Bananas, the most popular food crop in the world, have had a run in with extinction before and there’s a possibility that it might happen again. Cavendish bananas, most commonly seen in grocery stores in the Western hemisphere, are currently under attack from a recently emerged strain of Fusarium oxysporum, also known as Tropical Race 4 (TR4) that causes the plant to wilt and die, according to CNN.
TR4 was found in Taiwan, Malaysia, and Indonesia as early as the 1990s, and has spread to many other Southeast Asian countries since. If the outbreak hits Latin America and the Caribbean region, the export banana industry could see some serious damages. Since Cavendish bananas are nearly identical and lack genetic variation, the plant is highly vulnerable to disease, in this case TR4.
Until the 1960s, Gros Michel, also called “Big Mike,” was the primary variety of bananas in the West. During the ‘50s and ‘60s, a fungal disease called Fusarium wilt, or Panama disease, spread across plantations. The disease made the plant unable to transport water and nutrients, which in turn made the plants wilt and die. The disease spread easily in soil, water, and infected material and was immune to fungicides. Since Cavendish bananas were resistant to the strain of the disease that wiped out “Big Mike,” the banana population was saved.
Although bananas made a swift comeback, the Cavendish variety are still susceptible to a disease called Black Sigatoka, which “attacks the plants' leaves, causing cell death that affects photosynthesis and leads to a reduction in fruit production and quality,” CNN reported. Banana growers are currently able to keep at bay by removing infected leaves and applying fungicides. However, keeping the Cavendish bananas alive and well may come with negative side effects, including environmental harm from the use of fungicides and a potential resistance to the chemicals.