Transgenic Breeding: Perspectives and Prospects

ABSTRACTTransgenic technology serves to introduce gene sequences for expression of a desired trait. Pro-duction of transgenic plants is reported in many crops, but commercialization is limited to a few selected crops, such as cotton ( Gossypium hir-sutum L.), corn ( Zea mays L.), soybean [ Glycine max (L.) Merr.], and canola ( Brassica napus L. and B. rapa L.). This paper presents the sequen-tial processes of transgenic event design, event selection, and “cleaning up” genetic background for forward breeding programs. Expression of the foreign gene cannot be viewed in isolation and is more complex than has been assumed because of the interaction of transgene with native genes. Variations among clones and within the progeny are observed, and hence all the clones are taken into account for evaluation. Plant breeding must be involved to move trans-genes from transformable but agronomically unacceptable genotypes into elite breeding lines with two backcrosses. Production of transgenic plants in large numbers is diffi cult and laborious and requires large investments. It is worthwhile investing in parallel efforts to incorporate the transgene into improved plant material to satisfy commercial interests.National Research Centre for Sorghum (NRCS), Rajendranagar, Hyderabad 500 030, A.P., India. Received 3 Oct. 2008. *Correspond-ing author (visarada@nrcsorghum.res.in).