Genetically Modified Plants are Surrounded by Controversy and Promise

From the pages of Fine Gardening Magazine

Genetically Modified Plants are Surrounded by Controversy and Promise

Steve Silk ponders the implications of new trends in plant science

by Steve Silk

There's something about the bold new world of genetically modified plants that recalls a sideshow barker's pitch: "Step right up and see your wildest dreams made real. Pick a plant fantasy: a blue rose that smells like a banana. A peony that flowers from May to October. A tree form of forget-me-not." Genetic modification, or GM, may make it all possible.



Mark Brand, a University of Connecticut associate professor of ornamental horticulture, checks on the development of a batch of young genetically modified plants.

The science is evolving at an incredible pace, riding a wave of momentum begun by decoding the DNA of a simple weed, Arabidopsis, which is often called the fruit fly of plant genetics. Early genetic researchers used the model of the fruit fly, whose genetically simple structure and rapid life cycle surrendered its DNA secrets in a way complicated life forms did not, at least not as readily. Plant researchers exploring Arabidopsis have already uncovered loads of genes that may be useful in engineering new and better plants. It may show scientists how to turn on the process of flowering in a plant, and how to turn it off, or how to ensure that flowering is never turned off. It may show them how to make double flowers, fragrant ones, more colorful ones. It may teach them how to prevent a plant form from setting seed, so it can expend all its energy on producing luxurious flowers. Imagine what being able to control those qualities could do for the world of garden plants.

Never has there been such a promise for new plants, and in coming years, many of these will take the market by storm. One among who knows how many new hot plants is a blue carnation called Florigene Moondust. It was developed by a self-described "molecular breeding company" called Florigene, whose original mission was to create a blue rose. The door to the bounty of all this research is just now cracking open, but many fear it's more like lifting the lid on Pandora's box.

There are numerous possible perils to consider
The world of genetically modified plants is not just a bed of roses, or maybe it is. The subject poses countless thorny questions. Not since the power of the atom was unlocked at laboratories in Los Alamos, New Mexico, has humankind embarked on such a potentially dangerous voyage. Some fear that tinkering with DNA is perilously close to playing God. Who could guess what the future may hold for a world filled with rejiggered genes? The dangers are most clearly visible in food crops whose genetic structure has been altered. Here's an easy example: A flounder gene has been inserted into a tomato in hopes of producing a more cold-tolerant plant. But what if a man with a deadly allergy to fish unknowingly eats that modified tomato? Will he keel over and die? In all likelihood, the answer is no. But as the science evolves, who knows what unknown effects it may have on consumers?

Then there's the question of biodiversity. If a GM crop plant meets its promise, it would probably be grown all over the world. Old seed strains, the products of eons of evolution, might gradually disappear, and with them diverse and varying degrees of resistance to scourges such as drought, diseases, or pestilence. Without that genetic diversity, the new plants, grown in a worldwide monoculture, might be left dangerously susceptible to some disease or pest.

And then there's the well-founded fear that genes may escape from their hosts to infiltrate the DNA of other plants, leading to, well, who knows what? One dream of agriculturists is a Roundup-resistant plant crop, one that, by virtue of being impervious to the deadly effects of the herbicide Roundup, would greatly simplify the task of weeding. Spray everything, but only the unwanted plants die. It's been done successfully, and the so-called Roundup-ready gene was implanted in a rapeseed oil plant. But in a single season, the Roundup-ready gene made its way into the plant's pollen and escaped, via insect pollination, to a closely related weed whose offspring were -- you guessed it -- resistant to Roundup. In years to come, we may recognize that moment as the opening salvo in an ever-more-rapidly-escalating war pitting mutant plants against the increasingly powerful chemical arsenals developed by herbicide manufacturers.

To make matters worse, at least in my opinion, anybody with a couple hundred spare dollars and access to the Internet can buy everything they need to do his own backyard bio-engineering. It's like a comic book come-on: "Hey kids! Breed your own mutant plants at home!" Yes, it appears that just about anything really is possible when it comes to creating GM plants. Just think of the potential for havoc. I'm not about to provide as much as a single clue as to how to go about it.

Many can recall the chamber of horrors unleashed upon humanity after Pandora opened her mythological box, but few know that at the bottom of the box lay hope. So for now, I regard the brave new world of genetic modification with a cautious optimism.

Steve Silk is a contributing editor to Fine Gardening. His article "The Genesis of New Plants" appears in the January/February 2002 issue of Fine Gardening (#83).

Photos: Steve Silk

An Online Extra to Fine Gardening #83, pp. 60-65
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