The recently developed technologies of genetic engineering offer the plant scientist not only a number of opportunities for introducing valuable novel characteristics into some of our crop plants but also provide for the first time the means to analyse and dissect some of the complexities of plant development and metabolism, and which will ultimately lead to even greater contributions to plant science.

At present the technology is still in an early phase of development. Methods of isolating particular genes and regulatory sequences are accelerating rapidly, as are the means of modifying them prior to their reintroduction into plants; the ability to culture cells and tissues in vitro are well established for a great number of species. Introducing the genes into plants cells is relatively easy for some species but remains very difficult as yet for others, including some of our most important crop plants; regenerating whole plants from cultured cells and tissues is similarly easy for some but difficult for others. However even at this early stage there are some remarkable achievements; the production of herbicide resistant plants by incorporating genes either from bacteria or from unrelated plants is one. Resistance to particular insects has been achieved by again incorporating a gene from a bacterium which codes for a toxin or one from a plant which codes for a naturally occurring compound toxic to insects. An achievement which may have even greater potential is that of the production of virus resistant plants; this is achieved by incorporating a part of the virus’ own genetic information into the plant. These achievements are already nearing commercial exploitation in some instances.