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A similar transformation is taking place in the Peten rain-forest region of Guatemala. Villagers there are finding that if they plant velvet beans in the corn fields that they carve out of the forest, they can avoid buying high-priced fertilizers and bolster the fragile soil, since the beans replace the fields' lost nitrogen. The benefits include higher corn yields, lower expenses and, best of all, eliminating the need to hack down more rain forest when the soil becomes depleted. The idea to plant the beans, which originally came from an educational project sponsored by the nonprofit Rodale Institute in Pennsylvania, is spreading through Guatemala and other Central American countries. "What works for individual farmers will work for farms worldwide," says Anthony Rodale, vice chairman of the institute, which has championed sustainable agriculture for a half-century. The world's big cash crops are not always the ones best suited to subsistence farming in developing countries. Staples such as corn and potatoes provide carbohydrates and calories but are relatively low in vitamins and minerals. Moreover, many more obscure food plants are better able to thrive in arid or tropical areas. That's why Noel Vietmeyer has spent more than a quarter-century identifying valuable "forgotten" crops as a plant scientist for the U.S. National Research Council. The agency's 1996 book Lost Crops of Africa profiles 10 little used grain species out of sub-Saharan Africa's 2,000-plus food plants, from teff, an Ethiopian staple rich in protein and iron, to fonio, a cereal that grows well in sandy soil. Says Vietmeyer: "Africa, the continent that supposedly can't feed itself, has a cornucopia of answers lying there unloved, unstudied, unrecognized." SUPERPLANTS FROM THE LAB While Vietmeyer and his colleagues identify underutilized crops, other scientists create new ones through the magic of biotechnology. In the past, researchers have improved crops by crossbreeding different genetic strains of the same plant. Now it's possible to introduce dna from an entirely separate species of plant--or even from a bacterium or virus. How could that be useful? Consider one of the neat tricks pulled off by Monsanto, a biotech company headquartered in St. Louis, Missouri. Monsanto researchers injected dna from a soil bacterium into cotton plants. That dna caused the cotton plant's cells to make a protein deadly to several insects that plague cotton growers, including budworms and bollworms. When these pests invade fields containing the genetically altered cotton, they unwittingly ingest the venomous protein and develop a fatal digestive disorder. Using similar stratagems Monsanto has created a corn variety that is poison to the European corn borer and a potato that becomes the last meal for Colorado potato beetles. Sometimes bioengineering can help crops that are good food sources for indigenous peoples but have not reached their potential. Sweet potatoes are suited to Africa, given their ability to thrive in arid soil, but they are susceptible to a devastating viral plant disease. Working with Kenyan agronomist Florence Wambugu, Monsanto altered the sweet potato by injecting into its cells pieces of the virus. This "genetic vaccination" let the plant develop its own protection. Other companies around the globe are matching Monsanto's success. Britain's Zeneca, for example, says it is just five years away from marketing strains of wheat, rice, fruit and vegetables that are resistant to infestations by fungus. "Current technologies are like a Model T Ford compared to what we are coming up with," claims Zeneca group manager Nigel Poole. In the works at the world's biotech labs are drought-resistant corn and salt-tolerant wheat. Such breakthroughs are not coming a moment too soon. Although human birth rates have slowed, the proliferation of people on the planet still has enormous momentum. The world population is not expected to level off until after it passes 10 billion around the middle of the 21st century. While farmers have done a remarkable job of keeping food on the dinner table so far, it will not be easy for them to feed nearly twice as many mouths as they do today. But aided by the wisdom of sustainable agriculture and the wonders of biotechnology, they will have a fighting chance to give us our daily bread. --With reporting by Joanna Downer/Washington, Martin Penner/Rome, Mark Turner/Brussels and other bureaus |