Bananas and Black Sigatoka

Banana production is threatened by various fungi. One of them, Pseudocercospora fijiensis, causes the feared black Sigatoka disease. The fungus is air-borne and occurs worldwide. It affects the leaves of banana plants in all sorts of plantations and results in huge yield losses. The disease also reduces the quality of the fruit, causing premature ripening. The bananas can then no longer be exported and growers lose their income. The Cavendish banana, the most commonly grown banana variety worldwide, is especially susceptible to the black Sigatoka fungus.
Farmers, who can financially afford it, use fungicides or crop protection products to manage black Sigatoka. The effectiveness of these products often quickly reduces, which means that most commercial plantations have to spray increasingly often – over 50 times a year is becoming a common practice. This has a major impact on the environment of the plantations and costs the banana sector some 400 million dollars a year.

Scientists from Wageningen University (The Netherlands) have now unravelled the DNA of Pseudocercospora fijiensis. Gert Kema, Professor at Wageningen University said: “Thanks to the sequencing of the DNA of the Pseudocercospora fungus we are now gaining a greater insight into the interaction between the fungus and the banana plant. This provides us with leads for increasing the sustainability of banana cultivation. For example, the insights offer us opportunities to develop a banana plant that is suitable for production and export, and which is also resistant against black Sigatoka.”
This fresh understanding of the DNA of the black Sigatoka fungus is also providing new information that is useful in the development of more effective and, hopefully, less environmentally unfriendly crop protection products. This could reduce the amount of spraying which, in turn, would improve the quality of life of the people working in the plantations and those who live in the immediate surroundings.

The research has helped identify the segment of DNA of the fungus that forms the basis for a so-called effector: a substance in the fungus that generates a resistance reaction in the wild banana variety Calcutta 4[1]. This wild banana has a receptor which recognizes the fungal substance. In other words, thanks to the receptor the wild banana plant ‘knows’ when it is being attacked and then encapsulates the fungus, preventing the leaves from being colonized further.

The scientists also discovered that tomato plants recognize the substance of the black Sigatoka fungus via a receptor[2]. The wild Calcutta 4 banana and the tomato apparently resemble each other genetically in this regard. A great deal is already known about the tomato receptor, and the gene for the receptor is also available. It would be relatively simple to build these tomato genes into the DNA of banana in order to develop resistant banana plants.

[1] Arango Isaza et al: Combating a Global Threat to a Clonal Crop: Banana Black Sigatoka Pathogen Pseudocercospora fijiensis (Synonym Mycosphaerella fijiensis) Genomes Reveal Clues for Disease Control in PLoSGenetic 2016 
[2] Stergiopoulos et al: Tomato Cf resistance proteins mediate recognition of cognate homologous effectors from fungi pathogenic on dicots and monocots in Proceedings of the National Academy of Sciences of the USA - 2010

Banana flour

An Australian family business has gone bananas after they accidentally discovered a new super food.

For many years Rob Watkins and his family were among the largest banana growers in Australia, specializing in a variety known as Lady Fingers. This variety requires 25-30% more labour to grow than ordinary Cavendish bananas and also has a reduction of 50% less plants per acre due to their height. But week after week Rob would find himself disposing tonnes of beautiful Lady Fingers because they were too big, too straight or too bendy for the supermarket giants. The fruit was perfectly good for eating and packed full of nutrients, but the only species that would flock to the area were local wallabies and cattle. They were eating as many green Lady Fingers their tummies could handle.
Second generation farmer Rob Watkins noticed a dusty substance rise in the setting sun’s rays when he accidentally drove over a cluster of lady finger bananas at the family’s plantation some six years ago. After some experimentation, he and wife Krista produced a small batch of green banana flour and started selling it as a gluten-free alternative through a local cafe.

Orders began pouring in and now the couple’s Natural Evolution business is turning out five tonnes a week from a plant on their property, most of it for export to Japan and Europe.Demand has grown so strongly their 320-hectare property is at capacity and they are bringing in extra bananas from other growers. It has provided a profitable potential for the 500 tonnes of bananas dumped every week in Australia because they are the wrong size or shape for supermarkets.
It can replace other flours for sweet or savoury use. High in vitamins and minerals including magnesium, potassium and vitamin E, it has a wide range of nutritional benefits including high resistant starch content which can strengthen the immune system, speed up metabolism for weight loss, lower cholesterol and help prevent diabetes[1].

[1] De Silva et al: Women with metabolic syndrome improve antrophometric and biochemical parameters with green banana flour consumption in Nutrición Hospitalaria - 2014

Bananas might prevent blindness

Researchers recently published a study, which demonstrates new insights on how bananas make and store carotenoides[1]. Carotenoids which are found at various levels in different banana cultivars, are a important precursors for Vitamin A, which in turn promotes eye health. Their findings could someday help in the development of banana varieties with enhanced health benefits.

Vitamin A deficiency is widespread in Africa and Southeast Asia, causing an estimated 250,000 to 500,000 children to become permanently blind each year, the researchers note. Even worse, half of those children die within a year of losing their sight[2].

To combat vitamin A deficiency, other researchers have been investigating methods to boost carotenoids in bananas, because these compounds—which turn fruits and vegetables red, orange or yellow—are converted into vitamin A in the liver. However, this approach has been hindered by a lack of understanding of how bananas produce and store carotenoids.

The researchers studied two banana varieties to find out why they make very different amounts of carotenoids. They found that the pale yellow, low-carotenoid Cavendish variety produces more of an enzyme, carotenoid cleavage dioxygenase 4 (CCD4), that breaks down carotenoids.

In addition, the orange Fe'i group Musa cultivar Asupina stashes its carotenoids in microscopic sacs during ripening, shifting the chemical equilibrium in the fruit so it can make even higher levels of these substances. The researchers say their work will provide insights for future developments in the biofortification and breeding of bananas that contain higher levels of carotenoids.

[1] Buah et al: The Quest for Golden Bananas: Investigating Carotenoid Regulation in a Fe'i Group Musa Cultivar in Journal of Agricultural and Food Chemistry – 2016 
[2] Nutritional Anemia: Edited by Klaus Krämer, Michael B. Zimmermann – 2007

The Origin of Bananas

[Source: Anne Vézina]

'Where our bananas come from' (1962) was published in the 'New Scientist magazine'. In it, Norman Simmonds wrote that to answer the question on where cultivated varieties of banana come from, “we must go back to Malaysia several thousand years ago, for it was there that men took the first decisive steps in converting the inedible, wild, seedy bananas of the jungles into the lush, parthenocarpic and sterile fruit that we know today”.
Nobody denies that Southeast Asia is a centre of domestication of banana. It’s just that Simmonds should have known better, if only because a few years earlier he had been in a collecting mission to Southeast Asia and the Pacific. During that trip, he visited what is now Papua New Guinea, where he observed a diversity of bananas he had not seen anywhere else. The unusual thing about these edible bananas is that like their wild ancestors they have two sets of chromosomes (diploids)[1], as opposed to the three sets of chromosomes (triploids) found in most cultivated bananas. Because in Asia edible diploids had been largely displaced by the more productive triploids they had given rise to, Simmonds assumed that the diploids he saw in Papua New Guinea had been introduced from Southeast Asia early in the domestication process and had owed their survival to the late arrival of triploid bananas. Except for the unusual Fei bananas – which Simmonds recognized as having been domesticated in the Pacific because their wild ancestor(s) are not found elsewhere – he could not imagine that bananas tracing their origin to Musa acuminata alone, or hybridized with Musa balbisiana, had been domesticated outside Asia.

Subsequent genetic analyses and the discovery of 7,000-year-old banana phytoliths[2] at Kuk Swamp in the highlands of Papua New Guinea, now a UNESCO World Heritage Site, proved Simmonds wrong. New Guinea and nearby islands, including the Solomon Islands, are definitely centres of domestication of banana.

Analysing the genetic make-up of hundreds of banana cultivars revealed that more than one subspecies of Musa acuminata have been implicated in the domestication of bananas. Since these subspecies occupy distinct geographic regions, different subspecies at various stages of domestication must have been moved around in order to come into contact and hybridize. It means that the meeting of Malaysian and New Guinean bananas, among others, was facilitated by people sharing genetic resources.

Starting 2,000 to 4,000 of years ago, the ancestors of Plantains and East African highland bananas went west to Africa, where they continued to diversify, making Africa a secondary centre of diversity. In the other direction, many of the New Guinean bananas were taken east by seafarers, eventually landing in Hawaii. And maybe South America, but that’s another story.

[1] Humans also have two sets of chromosomes, one inherited from the mother and the the other from the father
[2] Phytoliths are microscopic stones made of silica that form in plant cells and are used as archaeological markers for plants that, like domesticated bananas, do not produce seeds and pollen. To see what they look like, See here.

Cypriot Bananas

The de facto division of the island in 1974 left the Turkish Cypriot community in the north in possession of agricultural resources that produced about four-fifths of the citrus and cereal crops, two-thirds of the green fodder, and all of the tobacco. The south retained nearly all of the island's grapegrowing areas and deciduous fruit orchards. The south also possessed lands producing roughly three-fourths of the valuable potato crop and other vegetables (excluding carrots), half the island's olive trees, and two-thirds of its carob trees.
The climate on Cyprus and neighbouring Greek islands like Crete is perfectly suited for growing bananas. Bananas grow rather unruly on pretty much the whole of island Cyprus, but are grown primarily on banana plantations around Paphos on the southwest coast of Cyprus and the Güzelyurt area in Turkish Cypriot territory.

They stretch along the coast up to the mountains. All products are supplied to the domestic market and have good demand. It has been found that the young banana leaves can help to heal burns and wounds.

Most of the harvest is destined for Cypriot consumers. Smugling cheaper South-American bananas to Cyprus via northern Turkish-Cyprus is rife.

Van Rees participates in the Malawi Tea Revitalisation Programme 2020

Van Rees Tea, part of Acomo, has signed a Memorandum of Understanding (MoU) and thereby declared their intentions to support the Malawi Tea Revitalisation Programme 2020. This large-scale industry programme has the objective to achieve a competitive industry where workers earn a higher living wage and smallholders are thriving.

Malawi is an important tea origin for Van Rees and have had an office there since the early 1970s. Currently Van Rees is one of the main buyers of Malawi tea in the weekly auction. The tea from Malawi provides a livelihood for the many tea workers, smallholders and their families. Various companies in the tea industry have acknowledged that the living wages in Malawi are relatively low and strive to act on it.
Managing Director of Van Rees Group, Maarten Obbink, stated that this ambitious programme is broadly supported and hence an opportunity for the industry to really achieve an impact. Every company has its own role in the supply chain and they have to work together to make it a success.

Van Rees believes that only an industry that creates value for all its actors will remain successful in the future and hence will be truly sustainable.

A noteworthy banana: Karat

The Federated States of Micronesia (FSM) is an island nation in the Pacific made up of four states: Yap, Chuuk, Pohnpei and Kosrae. Pohnpei has a rich diversity of bananas, estimated at some 50 cultivars[1].

However, its main claim to fame is the nutritional value of the orange-fleshed bananas, many of which belong to a group of unusual bananas called Fe’i. Fei bananas are believed to originate in the New Guinea area but have been found from the Molluccas, in Indonesia, to Tahiti in the east.
Karat bananas
When American nutritionist Lois Englberger moved to Pohnpei in 1997, conditions related to vitamin A deficiency (VAD) had started to emerge in children. To help alleviate the problem, brought about by the consumption of nutrient-poor imported foods, she went on a search for local foods that used to protect islanders against VAD. Acting on information that Karat bananas used to be a traditional infant food, Englberger and her colleagues found that they are rich in beta-carotene, which the body converts into vitamin A.

Since then, Karat bananas have been at the forefront of campaigns led by the Island Food Community of Pohnpei (IFCP).

[1] Daniells et all: Pohnpei banana varieties - a work in progress. See here.

Bananas and Climate Change

Climate change cannot be denied anymore (although some silly scientists and politicians still do) and it will have a profound effect on bananas. Grown throughout the tropics and subtropics, bananas are a key source of food, nutrition and income for millions of rural and urban households.

They are a staple crop in many countries. In some countries in central Africa, people consume up to 11 bananas per day and in Uganda, the local word for bananas – matooke – means food.

So, what will happen if temperatures keep rising, rainfall will become increasingly erratic and the levels of CO2 keep accelerating at the same pace as it does now?
Especially in the tropical regions, yields of certain crops will decline, but the banana may be lucky. Research shows that by 2070 land area suitable for bananas will increase by 50%. Increasing annual temperatures will make conditions more favourable for banana production in the subtropics and in tropical highlands[1].

So with higher temperatures bananas could be grown in more areas. But these higher temperatures mean an increase in water demand, which is projected to increase by 12-15%. And higher temperatures may also threaten those crops, such as coffee, that are often grown with bananas. Farmers who grow banana as a secondary crop, may abandon banana when climate change makes coffee cultivation less viable.

Which suggests that all is not well for the banana.

[1] Climate Change and Food Systems: Global assessments and implications for food security and trade (Edited by Aziz Elbehri) - 2015. Downloadable here.

Banana Freckle Disease

Banana Freckle Disease is caused by a fungus that has two distinct forms (and names): Guignardia musae (telomorph) or Phyllosticta musarum (anamorph). Banana Freckle Disease infects the leaves and fruits of bananas. There are several different strains of the fungus that are able to infect different banana varieties around the globe.

Like, Panama Disease/TR4, it is entirely possible that each strain of the fungus has evolved to live symbiotically with a specific variety of a banana in a specific environment. Transplant a variety to another country or continent and the Banana Freckle Disease will show its evil face. Transplant another variety to a plantation that seems free of infection and the Banana Freckle Disease will erupt to destroy a crop. In the absence of chemical control, there is about a 80% yield loss.
Symptoms of the Banana Freckle Disease include yellowing of the tissue and formation of small dark brown spots on the leaves and fruit. Within the spots, traces of the fungus can be spotted. The most characteristic symptom of Banana Freckle is a sandpaper feel to the infected (spotted) leaves and fruit when rubbed between your fingers. Banana Freckle is easily propagated and spread from plant to plant via water droplets and movement of infected tissue or fruit.

Management of the disease consist of cutting out infected leaves, the paper bag method, fungicide application, and proper sanitation techniques. This devastating disease is extremely relevant for the major banana exporting countries of the world. Banana Freckle disease needs to be carefully monitored in order to prevent further spread of the disease.

Australia is trying to eradicate the Banana Freckle Disease by destroying all infected banana 'trees'.

More information about the Autralian initiative can be found here.

Banana Xanthomonas Wilt Resistant Bananas

Banana Xanthomonas Wilt (BXW) is also known as banana bacterial wilt (BBW) or enset wilt. It is a bacterial disease caused by Xanthomonas campestris and it is one of the most devastating diseases that can attack a banana.

After being originally identified on a close relative of banana, Ensete ventricosum, in Ethiopia in the 1960s, Banana Xanthomonas Wilt appeared in Uganda in 2001 affecting all types of banana cultivars. Since then Banana Xanthomonas Wilt has been diagnosed in Central and East Africa including banana growing regions of Rwanda, Congo, Tanzania, Kenya, Burundi, and Uganda. This wilt attacks all cultivars of banana causing up to $2.2 billion estimated annual loss.

A bacterial ooze is excreted from the plant organs and this is a tell-tale sign that Banana Xanthomonas Wilt may be present. Common symptoms on the fruit include a yellow-orange internal discoloration and premature ripening of the fruit. Other symptoms include a gradual wilting and yellowing of the leaves plus wilting of the bracts and shriveling of the male buds.
[Image: blog.plantwise.org]
The spread of Banana Xanthomonas Wilt threatens the livelihood of millions of African farmers who depend on banana for food security and income. There are no commercial chemicals, biocontrol agents or resistant cultivars available to control Banana Xanthomonas Wilt.

The development of disease resistant banana cultivars remains a high priority and scientists have tried to insert genes from foodstuffs that have shown resistance to Banana Xanthomonas Wilt. Now, a banana, infused with plant ferredoxin-like amphipathic protein (Pflp)[1] or hypersensitive response-assisting protein (Hrap)[2] from green pepper, have exhibited strong resistance to Banana Xanthomonas Wilt in both laboratory and screenhouses. The Hrap and Pflp genes work by rapidly killing the cells that come into contact with the disease-spreading bacteria, essentially blocking it from spreading any further. The mechanism, known as Hypersensitivity Response, also activates the defense of adjacent and even distant uninfected plants leading to a systemic acquired resistance.

Field trials are now being held.

[1] Namykwaya et al: Transgenic banana expressing Pflp gene confers enhanced resistance to Xanthomonas wilt disease in Transgenic Research - 2012
[2] Tripathi et al: Expression of sweet pepper Hrap gene in banana enhances resistance to Xanthomonas campestris pv. musacearum in Molecular Plant Pathology - 2010

Some banana cultivars in Indonesia show Panama disease resistance

During the summer of 2014, samples were collected of Bananas affected by Panama disease on three different islands. Research by Nani Maryani, PhD student at Wageningen University, focussed on areas surrounding the rain forest for infected banana plants. They collect parts of the banana corn, the leaf and soil samples for analyses.

Interestingly, the researchers identified some cultivated bananas among the huge banana diversity they have observed during the sampling expedition that are seemingly resistant to Panama disease in Indonesia.
Pisang Klutuk Wulung

These include Pisang Klutuk (Musa balbisiana) and Pisang Mahuli that were never affected throughout the expedition at various geographical sites. In addition, various indigenous wild banana species such as Musa bornensis, Musa acuminata var. Falava and Musa acuminata var. bantamensis were also found resistant in wild forest habitats.

These species and varieties will undergo in-depth analyses in further laboratory experiments in Indonesia and Wageningen.

Feel free to contact Nani about her PhD project and on-going work here.

Bananas and your Mind

Sometimes people selfmedicate. I personally have friends who take speed to calm down. From a medical perspective that makes sense, because it is practically the same molecule as methylphenidate (or ritalin). Others use (or misuse) products to forget, but even that can help to prevent or mediate (the effects of) a depression.

Now, scientific research has been published that suggests that creative people sometimes comsume certain foodstuffs to counter writersblock or simply overcome another type of temporary lack of inspiration.
The researchers tried to understand whether creativity is enhanced by the amino acid L-tyrosine, a known precursor of the neurotransmitter dopamine. The more dopamine, the more brain activity one should expect to see and the higher the level of creativity could be, so the scientists thought.

In the end, there appeared to be no evidence that L-tyrosine had positive effects on divergent (creative) thinking or, as scientists like to tell you: brainstorming. But it did result in an marked improvement in the convergent (analytical) thinking. Because convergent thinking needs more (mental) energy, researchers suggest that the L-tyrosine supports this process[1].

Now, of course, you think that you should dash to the nearest drugstore and buy yourself a jar of L-tyrosine. But no, that is not necessary at all, because L-tyrosine is simply one of the 22 amino acids that your body needs and it hides itself in a lot of common foods, such as chicken, fish, milk, cheese, peanuts, avocados and - yes - bananas.

Which means that, if you will have a difficult meeting with your boss (or your subordinates), you’ll simply need to consume a banana before the meeting.

[1] Colzato et al: Food for creativity: tyrosine promotes deep thinking in Psychological Research - 2014

Chinese banana harvest destroyed by typhoon

Authorities in Nanning town, in the Zhuang du Guangxi region are trying to save some part of this year's banana harvest that has been severely damaged by typhoon Rammasun.

On Tuesday July 22, 2014, over 1.6 million banana trees in Tanluo were knocked over by the storm, with financial loss at over 58 million Yuans, which is about € 7 million. The Mayor of the town, Wei Shiguo, took part in the volunteer action to save damaged banana trees. Local authorities have been in contact with banks to offer loans to the banana producers that are victims of the typhoon.
“This financial support will allow them to restart a plantation and actively revive their agricultural work’’ underlined Wei.

Bananas are one of the most important agricultural products in the region. Tanluo used to be know as “the banana town’’.

Storm creates havoc in Bananas

Last week storms and heavy rains affected around 15000 hectares of banana plantations in the Northern Colombian Uraba region. According to official sources, more than 4000 hectares of banana trees were utterly destroyed.

A week later, all other banana countries in Latin America already felt increased demand due to these problems with the banana production in Colombia. For example, in Ecuador, the price has increased by 1.5-2.0 USD compared to the previous week.

Analysts expect that in the nearest half of the year, Colombia will sustain a loss of around 4 million boxes of banana.

Right now producers are hoping for government support in this issue in order to recover the nations banana industry.

Bananas, Fusarium and Chinese Leek

The banana is under serious threat. A fungus, Fusarium oxysporum cubense Tropical Race 4 (TR-4) can potentially wipe out the banana as we know it in a few short years.

Scientists are working around the clock to save one of the world’s most important foodstuffs. Most of these scientist are trying to create a resistant type of banana via the genetic route. Because the current banana, the Cavendish, does only contains seeds on extremely rare occasions, it cannot begrown in the usual way. But this all takes time, and time is a currency we do not have.

So, maybe we need to look for other temporary solutions to safeguard our banana. Chinese research indicates that Chinese leek (Allium tuberosum) has an inhibitory effect on the fungus that creates Fusarium wilt and may be an efficient way to control the disease until science has created a new variety of banana that is resistent to Fusarium oxysporum TR-4.

Adopting a rotation system with Chinese leek and banana, reduced the Fusarium wilt incidence and disease severity index by as much as 88%-97% and 91%-96%, respectively, and improved the crop value by 36%-86%, in an area heavily infested by Fusarium oxysporum TR-4 between 2007 and 2009.

Crude extracts of Chinese leek completely inhibited the growth of Fusarium oxysporum on Petri dishes, suppressed the proliferation of the spores by 91% and caused 87% spore mortality.

The findings of this study suggest that Chinese leek has the potential to inhibit Fusarium oxysporum growth and Fusarium wilt incidence. This potential may be developed into an environmentally friendly treatment to control Fusarium wilt of banana[1].

[1] Huang et al: Control of Fusarium wilt in banana with Chinese leek in European Journal of Plant Pathology - 2012

A noteworthy banana: Musa indandamanensis

Wild banana species are largely distributed in some tropical rainforests, wet evergreen forests to deciduous forests of low rain fall zones. The major centres for these wild bananas can be found from India to Indonesia.

The Andaman and Nicobar Islands in the Indian Ocean are little known. It is also a region where the wild bananas have not been explored systematically because it has received little attention from taxonomists.
The low lying Little Andaman has widespread rainforests. The island has a warm and humid tropical climate, with the temperature ranging from 18° to 35°C. It receives heavy rain fall from monsoons with the average annual rain fall ranging from 3000 to 3500 mm.
During explorations, L. J. Singh found a new species of banana and he named it Musa indandamanensis, in honour of the island. The peel and pulp colour of the fruit becomes yellowish orange at maturity with a circa 3.5 centimeter long stalk and many seeds[1].

[1] Singh: Musa indandamanensis L. J. Singh: A New Species (Musaceae) from the Bay Islands, India in Taiwania - 2014. Pdf here.

Brazil in search of new banana varieties resistant to Panama Disease

The Brazilian Ministry of Agriculture, Livestock and Supply stated that the measures taken to prevent the entry of the Panama Disease into Brazil should suffice. It must be wishful thinking (or else a meaningful disregard for the obvious facts), because the disease is causing the banana plantations in Asia and Africa to lose billions of dollars.

According to Alexei Dianese, researcher from Embrapa Cerredos, it is only a matter of time before the pest arrives in the Americas.
Dianese stated that they had reasons to worry. According to him, the fungus could destroy a banana plantation in a few months. Once it reaches the ground it penetrated the roots and makes them rot, then, as the leaves no longer get nutrients, the plant dies.

"It depends on the location and the variety of the plants. It might take longer if the soil is well drained. For example, the apple banana variety, which is extremely susceptible to the Panama disease, developed the typical symptoms of the Panama disease in their second year, when the plants were 1.80 meters tall, then, they died," he explained.

Embrapa is betting on developing new varieties resistant to the disease via genetic improvements. Two years ago, Embrapa, in collaboration with universities of the countries where the disease has already spread, started an investigation. According to the Dianese, the prata (Musa x paradisíaca) and apple varieties, which account for 70% of Brazilian production, are the most susceptible varieties to this disease.

Banana Chips

Banana chips are slices of bananas that are or dried naturally or deep-fried. The are considered a delicacy in southeast Asian Countries, but are also exported overseas to Europe and North-Amrica.

The banana chips are usually made from the Saba and Cardava varieties of Musa sapientum. The bananas are picked in their mature green stage, peeled, washed, sliced and fried in vegetable oil to get the crispy and golden end product. Often, a syrup containing a bit of honey is added before drying.
You can dry the chips naturally but the slices will turn brownish and rather soggy (and sorry) looking.

The vast majority of the banana chips originate from the Philippines, but they are also a delicacy in countries such as Vietnam, Indonesia (kripik pisang) and India.

Are banana chips a healthy alternative to other snacks? Yes, bananas are very healthy, but the chips are deep-fried in oil and that is detrimental to the health potential of the chips. Consume with care if you're on a diet.

The quest for resistance against Panama Disease/TR4

Bananas from remote regions of Uganda are now tested at Wageningen University in The Netherlands to see if they might harbour (some) resistance against the feared Tropical Race 4 of the Panama Disease that is currently raging around the globe.

Scientists are engaged in a race against time to find a variety of banana that is resistant. Meanwhile, the future seems bleak.

A Noteworthy Banana: Musa Serpentina

Musa serpentina is named after the sinuous shape of its rachis, the ‘shaft’ of the main, flower-bearing section. In Thailand its native name, Kluai Nakkharat, means ‘serpent king banana’.
This species was only described as late as 2011 and was discovered[1] in western Thailand along the border of Myanmar (Birma). In that specific area other variants, such as Musa acuminata and Musa laterita, are also growing abudantly. Because Musa serpentina possesses characters of both of these species, it has been suggested that it is a hybrid rather than a seperate species. It has been observed in open mixed deciduous forest along stream banks and roadsides, and at altitudes varying between 240 and 570 meters.

[1] Swangpol et al: Musa serpentina (Musaceae): a new banana species from western border of Thailand in Thai Forest Bulletin - 2011

Your favourite food may be under attack

Having to rely on a single type or variety of foodstuff is dangerous business.

In the mid-19th century, a disproportionate share of the potatoes grown in Ireland were of a single variety, the 'Irish Lumper', because that flourished in the poor Irish soil. Crops failed for several years in a row in Ireland, the Scottish Highlands and – later – in mainland Europe.

From 1845 until 1857 over a million Irish died and forced another two million to emigrate (read: flee) to unaffected countries like the US because their potatoes were under attack from a strain (HERB-1) of a fungus-like organism, Phytophthora infestans.

You might think that modern insecticides or fungicides, algicides, and all other types of biocides are potent enough to counter all possible threats. But they are not.

During the middle of the last century, the Panama disease virtually wiped out the single most important banana variety, the ‘Gros Michel’, and we are now forced to eat the lesser tasting ‘Cavendish’. But that one is now also under threat from a new, mutated version of the Panama disease. See here for more banana news.
But there’s more: six major types of pineapple exist but we grow and eat only one cultivar, the ‘Smooth Cayenne’. Cultivation of all the other varieties is dwindling. The ‘Smooth Cayanne’ started its life scarily spiky, green on the outside and, more often than not, sour and fibrous within. In 1996, a new hybrid appeared: the Gold Extra Sweet pineapple (or MD-2), the first of a new type of low-acid pineapple. But it still was a ‘Smooth Cayenne’.
[Image by Asit Ghosh| Tommy Atkins]
The mango is suffering similar genetic erosion. The ‘Tommy Atkins’, which dominates the world export trade of mango’s because it is valued for its very long shelf life and because it has a good tolerance of handling and transportation with little or no bruising or degradation. But the 'Tommy Atkins' may have all those positive traits, it certainly does not have the same exquisite flavour as that of a ‘Chaunsa’, which is still grown in Pakistan.

Honduras: Banana production down 40%

Currently, Honduras exports about 20 million cases of bananas and these delivered revenues of $458.3 million dollars in 2013. Only ten years ago these shipments exceeded 40 million cases. Which means that there’s something seriously wrong with the banana in that Caribbean country.

The problem is that the Hondurese plantations were created by a system of agriculture which is ominously called ‘slash and burn’. It is the process of cutting down the vegetation in a particular plot of land, setting fire to the remaining foliage and using the ashes to provide nutrients to the soil for use of planting food crops.
The cleared area can only be used for a relatively short period of time, then the soil is exhausted of its nutrients and should then left be alone for a longer period of time so that vegetation can regenerate itself and the soil.

In Honduras, the soil of the banana plantations is depleted and compacted. In the olden days, the giant American corporations simply bribed a government official and got hold of a new stretch of jungle to start over again. Now, to get hold of new land, the Honduran companies are in urgent need of over $30 million dollars within the following four or five years to reactivate the crop.

It may not be quite enough or even quickly enough because Panama Disease is on its way.

Where did the coconut originate?

The origin of the coconut (Cocos nucifera) is subject to controversy. Now, the coconut palm has a worldwide distribution, though its presence is limited to the tropics. But that very distribution makes it difficult to pinpoint its original home. So, where did the coconut originate?

In his 1901 book ‘The Origins and Distribution of the Cocoa Palm’ the American biologist O. F. Cook tried to prove that the coconut palm originated from South America. His theories were based more on conjecture than on sound science. He claimed that ‘… evidence of the existence of the banana in prehistoric America is equal, if not superior to that here presented for the cocoanut.’ Sure, that might be true, but it surely proves nothing. Others have tried to prove that the species originated in the Indian Ocean.
Even now, proponents of a South American origin fail to explain why it is not indigenous there and why it shows greatest diversity in southern Asia. On the other hand, proponents of an Asian origin must explain why there are no Asian Cocoseae and why the closest botanical relative to Cocos is in South America.

Both hypotheses share the common problems of how, when, where and in what directions long-distance dispersal occurred. These difficulties are resolved[1]  by accepting that the coconut originated and dispersed by populating emerging islands of the coral atoll ecosystem in the Pacific Ocean.

Driven by currents, the coconuts can drift long distances, and when lifted by wave action onto virtually sterile, soilless coralline rocks just above sea level and exposed to the sun, the nuts will quickly germinate, root and establish themselves in large populations. But currents alone cannot explain the entire pattern of dispersal of the coconut palm but that is consistent with human introductions of Pacific coconuts along the ancient Austronesian trade routes connecting Madagascar to Southeast Asia[2].

Therefore, the evidence supports a theory of a Pacific origin of the coconut palm.

[1] Harries et al: Long-distance dispersal of the coconut palm by migration within the coral atoll ecosystem in Annals of Botany - 2014
[2] Gunn et al: Independent origins of cultivated coconut (Cocos nucifera L.) in the old world tropics in PLoS One - 2011

Pineapples: same story, same risk, other diseases

We know that the banana is under serious threat. Worldwide, the most cultivated cultivar of the banana is the ‘Cavendish’. It replaced the ‘Gros Michel’, which succumbed to the Panama Disease in the 1950s. The ‘Cavendish’ was chosen because it was able to resist the fungus that killed the ‘Gros Michel’. But the fungus has mutated and the new version, called Fusarium tropical race 4 (TR4), originated in Taiwan and is quickly creating havoc in plantations in Asia, the Middle East and – recently – Africa.

Because all commercially grown bananas were identical cultivars of the ‘Cavendish’, they are at risk of worldwide extinction, creating mass unemployment which will be quickly followed by starvation of the population of banana producing countries.
[Scarlet pineapple]
What about pineapples, you might ask. Like bananas, pineapples suffer from the same problem because one cultivar, the ‘Smooth Cayenne’, is grown around the world. It does not have the spiny edges of other types do have, it has a high yield, adapts well and has good characteristics for canning. The pineapple industry of the world is therefore dominated by the ‘Smooth Cayenne’, which is used both for fresh fruit and for processing.

Such a near-total reliance in crop cultivation is uncommon and is made even more unbelievable by the fact that the ‘Smooth Cayenne’ has been the backbone of the global pineapple industry for more than a century. First collected by Samuel Perrotet in 1919 in French Guiana, it was rapidly distributed and planted in other geographical regions.

A virtual mono-culture also means that diseases may appear in far-away corners of the globe and these can spread like wildfire because of the fact that all these pineapples are genetically the same. Which is exactly what is happening now: diseases like (bacterial) heart rot or (fungal) pineapple black rot are already widespread and are now common and destructive pineapple diseases in the world. In Malaysia, both bacterial heart rot and fruit collapse caused by Dickeya spp. are endemic, with field crop losses recorded of up to 40 per cent. It is feared that the disease may spread to Australia’s Queensland, that has a pineapple industry worth A$80 million a year and underpins more than 1,000 jobs. Hawaii has the only commercial pineapple crop in the USA and thus represents the entire U.S. industry but when bacterial heart rot of pineapple was reported in Hawaii in 2003 and reoccurred in 2006, it was a serious blow to the industry.

Merger of Banana Companies: Flight or Fight?

Chiquita and Fyffes announced today that they will merge their companies into one. The agreement creates a global banana company with approximately $4.6 billion in annual revenues.

The press release focuses conveniently on the combined strengths of ChiquitaFyffes. It should generate more profits for the shareholders, but it will also create ‘more opportunities and capitalize on both the growing fresh food business and health and wellness trends by more effectively utilizing its geographical footprint and expanded distribution channels.’ Yes, it's all good news. ChiquitaFyffes will become the largest global entity in the banana category with sales of more than 160 million boxes annually.
The problem is, of course, that the banana itself is under threat and both companies will undoubtedly envisage huge problems in the forseeable future. If the dreaded Panama Disease spreads to the Americas – and it eventually will do so – the banana itself may be doomed if a replacement variety is not available in time.

If harvests collapse, then prices of bananas will soar and there might not be a single banana to sell by these companies. Then then may be forced to focus more on having even stronger positions in the melon and pineapple market segments. At present ChiquitaFyffes is the number one importer in the U.S. and number three distributor globally.

Which means that a merger is effectively the only way to survive. Unless they forgot to mention to their shareholders that pineapples might have the same problem as the bananas have: one variety, the Smooth Cayenne, is extensively cultivated in Hawaii, Philippines, Australia, South Africa, Puerto Rico, Kenya, Mexico, Cuba and Formosa. It takes only one dieseas causing agent...

The 'correct' way to peel a banana

Science tells you that we humans and monkey's share a common ancestor. Maybe our ancestors should have paid more attention to our simian peers, because we have peeled a banana the wrong way since time immemorial.

A monkey opens the banana at the other end so it bruises less easily and allows you to eat all the way to the end of the fruit.
This technique proves that monkeys still have the advantage over humans in some ways and this handy skill will means you will never peel a banana in the same way again.

Bug-infested Bananas in Costa Rica

It is not good news when a government declares a national crop emergency for bananas, but Costa Rica did just that in December 2013.

Bananas are one of Costa Rica’s most important agricultural exports but the crop is at risk over the proliferation of mealybugs (Dysmicoccus spp.) and scale insects across the country’s Atlantic banana-growing regions. The insects sap nutrients from banana plants, leaving them weakened and causing dark stains on the fruit.

Experts were aware of the problem but the pest is getting a bigger and bigger problem and is threatening Costa Rica’s multi-million-dollar banana industry as climate change bolsters insect populations.
Climate change, by affecting temperature, favors the conditions under which the insects reproduce,” said Magda González, director of Costa Rica’s State Phytosanitary Services (SFE), “as do changes in rain patterns”. She estimated that these conditions could shorten the bugs’ reproduction cycle by one third.

González estimates that the pests have affected some 24,000 hectares of banana fields to varying degrees. The insects weaken the banana plant, lowering production, and can cause blemishes on the fruit that exporters might reject. Upwards of 20 percent of a banana shipment could be rejected due to quality concerns caused by scale insects.

As part of the emergency decree, producers will be temporarily allowed to import and wrap banana bunches with bags laced with the pesticides buprofezin and bifenthrin.

Bananas at risk in India

While the origin of the banana lies elsewhere, India was an ‘early adaptor’ and is now home to many varieties of bananas. Ancient Buddhist texts from around 600 BC mention the banana for the first time and describe it as a highly nutritive food. These texts describe a beverage derived from banana which the Buddhist monks were allowed to drink. Travelogues of 327 BC mention that the Alexander the Great discovered the banana when he campaigned deep into the valleys of northern India. In the year 200 AD, China had an organized system of banana plantations, but at that period in the history of China, everything and everybody was highly organized.

The banana is an important crop for subsistence farmers and ensures a secure and year-round supply of food or income. It supports livelihood of millions of people with a total annual production of some 17 million tonnes. Banana contributes 37% to total fruit production and account for 2.8 percent of India’s agricultural GDP.
Although India grows at least 670 different varieties, the variety of banana that is grown the most is the Cavendish. These bananas are mostly produced on a small scale and the large increase in production is the result of ever more dense planting, the use of tissue-cultured seedlings and drip irrigation.

But all this is at risk because of the spread of the Panama Disease. The Panama disease is already found in all banana-producing regions of India, especially in north eastern region. To counter the disease, heavy usage of fungicides is required, something the relatively poor smallholders cannot afford. That means that millions of people are at risk of losing their livelihood and may start to suffer from extreme poverty and malnutrition.

Caribbean Fairtrade banana farmers savaged by storms at Christmas

Torrential rains and severe winds battered the Caribbean Islands of St Lucia, St Vincent and the Grenadines and Dominica for over 24 hours between Christmas Eve and Christmas Day devastating rural communities and banana production. The government has declared this a level 2 disaster, meaning that they now need external support to respond to the destruction caused by the storm. Our partner, the Caribbean Farmer's Association, WINFA, are appealing for help on behalf of the estimated 700 small farmers affected.
Floods and landslides severely damaged roads, bridges, sanitation supplies and housing. Hospitals have been flooded and several people lost their lives. The agricultural sector - root crops, vegetables and banana production - also suffered huge losses, threatening the livelihoods of thousands.

Most Caribbean banana production is certified Fairtrade and these small family farmers export all of their bananas to the UK. During the storm 700 farms were flattened by flood waters. WINFA estimate, for example, that 36% of banana production on St. Lucia has been affected. Pack houses and other infrastructure and supplies necessary for Fairtrade production and export have been damaged. Storm damage has also resulted in heavy soil loss and communities now have limited access to drinking water. Agricultural workers have no short term income. These family  farmers urgently need planting materials and seeds, basic supplies such as water, food and clothing, equipment to remove hazards and salvage re-usable resources (including safety equipment, tools, chain saws etc.) as well as training in sustainable land use and soil and water conservation.

Donate now here to help family farmers respond to this disaster and replant their crops.

Panama Disease spreads (further and further)

Only a couple of weeks ago I wrote an article on this site here that scientists from Wageningen University in the Netherlands had demonstrated that Panama Disease – caused by the fungus Fusarium oxysporum cubense TR4 – had migrated from southeast Asia to Jordan. The disease was first detected in Asia in the 1990s, and is now found in Taiwan, Indonesia, Malaysia, the Philippines, China and northern Australia.

I feared that major banana-producing countries in Africa and Latin America were also under increased threat. Now, those fears seem to have materialized because TR4, the destructive strain of Panama Disease, has been discovered on Cavendish bananas in Mozambique in early 2013[1].
All sites where the disease was found have now been isolated, the affected plants destroyed, and appropriate phytosanitary measures have been implemented to prevent the disease from further spreading.

“I will not be surprised if it pops up in Latin America in the near future,” says Gert Kema, a Fusarium researcher at Wageningen University. That region, along with the Caribbean, accounts for more than 80 percent of banana exports.

As usual, the effects of the outbreak are downplayed by government officials and Dr Serafina Mangana, Head of Mozambique's national plant protection organization (NPPO), is on record saying that “the outbreak is limited to a few fields on the farm”.

Yeah, right.

[1] Joint statement issued by the Mozambique Department of Agriculture, Matanuska, IITA, Stellenbosch University and Bioversity International: New strain of banana disease arrives in Africa

A noteworthy banana: Musa haekkinenii

Musa haekkinenii is a wild species of banana that appears to grow only in mountainous forests of northern Vietnam but in reality its precise distribution is not known because these days it is found only as an ornamental in some private gardens and nurseries. Expeditions to possible growing sites in 2008 and 2010 failed to locate any wild populations.
[Image: Markku Häkkinen]
This species has been named in honour of Markku Häkkinen, a Finnish botanist who was a former sea captain but became interested in bananas. Häkkinen is now considered one of the world's foremost experts on the taxonomy of bananas. He has described forty-six out of the seventy known species of wild bananas and three species have been named after him: Musa haekkinenii, Musa velutina markkuana and Musa markkui.

Musa haekkinenii is locally referred to as Chuoi rung hoa do (‘red wild banana’) and it is only a rather smallish species (1 to 1.5 m high) that has an erect inflorescence and a slender pseudostem (3-4 cm in diameter). Its leaf habit is semi-erect and it produces 2 to 6 suckers close to the base of the mother plant. The persistent male bracts are bright scarlet on both surfaces and curved downward. The fruit position is oblique in relation to the axis.

Panama Disease in Bananas

Panama Disease (also known as fusarium wilt of banana) is a dreaded infection of bananas caused by a funges called Fusarium oxysporum cubense. This fungus belongs to an extended species with more than 100 different subspecies.

The fungus invades the vascular tissue (xylem) through the roots causing discolouration and wilting. The problem of this fungal disease is that the pest cannot be managed effectively with pesticides, fungicides or biocides. The only way to counter this threat is to create resistant cultivars via genetic modification.
The fungus itself acts almost like the elusive subtypes of the Influenza virus and various strains of the fungus have evolved to attack different types of banana. These strains or subtypes that are pathogenic to bananas are classified into races based on the differential response of cultivars.

At this moment different four races are known, although some suggest that more races may exist. The problem is that these races are simply based on their differential response on cultivars and this means that there is no real scientific base for the current division. Novel Influenza subtypes are identified using accepted scientific analysis and that should also be the route forward with Fusarium oxysporum cubense.
[Image: K. Nishimura]
Race 1 attacks cultivars like Gros Michel (which caused the 20th century epidemic that heralded the demise of the Gros Michel), Pome, Silk and Pisang Awak.
Race 2 preys on Bluggoe and closely related cooking cultivars.
Race 3 was reported to affect Heliconia species and to a lesser extent Gros Michel and seedlings of Musa balbisiana.
Race 4 strains attack Cavendish cultivars, as well as the cultivars that were also susceptible to Race 1 and Race 2.

Banana, Plantágo and Plantain

Worldwide, there is some agreement that regular edible bananas should be called bananas, while starchy bananas that are usually baked or cooked should be called plátanos or plantains.

Platáno is a Spanish word that originally was not linked to the banana. It was used to describe a small family of trees, the planes or plane trees. These trees are indigenous in the northern hemisphere. The origin of the scientific name of these species, platanos, is Greek: πλατσυός. That word can be traced back to platos (πλατός), which means ‘broad’ or ‘wide’. Now we can easily understand why the Spaniards decided to call the banana shrub platáno; it has very broad leaves.
If you might further be interested in the origin of the word ‘banana’, I can help you here because the Arabic word banan translates as ‘(human) finger’. Because the bananas were introduced from India to Afria and Arabia by Indian or Arab seafarers, the Arabs borrowed the name from Egyptian mauz or mous via Sanskriti word moka and eventually it became mauz in Arabic.

Carl von Linné (1707 – 1778) or Carolus Linnaeus in his latinized form used the Arabic mauz to describe the family and name it Musa. However, a minority of scholars think that Musa is derived from Antonio Musa (63-14 BC), the physician to Emperor Augustus.

A noteworthy banana: Plátano de Canarias

The Plátano de Canaria can be translated as ‘Banana from the Canary (Islands)’ and it is both the name of the banana and the trade name under which these bananas are marketed. This banana is also noteworthy because the European Commission agreed in November 2013 to enter the name in the register of protected designations of origin and protected geographical indications. It simply means that no other country may call its bananas Plátano de Canaria.
Banana is the most important crop in the Canary Islands and, after tourism, is the single most important factor contributing to economic growth.

Because the Plátano de Canaria is a general term, it encompasses several banana varieties. The species that grows abundantly on the Canary Islands is the Cavendish (Musa acuminata x M. balbisiana). Other planted cultivars are Gran Enana (Grande Naine), Zelig and Gruesa, a local type of Dwarf Cavendish.

The bananas were introduced on the Canary Island by returning Portuguese explorers. Once the crop was successfully settled on the islands, the visiting Spanish explorers, using the islands as a stop, introduced them to the New World.

Panama Disease spreads (further)

Scientists[1] from Wageningen UR recently have demonstrated that Panama Disease – caused by the fungus Fusarium oxysporum cubense – has now also migrated to Jordan. This means that Panama Disease is becoming increasingly widespread and major banana-producing countries in Africa and Latin America are also under increased threat.

During the twentieth century, tens of thousands of hectares of banana plantations in Latin America were destroyed by Panama Disease. Banana plants died en masse and soils were contaminated for decades. The introduction of the resistant Cavendish banana variety saved the day and clones of the Cavendish banana are now cultivated around the world. Late last century, however, a new, highly aggressive strain of the fungus was discovered in Southeast Asia. Tropical Race 4 (TR4) is starting to have a huge effect on the Cavendish cultivar in Southeast Asia and there is currently no way to protect the banana.
A few years ago, suspicions arose that some banana plantations in Jordan could be infected with Panama Disease. These plants developed the same symptoms as banana plants infected with samples from Southeast Asia. Subsequent DNA tests showed that the Jordan strains were identical to TR4, thus demonstrating that TR4 has now spread beyond Southeast Asia.

Relatively few bananas are grown in Jordan – bananas are cultivated on around 1500 hectares – but already 80% of the plantations are infected. It is unclear by which route Panama Disease spread from Southeast Asia to Jordan. Gert Kema argues that it is only a question of time before TR4 reaches Africa, where bananas are an important part of the diet of millions of people.

[1] Garcia et al: First Report of Fusarium oxysporum f. sp. cubense Tropical Race 4 associated with Panama Disease of banana outside Southeast Asia in Plant Disease - 2013

A noteworthy banana: Lakatan

The Lakatan (previously known as Lacatan) is a Musa acuminate and is a so-called dessert or cooking banana.

This banana cultivar originates from the Philippines and it is very much adapted to the humid conditions that prevail on the islands. It thrives best in areas with mean annual temperatures of 26-30oC and is frost sensitive. It will stop growing altogether when temperatures drop below 13oC. It prefers an annual rainfall of about 3000 mm evenly distributed throughout the year, which is therefore about 250 mm a month.
[Image by ilikerareplants.blogspot.com]
In neighbouring countries it is variously known as Pisang Berangan (Malaysia), Pisang Barangan, Pisang Barangan Merah, Pisang Berangan Kuning (Indonesia), Kluai Hom Maew and Kluai Ngang Phaya (Thailand). It was introduced in Jamaica as early 1625, where it became known as Jamaican Red and quickly became one of the most popular bananas. It subsequently spread to Caribbean islands such as Cuba where it is still known as Cuban Red.

The Lakatan is a tall banana shrub with brilliant red-skinned fruits. The plant itself is as visually striking as the fruits: all parts are marked with brilliant shades of red, from the pseudostem to the midribs of the long, broad leaves. The Lakatan can grow up to more than 7 meters in height before bearing a bunch of bananas weighing in at about 10 kilos. These fruits can be used ‘green’ for cooking, but are much better in both flavour and texture when they are allowed to ripen to their full-red or purplish skins.

To conclude: the Lakatan is an excellent variety for growers in humid climates.

Growing bananas in pots

Bananas are tropical herbs and that mean you can run into serious trouble if you want to grow your own bananas and you live in a temperate climate in northern Europe or North-America. Some species of bananas may tolerate some frost but most don’t and you never know how cold it may become in those dark winter nights.

The solution is to grow your banana plants in pots that can be stored indoors during the colder months. You should choose your pot with some care: because bananas are shallow rooted the pot should be wider than taller. That shape will help to stabilize the pot as the plant gains height.
Remember that banana plants require lot of drainage. In its native tropical climate it will get moisture at least once a day but this rain will drain away quickly in the loose soil. To emulate this, the pot must have a moderate distribution of holes in the bottom of the pot and also by choosing a soil that percolates.

Resist the temptation to place rocks at the bottom of a pot. Rocks can adversely affect the soil pH, become a home for fungi, etc. Also, do not place flat-bottomed pots on a flat surface because the moisture will become ‘trapped’ in the pot and that will also be a perfect home for diseases. Raise the pot so it will drain completely by placing it on a few masonry chips or bricks.

Choose a soil that contains a good mix of sands, peat, organic material and perhaps some manure and calcium.

If you want any help when you run into unforeseen problems, there are always very helpful people around at www.banana.org.

Bananas can save your heart and soul

Potassium is crucially important to help your heart beat rhythmically. If you have high blood pressure, heart failure or heart rhythm problems, getting enough potassium is especially important. Although potassium and cholesterol aren't directly related, eating a potassium-rich diet just might lower your cholesterol enough to avoid medication.

Researchers[1] defined low potassium intake as less than 2.4 grams per day and high intake as more than four grams per day. A study of 5,600 men and women over 65 found those with the least potassium in their diet were 1.5 times more likely to have a stroke than those with the most.
If you maintain a healthy diet, there’s no real risk of having levels of potassium that are too low. Problems might arise when you are prescribed diuretics, medications to treat conditions such as high blood pressure, congestive heart failure and kidney disease. They reduce the amount of water in the body but also rob it of potassium.

One large banana will contain around 422 mg of potassium, which means it contributes about one-tenth of the recommended daily intake. As well as being rich in potassium, bananas contain more than a quarter of the daily requirement of vitamin B6. They are also rich in folic acid, making them an important food for women who are (trying to become) pregnant.

Bananas are also a rich source of tryptophane, an essential amino acid. It is a precursor of serotonin, which in turn is a precursor of melatonin. Serotonin regulates our mood and thus our sense of happiness and well-being. Low levels are linked to depression[2]. Melanonin regulates your internal clock and helps you sleep. Low levels are linked to sleeplessness.

This all means that regularly eating a banana helps maintaining a healthy beating heart, while at the same time keeping you happy and giving you a good night’s sleep.

Maybe we should alter the age-old saying ‘an apple a day keeps the doctor away’ to ‘a banana a day keeps health problems at bay’.

[1] Green et al: Serum potassium level and dietary potassium intake as risk factors for stroke in Neurology - 2002
[2] Young: How to increase serotonin in the human brain without drugs in Journal of Psychiatry and Neuroscience – 2007. Pdf here

Bananas and (healthy) sugars

The prevalence of overweight and obesity has risen dramatically over the past few decades. It is a result from a continued imbalance between food intake and daily physical activity. While it cannot be denied that fat is the main cause of weight gain, it seems that sugars are getting much of the blame.

However, studies have revealed that increased consumption and increased portion sizes may be the reason that we and our children are ingesting far too much sugar. Between the late 1970s and the late 1990s, a 123% increase in soft drink consumption among children and adolescents was reported[1] in the US.
[Image: www.fiteveryday.com]
Now we have soft drinks that are marketed as light and are sweetened with high-intensity sweeteners, compounds with many times the sweetness of sugar. Because these sweeteners are many times sweeter than suger, much less is required and energy contribution is often negligible.

Some naturally occurring sugars are not as sweet as sugar: fructooligosaccharides (FOS) are also used as sweeterers, they exhibit sweetness levels between 30 and 50 percent of sugar and they are excellent substitutes for sugar and fat.

Banana has been indicated as a good source of fructooligosaccharides. In a full-ripe stage, 1-kestose, a fructooligosaccharide, was accumulated in all tested bananas with amounts between 297 and 1600 µg/g of dry matter[2].

[1] French et al: National trends in soft drink consumption among children and adolescents age 6 to 17 years: prevalence, amounts, and sources, 1977/1978 to 1994/1998 in Journal of the American Dietetic Association - 2003
[2] Der Agopian et al: Identification of fructooligosaccharides in different banana cultivars in Journal of Agricultural Food and Chemistry - 2009

Chili peppers come to the rescue of bananas

Bananas are susceptible to all sorts of diseases. One of those pests is Banana Xanthomonas wilt (BXW), caused by the bacterium Xanthomonas campestris pv. Musacearum, and it is considered one of the most devastating diseases of bananas in the Great Lakes region of Africa.

It has been identified in the 1960s in Etiopia on a close relative of the banana, the Ensete ventricosum. It has then spread rapidly and has to date been diagnosed in several Central and East African countries, such as Rwanda, Congo, Tanzania, Kenya, Burundi and Uganda. The rapid spread of the pathogen is threatening the livelihood of millions of Africans who rely on banana fruit for food security and income. The disease is very destructive and is infecting all banana varieties, including both East African Highland bananas and most exotic cultivars of the banana.
Not one banana cultivar in the affected region has shown any resistance to Banana Xanthomonas wilt. Chili peppers however, have antibacterial properties and scientists have been able to transfer two separate genes form a chili pepper to a banana.

The two genes, encoding the proteins plant ferredoxin-like amphipathic protein (pflp) and hypersensitive response-assisting protein (hrap), did induce a hypersensitive respons and systemic acquired resistance within the banana. The proteins work by quickly killing the cells that come into contact with the disease-spreading bacteria, blocking the disease from spreading any further.
The results of the study confirmed that expression of the Pflp gene in banana results in enhanced resistance to BXW: About 67% of transgenic lines evaluated were completely resistant to BXW[1].

The majority of transgenic lines (six of eight) expressing Hrap did not show any symptoms of infection after artificial inoculation of potted plants in the greenhouse, whereas control nontransgenic plants showed severe symptoms resulting in complete wilting[2].

Which is a promising step forward. Thanks to the trusty chili pepper.

Field trials in Uganda showed that the banana showed complete resistance to the wilt over three generations.

[1] Namukwaya et al: Transgenic banana expressing Pflp gene confers enhanced resistance to Xanthomonas wilt disease in Transgenic Resistance - 2012
[2] Tripathi et al: Expression of sweet pepper Hrap gene in banana enhances resistance to Xanthomonas campestris pv. Musacearum in Molecular Plant Pathology - 2010

A noteworthy banana: Sikkim Banana

Sikkim was once a tiny monarchy in the Himalayan mountains, bordering on Nepal, China and India. In 1975, a referendum overwhelmingly abolished the monarchy and Sikkim subsequently became part of India. Not many plants are hardy enough to survive the altitude and cold but the Sikkim banana (Musa sikkimensis) does.

In its natural environment, the Sikkim banana grows in altitudes of more that 2000 meters. The same species can also be found in the mountainous terrain of northern Thailand. The habitat is known for its long winters with its snow, high winds and frost. That means that the Sikkim banana can also be grown in temperate climes of northern Europe and North-America.
[Image: www.bananas.org]
The Sikkim banana is a robust plant that grows very large under favourable conditions: the pseudotrunk can reach a height of more that four meters and can be half a meter in diameter.

The fruits are edible but full of seeds. The fruits are described as lax, arising from large, brown callosities on axis, angled at maturity. The pulp is scanty, dirty white to pale brownish-pink. The taste is described as being sweet with an aftertaste of watermelons. One can grow this species easily from seed.

The Banana (Trade) Wars

Since the 1800s, bananas, coffee and cane sugar have been part of a worldwide system of production, shipping, selling and consumption. But the banana trade was historically dived between two major powers: Latin American bananas were the domain of large American companies, while Caribbean bananas were regulated by European trade agreements.

The so-called Dollar-bananas have been regulated by so-called free market conditions shaped by the powers of these corporations, while African, Caribbean and Pacific (ACP) bananas were favoured by European consumers because these were former Dutch, British, French and Belgian colonies.

The conflict the between the ACP and dollar banana regimes – the so-called banana wars – illuminates the historical tensions between these two totally different systems. It also highlights the two different styles of colonialism: European states used direct rule, while the United States and the American companies used indirect rule. If a Latin American state would not readily comply with the wishes of the likes of United Fruit, an American military intervention was not unlikely to happen.

So, while the large companies are still favoured by the American government, they continue to lose their power. United Fruit Company ultimately became Chiquita, went bankrupt in 2002 and re-emerged as Chiquita Brands. Dole went into private ownership again in August 2013 and Del Monte has been sold and split up several times. The part that sells bananas in now called Fresh Del Monte Produce Inc.

The family history of bananas

Recently, scientists have sequenced the complete genome of the banana and some insightful information can be cleaned from that. Now, for the first time we can be certain which other species can be regarded as direct relatives of the banana.

The banana is a giant herb and close family members include rice (Oryza sativa) and ginger (Zingiber officinale).

Around 65  Million years ago a giant meteorite smashed into the coastal area of eastern Mexico. That event heralded the end of the age of the dinosaurs but it also had a profound effect on other species, such as plants. The genome of the tomato was altered[1] as a result of the changing conditions on the planet. It was tripled in size in order to survive. Lycopene was formed and since then it got its red colour. Other genes disappeared, making it non-toxic.
[Image from scientific article]
The banana was affected too by that event and the genome is suggesting that two Whole-Genome Duplications (WGDs), denoted as α and β, occurred in that period, that is called the Cretaceous–Tertiary boundary[2].

[1] The Tomato Genome Consortsium: The tomato genome sequence provides insights into fleshy fruit evolution in Nature - 2012
[2] D'Hont et al: The banana (Musa acuminata) genome and the evolution of monocotyledonous plants in Nature - 2012