Fusarium wilt tropical race 4 (TR4), is an insidious fungal disease that kills banana plants by disrupting their vascular systems, and it can persist in soil for decades. No known fungicide or biocontrol measure has proven effective against TR4.
In 2015, Randy Ploetz, the professor of plant pathology at the University of Florida who discovered Tropical Race 4 was quoted by Quartz as saying that while TR4 had not been identified as being found in Latin America, it was possible that the fungus was already there.
However, with Latin America being the world’s largest exporter of bananas, the finding in the La Guajira region of Colombia has put the whole region on alert. Wageningen University and the biotech company KeyGene, both in the Netherlands, used genome sequencing and molecular diagnostics to confirm the TR4 diagnosis in infected plant samples from Colombia.
After eradicating plants covering nearly 170 hectares (420 acres) of quarantined farmland, the Colombian Agricultural Institute (ICA) in Bogotá has now announced plans to expand biosecurity efforts that include increasing sanitary control measures at all ports, airports, and border points,
Colombia’s government is also considering providing funding to small and medium-size banana exporters to help them implement better biosecurity measures, such as disinfecting machinery, shipping containers, and footwear in quarantined areas. Additionally, agriculture ministers from across the region met in Quito on August 5 to discuss plans to prevent further outbreaks.
TR4 is spreading fast around the globe
First identified in Taiwanese soil samples in the early 1990s, TR4 remained confined to Southeast Asia and Australia, until its presence was confirmed in both the Middle East and Africa in 2013, according to National Geographic.
“Once you see it, it is too late, and it has likely already spread outside that zone without recognition,” says Gert Kema, Professor of Tropical Phytopathology at Wageningen University in the Netherlands whose lab analyzed soil samples to confirm TR4 in Colombia, as well as in earlier outbreaks.
Researchers at Wageningen University have also found out that strains of the fungal samples taken from soil and plants around the world are genetically identical. Gert Kema, a banana expert at Wageningen UR, says: “This research demonstrates that the quarantine measures and information provided around the globe apparently have not had the desired effect.
And this information does not bode well for consumers or the over 400 million people who rely on bananas for 15 to 27 percent of their total daily calories. Bananas have become the fourth most important food product in the world, after rice, wheat, and milk. Where bananas were once a snack food, they have now become an important food source for 9/10ths of the world’s poor.
