By inserting the PAT gene into plants, they are able to produce the PAT enzyme and become resistant to Liberty. The biotech companies tout the crops as offering farmers higher yields, convenience and crop safety. Roundup Ready seeds, like LibertyLink ones, also guarantee a market for Roundup herbicide. This also saves farmers money by eliminating the need for spraying combinations of herbicides throughout the growing season that each only kill a limited number of weeds. Roundup herbicide has been used commercially for more than 20 years and Monsanto s patent expires in 2000, which will open the market to other glyphosate-based competitors.
Soybeans can cross-pollinate with other members of the same genus, Glycine, which are found in Asia.
Herbicide tolerance was the dominant trait of 77 percent of the genetically engineered crops grown in 1998. Introduced in 1996, the use of Roundup Ready crops has already led to the emergence of weeds that are becoming tolerant to Roundup.