Reunion banana farmer faces financial ruin from advancing fungal plague

Gilbert Bafinal grows bananas in Ravine des Cabris, on the French island of Reunion, and a single fungal disease could strip away 90 percent of his income. He depends almost entirely on the crop. If the disease arrives, he said, he would not know what else to do. The threat is Tropical Race 4, or TR4, a fungus that has already destroyed plantations in Mayotte, the Comoros, and Madagascar. It has not yet reached Reunion. Bafinal grows Grande Naine, a variety considered especially vulnerable to the pathogen, which makes his situation particularly exposed. Switching to resistant varieties presents its own problem. Bafinal fears customers will reject the taste. Banana shortages have hit Reunion before, after cyclones, with prices reaching 8 to 10 euros per kilogram for months. TR4 would be far worse. Some parcels could become permanently unusable for current varieties, forcing the island to import more bananas at higher transport costs. By contrast, the island has so far avoided confirmed infection. Eric Lucas, diversity officer at the Reunion Chamber of Agriculture, said Reunion has had suspicions and alerts but no confirmed cases. He warned that the disease is very present in Mayotte, the Comoros, and Madagascar, and that travelers can carry it back on contaminated soil or plant material. His message is direct: the danger is too great to risk bringing back a cutting or plant. The biology of TR4 leaves little room for error. The fungus enters banana plants through the root system and progressively invades the plant's vascular vessels, according to Dr. Isabelle Robène, a researcher at Cirad. Leaves yellow. The plant withers and dies. Once established, the pathogen is very difficult or impossible to remove, its spores surviving indefinitely in soil with no chemical treatment capable of eradicating them. Reunion customs recorded 157 instances of illegal plant product introduction in 2025. About 30 percent came from mainland France, 25 percent from Madagascar, and nearly 20 percent from Mayotte, including products arriving from the Comoros via that island. Customs agents have received specific instructions about TR4 risk, and flights from Mayotte now face enhanced monitoring. About fifty sentinel parcels are under official surveillance through a system run by the regional agriculture authority and implemented by the departmental federation for pest defense. Cirad has developed a rapid detection test usable on site without heavy laboratory equipment. A positive result must be confirmed by the national food, environment, and labor safety agency. No TR4 outbreak is currently confirmed on Reunion. Whether the combination of border controls, field surveillance, and rapid testing proves sufficient to hold the line, as the disease tightens its grip on neighboring islands, remains the question every banana farmer on the island is living with.