Somaclonal Variation: Its Genetic Basis and Prospects for Crop Improvement
Somaclonal variation is defined as genetic variation observed among progeny of plants regenerated from somatic cells cultured in vitro. Although theoretically all plants regenerated from somatic cells should be clones, a number of observations have indicated that this is not the case.1,2 In addition to the basic genetic implications of this phenomenon, the variation has proven useful in breeding programs of various crop plants.3 Conventional plant breeding has traditionally been the sole avenue for crop improvement; however, recent demands of agricultural-based industry has shown that this process is too time consuming for typical corporate time frames. While variability has been obtained from wild species of cultivated crops its access has been quite limited. Indeed many desired traits such as disease resistance have yet to be identified. It is also difficult to establish novelty related to legal protection of conventional breeding outputs since many workers are using the same breeding lines in their programs. Thus somaclonal variation provides great promise for reducing the time required to produce new varieties or breeding lines which are easily patentable due to their novel variation.
KeywordsBreeding Line Somatic Hybrid Somaclonal Variation Crop Improvement Plant Cell Culture
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