Mechanisms of somaclonal variation

Abstract

Although plants derived from tissue cultures are the product of asexual reproduction they may show considerable phenotypic and genotypic variability, or “somaclonal variation This review describes our current understanding of the underlying mechanisms involved. It appears that somaclonal variation is a complex phenomenon which results from a multiplicity of cellular and genetic mechanistns. A number of key processes are discussed-(1) upset of the stabilising influences normally associated with organised growth, (2) loss of control of the mitotic cycle in vitro, (3) genomic changes which occur during differentiation and de-differentiation, (4) the influence of growth regulators and (5) genome instability under stress. © 1993 Taylor & Francis Group, LLC.