We have probably always known better. Kenyans, along with other people in East and Central Africa, are the world's leading consumers of bananas.
Some scientists now call bananas the world's healthiest food because of their long list of proven health benefits – from improving digestion, making students smarter (because of high potassium) and even preventing certain cancers.
The peels can also help remove warts and shine shoes. But now, bananas are in the headlines not due to their health benefits but because a scary disease is threatening their existence.
The Panama wilt disease, also known as Fusarium wilt, is so dangerous that it is being called the HIV of bananas.
The current outbreak is caused by a virulent strain – called Tropical Race 4 (TR4) – of Panama disease, which is rapidly devastating banana production in Taiwan, southeast Asia, China, and parts of Australia.
There were also reported outbreaks in Mozambique, Jordan, Lebanon, and Pakistan, according to the Food and Agriculture Organisation (FAO).
Is this the beginning of the end of the banana?
"Bananas affected by Panama wilt show yellowing of leaves starting with the oldest. Some of the leaves droop, turn brown, dry and tear," says Dr Lusike Wasilwa, the director of crop systems at the Kenya Agricultural and Livestock Research Organisation (Kalro) in Nairobi.
The fungus that causes the disease resides in the soil. It first infects the roots and goes on to colonise the plant through the vascular system and can even reach the leaves. It blocks the flow of water and nutrients and eventually kills the plant.
Dr Lusike notes that the disease cannot be controlled with fungicides. It produces infectious spores that survive in the soil for decades.
As soon as another banana plant is grown nearby, these spores attack the plant and kill it. That means once the soil has been contaminated it becomes unfit for future bananas unless resistant varieties are grown.
This is what is causing a lot of anxiety, even in Kenya. In 1950, a deadly strain of Panama disease (called Race 1) destroyed Gros Michel banana, the world's most consumed variety at the time.
This banana was replaced by the Cavendish variety, which was resistant to that strain. Cavendish is currently the world's biggest export banana and is most susceptible to the current strain of Panama disease.
It is only grown in a few parts of Kenya.
Dr Lusike says luckily, the new strain (TR4) of panama disease that is obliterating bananas elsewhere, has not been observed in Kenya.
The only strains confirmed in Kenya are the old Races 1 and Race 2, which are largely manageable. The Race 1 is endemic in Kenya as it is in most parts of the world.
It is still a threat to the traditional varieties grown in the country.
Race 1 was observed in Kenya for the first time in 1952 in Malindi and Murang'a on a cultivar suspected to be Bluggoe, locally known as Bokoboko.
But it was not until mid-1990s that farmers and agricultural extension officers from other regions complained of severe outbreaks of the disease.
This strain also devastated the production of the sweet dessert bananas (apple bananas) in Kenya.
Dr Lusike says although the more virulent TR4 strain has not reached Kenya, farmers must take early precaution.
Kalro has been holding seminars to sensitise farmers on how to prevent spread of diseases in bananas.
Dr Lusike says the planting material (suckers, rhizomes) remain the most important methods of long distance dispersals.
"Movement of diseased banana trash and contaminated soil by man and machine are also significant. Surface irrigation and floodwater have also been shown to spread the pathogen. Other factors promoting dissemination include poor crop management and unreliable source of planting materials. Most farmers tend to use conventional banana suckers instead of tissue cultured planting material that are preferred," she says.
A 2008 report by Kalro researcher Dr Margaret Onyango (deceased in 2015) recommends plant quarantine such as stopping the movement of planting materials from affected regions.
It also recommends cultural control, that is, have fields clean of leaves and other plant debris; practise crop rotation and disinfect all farm equipment between banana stools.
Kalro says the Cavendish variety in Kenya is still being affected by the race one and 2 strains of the panama disease.
"Incidences of Fusarium wilt occur at a higher frequency in the Central region of Kenya, for instance, Murang'a, Nyeri and Kiambu particularly on the Cavendish genotypes," says Dr Ruth Amata, a researcher at the Kabete station.
"In Meru South, this disease is a constraint on Cavendish types especially Apple banana varieties," says Easton Njeru, a Karlo researcher based in Embu.
Dr Amata advises farmers to observe crop hygiene to reduce disease incidence and prolong economic life of the crop.
"The use of plant resistance is the most effective approach to management of Fusarium wilt and is the most economic and practical long-term option for small-scale farmers in Kenya. However, farmers can use traditional control methods such as crop rotation, fallowing, soil treatment and soil fertility to reduce spreading," she says .
So is the dangerous TR4 strain coming to Kenya soon? The answer depends on whom you ask.
Fazil Dusunceli, an agricultural officer with the FAO, says TR4 could spread across the world only if producers aren't vigilant.
He says farmers have to use disease-free certified planting materials, and avoid any materials or soil that could be infested. "The FAO collaborates with many research institutions and scientists on many aspects to promote the best practices to prevent the spread of the disease," he told the Huffington Post recently.
Dusunceli also notes previous outbreaks spread at snail pace.
For instance, the outbreak that killed the Gros Michel banana, the primary variety grown for worldwide export that the Cavendish replaced—began in the late 1800s but didn't completely wipe out the Gros Michel's commercial viability until the early 1960s.
He feels that today's technology, including the use of tissue culture, could save the Cavendish banana, which is the world's most important export variety, and the one Kenyan farmers are likely to make most money from.
Another report on US media calls it media hype. "The western press is so enamored with the 'Bananageddon, Apocalypse' scenarios because it sells, both for the media as well as the researchers who are looking for money for their GMO research," Dr Agustin B. Molina, Jr., told Modern Farmer, a quarterly American magazine devoted to agriculture and food.
Molina is a researcher for Bioversity International, a global research-for-development organisation focused on sustainable food and nutrition security.
He says for instance, the invasion of TR4 to South and Central America could happen "next year, the next ten years, 20 years, 50 years, or even the next century." Molina points out that for instance, it has been more than 40 years since TR4 first appeared in Taiwan, and it still hasn't reached the Americas or many parts of Africa.
Still, Kenya is not taking chances.
Kalro strongly advises farmers to verify the source of their planting material, and to preferably use tissue culture plants.
"Sourcing suckers from a neighbour can be devastating. They also need to practice good agricultural practices. Farmer sensitization, up scaling of tissue culture laboratories and establishment of farmer owned hardening nurseries would contribute to availability of clean planting material," says Dr Jessica Mbaka, a researcher at Kalro in Thika.
She says farmers suspicious of their diseased bananas can take samples to more than 90 plant clinics located in some parts of the county with concentrations in Central, Eastern and Western Kenya.
These plant clinics are managed by agriculture extension staffs that have undergone extensive training on disease diagnostics, she says.
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