
The supermarket variety of the banana fruit, the Cavendish, is currently threatened by a disease know as "Tropical Race 4."

Panama disease caused by Tropical Race 4 (TR4) in northern Mozambique. The picture, taken in January 2015, shows a banana farm planted with the Cavendish variety.

The disease attacks the vascular tissue of the banana plant, impairing its ability to draw water and nutrients from the soil.

So far, the disease in Africa seems to be contained to just two banana plantations in Mozambique, one of which is pictured here.

The illness is a relative of the "Panama disease," which wiped out the plantations of bananas in the 1960s, and prompted the industry to move to a different cultivar.

Africa is a growing exporter of bananas, with about 15 percent of the market. But many Africans depend on the fruit and get up to 90 percent of their calories from local banana varieties.

A South Sudanese market trader sits in his shop where he sells imported bananas from Uganda. Another disease, called "BXW," has nearly destroyed Uganda's banana industry about a decade ago.

An Ivorian woman works at a bananas plantation in Bonne, 100 km north of Abidjan.

Particularly important to Africa is the East African Highland Banana (EAHB), a staple food for 80 million people. Uganda alone has about 120 varieties of this type of banana.

India is the world's leading producer of bananas, and has hundreds of local varieties.

"Tropical Race 4" has already spread from Asia to Australia, where the diffusion of the fungus has been slow but steady, despite the precautions put in place by local growers.



