Greening the Worlds Most Popular Fruit - Bananas
Greening the World’s Most Popular Fruit
THE BANANA has a huge fan base. Babies and the elderly love its easy-to-eat-and-digest sweetness, athletes gulp it for potassium-rich quick energy, and comedians have worked its shape and packaging into endless gags. The banana is popular worldwide, with more than 25 pounds consumed annually per capita in the United States, most eaten straight out of the wrapper. In East Africa, where bananas and their plantain cousins are dietary staples, consumption is seven times that amount.
What the banana lacks, though, is a huge genetic base. The familiar yellow fruit—botanically, a berry—is largely derived from a single variety known as Cavendish grown on plants that are essentially cuttings, or clones, of the same stock. The birds and the bees have nothing to do with cultivated bananas, and this lack of sexual reproduction, with its mixing of genes, leaves the crop vulnerable to diseases and pests such as fungi, viruses, bacteria, insects and roundworms, some of which have become epidemic in recent years.
This means that conventional banana production depends heavily on pesticides—and lots of them. Fungicides, for example, may be applied 40 times a year, even though the chemicals lose their effectiveness with overuse. Worse, these highly toxic compounds often drift or run off of farm fields, posing a threat to fish, birds and other species—including humans. Even more poisonous to people and the environment are the nematicides typically used to control roundworm pests. And conventional banana production generates a host of other problems as well—from rivers polluted with eroded sediment and plastic waste to tropical forests razed to carve out new plantations.
These environmental problems, along with historically poor conditions for banana workers, have prompted several organizations to create certification and seals of approval for producers that meet certain environmental and social standards. In addition, a small but growing number of exporters are harvesting organically grown bananas, eschewing agrochemicals altogether. The result: Consumers today have a much greater opportunity to purchase bananas that are friendly to the environment than even a decade ago.
The Better Banana Project, sponsored by the New York-based Rainforest Alliance, is one of the oldest certification efforts. Launched in 1991, it requires producers to maintain health and safety standards for workers and to demonstrate reduced pesticide use and other sound environmental practices such as soil conservation and proper waste disposal. Today 15 percent of all bananas traded on the global market are certified by the project.
One major global producer, Chiquita Brands International, has converted all of its Latin American farms to meet the project’s standards. According to David McLaughlin, the company’s senior environmental director, about two-thirds of the Chiquita bananas sold in North America come from these certified farms.
The Better Banana Project has “improved conditions on all Chiquita plantations greatly,” says Robert Mack, an organic agriculture consultant to small-scale farmers in Costa Rica. The use of toxic nematicides, for example, has been halved on certified farms, and tons of blue plastic bags and twine, which once littered virtually all banana farms, have been recycled through the program. In addition, pay and other benefits for workers have improved greatly. Thanks to efforts of project participants, “the banana industry is making a long, slow 180-degree turn,” says the Rainforest Alliance’s Chris Wille, one of the project’s founders. “Now there’s even competition among workers to get jobs on certified farms and competition between farms to see who can have the cleanest and greenest one.”
Besides Chiquita, the Favorita Fruit Company, an Ecuadorian producer that supplies some European markets, has also achieved 100 percent certification of its farms. Eco-certified bananas are even grown in the United States: The Mauna Kea Banana Company in Hawaii markets these creamy, mildly tart apple bananas by mail order.
For pesticide-free fruit, one can choose organic bananas. Though less than one percent of the bananas sold in the United States now are organic, that fraction is growing by more than 20 percent per year nationally and by 30 percent globally, according to the United Nations Food and Agriculture Organization.
Certified organic bananas are taking root throughout Latin America, often in drier habitats where harmful fungi don’t occur. The Dominican Republic is the region’s biggest exporter of organic bananas, followed by Mexico and Colombia. Small- and medium-scale growers are even managing to grow organic bananas in Costa Rica, where the fungal disease black sigatoka is a constant problem for large producers. By planting bananas in the shade in combination with other marketable crops such as cacao, these producers can get a modest but pesticide-free crop that commands a premium price. U.S. consumers looking for organic bananas can often find them in natural food stores and even main grocery chains for just slightly more than conventionally grown bananas.
The fruit that sustains hundreds of millions of people is itself slowly becoming a more sustainable crop.
Science writer Christine Mlot buys her bananas in Madison, Wisconsin. For more information on the Better Banana Project, see www.rainforest-alliance.org.
Building a Better Banana
Scientists working to improve the pest- and disease-plagued banana turn first to the crop’s wild relatives in Southeast Asia. Though a couple of them have gone extinct, several hundred wild or cultivated Musa species and varieties still exist. Fruits of the wild plants are the converse of cultivated types: Instead of tiny brown flecks of remnant seed embedded in rich pulp, wild bananas have big stony seeds and little pulp. The seeds still work in wild bananas, which are pollinated by bats, creating a valuable reservoir of gene combinations that breeders in Belgium, Africa, and elsewhere have sampled and stored.
Some wild bananas are naturally resistant to the diseases of commercial crops, including a virulent new race of Panama disease caused by a fungus that is killing plants in South Africa, Australia and parts of Asia. Scientists also have found plants with natural resistance to black Sigatoka, another yield-diminishing fungal disease, considered the biggest threat to Latin America’s banana production. The challenge is getting these wild genes for resistance into the cultivated banana, which has an extra set of chromosomes to complicate the task. Researchers have resorted to tissue culture and other lab tricks to generate improved plants. Another hurdle is getting the improved plants to perform well in the field, work being conducted by the International Network for the Improvement of Banana and Plantain as well as other institutions.
Faster improvements may be on the way through an ongoing international project—the Global Musa Genomics Consortium—to sequence the genome of two banana varieties. Having the crop’s gene sequence would help scientists who are attempting either to breed or genetically engineer bananas with resistance to various diseases. Researchers in Hawaii, for example, have been working for the last decade to engineer the plant to resist bunchy top, a serious viral disease spread by aphids. In England, other scientists have modified a cooking banana with a rice gene to withstand nematode pests. Launched in 2001, the sequencing project is expected to be finished within the next five years.-Christine Mlot