Induced Mutations for Developing New Ornamental Varieties

Abstract

The ornamental plant industry is a dynamic and diverse sector worldwide. Plant breeders develop a great number of new cultivars each year to increase production and supply market demands of the ornamental plants. Mutation breeding is a highly effective method for creating genetic variability in ornamental plants with desirable characters expected within a given species’ genetic scope. A mutation creation is called induced mutagenesis of which results are varied according to mutagens and the type of the technique and it is a random process. The target-selected mutagenesis including the random mutagenesis and selection of mutants at a selected locus belongs to this category. By the present, mutations were induced by treatments with physical and chemical mutagens and sometimes their combination. However, biotechnological approaches such as transposable elements, disrupting the gene through the insertion of a DNA fragment and using molecular techniques to create a mutation at a defined site in a DNA molecule have been used to obtain mutations since the development of recombinant DNA technology. There are about 720 ornamental mutant cultivars developed by mutation breeding studies that have been accelerated with tissue culture techniques since the 1970s. In vitro mutagenesis provides for the isolation of chimeric tissues and the propagation of irradiated tissues in mainly vegetatively propagated plants. In addition, in vitro techniques can be supported to the breeding program before, after, and during the mutagen treatments, allowing the scientist to perform the studies timeless and independently of environmental conditions. In vitro techniques have been commonly used in mutation breeding since in vitro technologies were extensively developed. This chapter presents a brief history of mutation breeding in ornamentals and in vitro mutagenesis strategies in ornamental plants.