variation: Uncontrollable and unpredictable nature of variation and most of the variations are of no apparent use. The variation is cultivar dependent. The variation obtained is not always stable and heritable. The changes occur at variable frequencies.
What is the selection procedure for somaclonal variants?
Selection for herbicide resistant phenotypes among the somaclonal variants has also been made. The herbicide is generally added to the cell culture system and the regenerated plantlets showing the tolerance to herbicide are selected.
What are the types of somaclonal variation?
There appear to be two types of somaclonal variation: heritable and epigenetic. Heritable variation is stable through the sexual cycle or repeated asexual propagation; epigenetic variation may be unstable even when asexually propagated.
How is somaclonal variation induced?
Generation of somaclonal variations is attributed to genetic and epigenetic modifications in DNA. In particular, transposable elements (TEs) are one of the causes of genetic rearrangements in in vitro culture. Tissue culture is reported to activate silent TEs, resulting in somaclonal variations [3].
Which is a possible mechanism for somaclonal variation?
DNA sequence amplification could be one of the mechanisms responsible for somaclonal variation. Such amplification could lead either to increased synthesis of a specific gene product or to perturbations in developmental timing of gene activity if the repeat sequences function in new chromosomal locations.
What does Larkin and Scowcroft mean by somaclonal variation?
Somaclonal variation The term somaclonal variation by Larkin and Scowcroft (1981) was given for the variability generated by the use of a tissue culture cycle. Somaclonal variation is defined as genetic variation observed among progeny plants obtained after somatic tissue culture in vitro.
Why are somaclones different from the stock plant?
Some, or all, of the somaclones may be physically different from the stock donor plants [8]. Usually, variability occurs spontaneously and can be a result of temporary changes or permanent genetic changes in cells or tissue during in vitroculture.
Which is the best fruit to study somaclonal variation?
Sweet orange and other polyembryonic citrus cultivars are well suited for studies of somaclonal variation due to their biology and good performance in tissue culture. The sweet orange is polyembryonic and forms adventive somatic embryos from nucellar tissue]