GENETIC-IMPLICATIONS OF SOMACLONAL VARIATION IN PLANTS

This chapter discusses the genetic implications of somaclonal variation in plants. The chapter investigates the topic of somaclonal variation from two perspectives. The first perspective is an examination of the various categories of somaclonal variation and speculation on the underlying mechanisms, including a discussion of how seemingly unrelated phenomena may be interconnected. The second perspective is a description of the unusual genetic outcomes that would be predicted, and the implications of these types of variation for use of tissue culture-derived materials. Emphasis could be placed on the genetic changes that may be detected in regenerated plants and their progeny because these genetic changes are of utmost practical significance. Throughout the chapter, “somaclonal variation’’ is taken to mean any genetic, cytogenetic, or molecular changes produced during tissue culture or plant regeneration. Changes detected in the sexual progeny of regenerated plants are often considered to be “stable,” and contrasted with the “epigenetic” traits that are sometimes detected in tissue cultures or primary regenerants. © 1992, Academic Press Inc.