GENET archive

[Index][Thread]

2-Plants: Can the banana be saved - without GE?



-------------------------------- GENET-news -------------------------------

TITLE:  Can This Fruit Be Saved?
SOURCE: Popular Science, USA, by Dan Koeppel
        http://www.popsci.com/popsci/science/article/0,20967,1076199-2,00.html
DATE:   Aug 2005

------------------- archive: http://www.genet-info.org/ -------------------


Can This Fruit Be Saved?

"A Banana," says Juan Fernando Aguilar, "is not just a banana." The
bearded botanist and I are traipsing through one of the world's most
unusual banana plantations, moving down row after row of towering plants
and ducking into the shade of broad leaves in an attempt to avoid the
Central American midday heat. In an area about the size of a U.S.
shopping mall, Aguilar, 46, is growing more than 300 banana varieties.
Most commercial growing facilities handle just a single banana type - the
one we Americans slice into our morning cereal.

The diversity of fruit in Aguilar's field is astonishing. Some of the
bananas are thick and over a foot long; others are slender and pinky-
size. Some are meant to be eaten raw and sweet and some function more
like potatoes, meant for boiling and baking or frying into snack chips.
But Aguilar's admonition is aimed squarely at our northern lunch boxes
and breakfast tables.

For nearly everyone in the U.S., Canada and Europe, a banana is a banana:
yellow and sweet, uniformly sized, firmly textured, always seedless. Our
banana, called the Cavendish, is one variety Aguilar doesn't grow here.
"And for you," says the chief banana breeder for the Honduran Foundation
for Agricultural Investigation (FHIA), "the Cavendish is the banana."

The Cavendish - as the slogan of Chiquita, the globe's largest banana
producer, declares - is "quite possibly the world's perfect food."
Bananas are nutritious and convenient; they're cheap and consistently
available. Americans eat more bananas than any other kind of fresh fruit,
averaging about 26.2 pounds of them per year, per person (apples are a
distant second, at 16.7 pounds). It also turns out that the 100 billion
Cavendish bananas consumed annually worldwide are perfect from a genetic
standpoint, every single one a duplicate of every other. It doesn't
matter if it comes from Honduras or Thailand, Jamaica or the Canary
Islands - each Cavendish is an identical twin to one first found in
Southeast Asia, brought to a Caribbean botanic garden in the early part
of the 20th century, and put into commercial production about 50 years ago.

That sameness is the banana's paradox. After 15,000 years of human
cultivation, the banana is too perfect, lacking the genetic diversity
that is key to species health. What can ail one banana can ail all. A
fungus or bacterial disease that infects one plantation could march
around the globe and destroy millions of bunches, leaving supermarket
shelves empty.

A wild scenario? Not when you consider that there's already been one
banana apocalypse. Until the early 1960s, American cereal bowls and ice
cream dishes were filled with the Gros Michel, a banana that was larger
and, by all accounts, tastier than the fruit we now eat. Like the
Cavendish, the Gros Michel, or "Big Mike," accounted for nearly all the
sales of sweet bananas in the Americas and Europe. But starting in the
early part of the last century, a fungus called Panama disease began
infecting the Big Mike harvest. The malady, which attacks the leaves, is
in the same category as Dutch Elm disease. It appeared first in Suriname,
then plowed through the Car- ibbean, finally reaching Honduras in the
1920s. (The country was then the world's largest banana producer; today
it ranks third, behind Ecuador and Costa Rica.)

Growers adopted a frenzied strategy of shifting crops to unused land,
maintaining the supply of bananas to the public but at great financial
and environmental expense - the tactic destroyed millions of acres of
rainforest. By 1960, the major importers were nearly bankrupt, and the
future of the fruit was in jeopardy. (Some of the shortages during that
time entered the fabric of popular culture; the 1923 musical hit "Yes! We
Have No Bananas" is said to have been written after songwriters Frank
Silver and Irving Cohn were denied in an attempt to purchase their
favorite fruit by a syntactically colorful, out-of-stock neighborhood
grocer.) U.S. banana executives were hesitant to recognize the crisis
facing the Gros Michel, according to John Soluri, a history professor at
Carnegie Mellon University and author of Banana Cultures, an upcoming
book on the fruit. "Many of them waited until the last minute."

Once a little-known species, the Cavendish was eventually accepted as Big
Mike's replacement after billions of dollars in infrastructure changes
were made to accommodate different growing and ripening needs. Its
advantage was its resistance to Panama disease. But in 1992, a new strain
of the fungus - one that can affect the Cavendish - was discovered in
Asia. Since then, Panama disease Race 4 has wiped out plantations in
Indonesia, Malaysia, Australia and Taiwan, and it is now spreading
through much of Southeast Asia. It has yet to hit Africa or Latin
America, but most experts agree that it is coming. "Given today's modes
of travel, there's almost no doubt that it will hit the major Cavendish
crops," says Randy Ploetz, the University of Florida plant pathologist
who identified the first Sumatran samples of the fungus.

A global effort is now under way to save the fruit - an effort defined by
two opposing visions of how best to address the looming crisis. On one
side are traditional banana growers, like Aguilar, who raise experimental
breeds in the fields, trying to create a replacement plant that looks and
tastes so similar to the Cavendish that consumers won't notice the
difference. On the other side are bioengineers like Rony Swennen, who,
armed with a largely decoded banana genome, are manipulating the plant's
chromosomes, sometimes crossing them with DNA from other species, with
the goal of inventing a tougher Cavendish that will resist Panama disease
and other ailments.

Banana experts disagree on when the Latin American and African crops will
be hit by the Panama fungus. Ploetz won't venture a guess, but he notes
that the Malaysian plantations went from full-scale commercial operations
to "total wipeout" in less than five years. Currently, there is no way to
effectively combat Panama disease and no Cavendish replacement in sight.
And so traditional scientists and geneticists are in a race - against one
another, for certain, but mostly against time.Honduras is in many ways
the epicenter of the American super- market banana. More than a century
ago, a pair of U.S. companies - United Fruit and Standard Fruit, now
known, respectively, as Chiquita and Dole - built some of the world's
first commercial banana plantations in the Central American nation.
Technological infrastructure was the first task: The banana producers
began as railroad companies, with friendly local governments granting
thousands of acres of surrounding rainforest for each mile of track laid.
Although bananas had been sporadically available in the U.S. since
colonial days, the post-Civil War advent of motorized transit by rail and
steamship made the importation of tropical fruit practical. (An 1896
article in this magazine entitled "Where Bananas Grow" observed that the
U.S. market for bananas had increased more than 40-fold in the previous
quarter century, owing mostly to improved "facilities for transporting
and preserving them.")

By the early 1900s, bananas surpassed apples as the nation's favorite
fruit, becoming so popular that in the days before municipal trash
collection, the slapstick slip on a discarded peel was a genuine hazard.
(Luckily, Boy Scouts were on the case: "A good turn may consist in
removing a piece of banana peel from the pavement," their 1914 handbook
advised.) The problem of banana litter helped lead to the development of
the earliest urban refuse-removal networks, according to Virginia Scott
Jenkins, author of Bananas: An American History.

Bananas have always been a technology incubator. Because they're a time-
sensitive product - they need to be harvested green, then delivered to
market just at ripening time - systems had to be developed to bring
precision to the picking and shipping processes. Leonel Castillo, a
banana-production consultant who grew up in Chiquita's corporate compound
near the city of San Pedro Sula, on Honduras's northern coast, explains
that the old way was "to wait until you could see the ship coming over
the horizon toward port." Then banana workers would engage in frantic
nonstop harvesting and rush the crop to the boats. Chiquita engineers
developed the first radio networks in the tropics as a way to bypass this
antiquated system. The fruit's popularity also led to the development of
ripening rooms whose controlled environment can slow or speed the way
picked fruit ages; refrigerated steamships; and early precursors to bar-
coding that allowed each bunch to be tracked by field, plantation,
originating country and shipping container.

But the main thrust of banana tech has always been the search for new
varieties. FHIA now occupies the buildings at Chiquita's old Honduran
headquarters that since the 1920s have been the global hub for
traditional banana breeding (the buildings also hint at the lifestyle
once provided for executives at tropical outposts, spreading across a
campus-like compound that once housed a swimming pool and horse-racing track).

Chiquita abandoned most tropical research in the 1970s; FHIA opened in
1986 as part of an initiative to promote local economic development. One
of the first new breeds to come out of the effort, which is funded by a
combination of government and private grants, was the "Goldfinger"
banana, also known as FHIA-01. The Goldfinger was developed by
painstakingly cross-breeding samples from the more than 350 banana types
originally collected by United Fruit scientists. It is a highly versatile
fruit, suitable for cooking and eating; it has a slightly tart, apple-
like flavor and is one of the few bred bananas to gain significant
consumer acceptance.

The Goldfinger was created by Philip Rowe, a legendary advocate for trad-
itional methods of banana breeding; Rowe died in 2002, and the program
was taken over by Aguilar. Like Rowe, Aguilar believes that conventional
hybridization - not genetic engineering - is the best way to devise a
Cavendish replacement. The Goldfinger was evidence of that belief: It
transported well and caught on in certain markets, notably Australia. But
it didn't taste like the sweeter Caven- dish and never took hold in the
Americas.Aguilar moves quickly through the fields surrounding the old
Chiquita headquarters, chain-smoking Marlboros between taking bites of
sample fruit. He understands that to actually find the needle he's
looking for in his vast yellow haystack, he's got to maintain a fast
pace. But he also knows that agricultural husbandry is a slow process. It
requires patience. To balance both, he says, it is necessary to see the
job as something more than just ordinary science. The race to save the
banana is personal. "The bananas," he says, "are my children."

Each of Aguilar's experimental varieties are tagged and set off in rows.
To put the new bananas to the test, no fungicides are used here, so it
isn't difficult to see the difference between healthy, resistant plants
and afflicted ones. The strong plants have expansive green leaves. Both
Panama disease and another malady, Black Sigatoka (which unlike Panama
disease is present in Central America), cause leaves to wilt and crumble,
leaving the fruit unprotected from the sun and reducing photosynthesis -
the dying plant can't make sugar, and fruit yield is severely diminished.
Sigatoka is a major problem, but, unlike Panama disease, it is
controllable with chemical sprayings.

Bananas grow from an underground root structure; what juts out of the
ground is more like a stem than a trunk. A long spike, covered in tiny
flowers, emerges from the stem. The female flowers grow into fruit at the
base of the flower-bearing stalk, while the male flower - bulbous and red
- grows at the very tip of the stalk, weighing it down, curving toward
the ground. The fruits grow in spiraling groups called "hands" (they're
the bundles you buy in the store; an individual banana is called a
"finger"). A banana plant can have up to a dozen attached hands;
together, a plant's entire output is called a "bunch."

Bananas are different from most other cultivated plants in that almost
all the varieties - including the Cavendish - lack seeds (that round,
dark center in a banana slice is the vestige of what was once the fruit's
reproductive core). Cultivated bananas never reproduce sexually on their
own. Rather, new stems grow from the existing root, sometimes for many
years. Forcing the pollen from one male flower to make its way to the
female of another plant, however, is how traditional banana breeders like
Aguilar's team develop new varieties. Most mornings, usually just as dawn
is breaking, a team of hand pollinators pedal through FHIA's dirt-tracked
fields on battered three-speed bicycles. They move from plant to plant,
gathering the powdery pollen from the males and transferring it to
receptive female flowers, keeping meticulous records of their activities
(Aguilar calls the field "a giant spreadsheet"). The goal of all this is
to get seeds, and to use them to grow Aguilar's experimental varieties,
one of which, he hopes, will ultimately yield a tasty, market-friendly
Cavendish replacement. What are the odds of an individual seed ultimately
yielding a thriving hybrid? "About 1 in 10,000," Aguilar says.

It takes about four months for a pollinated plant to bear fruit, which is
harvested and brought to a processing shed for seed extraction. Workers
press thousands of bananas through mesh strainers. About one seed is
found for every 300 bananas. The seeds are then brought indoors, to what
Aguilar calls the "embryo rescue unit." Of the tiny number of seeds, only
a third of them actually germinate. As the plants grow, they move from
test tubes through a series of protected greenhouses and finally back to
the fields. The first fruits are harvested two years after the initial
pollination. "That's when we begin to get a sense of what we got,"
Aguilar says.The difference between a near-natural banana and an FHIA
hybrid can be significant. Aguilar shows me a series of photos dating
back to 1959. The fruit yielded by Phil Rowe's earliest experiments in
cross-breeding are very small. The descendants of those initial plants -
the most recent is called FHIA-26 - are massive and hardy.

Looking good is important for a consumer-friendly banana (Chiquita used
to publish color charts that were hung in supermarkets, all designed to
guide shoppers to the most yellow bananas). But taste is equally
critical. As Aguilar leads me through the fields, we pass row after well-
delineated row of exotic bananas. He stops at a group of plants marked
"Umpiko," pulls a fruit off the stem, and peels it, taking a quick taste
before handing a chunk to me. It's quite good - maybe milder-tasting than
typical bananas - but the big problem with the Umpiko is that it ripens
too fast. It would never make it to U.S. stores in time. A few rows down,
we duck into the shade of a low-slung plant. Height, too, is key; the
Gros Michel was so tall that it was susceptible to wind blow-down. The
Cavendish is considerably lower and, therefore, hardier in bad weather,
although in 1998 nearly the entire Honduran banana crop was still wiped
out by Hurricane Mitch. Aguilar picks and tastes another banana.

None of our snacks are Cavendish, or descended from Cavendish - and none
taste much like the banana I'm used to. Just as importers were afraid
that consumers would reject today's most popular banana when it replaced
the Big Mike, they worry that a fruit that isn't creamy and sweet, like
the Cavendish, will destroy markets. "We can make bananas that could be
equal," Aguilar says, "but not the same."Far from the steamy bananalands
of the Caribbean, an entirely different effort to create the banana of
the future nearly fills a basketball-court-size greenhouse 20 minutes
east of Brussels, Belgium. Rony Swennen is director of the Laboratory of
Tropical Crop Improvement at the Catholic University of Leuven. He
oversees the world's largest collection of bananas and plantains. More
than 1,200 varieties are kept in rows of test tubes, tiny plantlets
encased in glass - each a potential donor of genetic material to be used
in engineering new banana varieties. For the past decade, Swennen and his
colleagues have been decoding and manipulating banana genes in the hopes
of building resistance to the main afflictions that strike the fruit's
commercial varieties: Black Sigatoka; nematodes, a kind of minuscule
worm; and the various strains of Panama disease.

Banana-bereft suburban breakfast tables notwithstanding, Swennen says
that the real danger the spread of these path- ogens poses is in the
developing world, especially East Africa. In the densely populated
countries around Lake Victoria - Uganda, Kenya, Tanzania, Burundi and
Rwanda - bananas are primary nutrition, accounting for near-total
carbohydrate consumption in some diets (in Uganda, the word for food,
"matooke," translates from Swahili as "banana"). The bananas eaten in
East Africa are not the dessert-style fruit consumed in the West; they
are far more versatile (there's even a beer brewed from bananas sold in
Kampala). But like the Cavendish, African bananas are threatened. The
Ugandan National Banana Research Program says that plants that once
yielded fruit over a 50-year life span are now so much less resistant to
disease that they become unproductive and require replacement after as
few as five years. Bananas are also essential to the region's other
crops: They provide cover for tropical forests, allowing staples such as
beans and sweet potatoes to grow in their shade. Without bananas, Swennen
says, 20 million people would face "massive destabilization."

The reason bananas are so susceptible to disease has to do with their
ancient origins. Almost no plant has been cultivated longer by humans.
The earliest banana production began in Southeast Asia, but of the
hundreds of varieties found in that region, only about 10 or 15,
according to Swennen, were brought to Africa. (Bananas are a perfect crop
for subsistence farming, since once a family has a healthy plant, no more
seeds need to be planted - or bought; instead farmers simply replant
shoots, called "suckers," from existing trees.) Bananas mutate easily,
and of the few Asian banana varieties that originally made it to Africa,
more than 200 new varieties have emerged. But these varieties remain
genetically similar, so they're prone to parallel afflictions. The
situation in Latin America is even worse. "Only a few moved from Africa
to there," Swennen says, "so you've got even lower variability."

The geneticist has already created one sweet banana that, using genetic
material from radishes, has built-in resistance to Black Sigatoka. The
lab is also developing high-yield plantains for Africa and a banana
manipulated to be high in beta-carotene. Swennen emphasizes that biotech
is literally the only way to save the Cavendish, which, because it is 100
percent seedless, can't be improved on by traditional hybridization
methods. And FHIA's approach of growing a new variety from scratch, he
argues, is too slow.

Traditional banana scientists, like the ones in Honduras, know that the
methods they use are slower by decades than the lab-induced DNA
manipulation that Swennen and his fellow researchers are working on. But
they also know that resistance to genetically engineered foods runs deep
among the world's consuming public. A recent survey by Fyffes (the banana
importer that is to Britain what Chiquita is to the U.S.) found that 82
percent of U.K. shoppers said they would never buy a genetically altered
banana, even if proven to be safe, even if doing so allowed the
elimination of pesticides and other potentially harmful agricultural
chemicals - a major advantage, supporters say, of biotech crops. Public
aversion to DNA-altered foods exists throughout Europe, where most such
fruits and vegetables are banned. Although Chiquita wouldn't comment for
this story, company executives have repeatedly rejected biotech
techniques for use in consumer products.

"I can't understand this romantic idea that nature is perfect, and that
what we do is create Frankensteins," Swennen says. People "are frightened
- and they're wrong." He believes that the threats bananas face mean that
they are likely to be the bioengineered food that finally forces global
shoppers to consider - and accept - science's inevitable intervention in
the agricultural process. "There's almost no choice," he says. "We need
resistant bananas."The sprawling old compound in Honduras still houses a
small set of Chiquita offices, but the company's presence in the region
is better symbolized by the oversize, fading logo - a blown-up version of
the sticker you find on your grocery-store fruit - painted on the side of
the com-pany's now run-down country club. Chiquita and Dole still farm
thousands of acres here, but they're more absentee landlords than the
all-powerful entities they once were. When I had dinner at the club,
Leonel Castillo told me that the dining room we were sitting in was "the
place where governments were once made - and broken." That controversial
legacy, which led to the coining of the term "banana republic," is one of
the reasons the major banana companies are generally unforthcoming with
the media. Chiquita does nod to the old days on its Web site, where a
chronology page called "Our Complex History" acknowledges, alongside more
positive achievements, dubious acts: the company's participation in the
1954 overthrow of Guate- malan president Jacobo Arbenz Guzmán; the 1961
use of its corporate steamship fleet to support the failed Cuban Bay of
Pigs invasion; antitrust lawsuits; the suicide of United Fruit chairman
Eli Black (he jumped from the 42nd story of New York's Pan Am building)
after a 1975 bribery scandal. Banana companies remain the focus of
environmental and labor activism, although both Chiquita and Dole have
worked in recent years to have their operations certified by groups such
as the Rainforest Alliance.

There's no doubt that workers at banana plantations are better treated
than they were in the 1950s, when Honduran author Ramón Amaya Amador
published an allegorical novel called Green Prison, but some critics say
the industry has a long way to go. The biggest problem, says Alistair
Smith, coordinator of BananaLink, a British activist organization, is the
continued use of pesticides, which have huge "negative human and
environmental impact." His group cites instance after instance of long-
term ill health effects in workers.

The pesticide issue is a big one for banana researchers as well. It isn't
so much for banana consumers, at least directly, since most of the
substances used on the plants don't make it into the flesh of the thick-
skinned fruit. But the human and monetary cost of spraying grows higher
as more chemicals are needed to battle increasingly virulent diseases.
"In the 1970s we controlled Black Sigatoka by spraying 10 to 12 times a
year," says FHIA director Adolfo Martínez, an agricultural economist.
That frequency has jumped to almost weekly, at a cost of up to $1,000 per
acre for every spraying. "There will come a point at which that is
neither environmentally nor economically sustainable," Martínez says.
Despite concerns over pesticides, the position of the fruit companies has
been to combat disease with chemicals. David McLaughlin, Chiquita's
senior director for environmental affairs, told the Boston Globe in 2003
that programs like FHIA's "cost us a lot of money for very little result.
We concentrate on research into fungicides now."

The increasing possibility of problems with the Cavendish has led to a
change in that position. During a 2004 conference call with shareholders,
Chiquita president Fernando Aguirre said that FHIA would be "providing
Chiquita with an R&D department that is working on several varieties of
bananas with different sizes and tastes. They are also working on better
resistance to plant diseases."

How much time is left for the Cavendish? Some scientists say five years;
some say 10. Others hold out hope that it will be much longer. Aguilar
has his own particular worst-case scenario, his own nightmare. "What
happens," he says, with a very intent look, "is that Pan-ama disease
comes before we have a good replacement. What happens then," he says,
nearly shuddering in the shade of a towering banana plant, "is that
people change. To apples."


--


GENET
European NGO Network on Genetic Engineering

Hartmut MEYER (Mr)
In den Steinäckern 13
D - 38116 Braunschweig
Germany

P: +49-531-5168746
F: +49-531-5168747
M: +49-162-1054755
E: coordination(*)genet-info.org
W: <http://www.genet-info.org>



-----------------------------
   GENET-news mailing list
-----------------------------