Farmers are going bananas battling diseases that threaten the popular yellow-skinned fruit. Fungi cause some killer plant blights. And new analyses show these pathogens are growing nastier. Some of the genes in the fungi are changing in ways that allow those fungi to steal the banana’s nutrients. The new data could help researchers breed bananas to thwart the fungal threats.
Rest assured, you won’t get sick eating bananas that came from infected plants. The fungi spread by air and only attack the plants’ leaves. The infected greenery develops small yellow spots. Over time, they darken and expand. The infected tissue eventually dies. Less tissue that’s healthy will slow the plants’ photosynthesis. This is the process by which plants use sunlight to make food. So infected plants produce fewer bananas.
Farmers fight fungal diseases with chemical sprays. But those sprays are expensive. In fact, they can add up to nearly a third of the cost of growing bananas. Those chemicals also can harm the environment. Even worse, the fungi have begun to resist the killing effects of certain sprays. So researchers are looking for new ways to control the fungal infections.
One of the culprits behind the banana blight is a disease known as Black Sigatoka (SEEG-uh-TOKE-uh). It takes its name from a town on the South Pacific island nation of Fiji. That’s where the blight first turned up in the 1960s. Since then, this fungus has spread widely around the world. So have two related fungal species. They cause Yellow Sigatoka and Eumusae (Yu-MYOO-say) leaf spot.