Submitted to: Crop Science
Publication Type: Review Article
Publication Acceptance Date: 1/30/2006
Publication Date: 7/25/2006
Citation: Jauhar, P.P. 2006. Modern biotechnology as an integral supplement to conventional plant breeding: the prospects and challenges. Crop Science 46:1841-1849. Interpretive Summary:
Technical Abstract: The art of plant breeding was developed long before the laws of genetics became known. The advent of the principles of genetics and cytogenetics at the turn of the last century catalyzed the growth of plant breeding, making it a science-based technology that has been instrumental in bringing about substantial genetic improvements in crop plants. Largely through exploitation of hybrid vigor, grain yields of several cereal crops were substantially increased. Intervarietal, interspecific and intergeneric hybridizations, coupled with appropriate cytogenetic manipulations, proved useful in moving genes for resistance to diseases and insect pests, and abiotic stresses from suitable alien donors into crop cultivars. The process of plant improvement has been further accelerated by biotechnological tools of gene transfer, which help engineer new traits into plants that are otherwise very difficult to introduce and evaluate by traditional breeding. Most major crops are being genetically transformed by direct DNA delivery via microprojectile bombardment or other means. The successful deployment of transgenic approaches to combat insect pests and diseases of important crops like rice, wheat, maize, barley and cotton is a remarkable accomplishment. Biofortification of crops for alleviating malnutrition among the poor constitutes another exciting development in tackling the problem of global hunger and malnutrition. Golden rice, which is genetically enriched with vitamin A and iron, has, for example, the real potential of saving millions of lives in impoverished countries. Such a nutritional enhancement of a cereal crop would be unimaginable by conventional means. Yet another exciting application of transgenic technology is in the production of edible vaccines for immunization against deadly diseases like hepatitis B or tuberculosis, some of the serious diseases of the poor in Africa and Asia. In addition to all these applications, there are some novel applications of transgenic technology, e.g., for producing decaffeinated coffee. How these in vitro approaches to gene transfer can effectively supplement the conventional breeding programs will be described. When carefully deployed as a supplement to conventional breeding, the new technology could play a significant role in bringing about imporvement of crop plants.