AGRICULTURE: Transgenics Will Not Save the Banana, Say Experts

By Julio Godoy Reprint | | Print |

Julio Godoy - Tierramérica*

PARIS, Feb 7 2003 (IPS) - Neither pesticides nor genetic manipulation will save the Cavendish banana from disappearing, says scientist Jean Vincent Escalant, research coordinator for the International Network for Improvement of the Banana and Plantain (INIBAP), following the uproar caused by the recent announcement of this fruit’s imminent demise.

In mid-January, Emile Frison, INIBAP director, warned that the Cavendish, the banana variety most widely consumed in the industrialised world, could disappear within the decade due to the onslaught of the fusarium fungus, against which pesticides have proved useless.

The only option is to find a new resistant variety, Frison said in the article "Going Bananas", published by New Scientist magazine.

The story made it seem as though Frison, who is leading the efforts to decipher the fruit’s genome, is staking bets on genetic modification to save the banana.

"Beyond academic interest in biotechnology, Frison sees it as the only hope for the banana," concludes the article.

However, Escalant said in a conversation with Tierramérica, "New Scientist published a set of opinions apparently in favour of genetic manipulation, and led readers to believe that INIBAP was the source of that information. Which it wasn’t. We are convinced that the conventional crossbreeding methods are the most efficient in the long term."

When asked if alarm is merited in looking at the future of the Cavendish banana, Escalant, a PhD in plant physiology, university professor and author of numerous scientific publications, admitted, "We used a statement that was a bit exaggerated."

"But we did so because we wanted to call attention to a real problem that the banana growers have been facing for several years in Asia, Australia and Africa: the fusarium fungus," he explained.

This fungus causes "race 4" of Panama disease and attacks the Cavendish variety of banana.

"We fear that in the short term this disease will expand in Latin America and the Caribbean as well," said Escalant.

The public’s reaction to the article was immediate. "Most comments have been positive and come from researchers in banana- producing countries who say that the article was useful for convincing governments and other institutions to step up research efforts against the disease," he said.

But INIBAP also received criticisms. "Some reproached us for the false impression, given by the New Scientist, that we support genetic manipulation of the banana as the best solution against the disease," said the expert, pointing out that INIBAP was not the source of those opinions.

The institution stands by conventional crossbreeding techniques as the most efficient means of improving the banana and plantain crops in the long term, Escalant said.

He noted the similarities between the danger hovering over the Cavendish today and the extinction of the Gros Michel variety 50 years ago.

"In the 1950s, the Gros Michel was the most grown banana variety in the world. But then emerged the first strain of Panama disease, also a fungus, which forced nearly all growers around the world to replant hundreds of hectares of Gros Michel with the Cavendish, which was resistant to the disease."

"In less than 10 years, the Gros Michel disappeared. We want to prevent the same thing from happening to the Cavendish. The problem is much more serious today because we don’t have a banana variety with which to replace it," said Escalant.

The fusarium fungus lives in the soil and penetrates the plant through lesions in the roots or leaves. Once inside the plant it spreads through the vascular system. The result is blockages that keep the sap from circulating through the plant, ultimately killing the banana tree.

And there are no effective pesticides available against this fungus, but even if there were, chemicals are not the best option, the INIBAP expert commented.

"The intensive use of pesticides has negative secondary effects on the environment, in addition to the high financial costs, which make them prohibitive for small and medium growers," he said.

Nor is genetic manipulation of the banana plant a long-term solution, he added.

"With current knowledge of genetic modification, scientists would only be able to intervene in one or two genes of the banana. Any pathogenic agent, not only the fusarium fungus, would need very little time to overcome such a simple genetic blockade," said Escalant.

So what are the alternatives for fighting the fusarium? "Conventional biological crossbreeding methods, which our institute is promoting in Latin America and Africa," says the expert.

"The bananas we eat are a sexually sterile fruit. Biologists can artificially fertilise certain varieties of the banana, using large quantities of pollen. This is how we obtain a fertile female variety, which we cross with wild male banana plants, which are resistant to race 4 of Panama disease, but are not edible.

"From the cross of artificially fertilised female banana plants and wild male banana plants, we could obtain a variety that is both edible and immune to the disease," he explained.

However, if such research is to be productive, more financing is needed.

"The banana is the fourth leading plant-based food in the world, after rice, maize and wheat. But while nearly a thousand institutions around the world worry about increasing the food security of rice, there are only five specialising in the banana," Escalant points out.

These are the Honduran Agricultural Research Foundation (FHIA), the Brazilian Enterprise for Agricultural Research, and two institutions in Africa and one in the Caribbean.

Financial resources are lacking, too, he says, "because of a misunderstanding."

"The banana has had a bad image, as a product in the hands of a few multinationals that only want to export the fruit. But it is also a very important crop for hundreds of thousands of small and medium farmers," explaining that investing in banana research would be a smart social investment.

"Thanks to the campaigns INIBAP has led, donor countries are beginning to understand that financing research on the banana is a way to promote development."

* Tierramérica is a specialised news service (www.tierramerica.net) produced by IPS with the backing of the United Nations Development Programme and the United Nations Environment Programme.