Plant biotechnology spans a broad and rapidly expanding range of research techniques aimed at direct control over the genetic make-up of crops through the manipulation of plant cell cultUres and through the analysis and isolation of DNA. The most common applications of biotechnology to plant breeding can be separated into five broad categories: tissue culture, DNA marker technology, genetic engineering, genomics and bioinformatics. Tissue culture involves in vitro regeneration of whole, functioning plants from single cells or small portions of parent plants. Marker technology allows many of the loci, genes, and alleles that are important in crop improvement and already present in the gene pool available to breeders to be identified, located on the chromosomes, and more effectively transferred via conventional crossing. It enables interactions berween genes to be determined and facilitates the identification and use of new favourable alleles from wild relatives. Its most useful form, marker-assisted selection (MAS) involves whole-plant selection based on DNA markers closely linked to genes of interest. Genetic engineering refers to the in vitro transfer of genes into plant cells followed by regeneration of whole plants containing these genes in the germline (Hoisington et aI., 1998). As laboratories become more fluent with biotechnology methods of research, these three areas are increasingly being used in synergistic combination with each other.
More recently, a new application of biotechnology, termed 'genomics', has evolved out of work in molecular genetics. Plant genomics can be described as identifying the function of all of a plant's genes and how they work together to determine when, where, and why traits are expressed. Using gene chip (the plotting of thousands of gene segments on plates or 'micro-arrays') technology the interrelationships and interactions berween genes and whole pathways can now be studied, and should help breeders to create varieties with more exact combinations of desired traits (Wang et al., 2000). Such aims have been facilitated in part by the development of methods for isolating 'expressed sequence tags' - short segments of gene transcripts, which have been sequenced and can be used to help identify the level of expression and function of the genes that generated them. Because gene-encoding sequences represent only 10% of most genomes, this method allows researchers to concentrate on the more informative ponions of genomes. The international effort currently under way to sequence the entire rice genome as a model cereal genome should be completed in 2 to 3 years. It is already generating full sequence data and is providing a wealth of useful new information for genomics research. Because the genes that code for numerous plant traits and processes are quite similar across species, this knowledge can be applied to genetic research on other crops. It is widely believed that genomics will eventually replace the comparatively imprecise method of identifying genes through markers, which usually do not identify the gene itself.
Stemming from the explosion of information on plant genomes, yet another new application, that of bioinformatics, has become of primary importance. Bioinformatics, as the term implies, is essentially the management of information on gene structure, position and function in ways that allow the data to be used to make broader interpretations related to the behaviour of whole organisms. Since cereal genomes are very similar in gene content and gene order, bioinformatics should facilitate comparisons and sharing of information across crop species. This, combined with the fact that bioinformatics requires powerful computational capabilities, sophisticated software, networking, and specialized human resources, argues in favour of having bioinformatics centres that work on several crops. Together, genomics and bioinformatics are aimed at eventually allowing researchers with access to the information to understand the functioning of whole genomes.
Leading academic researchers are interested in research competitiveness. They readily sign research MTA's to keep competitive but are then restricted from further transferring their research products. Their universities now have 'technology transfer offices' where the incentives are to maximize IP royalty income, often by granting exclusive licenses. The net result is that improved plant materials produced by academic scientist- inventors are highly IP-encumbered abnd commercially useful only to a big company having an IP portfolio large enough to cover most of the IP constraints. The international agricultural research system does not have such an IP portfolio and as a consequence the traditional flow of materials through the system is breaking down, particularly at the point where useful new technologies and improved plant materials flow from public sector researchers in developed countriesto international centres and national crop improvement programmes in developing countries.