GUEST POST: Benjamin Edge
Benjamin Edge (@edgeben) is a former wheat breeder for Pioneer Hi-Bred, International, a DuPont Company, and for Clemson University. He has released 10 PVP protected wheat varieties and is a co-inventor of record for 5 wheat variety patents. He has taught classes in plant breeding, biology, and computer technology.
Transformation, the insertion of genes into an organism through the use of a ‘gene gun’ or a bacterial vector, is a tool used by plant breeders to introduce new traits to a crop when there is not enough readily useful variation present in the crop they are trying to improve. Transformation results in what we commonly refer to as genetically modified organisms, or GMOs. While some consider this a risky technology, transformation is actually very similar in effect to what conventional breeders do when they find a gene of interest in a wild relative, and use backcrossing to incorporate that gene into an adapted variety.
Backcrossing is a VERY effective tool of conventional plant breeders (Briggs and Knowles, 1977). Once you find a trait you are interested in, you can move that trait from a wild relative (closely related species) or from any member of the species you are working with into an adapted variety with great repeatability (reproduced or repeated easily). Backcrossing is used when you have a well adapted variety, say plant A, with high yield, large seeds, and strong stems, but with some weakness, such as susceptibility to a disease. If you find a plant, say plant B, with disease resistance, but poor yield, small seeds, and weak stems, you can use backcrossing to incorporate that disease resistance trait into plant A, what we call introgression of the trait.