Login to account Create an account  


Thread Rating:
  • 1 Vote(s) - 5 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Bananas in peril.... yup, another fungus...
#1
I love bananas.  Always have.

But I recall being told, with some degree of certainty, that we are pretty much dependent on a single species of banana here in the US.  It had been selected because it was resistant to a particularly nasty fungus that had threatened an old-time favorite many decades ago... that species had pretty much fallen into near extinction due to a fungus that our new species was able to resist.

This article filled in the gaps of my knowledge of bananas quite well...

From ZME Science: The banana apocalypse is coming. Can we stop it this time?
 

Humans love bananas. We eat around 100 billion bananas per year, or 273 million bananas a day. We also grow 1000 or so varieties of bananas — but there’s a catch; one of these varieties, the Cavendish banana, makes up around 50% of global production. Whenever you go to buy a banana, especially if it’s in a supermarket, it’s most likely a Cavendish banana.

It’s not the first dominant cultivar, either. Before the Cavendish, we had the Gros Michel banana, which dominated global markets. In the early 20th century, however, the Gros Michel banana was brought to its knees by a fungus: Fusarium oxysporum. Specifically, it was attacked by the R1 strain of this fungus. It caused Fusarium wilt, also known as Panama disease, leading to the near-extinction of the Gros Michel variety. The banana industry responded by adopting the Cavendish banana, which was resistant to R1.



Now a new threat has reared it's ugly head.. Our go-to strain, the Cavendish banana is now facing a new (genetically-unrelated) fungal strain to which it has no such resistance...
 

Now, the strain (called TR4) has been detected in banana plantations across Asia, Australia, Africa, and Latin America. Its spread has alarmed scientists and industry stakeholders as it seems to infect Cavendish bananas as well as a number of other cultivars.


As the history of the bananas we eat is fascinating... it concerns me that this new pathogen is setting the stage for genetic manipulation to be "the answer."  And I can only pray that such a solution is not a "mistake."
 

“We have spent the last 10 years studying this new outbreak of banana wilt,” says Ma, who is an expert in Fusarium oxysporum, which is not a single species but a “species complex” with hundreds of different varieties that specialize in affecting different plant hosts. These varieties are determined by the acquisition of strain-specific accessory genes in addition to a shared core genome. “We now know that the Cavendish banana-destroying pathogen TR4 did not evolve from the race that decimated the Gros Michel bananas. TR4’s genome contains some accessory genes that are linked to the production of nitric oxide, which seems to be the key factor in TR4’s virulence.”

In the study, researchers identified the genetic and biochemical factors that underpin TR4’s virulence. Unlike its predecessor R1, TR4 lacks the accessory chromosomes that typically carry virulence genes in other Fusarium strains. However, it compensates with a suite of accessory genes embedded within its core chromosomes.

Upon infection, TR4 induces a burst of nitric oxide (NO) production within its mitochondria. This NO burst is believed to overwhelm the banana’s defense mechanisms. In particular, it may interfere with the plant’s ability to manage cellular stress.



I suspect that a genetic approach will be the knee-jerk response to the problem, leaving us in a position of changing one of nature's perfect foods... 

A good read....

[edit to add]  A research paper upon which the article is based from Nature Microbiology: Virulence of banana wilt-causing fungal pathogen Fusarium oxysporum tropical race 4 is mediated by nitric oxide biosynthesis and accessory genes
Reply
#2
I have a banana every day for breakfast.
It's good for the heart.
Hope our bananas are just fine.   
I don' tknow what I'd do for breakfast without them.
make russia small again
Don't be a useful idiot.  Deny Ignorance.
 
Reply
#3
Late to the party here, I know, but I saw this while responding to another question here.

Banana growing and harvest is a really interesting process.  I never realized how difficult it is to actually get a bunch of bananas to the store shelves.  It's like crazy, CRAZY, difficult.  I toured a Dole plantation several years ago on a business trip I was on down in the Caribbean. 

Everybody who loves bananas knows just how fast they turn from just right to mush.  That same level of exacting timing is replete throughout the whole process of raising and harvesting bananas.  One real stunner in the process was the realization (when one of the Dole guys pointed this out) that any given bunch of bananas has to be harvested on an exact day, and that day varies from tree to tree.  When you look at a banana plantation there's like tens of thousands of banana trees.  And because bananas have to be 'in season' year round, this means there's all different ages of plants in a plantation.  What this translates into is effectively every single tree has to be examined every single day.  If they miss the optimal time for cutting a bunch down, even by a single day, the bananas won't make it to market before they're already over-ripe.  So, as we all have seen, sometimes you see green bananas in the stores, but they can't be too green because if they're picked too soon they won't fully ripen.  Time pressure on both ends, too early and too late.  If we back up from what we see show up in the store (i.e. semi green banana) then it becomes clear that the bunches get cut and split when they're totally green.  Now imagine looking at a plantation with tens of thousands of trees, all with totally green bananas on every tree, and trying to figure out which ones to cut at the precise time.  Like...WOW!  I had no idea.

It's a wonder bananas don't cost $50 bucks a bunch (I should probably be quiet here because someone might read this and jack up the prices).  On top of all of this, you have to factor in waste, and there's a lot of it with bananas.  If the bananas get delayed anywhere in transit (storm, shipping delay, etc., etc.) then the whole shipment might be lost.

The process of getting a simple banana to the store shelf is one of the most amazing and fascinating things in the grocery business!  Think about that next time you peel that banana.  In fact, I think I'll go have a banana right now (the wife picked up a bunch just yesterday)!

edit - When you add all this to Max's OP about 'limp bananas', erm, fungus causing banana 'rigidity dysfunction' (still doesn't sound right)..."Is that a banana in your pocket, or are you just a fungus??"...yeah, well you get the idea; it's a wonder we can get bananas at all.

On a serious note, when I was stationed in Malaysia I always used to go to the open air night market on Saturday nights.  It wasn't uncommon to see 15-20 different strains of bananas, everything from plantain type starchy bananas, to mini bananas, to regular bananas, to different colored and shaped bananas.  All of them unique in taste, texture, size and shape.
Reply
#4
It really is amazing how the just-in-time works. I try to find the four-finger bunch of bananas at the store because that is what lasts when I have one a day with breakfast. Well, every few weeks. Usually the last banana always get a little mushy! But that's okay chopped up in granola and yogourt.

Yes not much variety because they're so sensitive! And don't freeze. Or can. Pretty much all you do is make those dried unrehydratable banana chips which are tasty but too much added sugar and they always get stuck in molars! Sheesh, like all-day bananas.

Oh and I have a neat little banana stand with a hook so they don't touch shelf or counter; they last longer. And keeping them cool helps too. Don't know if light or lack thereof helps, like potatoes?

The banana flavour that is artificial is odd too, apparently it was invented back last century and then it tasted like bananas but since they selected the ones you get in the store now that are different that's the only place you get that particular flavour anymore and they don't taste alike at all. Still tasty actually although some people hate it.

What's awesome are plantains which are like bananas or a type of them. Great to make like 3/4" slices of them and then deep-fry them a little then you let them cool a tiny bit and then squish them down with a glass to make little pancakes and sprinkle them with confectioners sugar. A great snack! South American I think.

It is like Irish potato blight - the hazards of monoculture.
I followed the Science, and all I found was the Money.
Reply
#5
(10-05-2024, 06:15 AM)FlyingClayDisk Wrote: On a serious note, when I was stationed in Malaysia I always used to go to the open air night market on Saturday nights.  It wasn't uncommon to see 15-20 different strains of bananas, everything from plantain type starchy bananas, to mini bananas, to regular bananas, to different colored and shaped bananas.  All of them unique in taste, texture, size and shape.

This is the important part of the issue here. Because stores rely on basically one type for most of its banana sales. It's like nobody learned a damn thing from the Irish Potato Famine. 

Personally, some of those lesser sold bananas are worlds better than the cavendish variety and I wish they would be sold here (thanks a lot Clinton administration). I don't get we don't do what they do in Iceland when it comes to growing our own bananas, I have a friend that lives in an Earthship down in New Mexico, and they grow their own bananas inside. There are some tricks to it but still they eat their own grown bananas. We could do that, just like in Iceland, here at home. Why we don't is due to ignorance of the techniques.
Reply
#6
In the Philippines there are hundreds of wonderful varieties of bananas.

From small sweeter than candy to almost potato tasting used in soups.

Not a problem there. 

Genetic diversity, I am guessing.
Reply



Forum Jump: