Overview
Banana evolution over thousands of years has involved a protracted battle with microorganisms. Bananas have been given new life by scientists despite numerous times being on the verge of extinction. One of the world's oldest fruits, bananas have a specific tie to China as a significant commercial crop. They are cherished by many as a "happy fruit" because of the tryptophan they contain, which can be converted to serotonin. Due to their high mineral content, which includes potassium and salt, they are also well-known among fitness enthusiasts as a "superfruit". Few people are aware of the protracted conflict between microbes and bananas, though. Recent articles from the Japanese Economic News titled "Bananas on the brink of extinction due to the spread of wilt disease" have reignited the debate about the future of bananas. How much can wilt disease shorten a banana's "lifespan"? Is there evidence of a decline in this fruit's yearly global production, which exceeds 100 million tonnes? Journalists for the Global magazine tracked the continuous conflicts between science and the microbes responsible for this famous fruit by speaking with experts in the disciplines of tropical fruits, microbiology, and genetic engineering.
Introduction:
But the Big Mac has also come up against its arch-enemy, a fungus known as Fusarium oxysporum f. sp. cubense, which causes Fusarium wilt. The vascular tissue of the plant, which is in charge of conveying water and nutrients, can be destroyed by this type of fungus, which has strong vitality and spreads quickly in the soil where bananas grow. As a result, the bananas wilt and die like a patient who cannot eat. According to biological scientists, this fungus has a great capacity for adaptation and spread and can persist in the soil for more than 50 years. It is also common in flowing, irrigation, and precipitation, as well as on farm equipment and seedlings. "As soon as this fungus comes into contact with the roots of a banana tree, the entire plantation will soon become infected with Panama disease (also known as Fusarium wilt), and the area will face abandonment and have to switch to other crops, resulting in very heavy losses," said Li Chaosheng, Director of the Banana Genetics and Breeding Research Laboratory at the Guangxi Academy of Agricultural Sciences. First identified in Australia in 1874, Fusarium oxysporum f. sp. cubense race 1 (FOC1) spread to Panama in Central and South America in 1910, where it resulted in the destruction of several banana plantations and poor harvests. Experts called the illness "Panama disease" since it originated in Panama and spread from there. At the time, the illness was still spreading in the well-known regions that produced bananas, resulting in significant losses. By the 1950s, Big Mac was forced to leave the global trade market because it was unable to continue with extensive planting and manufacturing. The Big Mac was replaced with the "Lady Finger" banana, which is inherently resistant to FOC1, in both global planting and commerce. FOC4, a novel pathogen that might make Lady Finger bananas prone to illness, first emerged in the 1960s. Almost all of its banana kinds are susceptible to infection, despite the majority of its gene sequence being similar to FOC1. This makes it more potent than FOC1. FOC4 moved to Indonesia and Malaysia in the 1990s, according to experts, after invading the Philippines in the 1970s. This disease was discovered in significant banana-producing regions all over the world in the ensuing decades. The same virus, FOC4, was initially identified in Taiwan, China, in 1967; a decade later, in Guangdong, China, in 1996. The pathogen first appeared in Fujian in 2000, then Hainan in 2001, Guangxi in 2006, and Yunnan in 2007. As of right now, the invasion has caused varied degrees of loss and harm in well-known banana-producing regions all over the world. "At its height, the Guangxi banana planting area was over 1.8 million mu, but as a result of the damage caused by the wilt disease and other factors, it has decreased to just over 600,000 mu, or around two-thirds of the original size. The acreage used for planting bananas have also been drastically reduced in Guangdong, Hainan, Yunnan, and other locations, according to Li Chaosheng. In a way, the wilt disease regulates the over reliance on one banana variety through natural means. Accelerating the cultivation and promotion of novel banana varieties with disease resistance or immunity is required to stop the loss brought on by Fusarium wilt.
A well-kept banana garden can persist for eight to twelve years because bananas are a perennial plant. Bananas have a robust root system, making it challenging to manage soil-borne illnesses. It is difficult to apply chemicals around every root, even those that are quite powerful. Expert Sun Xianyun from the Institute of Microbiology of the Chinese Academy of Sciences, who has long studied fungi, argues that because bananas are perennial and require significant initial inputs, they cannot be picked and replanted like vegetables can. Once soil-borne illnesses appear, the losses for orchards that are 3 to 5 years old and are in their peak production phase will be very high.
Bananas are also afflicted by illnesses like black streak disease, black sigatoka disease, cigar end rot, anthracnose, and fusarium wilt, which pose a threat to the health of the global banana sector. According to a directory of banana diseases published by the Chinese Academy of Tropical Agricultural Sciences' Institute of Environment and Plant Protection, 74 different diseases, including nematode diseases, bacterial diseases, viral diseases, phytoplasma diseases, fungal diseases, and physiological diseases, can affect bananas. The principal disease, banana wilt, has damaging effects that are getting worse.
Biotechnology Launches Banana "Defence War"
Around 120 nations and areas are thought to produce bananas globally. Bananas are also a staple food for approximately 600 million people and the fourth-largest grain crop in the world.
In order to stop the spread of fusarium wilt foc1, humans have looked for resistant alternative types, such as Cavendish bananas. The lethal viruses and diseases that attack bananas are altering and evolving, nevertheless. They resist easy retreat and instead look for ways to survive by altering plant species and advancing technologies.
According to Li Huaping, head of the Plant Protection Function Research Room of the National Banana Industry Technology System and professor of plant protection at the South China Agricultural University, "Plants and microbes will co-evolve, which is a natural process. Any microorganism that wants to survive will change in an adaptive way.
Fusarium wilt foc4, the present threat to the worldwide banana industry, was created by foc1, the "culprit" that was once responsible for Big Mike's extinction, according to Li Huaping. Foc1, which did not initially infect Cavendish bananas, underwent adaptive mutation and acquired the capacity to infect them when the resistant Cavendish banana became the primary planting variety.
Genomic variations exist in the wide population of Spiaria falcata. A certain population unexpectedly developed the potential to infect Cavendish bananas through the process of gene exchange between species, which resulted in the infection of Cavendish bananas.
