Use of Cell Culture in Mutant Selection - An important use of cell cultures is in mutant selection in relation to crop improvement. The frequency of mutations can be increased several fold through mutagenic treatments, and million of cells can be screened. Since selection of mutations will be exercised at cellular level, no chimeras will be obtained, which is sometimes a drawback of mutation breeding methods, where mutants are selected at the level of whole plants.

Further if haploid cells (like micros pores) are used for cell culture, the problem of dominance not permitting the expression of mutation in Ml generation is also automatically overcome.

Salt tolerant and cold tolerant cell lines have also been isolated in the genus Nicotiana. Auxotrophic mutants are selected by microbial methods using the 'minimal medium, where only prototrophs will grow. The cell lines will be grown first on the minimal medium. Lack or' growth on minimal medium will suggest the presence of an auxotroph, which can be grown on supplemented media to identify nutritional deficiency.

The selected mutant cells need to be grown into whole plants, which will be multiplied and tested for the mutant phenotype. This mutant phenotype mayor may not express at the level of whole plants. If it expresses in whole plant, its genetics can be studied using conventional methods of genetics.