As I reported in my popular, illustrated book, The Malevolent Designer: Why Nature's God is Not Good, we could be about to say goodbye to the banana.
Yes! We Have No Bananas, Thanks to Fusarium Wilt.
The soil-borne fungus Fusarium oxysporum f. sp. Cubense is a specialised form of F. oxysporum which parasitized banana plants (Mussa sp.), causing Panama disease or Fusarium wilt. Entire plantations can be wiped out in a year.
It is believed to have originated in Southeast Asia and was first reported in Australia in 1876. Since then, it has spread to almost all banana-producing parts of the world. One method of spread is by infected rhizomes which appear normal. Cultivated bananas are seedless so need to be reproduced asexually with offshoots or rhizomes. The fungus kills the plant by triggering a self-defence mechanism that produced first a gel, then tylose which block the conductive tissues and prevent water and nutrients from travelling up from the roots.
By the mid-20th Century, resistant cultivars of the ‘Cavendish’ banana had been developed. However, the fungus has managed to overcome this resistance in the Eastern Hemisphere, and this is expected to spread to the Western Hemisphere. Currently, there are no other resistant cultivars available. There is now a real possibility that this economically and nutritionally important crop could become extinct!
Creationism’s putative intelligent designer appears to have a down on bananas and has twice modified a soil-born fungus to kill them. Firstly before 1876 and then again in the 20th Century, to overcome resistance in the ‘Cavendish’ cultivar. It doesn’t just stop at bananas, either. F. oxysporum also affects the plantain, Mussa acuminata × balbisiana, which is a staple crop in tropical regions.
The soil-borne fungus Fusarium oxysporum f. sp. Cubense is a specialised form of F. oxysporum which parasitized banana plants (Mussa sp.), causing Panama disease or Fusarium wilt. Entire plantations can be wiped out in a year.
It is believed to have originated in Southeast Asia and was first reported in Australia in 1876. Since then, it has spread to almost all banana-producing parts of the world. One method of spread is by infected rhizomes which appear normal. Cultivated bananas are seedless so need to be reproduced asexually with offshoots or rhizomes. The fungus kills the plant by triggering a self-defence mechanism that produced first a gel, then tylose which block the conductive tissues and prevent water and nutrients from travelling up from the roots.
By the mid-20th Century, resistant cultivars of the ‘Cavendish’ banana had been developed. However, the fungus has managed to overcome this resistance in the Eastern Hemisphere, and this is expected to spread to the Western Hemisphere. Currently, there are no other resistant cultivars available. There is now a real possibility that this economically and nutritionally important crop could become extinct!
Creationism’s putative intelligent designer appears to have a down on bananas and has twice modified a soil-born fungus to kill them. Firstly before 1876 and then again in the 20th Century, to overcome resistance in the ‘Cavendish’ cultivar. It doesn’t just stop at bananas, either. F. oxysporum also affects the plantain, Mussa acuminata × balbisiana, which is a staple crop in tropical regions.
Rubicondior, Rosa, The Malevolent Designer: Why Nature's God is Not Good; p 40-41
Tell me all about the fusarium wilt caused by Fusarium oxysporum f*sp* cubense that is destroying banana plantations. Fusarium wilt, caused by the soil-borne fungus Fusarium oxysporum f.sp. cubense (Foc), is a devastating disease that affects banana plants worldwide. It is particularly notorious for causing Panama disease, which has historically wiped out entire banana plantations and continues to be a major threat to global banana production.First, let's dispense with the ludicrous attempt to dismiss these examples of malevolent design if we accept the notion of intelligent [sic] design for the moment. It was invented by creationists who inadvertently showed how creationism is religion dressed up as science by assigning anything they find embarrassing in nature, like parasites and organisms which increase the suffering in the world as the result of 'Sin', not their designer god (who remains the only entity capable of designing living organisms).
The Pathogen: Fusarium oxysporum f.sp. cubense (Foc)
- Foc Structure: Foc is a specialized form of the species Fusarium oxysporum. It is divided into several races, with Race 1 and Tropical Race 4 (TR4) being the most significant in terms of impact.
- Race 1: Was responsible for the Panama disease epidemic that nearly wiped out the Gros Michel banana cultivar in the mid-20th century.
- Tropical Race 4 (TR4): A more virulent strain that affects the Cavendish cultivar, which replaced Gros Michel and now accounts for about 47% of global banana production.
- Life Cycle: Foc is a soil-borne fungus that infects banana plants through their roots. The fungus colonizes the plant's vascular system, particularly the xylem, where it disrupts water and nutrient transport, leading to the plant's wilting and eventual death. Once established, Foc can survive in the soil for decades, even without a banana host.
Symptoms
- Yellowing of Leaves: One of the earliest symptoms is the yellowing of older leaves, starting at the margins and moving toward the midrib.
- Wilting: As the disease progresses, leaves wilt, droop, and eventually die. The plant may exhibit stunted growth.
- Internal Symptoms: When the plant is cut open, the vascular tissues (xylem) appear discolored, usually brown or red, indicating the presence of the fungus.
- Death: The plant eventually succumbs to the infection, often collapsing completely.
Impact on Banana Cultivation
- Economic Impact: The disease is highly destructive, leading to significant economic losses, especially in countries that rely heavily on banana exports. TR4 has spread across Asia, Africa, the Middle East, and more recently into Latin America, threatening banana production worldwide.
- Agricultural Impact: Because Foc can persist in the soil for decades, once an area is infested, it is virtually impossible to grow bananas there again without resorting to alternative crops or advanced management practices.
Control and Management Strategies
- Quarantine and Containment: Limiting the spread of TR4 by imposing strict quarantine measures and monitoring the movement of infected plant material and soil.
- Resistant Cultivars: Breeding and deploying resistant banana varieties is a key strategy, although this is challenging due to the genetic uniformity of commercially grown bananas like Cavendish.
- Cultural Practices: Crop rotation, soil fumigation, and the use of cover crops can help reduce the presence of Foc in the soil. However, these methods are not foolproof and can be expensive.
- Biological Control: Some research is focused on using beneficial microorganisms or biocontrol agents to suppress the growth of Foc in the soil.
The Future of Banana Cultivation
The spread of TR4 poses a significant threat to global banana production. Scientists are racing to develop new banana varieties that are resistant to TR4, but the process is slow and complex. In the meantime, efforts to contain the disease and minimize its spread are crucial to preserving banana cultivation as a viable agricultural practice. The situation highlights the vulnerability of monoculture systems and the need for greater genetic diversity in banana crops.
The story is that 'Sin' (by Adam & Eve) caused 'genetic entropy' which has resulted in organisms' 'devolving' (© Michael J. Behe) from some assumed initial created perfection. This might appeal to creationists with no understanding of genetics or evolution, but biologically, it is nonsensical. Apart from the nonsense of a funder couple born without ancestors, any mutation which is detrimental to an organism will be quickly removed from the species gene pool by natural selection, but any mutation which improves an organism's ability to survive and reproduce in that environment will tend to increase in the gene pool, and so is classically evolutionary. It is nonsensical to argue that something better than its predecessor is less perfect than that predecessor.
So, what creationists must decide is whether the new improves Fusarium oxysporum fungus was intelligent designed (by a malevolent designer) or whether it evolved.
And how it evolved (or was it redesigned?) is the subject of a paper in Nature Microbiology by an international team of scientists led by the University of Massachusetts Amherst, and a University of Massachusetts Amherst news release:
The Banana Apocalypse is Near, but UMass Amherst Biologists Might Have Found a Key to Their Survival
Discovery of molecular mechanisms used by the banana-destroying microbe brings hope to the breakfast table
The bananas in your supermarket and that you eat for breakfast are facing functional extinction due to the disease Fusarium wilt of banana (FWB) caused by a fungal pathogen called Fusarium oxysporum f.sp. cubense (Foc) tropical race 4 (TR4). However, thanks to recent research from an international team of scientists led by the University of Massachusetts Amherst, we now know that Foc TR4 did not evolve from the strain that wiped out commercial banana crops in the 1950s and that the virulence of this new strain seems to be caused by some accessory genes that are associated the production of nitric oxide. The research, published in Nature Microbiology, opens the door to treatments and strategies that can slow, if not control, the as-of-yet unchecked spread of Foc TR4.
Today, the most popular type of commercially available banana is the Cavendish variety, which was bread as a disease-resistant response to the Gros Michel extinction. For about 40 years, the Cavendish banana thrived across the globe in the vast monocultured plantations that supply the majority of the world’s commercial banana crop.The kind of banana we eat today is not the same as the one your grandparents ate. Those old ones, the Gros Michel bananas, are functionally extinct, victims of the first Fusarium outbreak in the 1950s.
Professor Li-Jun Ma, senior author
Professor of biochemistry and molecular biology
University of Massachusetts Amherst, Amherst, MA, USA.
But by the 1990s, the good times for the Cavendish banana had begun to come to a close.There was another outbreak of banana wilt. It spread like wildfire from South-East Asia to Africa and Central America.
Dr. Yong Zhang, lead author
Department of Biochemistry and Molecular Biology
University of Massachusetts Amherst, Amherst, MA, USA.>[Professor Ma 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 have spent the last 10 years studying this new outbreak of banana wilt. 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.
Professor Li-Jun Ma.
To arrive at this conclusion, Yong, Ma and their co-authors from China and South Africa as well as universities in the U.S., sequenced and compared 36 different Foc strains collected from all over the world, including those strains that attack Gros Michel bananas. Then, with the help of UMass Amherst’s Institute for Applied Life Sciences, the team discovered that Foc TR4, responsible for the current outbreak of banana wilt, uses some accessory genes for both production and detoxification of fungal nitric oxide to invade the host.
Fusarium wilt of banana (FWB) caused by Fusarium oxysporum f. sp. Cubense (Foc) tropical race 4 (TR4) with external symptoms of FWB in Cavendish banana.Credit: Zhang et al.
While the team doesn’t yet know exactly how these activities contribute to disease infestation in Cavendish banana, they were able to determine that the virulence of Foc TR4 was greatly reduced when two genes that control nitric oxide production were eliminated.
Identifying these accessory genetic sequences opens up many strategic avenues to mitigate, or even control, the spread of Foc TR4.
Dr. Yong Zhang,
Even so, Ma is quick to point out that the ultimate problem facing one of our favorite breakfast foods is the practice of monocropping.
Funding for this study was provided by the U.S. National Science Foundation, the U.S. Department of Agriculture’s National Institute of Food and Agriculture, the U.S. Department of Health & Human Services, the U.S. Department of Energy the National Institutes of Health, the Guangdong Science and Technology Project, CARS and the Laboratory of Lingnan Modern Agriculture Project.When there’s no diversity in a huge commercial crop, it becomes an easy target for pathogens. Next time you’re shopping for bananas, try some different varieties that might be available in your local specialty foods store.
Professor Li-Jun Ma.
AbstractVery clearly, whatever mutations made this race of Fusarium oxysporum better at invading and killing banana plants, can't logically be described as 'devolution' since it is classic evolution, so creationists must decide whether this was the result of malevolent design, or evolution. Who is going to be brave enough to choose?
Fusarium wilt of banana, caused by Fusarium oxysporum f. sp. cubense (Foc), is one of the most damaging plant diseases known. Foc race 1 (R1) decimated the Gros Michel-based banana (Musa acuminata) trade, and now Foc tropical race 4 (TR4) threatens global production of its replacement, the Cavendish banana. Here population genomics revealed that all Cavendish banana-infecting Foc race 4 strains share an evolutionary origin distinct from that of R1 strains. Although TR4 lacks accessory chromosomes, it contains accessory genes at the ends of some core chromosomes that are enriched for virulence and mitochondria-related functions. Meta-transcriptomics revealed the unique induction of the entire mitochondrion-localized nitric oxide (NO) biosynthesis pathway upon TR4 infection. Empirically, we confirmed the unique induction of a NO burst in TR4, suggesting that nitrosative pressure may contribute to virulence. Targeted mutagenesis demonstrated the functional importance of fungal NO production and the accessory gene SIX4 as virulence factors.
Zhang, Y., Liu, S., Mostert, D. et al.
Virulence of banana wilt-causing fungal pathogen Fusarium oxysporum tropical race 4 is mediated by nitric oxide biosynthesis and accessory genes. Nat Microbiol (2024). https://doi.org/10.1038/s41564-024-01779-7
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Reprinted under the terms of s60 of the Copyright, Designs and Patents Act 1988.
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This is another example out of countless infinite number of examples of the creator's cruelty and incompetence. Bananas are a healthy delicious fruit which millions of people depend on and which many fruit eating animals depend on. So why then create a disease to limit its number?
ReplyDeleteA smart idea would be to expand one's diet to other varieties of bananas besides the Cavendish variety. There are Red banana and the super delicious Blue Java Banana which tastes like ice cream.
Other wonderful fruits are Common Guava, Strawberry Guava, Papaya, Passionfruit, Pineapple, Orange, Java Plum, Chocolate Sapote, Vanilla Sapote, Eggfruit, Rambutan, Mangosteen, Raspberry, Blueberry, Strawberry, and all the Melons such as Watermelon. Fruits are one of the few things in Nature that I like. I also love Parakeets, most songbirds, Doves and Pigeons, dogs, and tropical islands. That's about it. These are the good in Nature.
Unfortunately the evils in Nature such as Mosquitoes, Centipedes, diseases, typhoons, tsunamis outweigh the good things in Nature. Thank you for reading.