Improving the characteristics of a plant like this brussels sprout used to depend on selective breeding and lots of time, until chemical engineers helped speed up the process. Courtesy Andrew Davis, John Innes Centre.
Plants that have been modified genetically may be used to produce crops with
- Higher nutritional content,
- Greater resistance to herbicide and pesticide damage,
- Increased resistance to disease,
- Specific desirable traits (e.g., faster ripening or delayed softening), and
- Reduced allergenicity.
Genetic modification is a technique for changing the characteristics of a plant or organism to produce more desirable traits. For many years these changes were done by natural selection. Now genetically modified foods are produced using an artificial form of DNA called recombinant DNA (rDNA). In simplest terms rDNA with a positive trait is transferred into an organism lacking that trait to create the desired improvement.
Longer-lasting tomatoes
The first agricultural product produced in the United States using rDNA was introduced in the 1990s. It was a plant that produced tomatoes with a longer shelf life. The plant was genetically modified to produce less of the enzyme that causes tomatoes to ripen and soften. Since then many other rDNA-modified crops—fruits, vegetables, and grains—have been introduced with improved traits.
Predictable results
Historically, researchers introduced desired traits into plants by crossbreeding over multiple generations. This relatively hit-or-miss approach took a long time. By comparison, genetic-modification techniques allow researchers to identify one or more genes responsible for a particular trait and then insert them into a plant with greater speed and precision. The end result is highly predictable.
Future goals
Chemical engineers continue to work with food scientists and biotechnologists to develop more advanced techniques to transfer genetic materials from one organism to another. Genetic modification of foods is one of the most promising and safest strategies available to increase total global food production, reduce crop losses, and increase nutritional content.
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