In the News
Classical Plant Breeding (Traditional) and Genetic Engineering – A Primer
Traditional plant breeding: One of my jobs in the late 1960’s was to take a small piece of 200 grit sandpaper folded into a small pointed trough and collect the pollen (male flower part) from certain alfalfa plants. I then transferred this pollen to the pistil (female flower part) of another alfalfa plant. The resulting seed produced was then evaluated to see if it had nematode resistance, first in the greenhouse, then in field plots. The traditional breeding process can take 10 years or more to cross plants and select a good variety. In other plants, crosses are made using paint brushes and tweezers to physically transfer pollen from one parent to another parent to try to combine desirable characteristics of each parent into the progeny (babies). Luther Burbank (1849-1926), the famous plant breeder/botanist, developed over 800 different varieties of fruits and vegetables using classical plant breeding methods.
Genetic Engineering (GE) and GMO: In the 1980’s, scientists in a laboratory were able to introduce a reverse-orientation copy of an “antisense” gene in a tomato (sort of taking out a gene in the chromosome and putting it back in backwards). This slowed the ripening of the tomato which increased the shelf life dramatically. In 1994, the FLAVR SAVR tomato was released to the public. Calgene, the company marketing this tomato and tomato paste products, met with resistance from consumers and retailers in the United States and the United Kingdom and soon after the tomato was deemed ‘not profitable’ and the project stopped.
Today, several products have been commercialized using GE techniques including insect-resistant varieties of cotton and corn, herbicide-tolerant soybean, corn, canola, and alfalfa, and virus-resistant papaya and squash. Over 93% of the soybeans grown in the United States have been engineered to be herbicide tolerant (the herbicide being Glyphosate, also known as Roundup®). Introducing new genes into plants can involve using the same kind of plant, a different plant, or a different organism, such as a microorganism. In classical breeding, thousands of genes are being rearranged, whereas GE involves the specific handling of single genes (using “chemical scissors”). The genes used in GE can come from any organism, and the genes in classical breeding must be very closely related. The current controversy is whether GMO foods should be labeled so that the consumer knows what they are buying (Proposition 37 in California).
For more information on this subject I refer readers to several good websites, http://ucbiotech.org and http://www.cera-gmc.org/?action=gm_crop_database .