|Advertising|Jobs 転職|Shukan ST|JT Weekly|Book Club|JT Women|Study in Japan|Times Coupon|Subscribe 新聞購読申込|
|Home > Life in Japan > Environment|
Thursday, Aug. 2, 2001
You say Frankenfruit, we say miracle tomato
By ROWAN HOOPER
Prince Charles played into the hands of the sensation-seeking media -- and drew the groans of scientists -- with his comments last year on genetically modified crops. They are, he said, "Frankenstein foods." Rather than genetic manipulation, he urged investment in "traditional systems of agriculture."
So instead of any reasoned treatment of the issues, we got a media feeding frenzy tacitly endorsed by a public figure who might have better directed his words about plants to his plants. If His Royal Highness' objections to GM foods are due to misgivings about genetic manipulation of their genome, which from the Frankenstein comment they seem to be, then he confuses the issue right from the start.
All farming is "unnatural" in this sense. All plants grown commercially are freaks of nature -- peas are 10 times the volume of their ancestors in the wild; cobs of corn are 30 times longer than those produced by natural selection. The changes were brought about slowly, by artificial selection acting to exaggerate existing traits. With transgenic plants, big, new changes are brought about very quickly -- and here's where people get worried, and newspaper writers get some juicy, scary copy.
It's definitely time for some good news for genetically engineered plants. Their nutritional and ecological potential is massive -- and is desperately needed. The world's population is still climbing and will peak in 2070, according to Wolfgang Lutz of the International Institute for Applied Systems Analysis in Laxenburg, Austria. Nature today published Lutz's findings that the world population will level out at 8.4 billion and then decline. The proportion of people over 60 will leap from the current 10 percent to 34 percent, and nations in the Southern Hemisphere will be increasingly dominant.
With an unprecedented number of mouths to feed, farmers will need all the help they can get. Help comes now from a U.S.-Canadian team of researchers into GM crops, who seem to have cracked one of agriculture's greatest problems -- how to grow plants in saltwater. The paper is published in the August issue of the journal Nature Biotechnology.
More than a quarter of the world's irrigated land is so salty that little can grow; what can grow is stunted. The loss of this farmable land is directly at odds with the increasing world population. Developed countries will require an estimated 20 percent more food over the next 30 years; developing countries will need 60 percent more. A return to "traditional systems" of agriculture, while made with good intentions at heart, is clearly unreasonable. No doubt the future king won't go without his dinner, but what about the rest of us? Not to mention the millions in developing countries.
The researchers, Hong-Xia Zhang of the University of Toronto and Eduardo Blumwald of the University of California, Davis, made a tomato plant that can grow in saltwater but produces normal, edible fruit. Sodium affects so many cellular processes that it was believed it would require highly complex engineering of many genes to produce a plant that could tolerate saltwater. Researchers, however, managed it by changing just a single gene.
They took a DNA sequence containing a gene that regulates the movement of sodium ions in thale cress, a relative of the cabbage that is often used in plant research, and introduced it into normal tomato plants. The gene produces high levels of a "transport protein" that moves sodium into isolated chambers in the leaves. The plants, effectively, were installed with a salt pump. With the salt stashed safely away in the leaves, the plants could grow normally. Fruit quality was unchanged. Modified plants were able to grow in water about a third as salty as seawater. At those concentrations, nontransgenic tomato plants either died or were severely stunted.
Blumwald hopes that a commercial breed of salt-tolerant tomato plant will be available in three years, and that other crops can also be genetically modified to grow in salt-damaged soil or soil irrigated with salty water.
"Since environmental stress due to salinity is one of the most serious factors limiting the productivity of crops, this innovation will have significant implications for agriculture worldwide," he said.
Crop irrigation gradually increases soil salinity as sodium and other salts picked up as water drains through rocks are deposited in the soil. With Zhang and Blumwald's breakthrough we have the chance to maintain a traditional method of agriculture, as Prince Charles wants, by using so-called "Frankenstein" genetics to solve its inherent problems.
E-mail Rowan Hooper at firstname.lastname@example.org