PLANT BREEDING Plant Biotechnology & GMO’s

THE ROLE OF PLANT BIOTECHNOLOGY IN FOOD PRODUCTION Biotechnology involves the use of scientific methods on organisms to produce new products or new forms of organisms.

Plant physiologists work with genetically engineered alfalfa. Photo by Bruce Fritz courtesy of USDA Agricultural Research Service. Modification of organisms involves plants, animals, and microorganisms, such as bacteria and viruses.

Pictured are crops that have either already been genetically altered or are involved in research for genetic alterations. Photo by Stephen Ausmus courtesy of USDA Agricultural Research Service. Genetically altered organisms are referred to as Genetically Modified Organisms or GMOs

Genetic engineering allows scientists to physically remove the DNA from one organism and transfer gene(s) for one or a few traits into another organism. Traditional plant breeding methods, such as crossing, are not necessary when using genetically modified organisms.

The two main areas of biotechnology are:  Organismic Biotechnology  Molecular Biotechnology

Organismic biotechnology alters or improves intact organisms, but does not physically alter the natural genetic material of the organism.

Molecular biotechnology involves the alteration of naturally occurring genes of an organism to achieve specific outcomes.

Transgenic organisms are those produced when genes within the cells of those organisms are artificially altered.

These tomatoes were genetically engineered to improve phytonutrient content and longevity of fruit. Photo by Scott Bauer courtesy of USDA Agricultural Research Service. Genetically modified organisms are being created for use in many areas of agriculture, medicine, environmental protection, engineering, food products, industry, and manufacturing.

METHODS OF GENETIC ENGINEERING IN CROPS Genetic alteration and engineering of crops used for food is a long and intense process that involves many scientific disciplines. Bt corn is an example of a genetically engineered crop.

One method of producing a genetically modified crop includes:  Isolating an organism with a specific desirable trait and extracting its DNA  Cloning a gene that controls the trait  Designing the gene to express in a specific way  Transformation, or inserting the gene into the cells of a crop plant (this process is aided by the use of tissue cultures)  Plant breeding through backcross breeding methods to get the transgene into an elite background.

Scientist working with tissue culture of wheat to develop Fusarium head blight resistant plants. Photo by Jack Dykinga courtesy of USDA Agricultural Research Service.

Over 100 years ago, scientists discovered a bacterium (Bacillus thuringiensis, or Bt) naturally located in the soil which produced a protein that was toxic to various types of worms. Scientists learned how to extract the DNA from the bacteria, isolate and clone the gene that produces the bacteria, design the DNA code to produce the protein in the green tissues of the corn plant at a level lethal to the European corn borer.

Backcross plant breeding combines the desired traits of elite parent plants and the transgenic parent plants into a single line. The offspring of the two parent lines are repeatedly bred back to the original elite parent line to produce a transgenic line with high-yielding elite line characteristics.

The end product becomes a transgenic plant with a yield potential that is similar to that of traditionally bred hybrid plants.

Two reasons for genetically engineering food crop plants include:  Producing food for an ever increasing world population  Producing large quantities of high quality raw foods with a minimum impact on the environment