<P> Commercial sale of genetically modified foods began in 1994 , when Calgene first marketed its unsuccessful Flavr Savr delayed - ripening tomato . Most food modifications have primarily focused on cash crops in high demand by farmers such as soybean , corn , canola , and cotton . Genetically modified crops have been engineered for resistance to pathogens and herbicides and for better nutrient profiles . GM livestock have been developed , although as of November 2013 none were on the market . </P>
<P> Commercial sale of genetically modified foods began in 1994 , when Calgene first marketed its unsuccessful Flavr Savr delayed - ripening tomato . Most food modifications have primarily focused on cash crops in high demand by farmers such as soybean , corn , canola , and cotton . Genetically modified crops have been engineered for resistance to pathogens and herbicides and for better nutrient profiles . GM livestock have been developed , although as of November 2013 none were on the market . </P>
when were genetically modified crops first introduced for commercial production in the u.s
when were genetically modified crops first introduced for commercial production in the u.s
1994
1994