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.
“When you actually look at the top 10 fruits in the world, six of the top 10 are convenience products,” says Lain Jager, chief executive of Zespri Group Ltd., the world’s biggest exporter of kiwis. “Having a kiwifruit that you could eat in a convenient way would be fantastic.”
I was surprised that it was only 6. It’s hard not to imagine that meeting the consumer’s demand for convenience will be a precondition for the success of any fruit in the future. Berries less perishable. Melons yielding more more flesh per skin for salads. The peels of handheld fruits must be edible or peelable without a tool or juicy mess.
Good news for picky kid, travelers and those that pack lunch bags. Bad news for gourmands.
Here’s a question. People often, naively I think, hold that we have long and comforting experience with selective breeding and do not to worry about testing new crops. It’s the novelty of transgenes that they worry about. We don’t know enough about the potential human health and environmental problems that could arise from these novel genetic combinations that we have little experience with.
And yet if a plant breeder chose to cross breed a wild relative with a plant in order to confer a desired trait of hardiness; drought, heat, flood, pest resistance – take your pick; nobody raises an eyebrow. Keep in mind that we have no experience eating the wild relative, no mandated testing of toxins (which of course would be the desired trait in breeding pest resistance) or allergens. We have no experience with large scale cultivation of the wild relative, so it’s hard to extrapolate the environmental impact.
So why doesn’t this keep you up at night?
Well it should’t, but you might ponder them next time the thought of a new genetically engineered crop has you quaking in your boots.