COURTESY OF UNIVERSITY OF HAWAII COOPERATIVE EXTENSION SERVICE
The early effects of black Sigatoka disease are visible on this leaf. In Hawaii, the disease, caused by an airborne fungus, is also called black leaf streak. The disease doesn't kill banana stalks, but causes sharp cutbacks in fruit production.
HILO >> Recent news articles around the world have warned about the possible extinction of bananas within 10 years due to several diseases including "black Sigatoka." Crop disease hype
doesn’t faze isle growersA UH researcher says Hawaii
fungicide laws keep bananas safe
By Rod Thompson
CORRECTION
Wednesday, February 12, 2003» University of Hawaii researcher John Hu is conducting genetic engineering studies on banana bunchy top virus. A story on page A20 Sunday incorrectly identified the disease he is researching.
The Honolulu Star-Bulletin strives to make its news report fair and accurate. If you have a question or comment about news coverage, call Editor Frank Bridgewater at 529-4791 or email him at corrections@starbulletin.com.
rthompson@starbulletin.comBut in Hawaii, where black Sigatoka has been present for four decades and banana production has flourished despite it, the hubbub is viewed with aplomb.
Richard Ha, the state's largest banana grower with 600 acres, noted that the entire, three-decade growth of his company, Keaau Banana Plantation, Inc., has taken place in the presence of the disease.
"We live with it. We don't give it much thought," he said.
The brouhaha began when Belgian banana researcher Emile Frison talked about extinction in the Jan. 16 edition of the British publication New Scientist.
News agencies such as Reuters and the BBC quickly published stories about it that were translated and published around the world in languages ranging from Serbo-Croatian to Vanuatu (South Pacific) pidgin.
The interest was due not only to bananas being one of the world's favorite fruits, but also because cooked bananas are a staple like rice in many countries, especially in Africa.
Frison's theory is that most commercially grown bananas are the Cavendish variety, and like all edible varieties, they have lost the ability to reproduce sexually via seeds, a process that mixes genes and produces plant strength.
Bananas are now propagated by taking what in Hawaii are called "keikis" from the base of a mature plant and planting them elsewhere. Since the keikis are all clones, any disease that can kill one can kill all.
And one of those diseases is black Sigatoka, in Hawaii called black leaf streak, caused by an airborne fungus on banana leaves.
Huge commercial plantations in Latin America control the disease using fungicides. In those countries, the fungus is acquiring resistance to the chemicals, hence Frison's doomsday prediction.
But in Hilo, Scot Nelson, a University of Hawaii researcher of black Sigatoka, says the Latin Americans have problems because they massively overuse fungicides, reportedly as many as 40 applications from planes per year.
Hawaii growers abide by state law that restricts a key fungicide to no more than eight times per year.
And that's why grower Ha can speak with calmness.
Nelson has tested local samples of the fungus and found it is not becoming resistant to fungicides here, he said.
Also, about a quarter of bananas in Hawaii are apple bananas, which resist black Sigatoka fairly well.
"So I do not agree with the blanket statement that this disease will or can wipe out bananas worldwide," Nelson said.
But Latin American plantations could be in trouble.
"That in itself would be a significant blow to the average consumer in North America and Europe," Nelson said.
Nelson believes the answer to the problem is better growing techniques, including mixing of various crops on plantations instead of huge mono-crops.
Frison said the answer may be genetic engineering. Frison works for an international network of banana researchers that is studying banana genetics and is proposing genetic engineering.
Big Island banana grower Lynn Richardson noted that University of Hawaii researcher John Hu is doing genetic engineering research on a disease that many people think is more threatening than black Sigatoka, namely "Panama wilt, race 4," which is caused by a virus.
Ironically, said Richardson, the current problem with Latin America for Hawaii is not the danger of a collapse in their production, but that they are producing too much.
That keeps the price of Latin American bananas cheap, so Hawaii-grown bananas can't compete with them.
New Scientist
Keaau Banana Plantation
University of Hawaii
