A genetically engineered organism or a transgenic is one in which genes or the hereditary material which determines the characteristics of the organism is transferred from one organism to another through artificial means, either within species or between species. Genetically modified products are those that are obtained as a result of such efforts. These offer tremendous potential since a desired trait from one species, for example, a microbe, can be transferred to a plant or an animal and vice versa.

There are innumerable potential applications in health care, agriculture, industrial and environment sectors. The demand for GMOs in India by 2000 AD is estimated to be US $1,850 million according to P K Ghosh of the DBT and for the European Union (EU) by the year 2002 it is pegged at US $278 billion. Therefore the stakes are high with heavy investments and even higher expectations on returns.

At least 64 commercially important species have been used for incorporating transgenic traits. Important among these are maize, soybean, cotton, tomato, potato, alfalfa, petunia, rice, wheat, barley, beet, rape or mustard, cabbage, Bengal gram, and tobacco (See table Hot plants ). Among the six desired traits herbicide tolerance heads the list. Roundup ready soybean and cotton for instance are resistant to the herbicide glyphosate, a weed-killer.

Other traits include, insect resistance, viral disease tolerance, fungal disease tolerance, product quality improvements, and production of speciality products like chemicals. Plant genes such as cotton, maize and potato contain a gene from the microbe Bacillus thuringiensis ( Bt ). Transgenic plants harbouring this gene express or produce insecticidal proteins called Bt toxins that are capable of killing undesired pests. It is estimated that Bt biotechnology would annually generate business worth US $2.7 million worldwide. Environmentalists fear that pests will soon develop resistance to Bt, thus requiring more and more sprays. Besides, Bt is also used as a spray by organic farmers, who may face a problem if the pests develop resistance.

The area under cultivation is increasing in leaps and bounds. In 1996, five million acres were under cultivation in the US. In 1997, the figure rose to 23 million acres, and 30 million acres for the whole world. The crops cultivated in these areas include soybean, cotton, potato and mustard.