ABSTRACT
Transformation is the process of introducing DNA into cells. Genetic manipulation techniques allow scientists to isolate a single DNA sequence from one organism and join it to that of a completely different organism to form what is now known as recombinant DNA. When a particular DNA sequence is to be transformed into a living cell, it is first inserted in a vector. Vectors are used to assist in the transfer, replication, and sometimes expression of a specific DNA sequence in a target cell. This chapter discusses several different approaches since developed for the transformation of vascular plants. It describes the most widely used system, which is based on the Agrobacterium tumefaciens tumor-inducing (Ti) plasmid. The chapter then illustrates Agrobacterium-mediated transformation systems. Two strategies have been developed for using Ti-based plasmids: a methodology called cointegration and the binary vector system. Plant viruses have several special features as potential vectors for plant genetic engineering.
