It's been almost 20 years since the first genetically modified (GM) crop was approved for commercialization, and still the range of biotech foods available to the public is paltry. Soybeans, corn and cotton that tolerate high doses of herbicides and fend off pests--technologies that benefit rich-world farmers--are nearly all the choices we have.
But scientists have the tools to engineer crops that can benefit far needier populations. Here is a sampling of a few of those crops in development. The trick is finding a profitable way to get these crops out of the lab and past convoluted regulations.
About a half a cup per day--less than what a Vietnamese child might eat--of this "golden" rice can provide all the daily vitamin A a person needs. That's important for people whose primary food is rice, a poor source of essential nutrients. About half a million children go blind every year from vitamin A deficiency.
The technological breakthrough for golden rice came back in 1999, and the crop quickly became a symbol for those who believe in the lifesaving potential of GM crops. But political hurdles delayed field-testing by eight years. In 2008 the rice's developers, the Golden Rice Humanitarian Board, finally received clearance in the Philippines to conduct field trials. The group is fighting for regulatory clearance in six other southeast Asian countries.
After a lethal plant virus swept through this field trial in Tha Pra, Thailand, the GM papaya trees on the right stood hearty, while the conventional trees on the left fell sickly and fruitless. The virus, called ringspot, has decimated nearly all of Thailand's papaya, a staple food that many Thai people eat three times a day.
Thai researchers in 2004 were seeking regulatory approval for this biotech papaya when their government abruptly banned all GM crops and ordered every field trial destroyed. All that's left of this research site are a few seeds that Thai scientists stashed in a refrigerator.
At this research station in the Philippines, scientists at the International Rice Research Institute are developing GM rice that can tolerate drought, one of the toughest stresses on crops. In the tightly sealed structure, scientists adjust soil moisture and water tension as well as air temperature and humidity to mimic the conditions that rice would face during droughts.
Their goal is to engineer rice strains that can produce high yields despite those conditions. The institute is also working on rice that can tolerate salt water, which affects millions of acres of coastal rice paddies in places like Bangladesh.
From drought-resistant to flood-resistant: These varieties of rice can overcome floods by stretching their grassy stems to reach the air above the water. Like a snorkel, the elongated stem allows the plant to exchange gases with the atmosphere while most of it is submerged.
Japanese scientists in August reported that they had not only found the genes responsible for this trait (and named them SNORKEL1 and SNORKEL2), but had also successfully introduced those genes into other, more highly productive rice varieties. The hope is to engineer rice that combines these two key traits, helping Asian farmers prosper even during monsoon seasons.
Some of the best sources of antioxidants are expensive fruits such as blackberries and blueberries, but these purple tomatoes may provide a cheaper option. Using genes from a snapdragon flower, a group led by Cathie Martin at the John Innes Centre in the UK created a tomato with unprecedented levels of anthocyanins, a kind of antioxidant that has been linked to reduced incidence of cancers.
In fact, cancer-prone mice fed a diet of 10 percent powdered purple tomato lived significantly longer than mice fed regular tomatoes, the scientists reported. Martin and her colleagues are studying the tomatoes in greenhouse trials and are planning a health study on human volunteers.
This corn got a nutritious boost when scientists this year introduced seven genes that made it a viable source of four vitamins.
For people in sub-Saharan Africa, where white corn is a staple food, substituting this biotech variety could help them meet their daily recommended intake of vitamin A and folate. The corn also offers six times the normal amount of vitamin C and three times more vitamin E, compared with ordinary white corn. Researchers at Spain's University of Lleida are applying for permission from U.S. regulators to conduct a field trial.
Bananas are a staple food in countries like Uganda, where the average person eats more than two pounds of the fruit every day. But banana-based diets are deficient in iron and vitamin A, leaving many Ugandans malnourished. A research team led by James Dale at Queensland University of Technology in Australia is genetically modifying Cavendish bananas so that they provide enough iron and beta carotene to meet recommended daily intakes of those nutrients.
The team has been conducting field trials for over a year in Australia, and expects to test the technology on Ugandan soil this year, making the banana the first biotech crop to be field tested there.
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